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Storm Drainage Calcs V1LAND LE GROUP Aviator Springs Subdivision 3235 N. McDermott Road, Meridian, ID 83646 Storm Drain Management & Engineering Drainage Report Developer Investment Analytic Group, LLC 800 W. Main St., Suite 1460 Boise, Idaho 83702 Engineer The Land Group, Inc. 462 East Shore Drive, Suite 100 Eagle, Idaho 83616 Contact: James W. Gute, PE Ph: 208.939.4041 TLG Project No. 120194 ��SIONAL E � ��0\STERF.o a x 11568 04/07/2022 �T F 0 \oP 462 East Shore Drive, Suite 100, Eagle, Idaho 83616 208.939.4041 thelandgroupinc.com Aviator Springs Subdivision Meridian, ID Storm Water Management Report Site Description & Report Purpose The Aviator Springs Subdivision is located to the west of N McDermott Road between W Ustick Road and W McMillan Road in Meridian ID. The project is a subdivision consisting mostly of single-family residential lots with two commercial lots. This report analyzes the proposed storm drain facilities to be constructed by the project and confirms the adequacy of these systems to serve the needs of the project. Construction documents of the improvements have been prepared and show final details necessary for construction. Proposed Drainage System Aviator Springs will treat and infiltrate strom water through the use of above -grade infiltration basins. There are a total of sixteen basins located on common lots throughout the subdivision. Appendix A provides an overview of the proposed infiltration basins and their tributary areas. Developed Storm Volume The drainage systems have been designed in accordance with current ACHD policies and per their published design calculation spreadsheets. These use a 100-year design storm. The drainage calculations prepared using ACHD's spreadsheets are provided in Appendix B. Calculation Procedure The calculations presented in this report show that the proposed facilities are adequately sized to accommodate the expected storm water runoff from the site. Due to the irregular shape of these facilities, an "effective" area and volume was determined for each basin in order to best utilize the ACHD design spreadsheets. In addition, the geotechnical investigation report and groundwater monitoring data have both been included as appendices. 462 East Shore Drive, Suite 100, Eagle, Idaho 83616 208.939.4041 thelandgroupinc.com Aviator Springs Subdivision Appendix A Site Drainage Areas Meridian, ID Storm Water Management Report fhelandgroupinc com II I II II I I I I I I I I� I i IW I I I i 18 d I Drainage Aviator Springs Subdivision Appendix B Drainage Calculations Meridian, ID Storm Water Management Report fhelandgroupinc com ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 1 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 1.11 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 1,485 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 928 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 149 ft' Primary Treatment/StorageBasin V 1,337 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 1,485 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 4,884 8,242 7,921 4,895 3,212 0.67 0.95 0.45 0.95 0.45 0.20 0.64 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 1 120194.xlsm Version 10.5, November 2018 4/7/2022, 12:02 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 1 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.64 4 Area A (Acres) 0.67 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 1,485 ft3 Link to: LQV QV TR55 u 6 Length of Swale 45 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 3.00 ft 9 Set Swale Bottom Width b 9.78 ft 10 Set Swale Top Width ft 11 Set Swale Depth y 2.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 35.56 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 1,600 ft3 15 Does it Have Capacity? OK 16 Time to Drain 44.0 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (1,485.1) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 1 120194.xlsm 4/7/2022, 12:34 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 2 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i Qp-k 2.58 0.96 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 1,284 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 803 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cis 13 Volume Summary Surface Storage: Basin Basin Forebay V 128 ft' Primary Treatment/StorageBasin V 1,156 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 1,284 ft" Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 8,630 4,914 3,191 3,041 5,008 0.57 0.95 0.45 0.20 0.95 0.45 0.65 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients " Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 3 120194.xlsm Version 10.5, November 2018 4/7/2022, 12:43 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 2 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.65 4 Area A (Acres) 0.57 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 1,284 ft3 Link to: LQV QV TR55 u 6 Length of Swale 27 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 4.00 ft 9 Set Swale Bottom Width b 25.98 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 1.50 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 47.97 ft2 z Axs=y z+by 14 Total Swale Capacity Without Driveways 1,295 ft3 15 Does it Have Capacity? OK 16 Time to Drain 47.6 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (1,284.5) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 3 120194.xlsm 4/7/2022, 12:45 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 3 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 1.28 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 1,715 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 1,072 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 171 ft' Primary Treatment/StorageBasin V 1,543 ft- Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 1,715 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 8,564 7,421 3,154 6,757 6,865 0.75 0.95 0.45 0.20 0.95 0.45 0.66 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 4120194.xlsm Version 10.5, November 2018 4/7/2022, 12:51 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 3 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.66 4 Area A (Acres) 0.75 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 1,715 ft3 Link to: LQV QV TR55 u 6 Length of Swale 21 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 3.00 ft 9 Set Swale Bottom Width b 62.80 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 1.25 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 84.75 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 1,780 ft3 15 Does it Have Capacity? OK 16 Time to Drain 46.7 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (1,714.8) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 4 120194.xlsm 4/7/2022, 12:56 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 4 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (i) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) Qp-k iP254 n/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 159 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cis 13 Volume Summary Surface Storage: Basin Basin Forebay V 25 ft' Primary Treatment/StorageBasin V 229 ft- Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 254 ft" Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 2,976 0 1,873 0.11 0.95 0.45 0.20 0.66 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients " Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. eep:>6% 0.13 0.18 0.23 O. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 6a 120194.x1sm Version 10.5, November 2018 4/7/2022, 1:13 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 4 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.66 4 Area A (Acres) 0.11 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 254 ft3 Link to: LQV QV TR55 u 6 Length of Swale 4 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 3.00 ft 9 Set Swale Bottom Width b 50.00 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 1.25 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 68.75 ft2 z Axs=y z+by 14 Total Swale Capacity Without Driveways 275 ft3 15 Does it Have Capacity? OK 16 Time to Drain 36.3 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (254.0) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 6a 120194.xlsm 4/7/2022, 1:15 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 5 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) Qp-k iV95th in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 118 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cis 13 Volume Summary Surface Storage: Basin Basin Forebay V 19 ft' Primary Treatment/StorageBasin V 171 ft- Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 190 ft" Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 2,180 0 1,592 0.09 0.95 0.45 0.20 0.63 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients " Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. eep:>6% 0.13 0.18 0.23 O. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 6b 120194.xlsm Version 10.5, November 2018 4/7/2022, 1:41 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 5 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.63 4 Area A (Acres) 0.09 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 190 ft3 Link to: LQV QV TR55 u 6 Length of Swale 5 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 2.00 ft 9 Set Swale Bottom Width b 27.00 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 1.25 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 40.00 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 200 ft3 15 Does it Have Capacity? OK 16 Time to Drain 32.5 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (189.5) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 6b 120194.xlsm 4/7/2022, 1:43 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 6 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user cakuiata min to Min. 8 Determine the average rainfall intensity (i) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) Qp-k iP357 n/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 223 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cis 13 Volume Summary Surface Storage: Basin Basin Forebay V 36 ft' Primary Treatment/StorageBasin V 321 ft- Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 357 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 2,825 0 9,084 0.27 0.95 0.45 0.20 0.38 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 8120194.xlsm Version 10.5, November 2018 4/7/2022, 1:50 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 6 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.38 4 Area A (Acres) 0.27 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 357 ft3 Link to: LQV QV TR55 u 6 Length of Swale 4 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 4.00 ft 9 Set Swale Bottom Width b 27.00 ft 10 Set Swale Top Width 30.00 ft 11 Set Swale Depth y 2.50 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 92.50 ft2 z Axs=y z+by 14 Total Swale Capacity Without Driveways 370 ft3 15 Does it Have Capacity? OK 16 Time to Drain 38.3 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (357.1) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 8 120194.xlsm 4/7/2022, 1:51 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 7 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 1.06 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 1,422 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) V„ 889 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 142 ft' Primary Treatment/StorageBasin V 1,280 ft- Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 1,422 ft" Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 14,307 6,002 8,142 0.65 0.95 0.45 0.20 0.63 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 7120194.xlsm Version 10.5, November 2018 4/7/2022, 1:55 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 7 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.63 4 Area A (Acres) 0.65 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 1,422 ft3 Link to: LQV QV TR55 u 6 Length of Swale 11 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 5.00 ft 9 Set Swale Bottom Width b 62.90 ft 10 Set Swale Top Width 18.00 ft 11 Set Swale Depth y 2.