Loading...
CC - Drainage ReportKimley»>Horn Oakwind Estates Subdivision Meridian, ID Prepared By: Kimley-Horn Associates 950 W Bannock St Suite 1100 Boise, ID 83702 Contact: Brandon McDougald, P.E. (801) 915-7842 16551 01 /10/2 v 9 00 Job No. 093893000 January 10, 2021 Kimley>»Horn GENERAL LOCATION AND DESCRIPTION This drainage study is being prepared for both Phase 1 and Phase 2 of the Oakwind Estates Subdivision in Meridian, Idaho. The site is located to the northeast of the intersection of McDermott Road and McMillan Road. It is bound to the north by a commercial development, east by Phases 1 and 2 of the Oaks North Subdivision, west by McDermott Road, and south by McMillan Road. This project consists of approximately 24.36 acres and 185 lots. The site is located within section 28, Township 4 North, Range 1 West Meridian, Ada County, Idaho. The proposed development will consist of approximately 212 residential and common lots with the associated roadways and utilities. The site currently slopes mostly to the west at a grade of ±0.25-1%. The site is currently a portion of an undeveloped field used historically for agricultural purposes. The site is in zone "X", an area determined to be outside the 0.2% annual chance floodplain, according to the Flood Insurance Rate Map, Map Number 16001C0140J, which bears an effective date of June 19, 2020. HISTORIC DRAINAGE Currently, the site is undeveloped, and is bounded by McDermott Rd to the west and McMillan to the south. This site generally slopes from the southeast to the west at a rate of approximately 0.25-1'%. In the existing condition it appears that storm water runoff will mostly infiltrate into the undeveloped ground. Any uncaptured runoff appears to drain to ditches along McMillan or McDermott where it is eventually conveyed by a culvert under McDermott to the west. No detention/retention was found to be existing on the current site. III. DRAINAGE DESIGN CRITERIA Ada County Highway District (ACHD) requires that new developments provide primary conveyance for the 100-yr storm event and retention for the 100-yr storm event. The site has been designed to these standards with detention volumes being determined for the 1-hr 100-yr event per the ACHD Calculation Sheet for Finding Peak Discharge/Volume Spreadsheet. This volume was used to design the infiltration beds. The infiltration rate and high groundwater elevation for this design were taken from a geotechnical report prepared by Materials Testing and Inspection, Inc. dated July 20, 2018 and numbered 13180977g. The Rational Method was used in calculating the required retention volume for the site. The site was delineated into drainage areas based upon the proposed grading and drainage design. The C-factor was taken to be 0.5 which is the higher end for single family residential listed in the ACHD "Estimated Runoff Coefficients for Various Surfaces" table. Along the McDermott Kimley>»Horn frontage where the residential C-factor did not apply, a composite C-factor was determined using 0.9 for the roadway and 0.35 for the planted areas. The required volume and the provided volume of retention for each drainage area has been calculated and is shown in the appendixes along with all design assumptions. III. PROPOSED DRAINAGE The proposed drainage infrastructure will consist of an on -site storm drain system discharging into an underground infiltration bed for each of the drainage areas. Prior to releasing water into the on -site underground infiltration beds, the water will be treated by a sand/oil separator unit per ISPWC SD-606. This treatment unit will be capable of treating the 25-year event. Since the seepage beds are located in common lots no silt factor was used in sizing the infiltration beds per the requirements of the ACHD design requirements. The design infiltration rate was taken to be 8.Oin/hr per the geotechnical report No. B180977g prepared by Materials Testing & Inspection, Inc. Given this infiltration rate each infiltration bed will drain in under the required 48 hrs. Kimley>»Horn 1v�e1»a►111Kl Seepage Bed - 01 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 0.50 2.92 acres 0.00 cfs V 5,046 3 Link to: Q•v QV TR55 5,046 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 38.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 71.1 71.1 ft'/ft 15 Calculate Design Length L 71 71 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 71 71.0 ft 17 Variable Infiltration Window W SWW 38.0 38.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 71 79 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9r Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft, 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90% volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_3.xlsm 111012022, 3:36 PM Version 10.0, May 2018 Seepage Bed - 02 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.50 5.99 acres 0.00 cfs V 10,351 3 Link to: Q•v QV TR55 10,351 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 54.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 101.0 101.0 ft,/ft 15 Calculate Design Length L 102 102 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 102 74.0 ft 17 Variable Infiltration Window W SWW 54.0 30.0 ft 18 Time to Drain 6.3 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 102 185 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_6.xlsm 1/10/2022, 3:40 PM Version 10.0, May 2018 Seepage Bed - 03 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.50 1.93 acres 0.00 cfs V 3,335 Link to: Q•v QV TR55 3,335 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 17.