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 141.80 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 1,560 ft3 15 Does it Have Capacity? OK 16 Time to Drain 44.3 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (1,421.8) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 7 120194.xlsm 4/7/2022, 1:57 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 8 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (ClPeak) i Qpeak 2.58 1.98 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 2,647 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) V„ 1,655 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 265 ft' Primary Treatment/StorageBasin V 2,383 ft" Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 2,647 ft- Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 12,185 0 15,757 14,555 9,854 1,889 1.25 0.95 0.45 0.20 0.95 0.45 0.20 0.62 Estimated Runoff Coefficients for Various Surfao Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential rural 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>61% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 9120194.xlsm Version 10.5, November 2018 4/7/2022, 2:03 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 8 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.62 4 Area A (Acres) 1.25 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 2,647 ft3 Link to: LQV QV TR55 u 6 Length of Swale 10 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 10.00 ft 9 Set Swale Bottom Width b 137.00 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 2.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 290.00 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 2,900 ft3 15 Does it Have Capacity? OK 16 Time to Drain 45.4 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (2,647.2) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 9 120194.xlsm 4/7/2022, 2:04 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 9 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (ClPeak) i Qpeak 2.58 1.76 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 2 354 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) V„ 1,471 ft,12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 235 ft' Primary Treatment/StorageBasin V 2,119 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 2,354 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 23,311 4,491 27,525 1.27 0.95 0.45 0.20 0.54 Estimated Runoff Coefficients for Various Surfao Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential rural 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>61% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 12 120194.x1sm Version 10.5, November 2018 4/7/2022, 4:50 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 9 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.54 4 Area A (Acres) 1.27 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 2,354 ft3 Link to: LQV QV TR55 u 6 Length of Swale 50 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 4.00 ft 9 Set Swale Bottom Width b 21.57 ft 10 Set Swale Top Width 24.00 ft 11 Set Swale Depth y 1.75 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 50.00 ft2 z Axs=y z+by 14 Total Swale Capacity Without Driveways 2,500 ft3 15 Does it Have Capacity? OK 16 Time to Drain 47.1 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (2,354.1) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 12 120194.xlsm 4/7/2022, 4:53 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 10 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (ClPeak) i Qpeak 2.58 1.53 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 2,056 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) V„ 1,285 ft, 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 206 ft' Primary Treatment/StorageBasin V 1,850 ft- Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 2,056 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 16,020 5,964 40,044 1.42 0.95 0.45 0.20 0.42 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 14120194.x1sm Version 10.5, November 2018 4/7/2022, 5:00 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 10 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.42 4 Area A (Acres) 1.42 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 2,056 ft3 Link to: LQV QV TR55 u 6 Length of Swale 15 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 5.00 ft 9 Set Swale Bottom Width b 144.35 ft 10 Set Swale Top Width 2.00 ft 11 Set Swale Depth y 1.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 148.35 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 2,225 ft3 15 Does it Have Capacity? OK 16 Time to Drain 47.0 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (2,055.8) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 14 120194.xlsm 4/7/2022, 5:02 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 11 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 0.84 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 1,130 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 706 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 113 ft' Primary Treatment/StorageBasin V 1,017 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 1,130 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 11,517 2,954 9,836 0.56 0.95 0.45 0.20 0.59 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 13 120194.x1sm Version 10.5, November 2018 4/7/2022, 5:08 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 11 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.59 4 Area A (Acres) 0.56 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 1,130 ft3 Link to: LQV QV TR55 u 6 Length of Swale 25 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 4.00 ft 9 Set Swale Bottom Width b 18.95 ft 10 Set Swale Top Width 22.00 ft 11 Set Swale Depth y 1.75 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 45.41 ft2 2 Axs=y z+by 14 Total Swale Capacity Without Driveways 1,135 ft3 15 Does it Have Capacity? OK 16 Time to Drain 45.2 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (1,129.6) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 13 120194.xlsm 4/7/2022, 5:10 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 12 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 25 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (ClPeak) i Qp-k 1.85 0.63 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 846 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 736 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cis 13 Volume Summary Surface Storage: Basin Basin Forebay V 85 ft' Primary Treatment/StorageBasin V 762 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 846 ft- Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 10,689 9,723 1,571 0.50 0.95 0.45 0.20 0.68 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 15 120194.x1sm Version 10.5, November 2018 4/7/2022, 5:15 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 12 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 25 Weighted Runoff Coefficient C 0.68 4 Area A (Acres) 0.50 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 846 ft3 Link to: LQV QV TR55 u 6 Length of Swale 40 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 2.50 ft 9 Set Swale Bottom Width b 27.74 ft 10 Set Swale Top Width 2.00 ft 11 Set Swale Depth y 1.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 31.74 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 1,270 ft3 15 Does it Have Capacity? OK 16 Time to Drain 33.9 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (846.5) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 15 120194.xlsm 4/7/2022, 5:19 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 13 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 2.63 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 3,521 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 2,201 fY 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 352 ft' Primary Treatment/StorageBasin V 3,169 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 3,521 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 18,257 1,529 0 15,902 10,116 33,442 1.82 0.95 0.45 0.20 0.95 0.45 0.20 0.56 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 16 120194.x1sm Version 10.5, November 2018 4/7/2022, 5:26 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 13 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.56 4 Area A (Acres) 1.82 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 3,521 ft3 Link to: LQV QV TR55 u 6 Length of Swale 30 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 10.00 ft 9 Set Swale Bottom Width b 117.00 ft 10 Set Swale Top Width 2.00 ft 11 Set Swale Depth y 1.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 121.00 ft' z Axs=y z+by 14 Total Swale Capacity Without Driveways 3,630 ft3 15 Does it Have Capacity? OK 16 Time to Drain 46.9 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (3,521.1) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 16 120194.xlsm 4/7/2022, 5:27 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 14 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 2.36 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 3,155 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr 1,972 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 315 ft' Primary Treatment/StorageBasin V 2,839 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 3,155 ft` Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 24,256 23,057 31,727 1.81 0.95 0.45 0.20 0.50 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 11 120194.x1sm Version 10.5, November 2018 4/7/2022, 5:33 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 14 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.50 4 Area A (Acres) 1.81 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 3,155 ft3 Link to: LQV QV TR55 u 6 Length of Swale 55 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 3.00 in/hr 8 Infiltration Window Width 5.00 ft 9 Set Swale Bottom Width b 22.00 ft 10 Set Swale Top Width 18.00 ft 11 Set Swale Depth y 2.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 60.00 ft2 z Axs=y z+by 14 Total Swale Capacity Without Driveways 3,300 ft3 15 Does it Have Capacity? OK 16 Time to Drain 45.9 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (3,154.9) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 11 120194.xlsm 4/7/2022, 5:34 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 15 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 3.21 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 4,301 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) V„ 2,688 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 430 ft' Primary Treatment/StorageBasin V 3,871 ft' Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 4,301 ft' Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 28,844 29,408 67,895 2.90 0.95 0.45 0.20 0.43 Estimated Runoff Coefficients for Various Surfac Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential (rural) 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-OAO Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 1 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>6% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 10 120194.x1sm Version 10.5, November 2018 4/7/2022, 5:39 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 15 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.43 4 Area A (Acres) 2.90 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 4,301 ft3 Link to: LQV QV TR55 u 6 Length of Swale 16 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 10.00 ft 9 Set Swale Bottom Width b 176.30 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 1.50 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 273.45 ft2 z Axs=y z+by 14 Total Swale Capacity Without Driveways 4,375 ft3 15 Does it Have Capacity? OK 16 Time to Drain 46.1 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (4,301.3) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 10 120194.xlsm 4/7/2022, 5:40 PM Version 10.0, May 2018 ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. Steps for Peak Discharge Rate using the Rational Method calculated for post -development _ Calculate Post -Development Flows (for pre -development flows, increase number of storage facilities to create new tab) User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 16 2 Is area drainage basin map provided? YES (map must be included with stormwater calculations) 3 Enter Design Storm (100-Year or 25-Year With 100-Year Flood Route) 100 4 Enter number of storage facilities (25 max) 1 Click to Show More Subbasins ❑ 5 Area of Drainage Subbasin (SF or Acres) SF Acre 6 Determine the Weighted Runoff Coefficient (C) C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avg 7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 user calculate min to Min. 8 Determine the average rainfall intensity (1) from IDF Curve based on Tc 9 Calculate the Post -Development peak discharge (QPeak) i QPeak 2.58 3.29 in/hr cfs 10 Calculate total runoff vol (V) (for sizing primary storage) V 4,406 ft V = Ci (Tc=60)Ax3600 11 Calculate Volume of Runoff Reduction Vrr Enter Percentile Storm I (95th percentile = 0.60 in) 95th 0.60 in Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) V„ 2,754 ft 12 Detention: Approved Discharge Rate to Surface Waters (if applicable) cfs 13 Volume Summary Surface Storage: Basin Basin Forebay V 441 ft' Primary Treatment/StorageBasin V 3,966 ft" Subsurface Storage Volume Without Sediment Factor (See BMP 20 Tab) V 4,406 ft- Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin Subbasin 1 Subbasin 2 3 4 5 Subbasin 6 7 8 9 10 16,781 16,907 44,843 15,420 15,310 7,391 2.68 0.95 0.45 0.20 0.95 0.45 0.20 0.48 Estimated Runoff Coefficients for Various Surfao Type of Surface Runoff Coefficients "I Business Downtown areas 0.70-0.95 Urban neighborhoods 0.50-0.70 Residential Single Family 0.35-0.50 Multi -family 0.60-0.75 Residential rural 0.25-0.40 Apartment Dwelling Areas 0.70 Industrial and Commercial Light areas 0.80 Heavy areas 0.90 Parks, Cemeteries 0.10-0.25 Playgrounds 0.20-0.35 Railroad yard areas 0.20-0.40 Unimproved areas 0.10-0.30 Streets Asphalt 0.95 Concrete 0.95 Brick 0.95 Roofs 0.95 Gravel 0.75 Fields: Sandy soil Soil Type Slope A B C D Flat: 0-2% 0.04 0.07 0.11 0. Average: 2-6% 0.09 0.12 0.15 0. Steep:>61% 0.13 0.18 0.23 0. Adapted from ASCE G:\2020\120194\CAD\Calcs and Reports\Storm\ACHD Storm Calcs\211013 ACHD Calcs - Bioswale 5 120194.xlsm Version 10.5, November 2018 4/7/2022, 5:45 PM ACHD Calculation Sheet for Sizing Bioswales & Borrow Ditches NOTE: This worksheet is intended to be a guideline to standardize ACHD checking of drainage calculations and shall not replace the Engineer's calculation methodology. These calculations shall establish a minimum requirement. The Engineer's methodology must result in facilities that meet or exceed these calculations in order to be accepted. User input in yellow cells. 1 Project Name Aviator Springs - Infiltration Basin 16 2 Enter number of Bioswales/Borrow Ditches (25 max) 1 3 Design Storm 100 Weighted Runoff Coefficient C 0.48 4 Area A (Acres) 2.68 acres Approved discharge rate for the given storm (if applicable) 0.00 cfs 5 Design Vol With 0% Sed for Swales V 4,406 ft3 Link to: LQV QV TR55 u 6 Length of Swale 16 ft 7 Infiltration Window? (Note: infiltration required if Longitudinal Slope<1%) Design Infiltration Rate 7.00 in/hr 8 Infiltration Window Width 10.00 ft 9 Set Swale Bottom Width b 138.88 ft 10 Set Swale Top Width 20.00 ft 11 Set Swale Depth y 2.00 ft 12 Swale Side Slopes H:1 Sxs 4.00 13 Calculate cross -sectional area Axs 293.76 ft2 2 Axs=y z+by 14 Total Swale Capacity Without Driveways 4,700 ft3 15 Does it Have Capacity? OK 16 Time to Drain 47.2 hr 90%volume in 48-hours minimum OK Check Swale With Driveways 17 Avg. Driveway Fill Slope in Swale (H/V) ft/ft 18 Enter Total Number of Driveways ea 19 Enter Total Length of all Driveways ft 20 Lost Swale Length From Trees, etc. ft 21 Adjusted Length of Infiltration Area 0.0 ft 22 Excess Capacity = Storage - Deductions - Runoff Volume (4,406.1) ft3 23 Is Capacity Good? 24 Time to Drain 0.0 hr 90% volume in 48-hours minimum OK 0.0 ft3 Deduct driveway slope 0.0 ft3 Deduct driveway length 0.0 ft3 Deduct other Note: Actual basin dimensions differ from the values listed above. Values in the spreadsheet have been calculated to represent an equivalent basin volume and infiltration window area. G:\2020\120194\CAD\Calcs and Repo rts\Sto rm\AC H D Storm Calcs\211013 ACHD Calcs - Bioswale 5 120194.xlsm 4/7/2022, 5:52 PM Version 10.0, May 2018 Aviator Springs Subdivision Meridian, ID Storm Water Management Report Appendix c Project Geotechnical Report and Ground Water Monitoring fhelandgroupinc com GEOTECHNICAL EVALUATION FOR "SKY PILOT SUBDIVISION" — A 38+ ACRE RESIDENTIAL DEVELOPMENT LOCATED WEST OF NORTH MCDERMOTT ROAD AND WEST BECKY DRIVE INTERSECTION, MERIDIAN, IDAHO April 20, 2021 GTI-Project No. 2240-ID Prepared For: LASHER ENTERPRISES 3327 N Eagle Road Meridian, ID 83642 GeoTek, Inc. TABLE OF CONTENTS SCOPE OF SERVICES.......................................................................................................................................... I SITE DESCRIPTION............................................................................................................................................. 2 PROPOSED DEVELOPMENT............................................................................................................................2 FIELDSTUDIES......................................................................................................................................................2 REGIONAL GEOLOGY......................................................................................................................................2 SITESOILS.............................................................................................................................................................. 3 ArtificialFill......................................................................................................................................................3 NativeAlluvial Soils........................................................................................................................................ 3 SURFACE & GROUND WATER......................................................................................................................4 TECTONIC FAULTING AND REGIONAL SEISMICITY............................................................................4 Secondary Seismic Constraints.................................................................................................................... 4 Summary: .......................................................................................................................................................... 4 RESULTS OF LABORATORY TESTING.........................................................................................................5 CONCLUSIONS................................................................................................................................................... 5 RECOMMENDATIONS - EARTHWORK CONSTRUCTION................................................................. 5 General............................................................................................................................................................. 5 Demolition....................................................................................................................................................... 5 Removals/Processing - General................................................................................................................... 6 TransitionalPads.............................................................................................................................................6 ExcavationDifficulty.......................................................................................................................................6 FillPlacement...................................................................................................................................................7 ImportMaterial............................................................................................................................................... 7 Observationand Testing............................................................................................................................... 7 GroundWater................................................................................................................................................ 7 EarthworkSettlements.................................................................................................................................. 8 RECOMMENDATIONS — FOUNDATIONS.................................................................................................8 General............................................................................................................................................................. 8 Conventional Foundation Recommendations..........................................................................................9 FoundationSettlement................................................................................................................................ 10 PAVEMENT SECTIONS.................................................................................................................................... 10 Pavement Construction and Maintenance.............................................................................................. 10 OTHER RECOMMENDATIONS.................................................................................................................... SiteImprovements........................................................................................................................................ Landscape Maintenance and Planting........................................................................................................ GeoTek, Inc. SoilCorrosion............................................................................................................................................... 12 TrenchExcavation........................................................................................................................................ 12 Onsite Utility Trench Backfill..................................................................................................................... 12 Drainage.......................................................................................................................................................... 12 PLANREVIEW.....................................................................................................................................................13 LIMITATIONS...................................................................................................................................................... 13 Enclosures: Figure # I , Site Vicinity Map Figure #2, Site Exploration Plan Appendix A, References Appendix B, Test Pit Logs Appendix C, Field Test Results Appendix D, Laboratory Test Results GeoTek, Inc. GeoTek, Inc. 320 East Corporate Drive Suite 300 Meridian, ID 83642-351 1 (208) 888-7010 (208) 888-7924 www.geotekusa.com April 20, 2021 Project No. 2240-ID Lasher Enterprises 3327 N. Eagle Road, Ste. 1 10-135 Meridian, ID 83642 Attention: Mr. Brady Lasher Subject: Geotechnical Evaluation for "Sky Pilot Subdivision" — a 38± Acre Residential Development — Located West of North McDermott Road and West Becky Drive Intersection, Meridian, Idaho Dear Mr. Lasher, In accordance with your request, GeoTek, Inc. (GTI) has completed a geotechnical evaluation of the subject property for the construction of a single-family residential development with associated improvements. The purpose of our study was to evaluate the soils underlying the site and to provide recommendations for project design and construction based on our findings. This report outlines the geologic and geotechnical conditions of the site based on current data and provides earthwork and construction recommendations with respect to those conditions. SCOPE OF SERVICES The scope of our services has included the following: I . Review of soils and geologic reports and maps for the site (Appendix A) 2. Site reconnaissance 3. Review of aerial photographs 4. Excavating and logging of sixteen (16) exploratory test pits (Appendix B) 5. Obtaining samples of representative soils, as the exploratory test pits were advanced 6. Performing laboratory testing on representative soil samples (Appendix D) 7. Assessment of potential geologic constraints 8. Engineering analysis regarding foundation design/construction, foundation settlement, and site preparation 9. Preparation of this report GEOTECHNICAL I ENVIRONMENTAL I MATERIALS SKY PILOT SUBDIVISION LASHER ENTERPRISES PROJECT NO. 2240-ID SITE DESCRIPTION APRIL 20, 2021 PAGE 2 The project site consists of an irregularly shaped parcel totaling approximately 38± acres that is generally bound by vacant agricultural land and a single-family home to the north, North McDermott Road and single-family homes to the east, the Eightmile Lateral and vacant agricultural land to the south, and a high school and residential development (currently under construction) to the west (Figures I and 2). Currently, the property consists of farmland that has been corrugated/irrigated for crop farming purposes over many years. The Eightmile Lateral bisects the southeast corner of the site. Access to the site is currently possible from North McDermott Road. From topographic maps, the site's elevation is approximately 2,520± feet to 2,535± feet above mean sea level. Historically, topography generally directs surface water to the west-northwest. PROPOSED DEVELOPMENT It is our understanding that site development would consist of performing typical cut and fill earthwork to attain the desired graded configuration(s) for the construction of a residential subdivision of one- to two-story detached single-family residential structures with associated improvements. It is further assumed that final site grade will be within 5 feet of existing site grade. FIELD STUDIES Subsurface conditions at the site were explored by using a rubber -tired backhoe. Sixteen (16) test pits were advanced onsite. A log of each exploration is included within this report in Appendix B. Seven (7) percolation tests were performed on the subject site as well as seven (7) initial ground water measurements (Appendix C). Field studies were completed during March of 2021 by field personnel who conducted field excavation location mapping, logged the excavations, and obtained samples of representative soils for laboratory testing. The approximate locations of the explorations are indicated on the enclosed Site Exploration Plan (Figure 2). The Unified Soil Classification System (USCS) was used to visually classify the subgrade soils during the field exploration. REGIONAL GEOLOGY The subject site is situated within the Boise River Valley, which comprises the northwestern portion of the Snake River Plain physiographic province. The western portion of the Snake River Plain is aligned in a northwest -southeast direction and generally divides the Owyhee mountains to the south from the Central Idaho mountains toward the north (Wood and Clemens, 2004). The headwaters of the Boise River are located in the Central Idaho mountains east of Boise, Idaho. The river leaves the central mountains and enters the Snake River Plain near Barber and drains toward the west into the Snake River near Parma. The Owyhee mountains and the Central Idaho Mountains are composed predominantly of volcanic and igneous rocks. The western portion of the Snake River Plain is a northwest trending complex graben formed by extension and regional uplift along the northern boundary of the basin and range province (Wood and Clemens, 2004). The graben generally forms a basin which has been partially filled with younger sedimentary and volcanic rocks (Malde, 1991). GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 3 PROJECT NO. 2240-ID The Boise River Valley is bounded on the northeast by the Boise Front, which is a northwest trending topographic high extending generally from Boise to Emmett, Idaho. The Boise Front consists of Cretaceous aged granitic and metamorphic rocks cut by Tertiary aged rhyolite and overlain with Miocene aged lake sediments (Wood and Clemens, 2004). These units have been cut by northwest trending faults which down drop these units toward the southwest. The faults also provide conduits for Quaternary aged basalt intrusions and flows (Malde, 1991). The depositional environment for the valley floor is dominantly lake laid deposits of sand, silt and clay. These materials were deposited during two periods of lake activity, one during the Miocene and the other during the Pleistocene. This valley infilling process has been subsequently truncated by down faulting within the valley ranging in height from a few feet to over 50 feet. Younger alluvium has been, and continues to be, transported dominantly by water and deposited on the basins gently sloping valley floor and within low-level flood plains. Portions of the alluvial deposits are being down cut by intermittent streams to the flood plain, and as a result stream terraces are being formed. SITE SOILS Artificial Fill Based on our field studies, some spread fills were observed along the perimeter of the site and on the interior maintenance roadways. This fill is generally associated with the construction of the roadways and irrigation laterals. This spread fill shall be considered artificial fill. The majority of the property has been cultivated for agricultural use, the upper 12 inches of material has been disturbed and consists of silts with a moderate amount of organics and roots. This shall be considered artificial fill. Deeper fills may be encountered onsite. The "Artificial Fills" are soft, contain organics/roots and are not considered suitable for support of foundations. All artificial fill material should be removed as described in the "Removals" section of this report. Native Alluvial Soils Alluvial soils encountered generally consist of surficial layers of silty sands and silts with varying amounts of sand, underlain by poorly graded sands and poorly graded gravels with sand and cobbles. The moisture content within the alluvial materials was generally moist to saturated at depth. The consistency of these soils ranged from firm/medium dense near surface and medium dense to dense at depth. Partially cemented layers of material were encountered in some of our excavations; however, we anticipate that the onsite soils can be excavated with conventional earthwork equipment equivalent to CAT D9R dozers and CAT 235 excavators. Special excavation equipment and techniques may be necessary dependent upon if harder materials are encountered during construction. After the upper 12 inches of artificial fill is removed, the underlying 12 inches of the native alluvium soil will require, at a minimum, some removal and/or processing efforts to be considered suitable for the support of the proposed site improvements. Locally deeper processing/removals may be necessary. Refer to the "Recommendations Earthwork Construction" section of this report for specific site preparation recommendations. GeoTek, Inc. SKY PILOT SUBDIVISION LASHER ENTERPRISES PROJECT NO. 2240-ID SURFACE & GROUND WATER APRIL 20, 2021 PAGE 4 Ground water was encountered in the majority of our excavations. Ground water depths ranged from a depth of 8.7 to 12.8 feet below approximate existing grade in test pits TPA and TP-14, respectively. Irrigation ditches exist on the interior, and adjacent to, the site and they transmit water on a periodic basis. Generally, irrigation ditches and canals will locally influence ground water during the irrigation season (i.e., May through October). If encountered, wet materials should be spread out and air-dried or mixed with drier soils to reduce their moisture content as appropriate for fill placement. Ground water is not anticipated to adversely affect planned development, provided that earthwork construction methods comply with recommendations contained in this report or those made subsequent to review of the improvement plan(s). GTI assumes that the design civil engineer of record will evaluate the site for potential flooding and set grades such that the improvements are adequately protected. These observations reflect conditions at the time of this investigation and do not preclude changes in local ground water conditions in the future from natural causes, damaged structures (lines, pipes etc.), or heavy irrigation. TECTONIC FAULTING AND REGIONAL SEISMICITY The site is situated in an area of active as well as potentially active tectonic faults, however no faults were observed during our field evaluation. There are a number of faults in the regional area, which are considered active and would have an affect on the site in the form of ground shaking, should they be the source of an earthquake. It is reasonable to assume that structures built in this area will be subject to at least one seismic event during their life, therefore, it is recommended that all structures be designed and constructed in accordance with the International Building Code (IBC). Based on our experience in the general vicinity, references in our library, field evaluation of the site, a Seismic Design Site Class Designation of `D' may be used for seismic design. Secondary Seismic Constraints The following list includes other potential seismic related hazards that have been evaluated with respect to the site, but in our opinion, the potential for these seismically related constraints to affect the site is considered negligible. * Liquefaction * Dynamic Settlements * Surface Fault Rupture * Ground Lurching or Shallow Ground Rupture Summary It is important to keep in perspective that if a seismic event were to occur on any major fault, intense ground shaking could be induced to this general area. Potential damage to any settlement sensitive structures would likely be greatest from the vibrations and impelling force caused by the inertia of the structures mass than that created from secondary seismic constraints. Considering the subsurface soil conditions and local seismicity, it is estimated that the site has a low risk associated with the potential for these phenomena to occur and adversely affect surface improvements. These potential risks are no greater at this site than they are for other structures and improvements developed on the alluvial materials in this vicinity. GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 5 PROJECT NO. 2240-ID RESULTS OF LABORATORY TESTING Laboratory tests were performed on representative samples of the onsite earth materials in order to evaluate their physical and chemical characteristics. The tests performed, and the results obtained are presented in Appendix D. CONCLUSIONS Based on our field exploration, laboratory testing and engineering analyses, it is our opinion that the subject site is suited for development from a geotechnical engineering viewpoint. The recommendations presented herein should be incorporated into the final design, grading, and construction phases of development. The engineering analyses performed concerning site preparation and the recommendations presented below have been completed using the information provided to us regarding site development. In the event that the information concerning proposed development is not correct, the conclusion and recommendations contained in this report shall not be considered valid unless the changes are reviewed, and conclusions of this report are modified or approved in writing by this office. RECOMMENDATIONS - EARTHWORK CONSTRUCTION General All grading should conform to the International Building Code (IBC) and the requirements of the City of Meridian, except where specifically superseded in the text of this report. During earthwork construction all removals, drain systems, slopes, and the general grading procedures of the contractor should be observed and the fill selectively tested. If unusual or unexpected conditions are exposed in the field, they should be reviewed by this office and, if warranted, modified and/or additional recommendations will be offered. It is recommended that the earthwork contractor(s) perform their own independent reconnaissance of the site to observe field conditions firsthand. If the contractor(s) should have any questions regarding site conditions, site preparation, or the remedial recommendations provided, they should contact an engineer at GeoTek for any necessary clarifications prior to submitting earthwork bids. All applicable requirements of local and national construction and general industry safety orders, the Occupational Safety and Health Act, and the Construction Safety Act should be met. Demolition The following recommendations are provided encountered that are not intended to remain. as guidelines in the event that structures are 1. All existing surface or subsurface structures (not intended to remain), within the area to be developed, should be razed and moved off site. 2. If a septic tank (to be abandoned or below a proposed improvement) is located within the project site, it is recommended that it be pumped out and, with few exceptions, likely GeoTek, Inc. SKY PILOT SUBDIVISION LASHER ENTERPRISES PROJECT NO. 2240-ID APRIL 20, 2021 PAGE 6 removed. Any leach lines, seepage pits, or other pipes associated with this structure should also be removed or properly abandoned. 3. If any wells are encountered, an attempt should be made to identify the owner and purpose of the well. Well abandonment should adhere to the recommendations provided by the Idaho Department of Water Resources, the Public Health Department, or any other government agencies. If the well is located in the area of a proposed structure, these recommendations should be reviewed by GTI and, if warranted, additional geotechnical recommendations will be offered. Removals/Processing - General Presented below are removal/processing recommendations for the various soils encountered on the project. Debris, vegetation, and other deleterious material should be stripped/removed from areas proposed for structural improvements. Based on a review of the exploratory logs and our site reconnaissance, after the artificial fill and deleterious material are removed, a minimum removal/processing depth of 12 inches into alluvial materials should be accomplished across the site. If the left in place soils can be scarified to encounter a competent layer below; they may be processed in place; otherwise, they should be removed to competent material. Locally deeper removals/processing may be necessary based on the field conditions exposed. Since much of the site has been disturbed, it should be anticipated that deeper fills may be encountered onsite. Beneath foundations and slab areas, the exposed ground surface should be moisture conditioned and compacted a minimum of 12 inches to provide a more uniform foundation support. A minimum relative compaction of 90 percent of the laboratory maximum modified density (ASTM D 1557) at moisture content of optimum or above is necessary to generate any near surface settlements. Locally deeper removals/processing may be necessary based on the conditions exposed. Removal bottoms should be checked by a representative of GeoTek, Inc. to see if deeper removals are necessary. If existing improvements or property line restrictions limit removals, condition specific recommendations would be provided on a case -by -case basis. During earthwork construction, care should be taken by the contractor so that adverse ground movements or settlements are not generated affecting existing improvements. Transitional Pads Transitional pads are defined in this report as pads which are partially cut and partially fill. To mitigate some of the differential settlement which will occur on transitional pads, the cut side should be over- excavated/processed to a minimum depth equal to 2 feet below the bottom of the footings or to the depth of the fill, whichever is less. On transitional pads with more than 7.5 feet of fill, plans need to be reviewed by GTI and site -specific recommendations will be provided. Excavation Difficulty We anticipate that the onsite soils can be excavated with conventional earthwork. Seasonal conditions could cause wet soil conditions to occur onsite. Depending on the depth of cuts, it should be expected that special excavation and fill placement measures may be necessary. Wet materials should GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 7 PROJECT NO. 2240-ID be spread out and air-dried or mixed with drier soils to reduce their moisture content to the appropriate level for fill placement. Frozen soils, if encountered, should be removed and allowed to thaw prior to any fill placement or construction. Removal bottoms should be checked by a representative of GTI to see if deeper removals are necessary. Fill Placement Subsequent to completing removals/processing and ground preparation, the excavated onsite and/or imported soils may be placed in relatively thin lifts (less than 8 inches thick), cleaned of vegetation and debris, brought to at least optimum moisture content, and compacted to a minimum relative compaction of 90 percent of the laboratory standard (ASTM D 1557). Import Material Potentially, soils will be imported to the site for earthwork construction purposes. A sample of any intended import material should first be submitted to GTI so that, if necessary, additional laboratory or chemical testing can be performed to verify that the intended import material is compatible with onsite soils. In general, import material should be within the following minimum guidelines: * Free of organic matter and debris * Maintain less than 0.2 percent sulfate content * Maintain less than 3.0 percent soluble material * Maintain less than 0.02 percent soluble chlorides * Maintain less than 0.2 percent sodium sulfate content * Maintain a Plasticity Index less than 12 (i.e., low expansive) * One hundred percent passing the six-inch screen * At least seventy-five percent passing a three-inch screen * Maintain at least 20 percent on No. 4 screen * Maintain between 5 and 30 percent passing the No. 200 screen Observation and Testing During earthwork construction all removal/processing and the general grading procedures should be observed, and the fill selectively tested by a representative(s) of GTI. If unusual or unexpected conditions are exposed in the field, they should be reviewed by GTI and if warranted, modified and/or additional recommendations will be offered. Ground Water Ground water was encountered in the majority of our excavations. Ground water depths ranged from a depth of 8.7 to 12.8 feet below approximate existing grade in test pits TP-4 and TP-14, respectively. Based on site conditions in the future, a transient high ground water condition could develop over a clay or less permeable layer and this condition could generate down gradient seepage. The possible effect these layers could have on this and adjacent sites should be considered and can best be evaluated in the field during grading. If warranted by exposed field conditions, it may be recommended that a drainage system be established to collect and convey any subsurface water to an appropriate location for drainage. Typically, potential areas of seepage are difficult to identify prior to their occurrence; therefore, it is often best to adopt a "wait and see" approach to determine if any seepage conditions do develop, at which time specific recommendation to mitigate an identified condition can be provided. GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 8 PROJECT NO. 2240-ID Earthwork Settlements Ground settlement should be anticipated due to primary consolidation and secondary compression. The total amount of settlement and time over which it occurs is dependent upon various factors, including material type, depth of fill, depth of removals, initial and final moisture content, and in -place density of subsurface materials. Compacted fills, to the heights anticipated, are not generally prone to excessive settlement. However, some settlement of the left -in -place alluvium is expected, and the majority of this settlement is anticipated to occur during grading. Slope Sta4 tx No significantly high (greater than ten feet) slopes are anticipated to be constructed onsite. All slopes should be designed at gradients of 2 to I (Horizontal to Vertical) or flatter. All slopes should be constructed in accordance with the minimum requirements of the City of Meridian and the International Building Code. Cut and fill slopes are anticipated to perform adequately in the future with respect to gross and surficial stability if the soil materials are maintained in a solid to semi -solid state (as defined by the soils Atterberg Limits) and are limited to the heights prescribed herein. The importance of proper compaction to the face of a slope cannot be overemphasized. In order to achieve proper compaction, one or more of the three following methods should be employed by the contractor following implementation of typical slope construction guidelines: I) track walk the slopes at grade, 2) use a combination of sheep's -foot roller and track walking, or 3) overfill the slope 3 to 5 feet laterally and cut it back to grade. Random testing will be performed to verify compaction to the face of the slope. If the tests do not meet the minimum recommendation of 90 percent relative compaction, the contractor will be informed and additional compactive efforts recommended. A final evaluation of cut slopes during grading will be necessary in order to identify any areas of adverse conditions. The need for remedial stabilization measures should be based on observations made during grading by a representative of this office. Based on our observations, and if warranted, specific remedial recommendations will be offered for stabilization. The setback from the face of a structure and the toe of the graded slope should be at least the smaller of H/2 or 15 feet, where "H" is the height of the slope. RECOMMENDATIONS — FOUNDATIONS General Foundation design and construction recommendations are based on preliminary laboratory testing and engineering analysis performed on near surface soils. The proposed foundation systems should be designed and constructed in accordance with the guidelines contained herein and in the International Building Code. Based on our experience in the area, the soils onsite should have a negligible corrosive potential to concrete and metal, materials selected for construction purposes should be resistant to corrosion. Where permitted by building code, PVC pipe should be utilized. All concrete should be designed, mixed, placed, finished, and cured in accordance with the guidelines presented by the Portland Cement Association (PCA) and the American Concrete Institute (ACI). GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 9 PROJECT NO. 2240-ID Based on our grading recommendations, the soils beneath the foundations are anticipated to have low expansion potential. Therefore, foundation recommendations for low expansive soil conditions are provided below. If more expansive soils are encountered, the pad(s) will either need to be regraded and the more expansive soils removed by the contractor— or increased foundation recommendations will need to be provided. Conventional Foundation Recommendations Column loads are anticipated to be 50 kips or less while wall loads are expected to be 3 kips per linear foot or less. The conventional recommendations provided are from a geotechnical engineering perspective (i.e., for expansive conditions) and are not meant to supersede the design by the project's structural engineer. Preliminary recommendations for foundation design and construction are presented below. The specific criteria to be used should be verified on evaluation of the proposed buildings, structural loads, and expansion and chemical testing performed after grading is complete. The bearing values indicated are for the total dead, plus frequently applied, live loads and may be increased by one third for short duration loading which includes the effects of wind or seismic forces. When combining passive pressure and friction for lateral resistance, the passive component should be reduced by one-third. A grade beam, reinforced as below and at least 12 inches wide, should be utilized across all large entrances. The base of the grade beam should be at the same elevation as the bottom of the adjacent footings. Footings should be founded at a minimum depth of 24 inches below lowest adjacent ground surface as required by local codes to extend below the frost line. Reinforcement for spread footings should be designed by the project's structural engineer. For foundations systems including a crawl space, it is recommended that it be designed so that water is not allowed to penetrate the crawl space. Proper grading and backfill for the foundations are critical and should adhere to the "fill placement" and "drainage" recommendations of this evaluation as well as local building codes. Soil Minimum Allowable Passive Maximum Footing Expansion Footing Bearing Coefficient Earth Earth Type Classification Depth Pressure of Friction Pressure Pressure (inches) (psf) (psf/ft) (psf) Strip/Spread Low 24 2,000 0.35 250 3,000 The coefficient of friction and passive earth pressure values recommended are working values. Strip footings should have a minimum width of one foot and spread footings should have a minimum soil to concrete area of four -square feet. Increases are allowed for the bearing capacity of the footings at a rate of 250 pounds per square foot for each additional foot of width and 250 pounds per square foot for each additional foot of depth into the recommended bearing material, up to a maximum outlined. If the bearing value exceeds 3,000 psf, an additional review by GTI is recommended. As mentioned GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 10 PROJECT NO. 2240-ID earlier, the exposed ground surface should be moisture conditioned and compacted a minimum depth of 12 inches below bottom of footings. Foundation Settlement Provided that the recommendations contained in this report are incorporated into final design and construction phase of development, total settlement is estimated to be less than one inch and differential settlement is estimated to be less than 0.75 inches for a 25-foot span. Two-way angular distortions due to settlements are not estimated to exceed 1/400. The structures should be loaded uniformly so as to avoid any localized settlements. PAVEMENT SECTIONS Pavement sections presented in the following table are based on an R-value result of 8 and estimated traffic index(s) for residential construction. These pavement sections are presented for planning purposes only and should be verified based on specific laboratory testing performed subsequent to rough grading of the site. Pavement Construction and Maintenance All section changes should be properly transitioned. If adverse conditions are encountered during the preparation of subgrade materials, special construction methods may need to be employed. All subgrade materials should be processed to a minimum depth of 12 inches and compacted to a minimum relative compaction of 90 percent near optimum moisture content. All aggregate base should be compacted to a minimum relative compaction of 95 percent at optimum moisture content. The recommended pavement sections provided are meant as minimums. If thinner or highly variable pavement sections are constructed, increased maintenance and repair should be expected. If the ADT (average daily traffic) or ADTT (average daily truck traffic) increases beyond that intended, as reflected by the traffic index(s) used for design, increased maintenance and repair could be required for the pavement section. MINIMUM MINIMUM AGGREGATE ASPHALT THICKNESS (in.) ASSUMED TRAFFIC SUBGRADE Aggregate Subbase RIGHT -OF -AWAY R-VALUE CONCRETE THICKNESS Base (3/4" (Uncrushed (in•) minus)* Aggregate)* Residential Normal Traffic 8 23 4.0 12.0 TI = 6.0 Collector Normal Traffic 8 3.0 6.0 16.0 TI = 8.0 *Aggregate Base and Subbase gradation specification requirement per the current edition of the Idaho Standards for Public Works Construction (ISPWC) Manual. Asphalt mix design shall meet the requirements of ISPWC, Section 810 Class III Plant mix. Materials shall be placed in accordance with ISPWC Standard Specifications for Highway Construction. GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE I I PROJECT NO. 2240-ID Positive site drainage should be maintained at all times. Water should not be allowed to pond or seep into the ground. If planters or landscaping are adjacent to paved areas, measures should be taken to minimize the potential for water to enter the pavement section. OTHER RECOMMENDATIONS Site Improvements As is commonly known, expansive soils are problematic with respect to the design, construction and long-term performance of concrete flatwork. Due to the nature of concrete flatwork, it is essentially impossible to totally mitigate the effects of soil expansion. Typical measures to control soil expansion for structures include; low expansive soil caps, deepened foundation system, increased structural design, and soil presaturation. As they are generally not cost effective, these measures are very seldom utilized for flatwork because it's less costly to simply replace any damaged or distressed sections than to "structurally" design them. Even if "structural" design parameters are applied to flatwork construction, there would still be relative movements between adjoining types of structures and other improvements (e.g., curb and sidewalk). This is particularly true as the level of care during construction of flatwork is often not as meticulous as that for structures. Unfortunately, it is fairly common practice for flatwork to be poured on subgrade soils, which have been allowed to dry out since site grading. Generally, after flatwork construction is completed, landscape irrigation begins, utility lines are pressurized, and drainage systems are utilized; presenting the potential for water to enter the dry subgrade soils, causing the soil to expand. Recommendations for exterior concrete flatwork design and construction can be provided upon request. If, in the future, any additional improvements are planned for the site, recommendations concerning the geological or geotechnical aspects of design and construction of said improvements could be provided upon request. This office should be notified in advance of any fill placement, grading, or trench backfilling after rough grading has been completed. This includes any grading, utility trench and retaining wall backfills. Landscape Maintenance and Planting Water has been shown to weaken the inherent strength of all earth materials. Slope stability is significantly reduced by overly wet conditions. Graded slopes constructed within and utilizing onsite materials would be erosive. Eroded debris may be minimized, and surficial slope stability enhanced by establishing and maintaining a suitable vegetation cover as soon as possible after construction. Compaction to the face of fill slopes would tend to minimize short-term erosion until vegetation is established. Plants selected for landscaping should be lightweight, deep-rooted types, which require little water and are capable of surviving the prevailing climate. From a geotechnical standpoint leaching is not recommended for establishing landscaping. If the surface soils are processed for the purpose of adding amendments, they should be recompacted to 90 percent compaction. Only the amount of irrigation necessary to sustain plant life should be provided. Over watering the landscape areas could adversely affect proposed site improvements. We recommend that any proposed open bottom planter areas adjacent to proposed structures, be eliminated for a minimum distance of 5 feet and desert landscape using xeriscape technology be used outside of this buffer zone. As an alternative, closed bottom type planter could be utilized. An outlet, placed in the bottom of the planter, could be GeoTek, Inc. SKY PILOT SUBDIVISION APRIL 20, 2021 LASHER ENTERPRISES PAGE 12 PROJECT NO. 2240-ID installed to direct drainage away from structures or any exterior concrete flatwork. Irrigation timers should be adjusted on a monthly basis. Soil Corrosion Based on our experience in the area, the soils onsite should have a negligible corrosive potential to concrete and metal, materials selected for construction purposes should be resistant to corrosion. Where permitted by building code, PVC pipe should be utilized. All concrete should be designed, mixed, placed, finished, and cured in accordance with the guidelines presented by the Portland Cement Association (PCA) and the American Concrete Institute (ACI). Trench Excavation All footing trench excavations should be observed by a representative of this office prior to placing reinforcement. Footing trench spoil and any excess soils generated from utility trench excavations should be compacted to a minimum relative compaction of 90 percent if not removed from the site. Considering the nature of the onsite soils, it should be anticipated that caving or sloughing could be a factor in excavations. Shoring or excavating the trench walls and slopes to the angle of repose (typically 25 to 45 degrees) may be necessary and should be anticipated in non -cemented soils. All excavations should be observed by one of our representatives and conform to national and local safety codes. Onsite Utility Trench Backfill Considering the overall nature of the soil encountered onsite, it should be anticipated that materials will need to be imported to the site for use as pipe bedding and pipe zone material. All utility trench backfill should be brought to near optimum moisture content and then compacted to obtain a minimum relative compaction of 90 percent of the laboratory standard. Compaction testing and observation, along with probing should be performed to verify the desired results. Sand backfill, unless excavated from the trench, should not be used adjacent to perimeter footings or in trenches on slopes. Compaction testing and observation, along with probing should be performed to verify the desired results. Sand backfill, unless excavated from the trench, should not be used adjacent to perimeter footings or in trenches on slopes. Compaction testing and observation, along with probing should be performed to verify the desired results. Offsite utility trenches should be compacted to a minimum of 90 relative compaction. Compaction testing and observation, along with probing should be performed to verify the desired results. Drainage Positive site drainage should be maintained at all times in accordance with the IBC. Drainage should not flow uncontrolled down any descending slope. Water should be directed away from foundations and not allowed to pond and/or seep into the ground. Pad drainage should be directed toward the street or other approved area. The ground immediately adjacent to the foundation shall be sloped away from the building at a minimum of 5-percent for a minimum distance of 10 feet measured perpendicularly to the face of the wall. If physical obstructions prohibit 10 feet of horizontal distance, a 5-percent slope shall be provided to an approved alternate method of diverting water away from the foundation. Swales used for this purpose shall be sloped a minimum of 2-percent, where located within 10 feet of the building foundation. Impervious surfaces within 10 feet of the building foundation shall be sloped a minimum of 2-percent away from the building. Roof gutters and down spouts should be utilized to control roof drainage. Down spouts should outlet onto paved areas or a minimum of GeoTek, Inc. SKY PILOT SUBDIVISION LASHER ENTERPRISES PROJECT NO. 2240-ID APRIL 20, 2021 PAGE 13 five feet from proposed structures or into a subsurface drainage system. Areas of seepage may develop due to irrigation or heavy rainfall. Minimizing irrigation will lessen this potential. If areas of seepage develop, recommendations for minimizing this effect could be provided upon request. PLAN REVIEW Final grading, foundation, and improvement plans should be submitted to this office for review and comment as they become available, to minimize any misunderstandings between the plans and recommendations presented herein. In addition, foundation excavations and earthwork construction performed on the site should be observed and tested by this office. If conditions are found to differ substantially from those stated, appropriate recommendations would be offered at that time. LIMITATIONS The materials encountered on the project site and utilized in our laboratory study are believed representative of the area; however, soil materials vary in character between excavations and conditions exposed during mass grading. Site conditions may vary due to seasonal changes or other factors. GeoTek, Inc. assumes no responsibility or liability for work, testing, or recommendations performed or provided by others. Since our study is based upon the site materials observed, selective laboratory testing and engineering analysis, the conclusions and recommendations are professional opinions. These opinions have been derived in accordance with current standards of practice and no warranty is expressed or implied. Standards of practice are subject to change with time. The opportunity to be of service is greatly appreciated. If you have any questions concerning this report or if we may be of further assistance, please do not hesitate to contact the undersigned. Respectfully submitted, GeoTek, Inc. Steven J. Huber, El Staff Professional pxONAL r¢OQ � 4. 108 4 Lir IV C.41-2-o—Z1 David C. Waite, PE Senior Engineer GeoTek, Inc. -d 9 O The Oaks a QBetz Supply Inc iY fr�r.•r, L n an ITF JV111111Y VIVIIA W WlAdlan Rd W CMrry L n z eti 9 — 0 Sonna W FrairWin Rd N s N n k WIl Settlers Park f Wick Rd — z 2aa $ S S _ S Q a W CherryLn © The Human Bean W Pine Ave Meridian (Pn Avo W F—Win Rd (FranAlin Rd Geotek Insights Inc F A Wahooz Family Fun Zone - W Ore.Lm Rd N N D G1 APPROXIMATE SITE LOCATION Source: Google Maps 2021, GeoTek Field Observations, 2021. Not to Scale FIGURE I SITEVICINITY MAP Sky Pilot Subdivision West of N McDermott Rd & W Becky Dr G E O T E K Meridian, Idaho GEOTECHNICAL I ENVIRONMENTAL I MATERIALS Prepared for: Lasher Enterprises Project No.: Report Date: Drawn By: 320 E. Corporate Dr, Suite 300, Meridian, ID 83642 2240-ID April 2021 TSL (208) 888-7010 (phone) / (208) 888-7924 (FAX) APPROXIMATETEST PIT LOCATIONS Source: Google Earth 2018, GeoTek Field Observations, 2021. Not to Scale "r� G E O T E K GEOTECHNICAL I ENVIRONMENTAL I MATERIALS I Project No.: 320 E. Corporate Dr, Suite 300, Meridian, ID 83642 2240-1 D (208) 888-7010 (phone) 1 (208) 888-7924 (FAX) Report Date: Drawn By: April 2021 SJ H APPENDIX A GeoTek, Inc. REFERENCES Ada County Highway District Development Policy Manual, Revised by Resolution No. 690, October 2003 ASTM, 200, "Soil and Rock: American Society for Testing and Materials," vol. 4.08 for ASTM test methods D-420 to D-4914, 153 standards, 1,026 pages; and vol. 4.09 for ASTM test method D- 4943 to highest number. Breckinridge, R.M., Lewis, R.S., Adema, G.W., Weisz, D.W., 2003, Map of Miocene and Younger Faults in Idaho, Idaho Geological Survey, University of Idaho Collett, Russell A., 1980, Soil Survey of Ada County, Eastern Part, United States Department of Agriculture Soil Conversation Service, United States Department of the Interior Bureau of Land Management, Idaho Soil Conservation Commission, University of Idaho College of Agriculture. Day, Robert W., 1999, Geotechnical and Foundation Engineering — Design and Construction Day, Robert W., 2002, Geotechnical Earthquake Engineering Handbook GeoTek, Inc., In-house proprietary information. Idaho Department of Water Resources, Treasure Valley Hydrology — Geology, January 2003 Idaho Department of Water Resources, Well Information, Well Driller Reports, 2002 Idaho Transportation Department CD-ROM Publications, September 2003 Johnson, Bruce R. and Raines, Gary L., 1995, Digital representation of the Idaho state geologic map: a contribution to the Interior Columbia Basin Ecosystem Management Project. USGS Open -File Report 95-690 Malde, H.E., 1991. Quaternary geology and structural history of the Snake River Plain, Idaho and Oregon. In: The Geology of North America, Quaternary Nonglacial Geology: Conterminous U.S., Vol. K-2, 252-281 pp. Othberg, K.L., 1994. Geology and geomorphology of the Boise Valley and adjoining areas, western Snake River Plain, Idaho. Idaho Geological Survey Bulletin 29: 54 pp. USGS, Cloverdale Quadrangle, 7.5-Minute Series Topographic Map, 1979. USGS, 2003, Seismic Hazard Map of Idaho, Peak Acceleration (%g) with 2% Probability of Exceedance in 50 years. GeoTek, Inc. APPENDIX B GeoTek, Inc. LOG GENERAL NOTES CONSISTENCY OF FINE-GRAINED SOILS Unconfined Compressive Strength, Qu, psf Standard Penetration or N- Value (SS) Blows/Ft Consistency < 500 <2 Very Soft 500 - 1,000 2-3 Soft 1,001 - 2,000 4-7 Firm 2,001 - 4,000 8 - 16 Stiff 4,001 - 8,000 17 - 32 Very Stiff > 8,001 32+ Hard RELATIVE DENSITY OF COARSE -GRAINED SOILS Standard Penetration (SPT) or N Value (SS) Blows/Ft Relative Density 0-3 Very Loose 4-9 Loose 10 - 29 Medium Dense 30 - 49 Dense 50+ Very Dense SPT penetration test using 140 pound hammer, with 30 inch free fall on 2 inch outside diameter(I -3/8 ID) sampler For ring sampler using 140 lb hammer, with a 30 inch free fall on 3 inch outside diameter (2-1/2 ID) sample, use N-value x 0.7 to get Standard N-value For fine grained soil consistency, thumb penetration used per ASTM D-2488 RELATIVE PROPORTIONS OF SAND & GRAVEL Descriptive Term of other constituents Percent of Dry Weight Trace < 15 With 15 - 29 Modifier > 30 GRAIN SIZE TERMINOLOGY Major Component of Sample Particle Size Boulders Over 12 inches Cobbles 3 inches to 12 inches Gravel #4 Sieve to 3 inches Sand #200 Sieve to #4 Sieve Silt or Clay Passing #200 Sieve RELATIVE HARDNESS OF CEMENTED SOILS (CALICHE) Description General Characteristics Very Dense to Moderately Hard Partially Cemented Granular Soil - Can be carved with a knife and broken with force by hand. Very Stiff to Moderately Hard Partially Cemented Fine -Grained Soil - Can be carved with a knife and broken with force by hand. Moderately Hard Moderate hammer blow required to break a sample Hard Heavy hammer blow required to break a sample Very Hard Repeated heavy hammer blow required to break a sample LOG LEGEND MATERIAL DESCRIPTION Soil Pattern USCS Symbol USCS Classification FILL GP or GW Artificial Fill Poorly/Well graded GRAVEL GM Silty GRAVEL ���Z GC Clayey GRAVEL GP -GM or GW-GM Poorly/Well graded GRAVEL with Silt GP -GC or GW-GC Poorly/Well graded GRAVEL with Clay SP or SW Poorly/Well graded SAND SM Silty SAND SC Clayey SAND SP-SM or SW-SM Poorly/Well graded SAND with Silt SP-SC or SW -SC Poorly/Well graded SAND with Clay SC-SM Silty Clayey SAND ML SILT IIIIIIIIIIIIIIIIIIII MH Elastic SILT CL-ML Silty CLAY CL Lean CLAY CH Fat CLAY PCEM CEM BDR PARTIALLY CEMENTED CEMENTED BEDROCK SAMPLING SPT Ring Sample No Recovery Bulk Sample Water Table E CONSISTENCY Cohesionless Soils Cohesive Soils Cementation VL Very Loose So Soft MH Moderately Hard L Loose F Firm H Hard MD Medium Dense S Stiff VH Very Hard D Dense VS Very Stiff VD Very Dense TEST PIT LOG LOGGED BY: SJH As:�� PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24121 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES 0 v a .. L � TEST PIT NUMBER: TP-1 N REMARKS FA G E J, o m 0 U)i D V MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk. Brown, SILT,Moist So Organics/roots upper 1 ML Brown to Dk. Brown, SILT, Moist F 2 ML Lt. Brown to Brown, Sandy SILT, Slightly Moist to Moist F 3 4 PCEM Tan to Lt. Brown, PARTIALLY CEMENTED Silty SAND, Slightly Moist MH 5 SM Lt. Brown, Silty SAND, Moist MD 6 7 8 SP Tan to Lt. Brown, Poorly graded SAND, Moist to Saturated MD 9 Ground water seepage noted @ 10.0' 10 11 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Saturated D "Pit Run" 12 END OF TEST PIT @ 12.0- 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: S,H PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES C .-. s b TEST PIT NUMBER: TP-2 2 REMARKS 01 E o o. o U) G �n m H 7 U MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk Brown, SILT, Moist So Organics roots upper I. ML Brown to Dk. Brown, SILT, Moist F 2 SM Lt. Brown, Silty SAND, Moist MD Weak cementation throughout 3 4 5 GP Tan to Lt Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist to Saturated D "Pit Run" 6 Percolation testing conducted @ 5.5' 7 8 9 10 Groundwater measured @ 10.0' Piezometer installed @ I I.0' 11 END OF TEST PIT @ I I.0' 12 13 14 15 16 17 IS 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: G E O T E K SAMPLES 0 v p, .. s i tn TEST PIT NUMBER: TP-3 REMARKS a G �, E N o _ to M C v► m N (n 3 �j MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk. Brown, SILT, Moist So Organics/roots upper 1.01 MIL Brown to Dk. Brown, SILT, Moist F 2 ML Lt. Brown to Brown, Sandy SILT, Moist F Weak cementation throughout 3 4 SM Lt. Brown, Silty SAND, Moist MD 5 6 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist MD "Pit Run" 7 8 END OF TEST PIT @ 8.0- Test pit caving in 9 NO GROUNDWATER ENCOUNTERED 10 II 12 13 14 15 I6 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES t TEST PIT NUMBER: TP-4 REMARKS � N o N j C to m vVi 7 � MATERIAL DESCRIPTION AND COMMENTS FILL town to town, SILT,Moist So rganics roots upper1.01 ML Brown to Dk. Brown, SILT, Moist F 2 ML Lt. Brown to Brown, Sandy SILT, Moist F Weak cementation throughout 3 Percolation testing conducted @ 4.0' 4 GP Tan to Lt Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist to Saturated D "Pit Run" 5 6 7 8 Ground water measured @ 8.7' Piezometer installed @ 9.0' 9 END OF TEST PIT @ 9.0' Test pit caving in 10 II 12 13 14 15 I6 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES u �_ r i a° TEST PIT NUMBER: TP-5 4j IVIL 4 REMARKS y G a E o _ 0 H #A c U MATERIAL DESCRIPTION AND COMMENTS 1A m FILL Brown to Dk. rown, SILT, Moist So Organics/roots upper ML Brown to Dk. Brown, SILT, Moist F 2 SM Lt. Brown to Brown, Silty SAND, Moist MD Weak cementation throughout 3 —x 4 5 6 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist D 'Pit Run' 7 8 END OF TEST PIT @ 8.0' Test pit caving in 9 NO GROUNDWATER ENCOUNTERED 10 II 12 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: SJH AE:�� PROJECT M 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES a � s i TEST PIT NUMBER: TP-6 u 2 a N d �n .N REMARKS C C o � V) vVi V MATERIAL DESCRIPTION AND COMMENTS m m FILL Brown to Dk. grown, SILT,Moist So Organics/roots upper Iff ML Brown to Dk. Brown, SILT, Moist F 2 SM Lt. Brown to Brown, Silty SAND, Moist MD Weak cementation throughout 3 4 Percolation testing conducted @ 4.0' 5 6 GP Lt. Brown to Reddish Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist to Saturated D "Pit Run" 7 8 9 10 Groundwater measured @ 10.0' Piezometer installed @ 10.5' 11 END OF TEST PIT @ 10.5- 12 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES C C a i. s L E TEST PIT NUMBER: TP-7 V d REMARKS c G N 0 O # C G V MATERIAL DESCRIPTION AND COMMENTS vi m m D l FILL Brown to Dk. Brown, SILT, Moist So Organics/roots upper ML Brown to Dk. Brown, SILT, Moist F 2 SM Lt. Brown to Brown, Silty SAND, Moist MD 3 4 5 6 SP Tan to Lt. Brown, Poorly graded SAND, Moist MD 7 END OF TEST PIT @ 7.0- Test pit caving in 8 NO GROUNDWATER ENCOUNTERED 9 10 II 12 13 14 l5 l6 17 18 19 20 TEST PIT LOG LOGGED BY: S,H Apx--4� PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24121 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES C it �_ ^ TEST PIT NUMBER: TP-8 REMARKS a o, d in c G E FA o m o H uVi 7 lJ MATERIAL DESCRIPTION AND COMMENTS FILL Brown to rown, SILT,Moist So Organics/roots upper Iff 1 ML Brown to Dk. Brown, SILT, Moist F 2 ML Lt. Brown to Brown, Sandy SILT, Moist F Weak cementation throughout 3 PCEM Tan to Lt. Brown, PARTIALLY CEMENTED Silty SAND, Slightly Moist MH 4 SM Lt. Brown to Brown, Silty SAND, Moist MD Percolation testing conducted @ 4.5' 5 6 7 8 9 10 GP Lt. Brown to Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist to Saturated D "Pit Run" 11 Groundwater measured @ 11.5' Piezometer installed @ 12.0' 12 END OF TEST PIT @ 12.0' 13 14 15 I6 17 18 19 20 TEST PIT LOG LOGGED BY: S,H AE:�� PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: G E 4 T E K SAMPLES CL L C TEST PIT NUMBER: TP-9 Y y REMARKS 2 G v► o m3 FA vUi U iMATERIAL DESCRIPTION AND COMMENTS FILL rown to k. rown, IL Moist So Organics/roots upper I. ' ML Brown to Dk. Brown, SILT, Moist F 2 ML Lt. Brown to Brown, Sandy SILT, Moist F 3 4 PCEM Tan to Lt. Brown, PARTIALLY CEMENTED Silty SAND, Slightly Moist MH 5 6 SM Lt. Brown, Silty SAND, Moist MD 7 8 9 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist D "Pit Run" 10 END OF TEST PIT @ 10.0- 1 1 NO GROUNDWATER ENCOUNTERED 12 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: S,H PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: G E O T E K SAMPLES C CL P �_ ^ s � TEST PIT NUMBER: TP-10 d REMARKS a E o d p H ai c C rn m 7 U MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk. Brown, SILT, Moist So Organics/roots upper I. ML Brown to Dk Brown, SILT, Moist F 2 ML Lt. Brown to Reddish Brown, Sandy SILT, Moist F 3 4 5 PCEM Tan to Reddish Brown, PARTIALLY CEMENTED Silty SAND, Slightly Moist MH 6 SM Lt. Brown to Brown, Silty SAND, Moist MD Percolation testing conducted @ 7.0' GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist to Saturated D "Pit Run" 8 9 10 Ground water measured @ ION Piezometer installed @ I I.0' 11 END OF TEST PIT @ I I.0' 12 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24121 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES a v E TEST PIT NUMBER: TP-I I c H REMARKS a H L c G �n o0 m � 7 U MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk. Brown, SILT, Moist So Organics/roots upper I. ML Brown to Dk. Brown, SILT, Moist F 2 SM Lt. Brown, Silty SAND, Moist MD Weak cementation throughout 3 4 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist D "Pit Run" 5 6 7 8 END OF TEST PIT @ 8.0- Test pit caving in' 9 NO GROUNDWATER ENCOUNTERED 10 II 12 13 14 15 I6 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT M 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3124121 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES C 0 �. r. y N TEST PIT NUMBER: TP-12 0 REMARKS C o 12 b to m N FA D � j MATERIAL DESCRIPTION AND COMMENTS FILL grown to Dk. Brown, SILT,Moist So Organics/roots upper 1 ML Brown to Reddish Brown, Sandy SILT, Moist F 2 Percolation testing conducted @ 2.0' 3 SM Lt. Brown, Silty SAND, Moist MD 4 PCEM Lt. Brown to Brown, PARTIALLY CEMENTED Silty SAND, Slightly Moist MH 5 6 SM Brown, Silty SAND, Moist to Saturated MD 8 9 Ground water measured @ 9.0' 10 I I Piezometer installed @ 1 1.0' END OF TEST PIT @ 1 1.0- 12 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: S)H PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24121 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES I- s GLl E N TEST PIT NUMBER: TP-13 C N REMARKS 1 d 01 N C �n o m3 N VVi V FMATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk. Brown, SILT, Moist So Organics1roots upper . MIL Brown to Dk. Brown, SILT, Moist F 2 SM Lt. Brown, Silty SAND, Moist MD 3 4 5 6 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist D "Pit Run" 7 8 END OF TEST PIT @ 8.0- Test pit caving in 9 NO GROUNDWATER ENCOUNTERED 10 11 12 13 14 IS I6 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES C r ^ TEST PIT NUMBER: TP-14 REMARKS C o IL CA N C (A m 4A H U MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk Brown, SILT, Moist So Organics/roots upper 1. ML Brown to Dk. Brown, SILT, Moist F 2 ML Brown, Sandy SILT, Moist F 3 Percolation testing conducted @ 3.5' 4 5 6 SM Lt. Brown to Brown, Silty SAND, Moist MD 7 8 9 10 II GP Lt Brown to Reddish Brown, Poorly graded GRAVEL with Sand and Cobbles. Moist to Saturated D "Pit Run" 12 Ground water measured @ 12.8' 13 Piezometer installed @ 14.0' 14 END OF TEST PIT @ 14.0' 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: S,H AP PROJECT #: 2240-ID METHOD: Backhoe xaw� PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES V s .0 TEST PIT NUMBER: TP-I S REMARKS a N o ILN 0 X GE In m uVi j MATERIAL DESCRIPTION AND COMMENTS 1 FILL Brown to Dk. Brown, SILT, Moist So Organics/roots upper I. ML Brown to Dk. Brown, SILT, Moist F 2 ML Lt. Brown to Brown, Sandy SILT, Moist F 3 4 SM Tan to Lt. Brown, Silty SAND, Moist MD 5 PCEM Lt. Brown, PARTIALLY CEMENTED Silty SAND, Slightly Moist MH 6 SP Tan to Lt. Brown, Poorly graded SAND, Moist MD 8 9 GP Tan to Lt. Brown, Poorly graded GRAVEL with Sand and Cobbles, Moist D 'Pit Run" 10 END OF TEST PIT @ 10.0- 1 1 NO GROUNDWATER ENCOUNTERED 12 13 14 15 16 17 18 19 20 TEST PIT LOG LOGGED BY: SJH PROJECT #: 2240-ID METHOD: Backhoe PROJECT: Sky Pilot Subdivision EXCAVATOR: Just Dig It CLIENT: Lasher Enterprises DATE: 3/24/21 G E O T E K LOCATION: West of N McDermott Rd & W Becky Dr ELEVATION: SAMPLES C O a ^ $ � TEST PIT NUMBER: TP-IG REMARKS CL o � GE U) m 0 VVi U MATERIAL DESCRIPTION AND COMMENTS FILL Brown to Dk Brown, SILT, Moist So Organics/roots upper I . SM Lt. Brown to Brown, Silty SAND, Moist MD 2 3 4 5 SP Tan to Lt. Brown, Poorly graded SAND, Moist MD 6 7 END OF TEST PIT @ 7.0- Test pit caving in 8 NO GROUNDWATER ENCOUNTERED 9 10 II 12 13 14 15 16 17 18 19 20 APPENDIX C GeoTek, Inc. FIELD TESTS AND OBSERVATIONS (2240-ID) PERCOLATION TESTS The infiltration rate was determined by conducting percolation tests for onsite earth materials. The infiltration rate was determined in inches per hour in general accordance with the City of Meridian requirements. Infiltration rate results are presented below. The infiltration rates provided below should be used for design and not exceeded. LOCATION USCS Soil Classification Symbol INFILTRATION RATE (Inches/Hour) TP-2 @ 5.5' GP 7.5 TPA @ 4.0' GP 7.2 TP-6 @ 4.0' SM 3.5 TP-8 @ 4.5' SM 3.2 TP-10 @ 7.0' GP 7.6 TP-12 @ 2.0' ML 1.5 TP-14 @ 3.5' ML 1.1 GROUND WATER MONITORING RESULTS Ground water monitoring results are presented below. Ground water elevation results are recorded in feet below existing grade. STAND -PIPE TP-2 TP-4 TP-6 TP-8 TP-10 TP-12 TP-14 PIEZOMETER # 3-30-21 10.0 8.7 10.0 11.5 10.6 9.0 12.8 "+" Indicates a dry reading at the bottom of the piezometer "n/a" Indicates that the piezometer was damaged/missing in the field and no measurements were obtained. GeoTek, Inc. APPENDIX D GeoTek, Inc. LABORATORY TESTS RESULTS (2240-ID) ATTERBERG LIMITS Atterberg limits were performed on representative samples in general accordance with ASTM D 4318. The results are shown in the following plates. PARTICLE SIZE ANALYSIS Sieve analyses were performed in general accordance with ASTM test method C 136 and ASTM C 1 17. Test results are presented in the following plates. RESISTANCE R-VALUE AND EXPANSION PRESSURE OF COMPACTED SOILS Tests were conducted on representative soil samples, in general accordance with Idaho test method T-8 and AASHTO T-190, to determine the soil's performance when placed in the base, subbase, or subgrade of a road subjected to traffic. LOCATION R-VALUE @ 200 psi TP-2 @ 0.5'- IS 8 GeoTek, Inc. GeoTek - Idaho 320 Corporate Drive, Ste #300 7950 Meadowlark Way, Ste E Meridian, ID 83642 Coeur d'Alene, ID 83815 Phone: (208) 888-7010 (208) 888-7924 Fax: (208)904-2980 (208)904-2981 Material Test Report Client: Lasher Enterprises CC: 3327 N Eagle Road Meridian ID 83642 Project: 2240-I D Sky Pilot Subdivision Sample Details Sample ID Date Sampled Specification Location Particle Size Distribution 21-00241-S01 3/24/2021 General Sieve Set TP-1, 0.5'-1.5' Z Z Z Z Z o Z Z Sieve Report No: MAT:21-00241-S01 II THIS DOCUMENT SHALL NOT BE REPRODUCED EXCEPT IN FULL COBBLES GRAVEL SAND FINES (87.3%) Coarse Fine Coarse Medium Fine Silt Clay (0.0%) (0.0%) (0.0%) (0.2%) (2.6%) (10.0%) Sample Description: ML, SILT Atterberg Limit: - Liquid Limit: 34 Plastic Limit: 25 Plasticity Index: 9 Grading: ASTM C 136, ASTM C 11� Date Tested: Tested By: Sieve Size % Passing Limits No.4 100 No.8 100 No.16 99 No.30 98 No.50 96 No.100 93 No.200 87 D85: N/A D60: N/A D50: N/A D30: N/A D15: N/A D10: N/A Form No: 18909, Report No: MAT:21-00241-S01 © 2000-2021 QESTLab by SpectraQEST.com Page 1 of 2 GeoTek - Idaho 320 Corporate Drive, Ste #300 7950 Meadowlark Way, Ste E Meridian, ID 83642 Coeur d'Alene, ID 83815 Phone: (208) 888-7010 (208) 888-7924 Fax: (208) 904-2980 (208) 904-2981 Material Test Report Client: Lasher Enterprises CC: 3327 N Eagle Road Meridian ID 83642 Project: 2240-I D Sky Pilot Subdivision Sample Details Sample ID Date Sampled Specification Location Particle Size Distribution 21-00241-S03 3/24/2021 General Sieve Set TP-5, 2.0'-3.0' Report No: MAT:21-00241-S03 II THIS DOCUMENT SHALL NOT BE REPRODUCED EXCEPT IN FULL COBBLES GRAVEL SAND FINES (33.8%) Coarse Fine Coarse Medium Fine Silt Clay (0.0%) (0.0%) (7.8%) (12.4%) (23.2%) (22.8%) Sample Description: SM, Silty SAND Atterberg Limit: - Liquid Limit: N/A Plastic Limit: NP Plasticity Index: NP Grading: ASTM C 136, ASTM C 117 - Date Tested: Tested By: Sieve Size % Passing Limits '/zi n 100 3/8in 98 No.4 92 No.8 82 No.16 72 No.30 61 No.50 52 No.100 43 No.200 34 D85: 2.9110 D60: 0.5555 D50: 0.2572 D30: N/A D15: N/A D10: N/A Form No: 18909, Report No: MAT:21-00241-S03 © 2000-2021 QESTLab by SpectraQEST.com Page 1 of 2 GeoTek - Idaho 320 Corporate Drive, Ste #300 7950 Meadowlark Way, Ste E Meridian, ID 83642 Coeur d'Alene, ID 83815 Phone: (208) 888-7010 (208) 888-7924 Fax: (208) 904-2980 (208) 904-2981 Material Test Report Client: Lasher Enterprises CC: 3327 N Eagle Road Meridian ID 83642 Project: 2240-I D Sky Pilot Subdivision Sample Details Sample ID Date Sampled Specification Location Particle Size Distribution 21-00241-SO4 3/24/2021 General Sieve Set TP-8, 8.0'-9.0' Report No: MAT:21-00241-SO4 II THIS DOCUMENT SHALL NOT BE REPRODUCED EXCEPT IN FULL COBBLES GRAVEL SAND FINES (47.5%) Coarse Fine Coarse Medium Fine Silt Clay (0.0%) (0.0%) (1.9%) (3.8%) (17.3%) (29.5%) Sample Description: SM, Silty SAND Atterberg Limit: - Liquid Limit: N/A Plastic Limit: NP Plasticity Index: NP Grading: ASTM C 136, ASTM C 11� Date Tested: Tested By: Sieve Size % Passing Limits 3/8i n 100 No.4 98 No.8 95 No.16 91 No.30 82 No.50 72 No.100 60 No.200 47 D85: 0.7517 D60: 0.1500 D50: 0.0880 D30: N/A D15: N/A D10: N/A Form No: 18909, Report No: MAT:21-00241-SO4 © 2000-2021 QESTLab by SpectraQEST.com Page 1 of 2 GeoTek - Idaho 320 Corporate Drive, Ste #300 7950 Meadowlark Way, Ste E Meridian, ID 83642 Coeur d'Alene, ID 83815 Phone: (208) 888-7010 (208) 888-7924 Fax: (208) 904-2980 (208) 904-2981 Material Test Report Client: Lasher Enterprises CC: 3327 N Eagle Road Meridian ID 83642 Project: 2240-I D Sky Pilot Subdivision Sample Details Sample ID Date Sampled Specification Location Particle Size Distribution 21-00241-S05 3/24/2021 General Sieve Set TP-15, 4.0'-5.0' Report No: MAT:21-00241-S05 II THIS DOCUMENT SHALL NOT BE REPRODUCED EXCEPT IN FULL COBBLES GRAVEL SAND FINES (35.8%) Coarse Fine Coarse Medium Fine Silt Clay (0.0%) (0.0%) (13.3%) (9.7%) (19.7%) (21.5%) Sample Description: SM, Silty SAND Atterberg Limit: - Liquid Limit: N/A Plastic Limit: NP Plasticity Index: NP Grading: ASTM C 136, ASTM C 117 - Date Tested: Tested By: Sieve Size % Passing Limits 3/4i n 100 'hi n 95 3/8in 93 No.4 87 No.8 79 No.16 70 No.30 61 No.50 53 No.100 45 No.200 36 D85: 3.9879 D60: 0.5502 D50: 0.2313 D30: N/A D15: N/A D10: N/A Form No: 18909, Report No: MAT:21-00241-S05 © 2000-2021 QESTLab by SpectraQEST.com Page 1 of 2 APPROXIMATE TEST PIT LOCATIONS Source: Google Earth 2018, GeoTek Field Observations, 2021. Not to Scale GEOTEK GEOTECHNICAL I ENVIRONMENTAL I MATERIALS 320 E. Corporate Dr, Suite 300, Meridian, ID 83642 (208) 888-7010 (phone) / (208) 888-7924 (FAX) I FIGURE 2 SITE EXPLORATION PLAN Aviator Springs (Sky Pilot) Subdivision West of N McDermott Rd & W Becky Dr Meridian, Idaho Prepared for: Lasher Enterprises Project No.: Report Date: Drawn By: 2240-ID January 2022 SJH i y 2240-ID Aviator Springs (Sky Pilot Sub) Trip No. Date TP-2 TP-4 TP-6 TP-8 TP-10 TP-12 TP-14 Notes 0 3/30/21 10.0' 8.7' 10.0' 11.5' 10.6' 9.0' 12.8' 1 4/21 /21 10.3' 8.9' 10.2' HE 10.8' 9.2' 13.1' 2 5/7/21 10.3' 9.0' 10A 11.8' 10.8' 9.4' 13.1' 3 5/20/21 6.0' 5.9' 7.2' 9.3' 8.3' 7.3' 1 1.6' Irrigation on entire field 4 6/3/21 4.8' 6.1' 4.6' 8.0' 6.5' 7.5' 10.4' Irrigation noted 5 6/ 18/21 5.8' 6.4' 6.9' 8.6' 7.2' 7.2' 1 1.3' 6 7/ I /21 6.7' 6.9' 7.7' 9.0' 8A 8.2' 10.3' Water in adjacent canal 7 7/ 15/21 5.9' 7.2' 7.7' 8.9' 8.3' 7.7' 10.6' 8 7/29/21 5.3' 8.0' 7.0' 7.8' 7.7' 7.6' 11.1' 9 8/1 2/2 1 4.5' 5.9' 6.5' 7.5' 6.9' 7.2' 9.3' 10 8/26/21 4A 5.4' N/A 7.3' 6A 5.9' 8.9' TP-6 taken out by farming 11 9/9/21 5.2' 5.7' 6.5' 7.8' 6.1' 5.8' 9.2' Tech fixed TP-6 12 9/23/21 5.0' 6.1' 6.7' 7.5' 6.3' 6.4' 9.2' 13 10/7/21 5.8' 6.8' N/A 8.3' 7.1' 7.0' 10.0' TP-6 broken again 14 10/22/21 10.3' 7.9' N/A 9.1' 10.6' 7.7' 11.1' 5 1 1 /22/21 6.9' 6.9' N/A 10.1' 7.9' 8.0' 1 1.8' 16 12/22/21 N/A 8.0' N/A 10.8' 10.4' 9.0' 12.5' 17 1 /21 /22 6.9' 7.8' N/A 10.6' 10.1' 9.0' 12.0' I8 KEY Indicates dry reading at bottom of Diezometer "N/A" Indicates that piezometer is damaged or missing - therefore no data was obtained Note: Groundwater elevation results are recorded in feet below approximate existing grade. Generally, irrigation ditches and canals will locally influence ground water during the irrigation season.