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 31.9 31.9 ft'/ft 15 Calculate Design Length L 0 105 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 105 100.0 ft 17 Variable Infiltration Window W SWW 17.0 17.0 ft 18 Time to Drain 2.6 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 105 100 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_1.xlsm 1/10/2022, 3:32 PM Version 10.0, May 2018 Seepage Bed - 04 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.50 2.19 acres 0.00 cfs V 3,784 3 Link to: Q•v QV TR55 3,784 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 23.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 43.1 43.1 ft'/ft 15 Calculate Design Length L 0 88 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 88 92.0 ft 17 Variable Infiltration Window W SWW 23.0 22.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 88 92 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_2.xlsm 1/10/2022, 3:35 PM Version 10.0, May 2018 Seepage Bed - 05 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 0.50 0.93 acres 0.00 cfs V 1,607 3 Linkto: Q•v QV TR55 1,607 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 10.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 18.8 18.8 ft'/ft 15 Calculate Design Length L 85 86 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 86 ft 17 Variable Infiltration Window W SWW 10.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 86 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Bpi onai acorage Lnamoers Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft, 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90% volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_5.xlsm 111012022, 3:39 PM Version 10.0, May 2018 Seepage Bed - 06 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.50 1.51 acres 0.00 cfs V 2,609 3 Link to: Q•v QV TR55 2,609 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 20.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 37.5 37.5 ft'/ft 15 Calculate Design Length L 70 70 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 70 70.0 ft 17 Variable Infiltration Window W SWW 20.0 20.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 70 70 ft 20 Perf Pipe Checks. Qperf>= Qpeak; O where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9r MW Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft, 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90% volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_4.xlsm 111012022, 3:38 PM Version 10.0, May 2018 Seepage Bed - 07 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.65 0.63 acres 0.00 cfs V 1,415 3 Link to: Q•v QV TR55 1,415 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 10.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 18.8 18.8 ft'/ft 15 Calculate Design Length L 0 76 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 76 76.0 ft 17 Variable Infiltration Window W SWW 10.0 10.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 76 76 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_10.xlsm 1/10/2022, 3:45 PM Version 10.0, May 2018 Seepage Bed - 08 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.65 0.26 acres 0.00 cfs V 584 3 Link to: Q•v QV TR55 584 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 10.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 18.8 18.8 ft'/ft 15 Calculate Design Length L 31 32 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 32 32.0 ft 17 Variable Infiltration Window W SWW 10.0 10.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 32 32 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_11.xlsm 1/10/2022, 3:46 PM Version 10.0, May 2018 Seepage Bed - 09 Phase 1 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.65 0.84 acres 0.00 cfs V 1,887 3 Link to: Q•v QV TR55 1,887 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 10.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 18.8 18.8 ft'/ft 15 Calculate Design Length L 100 101 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 101 101.0 ft 17 Variable Infiltration Window W SWW 10.0 10.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 101 101 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_12.xlsm 1/10/2022, 3:48 PM Version 10.0, May 2018 Seepage Bed - 10 Phase 2 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.50 2.02 acres 0.00 cfs V 3,491 3 Link to: Q•v QV TR55 3,491 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 31.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 58.0 58.0 ft'/ft 15 Calculate Design Length L 0 61 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 61 80.0 ft 17 Variable Infiltration Window W SWW 31.0 15.0 ft 18 Time to Drain 3.9 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 61 80 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9W Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft3 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90%volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_7.xlsm 1/10/2022, 3:41 PM Version 10.0, May 2018 Seepage Bed - 11 Phase 2 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 0.50 1.75 acres 0.00 cfs V 3,024 Link to: Q•v QV TR55 3,024 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 15.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 28.2 28.2 ft'/ft 15 Calculate Design Length L 0 107 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 107 ft 17 Variable Infiltration Window W SWW 15.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 107 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Bpi onai acorage Lnamoers Note: This assumes chambers are organized in a rectangular layout. 1 Type of Chambers 2 Volume to Store V 3 Installed Chamber Width Cw Installed Chamber Depth Cd Installed Chamber Height Ch 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 6 Chamber Storage Volume, With Rock, Per Manuf 7 Total Number of Units Required 8 Area of Infiltration Aperc 9 Volume Infiltration Vperc 10 Time to Drain 90% volume in 48-hours minimum ft2 0 ft3/hr hours .3 K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_8.xlsm 111012022, 3:43 PM Version 10.0, May 2018 Seepage Bed - 12 Phase 2 ACHD Calculation Sheet for Sizing Seepage Bed With Optional Chambers 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. Note this spreadsheet pulls information from the "Peak QV" tab 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 Oakwind Estates 2 Enter number of Seepage Beds (25 max) 3 Design Storm 4 Weighted Runoff Coefficient C 5 Area A (Acres) 6 Approved discharge rate (if applicable) 7 Is Seepage Bed in Common Lot? Yes 100 0.50 2.69 acres 0.00 cfs V 4,648 3 Link to: Q•v QV TR55 4,648 ft' 0%Sediment 8 Set Total Design Width of All Drain Rock W 27.0 ft 9 Set Total Design Depth of All Drain Rock D 3.0 ft Rock Only, Do Not Include Filter Sand Depth or Cover 10 Void Ratio of Drain Rock Voids 0.4 0.4 for 1.5"-2" drain rock and 3/4" Chips 11 Design Infiltration Rate (8 in/hr max) Perc 8.00 in/hr 12 Size of WQ Perf Pipe (Pert 180°) Dia pipe 18 in 13 Size of Overflow Perf Pipe (Perfs 360°), REQD if Q100>3.3 cfs in 14 Calculate Total Storage per Foot Spf 50.6 50.6 ft'/ft 15 Calculate Design Length L 0 92 ft Override Value Required for Chambers 16 Variable Infiltration Window L SWL 92 92.0 ft 17 Variable Infiltration Window W SWW 27.0 27.0 ft 18 Time to Drain 2.5 hours 90%volume in 48-hours minimum 19 Length of WQ & Overflow Perf Pipes 92 92 ft 20 Perf Pipe Checks. Qperf>= Qpeak; where Qperf=CdxAxV(2xgxH) Optional Storage Chambers 9 Note: This assumes chambers are organized in a rectangular layout. 1-StormTech, 1 Type of Chambers SC740 2 Volume to Store V 0 ft, 3 Installed Chamber Width Cw 4.25 ft Installed Chamber Depth Cd 2.50 ft Installed Chamber Height Ch 7.12 ft 4 Chamber Void Factor 5 Chamber Storage Volume, Without Rock, Per Manuf 45.90 ft3 6 Chamber Storage Volume, With Rock, Per Manuf 74.90 ft3 7 Total Number of Units Required 0 ea 8 Area of Infiltration Aperc ftz 9 Volume Infiltration Vperc 0 ft3/hr 10 Time to Drain hours 90% volume in 48-hours minimum K:\BOI_Civil\093893000 Oakwind BB Living\_Project Files\Eng\Drainage\ACHD Calcs\ACHD_SD_CALCS_9.xlsm 111012022, 3:44 PM Version 10.0, May 2018 APN: APN. SO428325610 SO428325460 — — — — 0 SP-12 � I51SI I I 5 I 4 3 I 2 I 1 I I I I , 15 174 , 11 10 9 16 SP-10 -- —�I —BLOCK 2.s6.9 BLOCK 8 —1 — APN: SO429440000 ---------------- --- --- ---- I I , I , I — — I r— I EXISTING OAKS NORTH SUBDIVISION NO. 2 (NOT A PART) w 0 O z Q J 72 / I \ I I I I I 1 I I I EXISTING OAKS NORTH SUBDIVISION NO. 1 _ (NOT A PART) I I I W o, I , 1944111 C FACTOR o.5 DRAINAGE AREA DESIGNATION 7 DRAINAGE AREA (AC) ### DRAINAGE AREA BOUNDARY 811 Knanrw.r. bebw. Call before yo„ dig. — — — — CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF _ UNDERGROUND — —' M EMBER UTILITIES 6 GRAPHIC SCALE IN FEET 0 30 60 120 NORTH d 0 OAKWIND ESTATES PROPOSED DRAINAGE AREA MAP MERIDIAN, ID a Kim Fey)))Horn z CQ 2022 KIMLEY—HORN AND ASSOCIATES, INC. m 950 Bannock Street, Suite 1100 oo Boise, Idaho 83702 208 297-2885 0 FOR REVIEW ONLY NOT FOR CONSTRUCTION Kimley»)Horn DESIGNED DRAWN C MR BKG SCALE (H): 1"=60' SCALE (V): N/A 1 1 National Flood Hazard Layer FIRMette .. FEMA 116o28'38"W 43o39'13"N -- 1.17,VVV 0 250 500 1,000 1,500 2,000 Basemap: USGS National Map: Orthoimagery. Data refreshed October, 2020 Legend SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT Without Base Flood Elevation (BFE) Zone A, V, A99 SPECIAL FLOOD With BFE or Depth Zone AE, Ao, AH. VE. AR HAZARD AREAS Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mile Zonex Future " Conditions 1% Annual Chance Flood Hazard Zone Area with Reduced Flood Risk due to OTHER AREAS OF Levee. See Notes. Zone FLOOD HAZARD Area with Flood Risk due to Levee zone D NO SCREEN Area of Minimal Flood Hazard Zone Q Effective LOMRs OTHER AREAS Area of Undetermined Flood Hazard Zone D GENERAL - — - - Channel, Culvert, or Storm Sewer STRUCTURES I I I I I I I Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17•5 Water Surface Elevation a - - - Coastal Transact —5f5— Base Flood Elevation Line (BFE) Limit of Study Jurisdiction Boundary — --- Coastal Transact Baseline OTHER _ Profile Baseline FEATURES Hydrographic Feature Digital Data Available N No Digital Data Available MAP PANELS Unmapped QThe pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 1/11/2022 at 10:34 AM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes.