Application MaterialsHearing Date: August 15, 2017
File No.: H-2017-0101
Project Name: Geddes Subdivision
Request: Request for final plat consisting of 10 building lots and 4 common lots on 2.08 acres of
land in the R-8 zoning district, by Schultz Development.
Location: The site is located southeast of the W. Ustick Road and N. Black Cat Road intersection,
in the NW ¼ of Section 3, Township 3N., Range 1W.
(:�ENDIAN;:---
IFCFIVI
JUL 1 1 2017
dX:
STAFF USE ONLY:
Project name:
File number(s): 0101
Assigned Planner: Related files:
Type of Review Requested (check all that apply)
Planning Division
REVIEW APPLICATION
❑ Accessory Use
❑ Planned Unit Development
❑ Administrative Design Review
❑ Preliminary Plat
❑ Alternative Compliance
❑ Private Street
❑ Annexation and Zoning
❑ Property Boundary Adjustment
❑ Certificate of Zoning Compliance
❑ Rezone
❑ City Council Review
❑ Short Plat
❑ Comprehensive Plan Map Amendment
❑ Time Extension:
❑ Comprehensive Plan Text Amendment
Director/ Commission/Council (circle one)
❑ Conditional Use Permit
❑ UDC Text Amendment
❑ Conditional Use Modification
❑ Vacation:
Director/Commission (circle one)
Director/ Council (circle one)
❑ Development Agreement Modification
❑ Variance
Final Plat
❑ Other
❑ Final Plat Modification
Information
Applicant name: ��1�1� "�-` �/ -� l�D U�� Phone: 56c-)`— L 5
Applicant address: P O �6� ` i i 5 Email: C-- ��w-
City: f I G.y�- State:=j '�V'�
(ll �� Zip:
Applicant's inter n property: ❑ Own ❑ Rent ❑ Optioned n8ther
Owner name: `9-e—C4--� q � 1. ^_P Phone: 1 ' 3667
V - C'V 1 —,. Email:
Owner address: '�i`a�,� .�
City: e b ck�tcL^ State: Zip:
Agent/Contact name (e.g., archiect, e.
(; c\r -
Firm name:
developer, representative):
Phone:
Agent address:PU `��— �� Email:
City: �a-q-LCLLC, — 1 State: _�_ Zip:
Primary contact is: KApplicant ❑ Owner (Agent/Contact
Subject Property Information
Location/street
Assessor's parcel number(s)
Township, range, section: 1Lo
!>-2
Total acreage: 2 c 06 Zoning district:
Community Development ■ Planning Division ■ 33 E. Broadway Avenue, Ste. 102 Meridian, Idaho 83642
Phone: 208-884-5533 Fax: 208-888-6854 www.meridiancity.org/planniU
M
(Rei,. 0611212014)
Project/subdivision name: Ge -Ale -5 &"ckty l s t v.
General description of proposed project/request: c-6 \c, , J� l
o-„- Z -� �cd-� i r, ,
Proposed zoning district(s): R9F
Acres of each zone proposed: `4' ` C*3
Type of use proposed (check all that apply):
esidential ❑ Office ❑ Commercial ❑ Employment ❑ Industrial ❑ Other 1
Who will own & maintain the pressurized irrigation system in this development? Vv
Which irrigation district does this ((property lie within? U M' t D
Primary irrigation source: V" N�, i V Secondary: �•
Square footage of landscaped areas to be irrigated (if primary or secondary point of connection is City water): 51F
(QI oz�
Residential Project Summary (if applicable)
Number of residential units: b Number of building lots: Ly
Number of common lots: Number of other lots:
Proposed number of dwelling units (for multi -family developments only):
1 bedroom:
2-3 bedrooms:
f1_0L_
4 or more bedrooms:
Minimum square footage of structure (excl. garage): , Maximum building height: 7 5
Minimum property size (s.f): 4, Average property size (s.f): 4, 5–,6
us
Gross density (Per UDC 11-1A-1): �.�1 � Net density (Per UDC 11-1A-1): g,& Q''`�
Acreage of qualified open space
Percentageof qualified open space:
Type and calculations of qualified open space provided in acres (Per UDC 11 -3G -3B): NCL.
Amenities provided with this development (if applicable): 50Q.J–QQ–
Type of dwelling(s) proposed: gle-family Detached ❑ Single-family Attached ❑ Townhouse
❑ Duplex ❑ Multi -family ❑ Vertically Integrated ❑ Other
Non-residential Project Summary (if applicable) — V\4-;L–
Number of building lots:
Gross floor area proposed:
Hours of operation (days and hours):
Total number of parking spaces provided:
Authorization
Print applicant name
Applicant signature:
Common lots: Other lots:
Existing (if applicable):
Building height:
Number of compact spaces provided:
Date: ro , C-7
Community Development ■ Plamiing Division ■ 33 E. Broadway Avenue, Ste. 102 Meridian, Idaho 83642
Phone: 208-884-5533 Fax: 208-888-6854 www.meridiancity.org//planning
-2- (Rev. 06/12/2014)
July 6, 2017
Mayor Tammy DeWeerd and City Council
City of Meridian
33 E. Broadway Street
Meridian, ID 83642
RE: Geddes Subdivision
Final Plat Submittal
H-2017-0041
Dear Honorable Mayor and City Council Members,
On behalf of Schultz Development LLC, this letter is to accompany the Final Plat
submittal for Geddes Subdivision. The Annexation, Rezone, and Preliminary Plat
applications (H-2017-0041) for the 2.08 acre site were approved on June 20, 2017 by the
City Council. The signed Development Agreement is attached.
The submitted final plat consists of 10 building lots and 4 common lots. The final plat
conforms to all of the requirements and conditions of the approved Preliminary Plat.
The submitted final plat, development plans, and landscape plans conform to the UDC
and all applicable engineering, architectural, and surveying practices and local standards.
Sincerely,
Matt Schultz
Schultz Development LLC
Project Manager
Attachments
April 5, 2017
DESCRIPTION FOR
R-8 ZONE
GEDDES SUBDIVISION
A parcel of land located in the NW 1/4 of the NW 1/4 of Section 3, Township 3
North, Range 1 West, B.M., Meridian, Ada County, Idaho being more particularly
described as follows:
Commencing at the NW corner of said Section 3 from which the W1/4 corner of
said Section 3 bears South 00°37'58" West, 2697.53 feet;
Thence along the West boundary line of said Section 3 South 00037'58" West,
443.88 feet;
Thence leaving said West boundary line South 89°23'11" East, 414.76 feet to
the REAL POINT OF BEGINNING;
Thence continuing South 89°23'11" East, 260.26 feet to a point on the
southwesterly boundary line of Klamath Basin Subdivision as filed in Book 96 of Plats
at Pages 11914 and 11915, records of Ada County, Idaho;
Thence along said southwesterly boundary line the following 2 courses and
distances:
Thence South 52°36'15" East, 106.58 feet;
Thence South 60006'23" East, 22.04 feet to the SW corner of Staten Park
Subdivision as filed in Book 86 of Plats at Pages 9713 and 9714, records of Ada
County, Idaho;
Thence along the southwesterly boundary line of said Staten Park Subdivision
the following 3 courses and distances:
Thence South 60007'02" East, 48.03 feet;
Thence South 64000'36" East, 202.17 feet;
Thence South 54°36'16" East, 44.31 feet to an angle point in the exterior
boundary line of The Lake At Cherry Lane No. 9 Subdivision as filed in Book 81 of
Plats at Pages 8885 and 8886, records of Ada County, Idaho;
Thence along the North boundary line of said The Lake At Cherry Lane No. 9
Subdivision and the North boundary line of Ashford Greens Subdivision as filed in
Book 73 of Plats at Pages 7567 through 7568, records of Ada County, Idaho North
89°23'11" West, 625.89 feet;
Thence leaving said North boundary line North 00038'20" East, 210.00 feet to
the REAL POINT OF BEGINNING. Contains an area of 2.08 acres, more or less. �®
E 10
Ir W
AFTER RECORDING MAIL TO:
Robert C. Campbell
3313 W. Cherry Ln #144
Meridian , ID 83642
File No.: 4102-2664222 (PC)
Date: May 27, 20:6
For Value Received, Michael G. Sorensen and Karen L. Sorensen, husband and wife, hereinafter
referred to as Grantor, does hereby grant, bargain, sell and convey unto Robert C. Campbell, an
unmarried man, hereinafter referred to as Grantee, whose current address is 3313 W. Cherry Ln
#144, Meridian , ID 83642, the following described premises, situated in Ada County, Idaho, to wit:
LEGAL DESCRIPTION: Real property in the County of Ada, State of Idaho, described as follows:
A parcel of land in Ada County, Idaho, more particularly described as follows:
Beginning at a half inch iron pin that bears South 0114'00" West 443.73 feet from the
Northwest corner of Section 3, Township 3 North, Range 1 West, Boise Meridian, said pin
being on the Section line; thence
South 8904731" East 414.86 feet to the REAL POINT OF BEGINNING; thence
South 8904731" East 256.11 feet; thence
South 5502321" East 155.00 feet; thence
South 64024'03" East 205.31 feet; thence
South 56002'21" East 61.89 feet; thence
North 89047'31" West 621.03 feet; thence
North 0014'00" East 210.00 feet to the REAL POINT OF BEGINNING.
AND EXCEPT any portion thereof lying within right of way of the 8 Mile Lateral.
AND EXCEPT road rights of way.
APN:S1203223480
TO HAVE AND TO HOLD the said premises, with their appurtenances, unto said Grantee, and to the
Grantee's heirs and assigns forever. And the said Grantor does hereby covenant to and with the said
Grantee, that the Grantor is the owner in fee simple of said premises; that said premises are free from all
encumbrances except current years taxes, levies, and assessments, and except U.S. Patent reservations,
restrictions, easements of record and easements visible upon the premises, and that Grantor will warrant
and defend the same from all claims whatsoever.
Page 1 of 2
APN: S1203223450 Warranty Deed File No.: 4102-2664222 (PC)
-continued Date: 05/27/2016
Mich el G. Sorensen
STATE OF Idaho )
ss.
COUNTY OF Ada
Karen L. Sorensen
s' / da of May, 201 before me a Nota Public in and for said State personally appeared
On thi ` Y V, Notary , P Y Pp
Michael G. Sorensen and Karen L. Sorensen, known or identified to me to be the person(s) whose
name(s) i are ubscribed to the within instrument, and acknowledged to me that he/she/ey e- ecuted
the same.
In witness whereof, I have hereunto set my hand and_ affixed my official seal the day and year in this
certificate first above written.
br0ffi6ei u n e a ,Det
®®•• q ®®®®°°° °°®®U�,�°®® Notary Pu is for the State of Idaho
°
�OTARk ® Residing a . Boise, ID
® � My Commission Expires: J
®a®� OF 1960%,
�0aseeieaem�°
Page 2 of 2
AFFIDAVIT OF LEGAL INTEREST
STATE OF IDAHO )
COUNTY OF ADA )
ess)
V� (city) y` f (state)
being first duly sworn upon, oath, depose and say:
That I am the record owner of the property described on the attached, and I grant' my
permission to:
Mnf2t R/,4 /0
(name) (address) 3&
to submit the accompanying application(s) pertaining to that property.
2. I agree to indemnify, defend and hold the City of Meridian and its employees harmless
from any claim or liability resulting from any dispute as to the statements contained
herein or as to the ownership of the property which is the subject of the application.
3. I hereby grant permission to City of Meridian staff to enter the subject property for the
purpose of site inspections related to processing said application(s).
Dated this L Z n day of �'�v+1� 20
SUBSCRIBED AND SWORN to before m
MARTIN D'
NOTARY PUBLIC
IDAHOTATE OF TyJ
e _
/]
Y
Residingat:
My Commission Expires: lsr a a
33 E Broadway Suite 210 • Meridian, Idaho 83642
Phone: (208) 884-5533 • Facsimile: (208) 888-6678 9 Website: www.ineridiancity.org
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E IDIAN Meridian City Hall, Suite 102
33 E. Broadway Avenue
IDAHO Meridian, Idaho 83642
Community Development 208.887.2211
Deportment
Parcel Verification
Date: 2/27/17
The parcel information below has been researched and verified as correct by the City of Meridian
Community Development Department.
Project Name: Geddes Subdivision
Parcel Number: 51203223480
Acres:
T/R/S:
Property Owner
qV
3N 1W 03
Robert C. Campbell
3313 W. Cherry Ln. #144
Meridian, ID 83642
Address Verification Rev: 04/23/12
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ADA COUNTY STREET NAME REVIEW
Preliminary Plat
Review Date: March 29, 2017 Final Plat RX
Project Name: GEDDES SUB T/R/S 3N 1W 03
Parcel Number(s): S1203223480
Project/Plat Applicant: SCHULTZ DEVELOPMENT Phone No: 208-880-1695
City/County Agency: ADA COUNTY -MAOI
THE FOLLOWING EXISTING STREET NAMES SHALL APPEAR ON PLAT
N BLACK CAT RD N GEDDES PL W USTICK RD
Y
Y > 0
Ln LO N U
U) Q -E O
Proposed Street Names: U a o in m Comments
1 N GEDDES PL X E Post type should be "Ave"
2 W SHIRDALE CT X
3 W SHIRDALE ST X
4
5
6
7
8
PLEASE MAKE THE FOLLOWING CHANGES OR CORRECTIONS
Please replace existing street N GEDDES PL with N GEDDES AVE - COUNTY WILL FIX
Please replace N GEDDES PL with N GEDDES AVE
NOTE: If there are corrections and changes recommended, please make these changes on the subdivision plat and
resubmit to the Ada County Assessor. A final review with no changes required and the matching plat must be
presented to the Ada County Surveyor at time of recording.
Codes/criteria regarding denial
A Sounds like an existing street
B Alignment with existing street
C Duplicate street name within Ada County
D Street name exceeds 13 letters
E Other
The overall final street names are subject to change at Final Plat phase levels
due to design changes, time constraints and or previous recorded plat street alignments.
Page 1 of 1
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Breckon Land Design Inc.
Post Office Box 44465
Boise, Idaho 83711
- - i p: 208-376-5153
f: 208-376-6528
www.breckonlanddesign.com
Landscape Architecture • Civil Engineering • Graphic Communication • Erosion Control • Irrigation Design • Land Planning
June 5, 2017
City of Meridian, Community Development Department
33 E. Broadway Ave.
Meridian, ID 83642
Project: Geddes Subdivision
N. Black Cat Rd.
Meridian, ID 83646
Re: Engineers statement of certification
All street finish centerline elevations are set a minimum of three feet above the highest established normal
groundwater elevation, per the attached geotechnical investigation performed by Site Consulting on June 7, 2017.
If you require any additional information or supporting documentation, please let me know.
Sincerely,
Breckon Land Design, Inc.
, G%Sl £N\
��srfRFD�y���
��TTF OF
�TNEW S
Matthew S. Derr, PE
Cc: File
Digitally signed by Matthew S.
Derr, PE
Reason: Document Signature
Date: 2017.06.12 10:40:06 -06'00'
CONSULTING, LLJ
Mr. Matt Schultz June 7, 2017
Schultz Development Page 1 of 2
Post Office Box 1115 File # 17118-B
Meridian, Idaho 83680
Re: Geotechnical Report Addendum #1
Geddes Property
East of 3050 North Blackcat Road
Meridian, Idaho
Matt:
As per you request, SITE has measured the groundwater elevation monthly in the three
wells we installed in March 2017 on the referenced property. We will continue with
month measurements through the end of this irrigation season. Groundwater elevations
to date are listed in the table below.
Location
TP -1
TP -2
TP -3
Casing Height
3.44
3.58
3.79
Hub Elevation
2549.18
2550.28
2550.24
Casing Elevation
2552.62
2553.86
2554.03
311712017
Date Excavated
10.50
2542.12
11.00
2542.86
10.50
2543.53
4/28/2017
Water Elevation
12.15
2540.47
12.44
2541.42
12.51
2541.52
5/30/2017
Water Elevation
10.70
2541.92
10.52
2543.34
10.66
2543.37
Water Elevation
Water Elevation
Highest Measured
Groundwater
2542.12
2543.34
2543.53
We appreciate this opportunity to be of service. Please contact our office if additional
information or services are
Respectfully subm
Bob J. Arnold, PE
SITE Consulting, L
uired.
208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
Z -ITE
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Monitoring WO Location
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Google Earth
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
6/28/2017
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A-
Subject: RE: Geddes "trees"
From: ehuff@meridiancity.org
To: schultzdevelopment@yahoo.com
Date: Wednesday, June 28, 2017,7:08:20 AM MDT
You are good to go. No mitigation. Thanks, Elroy
From: Matthew Schultz
Sent: Wednesday, June 28, 2017 12:02 AM
To: Elroy Huff
Subject: Geddes "trees"
took this pic a few weeks ago
Matt Schultz
(208) 880-1695
City of Meridian
33 E. Broadway Ave., Meridian, Idaho 83642
Phone: 208-888-4433
www.meddiancity.org
All e-mail messages sent to or received by City of Meridian e-mail accounts are subject to the Idaho law, in regards to both release and retention, and may be released
upon request, unless exempt from disclosure by law.
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FINAL HYDROLOGY REPORT
for
GEDDES SUBDIVISION
Address:
N Black Cat Road
Meridian, Idaho
Breckon Land Design, Inc.
6661 N Glenwood Street
Garden City, Idaho 83714
p: (208) 376-5153
f: (208) 376-6528
4 "F OF
THEW S .
Project No. 17034
June 12, 2017
Digitally signed by Matthew S.
Derr, PE
Reason: Document Signature
Date:2017.06.12 10:34:14 -06'00'
Landscape Architecture • Land Planning • Storm Water Management • Erosion Control • Graphic Communication 9 Water Management • Irrigation Design
PURPOSE
The purpose of this report is to confirm that the on-site storm water management system design for the Geddes
Subdivision is adequate for the specified design storms per the City of Meridian, Ada County Highway District
(ACRD) and Idaho Department of Environmental Quality standards.
SITE DESCRIPTION
The subject property is located at N Black Cat Road, lying in Section 3 Township 3 North Range 1 West, Boise
Meridian, City of Meridian, Ada County, Idaho. The limits of construction are approximately 2.1 acres, as
shown on the attached drainage basin map and the construction documents. See Appendix A for the post
development drainage basin map and a copy of the stormwater construction plans.
Currently, the site is gently sloping and runoff from the study area collects drainage is conveyed to the
southwest at an average slope of 0.4% and is ultimately intercepted by the existing N. Geddes Place that
meets the site in the southwest corner. The northeast portion of the site contains the Eight Mile lateral.
Proposed improvements consist of residential buildings, associated structures, utility and roadway
improvements servicing the subdivision. Stormwater draining to the right-of-way in will be captured by
proposed improvements, as described in the post development analysis. All stormwater within the limits of
construction will be contained on site to the extent possible with the addition of the proposed improvements
and on -lot retention of water completed during the building construction.
Soil properties and infiltration rates were obtained from the Geotechnical Recommendation Report for Geddes
Property, by Site Consulting, dated March, 2017 and Appendix #1, dated June, 2017. See Appendix D for a
copy of the report.
DESIGN CRITERIA
ACHD Criteria
The system is designed to accommodate the peak flow for the 25 -year and 100 -year design storm in accordance
with the latest edition of the Ada County Highway District Policy Manual Sections 8000 and 8200. The portions of
the project area draining to the right-of-way utilize the latest edition of spreadsheets provided by ACRD,
equations derived from the spreadsheet and/or the Policy Manual.
The storm water peak runoff flows are calculated using the Rational Method with a weighted post development
runoff coefficient calculated for each drainage area and duration equal to the calculated time of concentration.
The rainfall intensity used was taken from the Boise Area Intensity -Duration -Frequency, with Revised OF Curves
for ACHD as published in Section 8202.1 in the latest edition of the Ada County Highway District Policy Manual
Stormwater Management Design Manual. See Appendix B for a copy of this curve.
The design storm peak volumes are calculated using the Modified Rational Method for a 100 -year, 1 -hour storm
duration. The required pre-treatment volume (defined as the 95th percentile, 24 -hr storm (0.60" in Section
8007.2) is calculated as 0.60 inches over the basin area. This is effectively calculated equivalent to 63% of the
design storm peak volume. The ACRD methodology for pre-treatment volume appears to be conservative by a
factor of at least 4 due to varying methods of calculation (NRCS vs Modified Rational) and storm duration (24-
hour vs 1 -hour) used. The conservative value derived from the ACHD spreadsheet methodology will be used.
PEAK FLOW ANALYSIS OUTLINE
The proposed storm drainage conveyance facilities are sized to provide the necessary capacity to convey the
design storm, as required. The following steps were taken to design the storm conveyance facilities.
1. Calculate the individual drainage basin areas (A), the Runoff Coefficient (C) and Time of
Concentration (Tc) values for the developed basins. Combine basins, as appropriate, to determine
flow at specific Design Points.
2. Determine the peak flow for each basin and Design Point using the Rational Equation (Q=CIA),
utilizing the Rainfall Intensity (1) from the appropriate Intensity -Duration -Frequency curves based on
the Tc value.
3. Verify capacity of the inlets, storm drain lines, sand and grease traps and other storm water
conveyance facilities to accommodate the peak flows.
PEAK FLOW ANALYSIS RESULTS
The proposed storm drainage conveyance system has been sized to accommodate the 100 -year peak flow rates.
All facilities have been verified to adequately pass the peak flow and convey the stormwater to a facility for
disposal by infiltration. See Appendix C for detailed calculations.
DESIGN STORM RETENTION VOLUME ANALYSIS OUTLINE
The proposed storm drainage retention facilities are sized to provide the necessary capacity to store the 100 -
year storm event, to provide for initial settlement of sediments in the runoff and dispose by infiltration within the
required time frame. The following steps were taken to design the storm drain facility.
1. Calculate the individual drainage basin areas (A) and estimate the Runoff Coefficient (C) for the
developed basins. Combine basins, as appropriate, to determine volume at specific Design
Points.
2. Determine the Rainfall Intensity (1) from the appropriate Intensity -Duration -Frequency curves
based on the design storm event and storm duration (T) of one hour.
3. Size the drainage swale per the Modified Rational Method to accommodate the required volume
using the following equation V= C*I*T*A, providing for freeboard and sedimentation.
4. Verify capacity of facilities for design volume and maximum drain time.
100 YEAR RETENTION RESULTS
The proposed drainage facilities have been designed to adequately retain and dispose of the 100 -year design
storm event. See Appendix C for detailed calculations.
PRE- DEVELOPMENT DRAINAGE BASIN AND DESIGN POINT ANALYSIS
A Pre -development analysis was not performed to demonstrate pre -development site conditions, as all drainage
is proposed to be detained on-site to the extent possible. As the design intent is to retain the stormwater
discharge from the project on-site, the off-site discharge will be reduced significantly with the proposed
improvements.
2
POST DEVELOPMENT DRAINAGE BASIN AND DESIGN POINT ANALYSIS
For the Post -development analysis, the drainage patterns for the proposed site have been divided into five (5)
basin areas and five (5) design points as shown in Appendix A. The selected runoff coefficients are a composite
of impervious surfaces (C=0.95) and single family residential lots (C=0.40). Each basin denotes an area of the
project that drains to a specific point defined by a design point. Additional design points are utilized to study
downstream conditions including junctions, drainage basins and outfalls. See Appendix C for detailed
calculations.
Design Point 1 is the point of discharge for Basin A, and, covers approximately 0. 19 acres consisting of mostly
impervious surfaces and lot drainage. Stormwater runoff from Basin A includes sheet flow and gutter flow
draining to a proposed sump inlet. The flow is intercepted by the inlet and directed to the proposed infiltration
basin by the proposed storm sewer. Design flows are routed to Design Point 3.
Design Point 2 is the point of discharge for Basin B, and, covers approximately 0.32 acres consisting of mostly
impervious surfaces and lot drainage. Stormwater runoff from Basin B includes sheet flow and gutter flow
draining to a proposed sump inlet. The flow is intercepted by the inlet and directed to the proposed infiltration
basin by the proposed storm sewer. Design flows are routed to Design Point 3.
Design Point 3 is the point of discharge for Design Points 1 & 2, and, covers approximately 0.51 acres consisting
of mostly impervious surfaces and lot drainage. Stormwater runoff from Design Points 1 & 2 includes sheet flow
and gutter flow directed to the proposed infiltration basin by the proposed storm sewer. Design flows are routed
to and disposed in the proposed infiltration basin. See Appendix C for sizing calculations.
Design Point 4 is the point of discharge for Basins C & D, and, covers approximately 0.36 acres consisting of
mostly impervious surfaces and lot drainage. Stormwater runoff from Basins C & D includes sheet flow and
gutter flow draining to a proposed sump inlet. The flow is intercepted by the inlet and directed to the proposed
infiltration basin by the proposed storm sewer. Design flows are routed to Design Point 5.
Design Point 5 is the point of discharge for Design Point 4 & Basin E, and, covers approximately 0.68 acres
consisting of mostly impervious surfaces and lot drainage. Stormwater runoff from Design Point 4 & Basin E
includes sheet flow and gutter flow directed to the proposed infiltration basin by the proposed storm sewer.
Design flows are routed to and disposed in the proposed infiltration basin. See Appendix C for sizing
calculations.
Appendix A
Drainage Basin Map
Storm Sewer Improvement Plans
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Appendix B
Intensity -Duration -Frequency Curve
BOISE AREA INTENSITY -DURATION -FREQUENCY, WITH REVISED IDF CURVES
Intensity (inches per hour)
Boise Area
Intensity Duration Frequency (IDF)
3.00
------ 2 year
2.50 -*- 5 year
-x- 10 year
E2.00
-ti- 25 year
c1.50 X�\ --0- 50 year
y� X -{ -- 100 year
y1.00 �*\
w \x\
C
.- ---
x0.50 ---. ;;\
0.00
10 min 15 min 30 min 1 hour 2 hours 3 hours 6 hours 12 hours 24 hours
Duration in minutes and hours
ACHD_SD_CALCS_4-21-16 10/11/2016, 8:18 AM
Version 8.7, April 2016 With New IDF Curves
Design Storm
2
5
10
25
50
100
Tc
0.17
10 min
0.69
1.15
1.45
1.85
2.20
2.58
0.25
15 min
0.59
0.97
1.22
1.56
1.86
2.18
0.33
20 min
0.49
0.81
1.01
1.30
1.54
1.81
0.42
25 min
0.43
0.71
0.89
1.14
1.35
1.58
0.50
30 min
0.41
0.67
0.85
1.08
1.29
1.51
0.58
35 min
0.34
0.56
0.70
0.90
1.07
1.25
0.67
40 min
0.31
0.51
0.64
0.82
0.98
1 1.15
0.75
45 min
0.29
0.48
0.60
0.77
0.91
1.07
0.83
50 min
0.27
0.45
0.56
0.72
0.85
1.00
0.92
55 min
0.26
0.43
0.54
0.69
0.82
0.96
1.00
1 hour
0.26
0.43
0.54
0.69
0.82
0.96
2.00
2 hours
0.16
0.25
0.31
0.39
0.46
1 0.54
3.00
3 hours
0.13
0.19
0.23
0.29
0.34
0.40
6.00
6 hours
0.09
0.12
0.14
0.18
0.21
0.25
12.00
12 hours
0.06
0.08
0.10
0.12
0.14
0.16
24.00
24 hours
0.04
1 0.06
1 0.06
0.08
0.09
0.10
Boise Area
Intensity Duration Frequency (IDF)
3.00
------ 2 year
2.50 -*- 5 year
-x- 10 year
E2.00
-ti- 25 year
c1.50 X�\ --0- 50 year
y� X -{ -- 100 year
y1.00 �*\
w \x\
C
.- ---
x0.50 ---. ;;\
0.00
10 min 15 min 30 min 1 hour 2 hours 3 hours 6 hours 12 hours 24 hours
Duration in minutes and hours
ACHD_SD_CALCS_4-21-16 10/11/2016, 8:18 AM
Version 8.7, April 2016 With New IDF Curves
Appendix C
Storm Water Calculations
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 Geddes Subdivision, Basin A, Design Point 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) 25
4 Enter number of storage facilities (25 max) 7
Click to Show More Subbasins 0
5 Area of Drainage Subbasin (SF or Acres) Acres
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 c int J
Subbasin
1.85
Subbasin
Subbasin
Subbasin
cis
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.10
0.09
Heavv areas
090
0.19
0.95
0.40
0.69
8 Determine the average rainfall intensity (i) from IDF Curve based on
9 Calculate the Post -Development peak discharge (QPeak)
10 Calculate total runoff vol (V) (for sizing primary storage)
V = Ci(Tc=60)Ax3600
11 Calculate Volume of Runoff Reduction Vrr
Enter Percentile Storm I (95th percentile = 0.60 in)
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C)
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
13 Volume Summary
Surface Storage: Basin
Basin Forebay
Primary Treatment/Storage Basin
Subsurface Storage
Volume With 15` o Sediment Factor
1
1.85
in/
Qp..k
0.24
cis
Urban neighborhoods
0.50-_0.70
Residential
V
325
ft
Multi -family
------ ----
.0.600.75
-------------------------
95th
0.60 in
Vrr
283
ft'
Light areas
cfs
Type of Surface
Runoff Coefficients "t
Business
Downtown areas
0,70-0.95
Urban neighborhoods
0.50-_0.70
Residential
Brick
Single Family
0.35.0.50
Multi -family
------ ----
.0.600.75
-------------------------
Resldential (rural)_ ____ ............
0_25-0.40
ApartmentOwelling Areas
0 70
Industrial and Commercial
Light areas
0.$o
Heavv areas
090
fta
ovrea .
V 33
Concrete
V 293
W
Brick
Roofs
ft'
_Gravel
V 374
fields: Sar
Slope
Flat: O.2%
Average::
0.95
0.95
A B C D
0.04 0.07 0.11
0.09 0.12 0.15
0.13 0.18 0.23 O::
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16 5/31/2017,1:51 PM
Version 9.0, December 2016
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 Geddes Subdivision, Basin 8, Design Point 2
2
2 Is area drainage basin map provided? YES
(map must be included with stormwater calculations)
3 Enter Design Storm (100 -Year or 2S -Year With 100 -Year Flood Route) 25
5 Area of Drainage Subbasin (SF or Acres) Acres
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 1 User calculate
min [io -7.11_
int
rtirir to Chn Mnre Snhha li I1
Subbasin
I Runoff Coefficients "C
Subbasin
Subbasin
Subbasin
0.70-0.45
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.14
0.18
0.32
0.95
0.40
0.64
8 Determine the average rainfall intensity (i) from IDF Curve based on
9 Calculate the Post -Development peak discharge (QPeak)
10 Calculate total runoff vol (V) (for sizing primary storage)
V = Ci(Tc=60)Ax3600
11 Calculate Volume of Runoff Reduction Vrr
Enter Percentile Storm I (95th percentile = 0.60 in)
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C)
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
13 Volume Summary
Surface Storage: Basin
Basin Forebay
Primary Treatment/Storage Basin
Subsurface Storage
Volume With 15% Sediment Factor
Q* .k 0.38 cfs
V 509 ft
95th 0.60 in
V„ 443 ft,
cfs
V 51 ft'
V 458 fts
V 586 W
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surface
Type of Surface
I Runoff Coefficients "C
Business
Downtown areas
0.70-0.45
neighborhoods_
0.50-0.7o
_Urban
Residential
Single Family
0.35.0.50
_Multbfamily_
0.60.0.75
Residential (rural)
0-25.0.40
Apartment Dwelling Areas_
_
Industrial and commercial
Light areas
a.ao
Streets
Asphalt
Concrete
Slope
Flat: 0-2%
Average: 2-6%
0,95
0.95
Soil Type
A I B C 0
0.04 0.07 0.11 0,:
o.09 0.12 0.15 0.;
0.13 0,18 0.23 0.:
5/31/2017, 1:51 PM
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 Geddes Subdivision, Basins A&B, Design Point 3
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) 25
5 Area of Drainage Subbasin (SF or Acres) Acres
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 1 User calculate
min rio mi,,
Click to Show More Subbasins ❑
Subbasin
i
Ctae,k
Subbasin
Subbasin
Subbasin
V
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.24
0.27
726
W
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
0.95
Brick
cfs
13 Volume Summary
0.51
Surface Storage: Basin
Basin Forebay
V
83
fts
0.95
0.40
751
ft'
Subsurface Storage
Volume With 15% Sediment Factor
V
0,66
W
8 Determine the average rainfall intensity (i) from IDF Curve based on
9 Calculate the Post -Development peak discharge (4Peak)
i
Ctae,k
1.85
0.62
in/hr
cfs
10 Calculate total runoff vol (V) (for sizing primary storage)
V
835
ft
V = Ci (Tc=60)Ax3600
Railroad yard areas
11 Calculate Volume of Runoff Reduction Vrr
t1n]mproved areas
.:_.:._._ ... ............
Enter Percentile Storm I (95th percentile = 0.60 in)
Streets
95th
0.60 in
Enter Runoff Reduction Vol 195th Percentile=0.60-in x Area x C)
Vr,
726
W
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
0.95
Brick
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
83
fts
Primary Treatment/Storage Basin
V
751
ft'
Subsurface Storage
Volume With 15% Sediment Factor
V
960
W
S:`projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surfac<
Type of Surface Runoff Coefficients "C
Business
Downtown areas 0.70-0.95
Wban_neighb_orhoods 0.50.0.70
Residential
Single Family 0 35 0.50
Multi -family 0600.75_
Residential (ruralV 0.25-0.40
Light areas
0.80
Heavy areas
0.90
Parks, cemeteries
0.10
Railroad yard areas
t1n]mproved areas
.:_.:._._ ... ............
t0,20
0.10
____.....
Streets
Asphalt
.0.95
Concrete
0.95
Brick
.0.95
Slope
Flat: 0 -try
Average: 2-6%
Steep:>6
Adapted from ASCE
Sol] Type
A B C ()
0-040.17 0.11
0.09 0,12 0.15
0.13 0.18 0.23 0.:
5/31/2017,1:51 PM
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 Geddes Subdivision, Basin C
4
2 Is area drainage basin map provided? YES
(map mustbe included with stormwater calculations)
3 Enter Design Storm (100 -Year or 25 -Year With 100 -Year Flood Route) 25
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre.
6 Determine the Weighted Runoff Coefficient (C)
C=[(CSxAl)+(C2xA2)+(CnxAn))/A Weighted Avg
7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 User calculate
min
rllrk to Shnw Mnre Suhhaslns n
Subbasin
Runoff Coefficients "<
Subbasin
Subbasin
Subbasin
0.70-0.95
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.12
0.02
Heavy areas
0.90
0.14
0.95
0.40
0.87
8 Determine the average rainfall intensity (i) from IDF Curve based on
9 Calculate the Post -Development peak discharge (C.Peak)
10 Calculate total runoff vol (V) (for sizing primary storage)
V = Ci(Tc=60)Ax3600
11 Calculate Volume of Runoff Reduction Vrr
Enter Percentile Storm I (95th percentile = 0.60 in)
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C)
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
13 Volume Summary
Surface Storage: Basin
Basin Forebay
Primary Treatment/Storage Basin
Subsurface Storage
Volume With 15% Sediment Factor
Q,.k 0.23 cis
V 303 ft
95th 0.60 in
V„ 264 ft,
cfs
V 30 W
V 273 fts
V 349 ft'
5:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
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
_Apartmary Dwelling Areaz
0.70 _-
Industrial and Commercial
Light areas
0.80
Heavy areas
0.90
Asphalt
Concrete
Fields: Sandy soil
Slope
Flat! 0.2%,
Average: 2-6%
0.95
0.95
Soil Type
A B C 0
0.04 0.07 0.11 0::
0.09 0.12 0:15 0.:
0.13 0.18 0.23 0.:
5/31/2017,1:51 PM
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 Geddes Subdivision, Basin D
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) 25
5 Area of Drainage Subbasin (SF or Acres) Acres
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 default 10 1 User Calculate
min 10'Min.
[lick to Show More Subbasins F1
Subbasin
1.85
Subbasin
Subbasin
Subbasin
cfs
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
30
0.11
0.11
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
Industrial and Commercial
_02_0
0.22
0.80
Heavy areas
0.90
Parks, Cemeteries
0.10.0.25
Playgrounds
0.95
0.40
Railroad card areas
—i
0 ZO 0.40
0.68
8 Determine the average rainfall intensity (i) from IDF Curve based on 1
1.85
in/hr
9 Calculate the Post -Development peak discharge (QPeak) (beak
0.27
cfs
Downtown areas-
0.70-0.95
10 Calculate total runoff vol (V) (for sizing primary storage) V
369
ft
V = Ci(Tc=60)Ax3600
_
I
11 Calculate Volume of Runoff Reduction Vrr
35 0.50
0":'
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) Vol321
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay V 37 ft'
Primary Treatment/Storage Basin V 332 W
Subsurface Storage
Volume With 15% Sediment Factor V 424 W
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
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
_
I
Single Family:
35 0.50
0":'
Multi -family
}IL 11:6. 0.75
Residential Qural
0 25-0.40 — — —
Apartment Dwelling Areas
Industrial and Commercial
_02_0
Light areas
0.80
Heavy areas
0.90
Parks, Cemeteries
0.10.0.25
Playgrounds
Railroad card areas
—i
0 ZO 0.40
Streets
Asphalt
Concrete
Brick
Fields; Sandy soil
Slope
Flat: 0.2%
Average: 2-6%.
0.95
0;95
0.95
Soil Type
A B E D
0.04 0.07
0.09 0,12
0,13 0.18 0.23 O.:
5/31/2017,1:51 PM
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 Geddes Subdivision, Basin C&D, Design Point 4
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) 25
5 Area of Drainage Subbasin (SF or Acres) Acres
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 1 User calculate
min 79
`!n:�
Click to Show More Subbasins ❑
Subbasin
(� 1
Cy..k
Subbasin
Subbasin
Subbasin
V
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.23
0.13
584
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
0.36
Surface Storage: Basin
Basin Forebay
V
67
ft'
0.95
0.40
605
ft'
Subsurface Storage
Volume With 1S% Sediment Factor
V
0.75
W
8 Determine the average rainfall intensity (i) from IDF Curve based on
9 Calculate the Post -Development peak discharge (QPeak)
(� 1
Cy..k
1.85
0.50
cfs
10 Calculate total runoff vol (V) (for sizing primary storage)
V
672
ft
V = Ci (Tc=60)Ax3600
0,95
Brick
0.95
11 Calculate Volume of Runoff Reduction Vrr
0.13 0:18
0.23' 0..
Adapted from ASCE
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„
584
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
67
ft'
Primary Treatment/Storage Basin
V
605
ft'
Subsurface Storage
Volume With 1S% Sediment Factor
V
773
W
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surface
Type of Surface Runoff Coefficients "t
Business
Downtown areas 0.70-0.95
_
Urban neighborhoods 0.500.70
Residential ------- —_ —
Single Family: 0.35.0.50
_Multi -family 0.60.0.75
Residential (rural) 0.25-0.40
Light areas 10:80
I Railroad yard areas
1 0.20
........_.._..._.._.......___.._.__..__ ..............
lJnimproved areas
.,.........
.010
Streets
Asphalt
0.95
Concrete
0,95
Brick
0.95
Fields: Sandy soil
Soil Type
Slope
-A—__ 8...__:_
Flat: 04%
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
5/31/2017,1:51 PM
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 Geddes Subdivision, Basin C, D & E, Design Point 5
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) 25
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre.
6 Determine the Weighted Runoff Coefficient (C)
C=[(ClxA1)+(C2xA2)+(CnxAn)j/A Weighted Avg
7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 1 User calculate
min �10 Mi i.
_ ..... ............�
rlir4 to Chnu, Mnrn Ciihha<inc I1
Subbasin
1
Subbasin
Subbasin
Subbasin
Qpeak
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.28
0.40
Heavv areas
0.90.
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)
Vr,
0.68
W
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
0.95
0.40
Basin Forebay
V
106
ft'
Primary Treatment/Storage Basin
V
0.63
ft°
Subsurface Storage
Volume With 15% Sediment Factor
V
1,217
ft'
8 Determine the average rainfall intensity (i) from IDF Curve based on
1
1.85
in/hr
9 Calculate the Post -Development peak discharge (QPeak)
Qpeak
0,79
cfs
_ _
Residential
_
l
SingleFamily
0350.50
10 Calculate total runoff vol (V) (for sizing primary storage)
V
1,058
ft
V = Ci(Tc=60)Ax3600
0.70
Industrial and Commercial
11 Calculate Volume of Runoff Reduction Vrr
080
Heavv areas
0.90.
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)
Vr,
920
W
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
106
ft'
Primary Treatment/Storage Basin
V
952
ft°
Subsurface Storage
Volume With 15% Sediment Factor
V
1,217
ft'
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surfac<
Type of Surface
I Runoff Coefficients "t
Business
Downtown areas
0.70-0.95
Urban neighborhoods_
0.50.0.70_
_ _
Residential
_
l
SingleFamily
0350.50
Multi-family--I{I�0
Multi-
60 0.75
Residential (rural)
0.25-0.40 -
Apartment Owe0Ing Areas
0.70
Industrial and Commercial
Light areas
080
Heavv areas
0.90.
Streets
Asphalt
Concrete
Brick
Roots
G_r_a_vei _
Fields: Sandy soil
Slope
Flat: 0.29$
Average: 2-6%.
Steep:>6%
__...___ ___.............
_..._.
Adanted from ASCE
0,95
0:95
A B C 0
0.04 0.07 0.11 0::
0.09 0.12 0:15
0.13 018 0.23 0.:
5/31/2017,1:51 PM
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 Geddes Subdivision, Basin A, Design Point 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) 7
Click to Show More Subbasins ❑
5 Area of Drainage Subbasin (SF or Acres) Acres
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
Subbasin
i
Subbasin
Subbasin
Subbasin
/�
O* .k
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.10
0.09
Enter Percentile Storm t (95th percentile = 0.60 in)
95th
0.60 in
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C)
Vrr
0.19
W
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
0.95
0.40
Basin Forebay
V
45
WPrimary
Treatment/Storage Basin
V
0.69
W
Subsurface Storage
Volume With 15% Sediment Factor
V
521
W
8 Determine the average rainfall intensity (i) from IDF Curve based on
i
2.58
in/hr
9 Calculate the Post -Development peak discharge (CiPeak)
/�
O* .k
0.34
cfs
Single Family
0.35.0.50
Multi -family-__
-------------------
0.60.0.75
10 Calculate total runoff vol (V) (for sizing primary storage)
V
453
it
V = Ci (Tc=60)Ax3600
Light areas
0.80
11 Calculate Volume of Runoff Reduction Vrr
0.90
Enter Percentile Storm t (95th percentile = 0.60 in)
95th
0.60 in
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C)
Vrr
283
W
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
45
WPrimary
Treatment/Storage Basin
V
407
W
Subsurface Storage
Volume With 15% Sediment Factor
V
521
W
S:`,projects\2017\17034 Geddes Sub\Admin\Reports\SW\Caiclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
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
Resid6ntinl (rurai�
0.25.0.40
_Apartment_Dwelling Areas
_0.70___ d�
Industrial and Commercial
Light areas
0.80
Heavv areas
0.90
Streets
Asphalt
Concrete
Slope
Plat: 0-2`90
Average: 2.6%
0.95
0.95
A6 C D
0.04 0.07 0.11 0.'
0.09 0.12 0.15 0.;
0.13 0.18 0.23 0::
5/31/2017, 1:50 PM
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 Geddes Subdivision, Basin B, Design Point 2
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
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre:
6 Determine the Weighted Runoff Coefficient (C)
C=[(C1xAl)+(C2xA2)+(CnxAn)]/A Weighted Avg
7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 Usercalculate
min �to 4i..
111,4 - chnu, AA— 4ihkxinc n
Subbasin
i
Subbasin
Subbasin
Subbasin
QPeA
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
30
0.14
0.18
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)
Vr,
0.32
ft -
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
0.95
0.40
Basin Forebay
V
71
ft'
Primary Treatment/Storage Basin
V
0.64
ft'
Subsurface Storage
Volume With 1S% Sediment Factor
V
815
ft'
8 Determine the average rainfall intensity (i) from IDF Curve based on
i
2.58
in/hr
9 Calculate the Post -Development peak discharge (QPeak)
QPeA
0.53
cis
10 Calculate total runoff vol (V) (for sizing primary storage)
V
708
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)
Vr,
443
ft -
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
71
ft'
Primary Treatment/Storage Basin
V
638
ft'
Subsurface Storage
Volume With 1S% Sediment Factor
V
815
ft'
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surfaca
Type of Surface Runoff Coefficients"(
Business
Downtown areas 0.70-0.95
urban neighborhoods 0.500.70
Residential
Single Family: 0.35.0.50
areas 0.80
r areas 0.9Q
Cemeteries 0.10
roundsul 0.20
gad yard areas 10,20
Asphalt
Concrete
Brick
Fields: Sandy soil
Slope
Flat: 0.2`Yr,
Average: 2-6Yo
Steep:>6% _
Adapted from ASCE
0,95
Soil Type
A 6 C Q
0.040.07 0.11
0.09 0.12 0:15
0.13 0.18 0.23 0.:
5/31/2017,1:50 PM
ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method
NOTE: This worksheet is intended to be a guideline to standardize ACRD 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 Geddes Subdivision, Basins A&B, Design Point 3
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
5 Area of Drainage Subbasin (SF or Acres) Acres
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 r1911,1
seM6r cakuiate
min to ,� ?
rlirk to Chnw Mora Suhhadns rl
Subbasin
2.58
Subbasin
Subbasin
Subbasin
cfs
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.24
0.27
726
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
0.80
cis
Heavy areas
0.90
0.51
0.10.0.25
Playgrounds
Railroad yard areas
I 0 20 0.40
Unimproved areas.
0.95
0.40
Streets
Asphalt
9.95
Concrete
0.95
0.66
Brick
.0:95
_-�
Roofs
0.95
8 Determine the average rainfall intensity (i) from IDF Curve based on 1
2.58
in/hr
r�
9 Calculate the Post -Development peak discharge (CiPeak) 0,p .k
0.87
cfs
Residential
10 Calculate total runoff vol (V) (for sizing primary storage) V
1,161
ft
V = Ci(Tc=60)Ax3600
0.60-0.75
_
it Calculate Volume of Runoff Reduction Vrr
0.25-0.40
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
726
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
0.80
cis
13 Volume Summary
Surface Storage: Basin
Basin Forebay
Primary Treatment/Storage Basin
Subsurface Storage
Volume With 15% Sediment Factor
V 116 fti
V 1,045 W
V 1,335 ft'
S:`projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS 12-15-16
Version 9.0, December 2016
�Estimated Runoff Coefficients for Various 5urfac(
Tl voe of Surface I Runoff Coefficients "t
Downtown areas
0.70-0.95
Urban neighborhoods
0.50.0.70
Residential
Single Family
0.35x0.50
Multifamily _
0.60-0.75
_
Residential rural
0.25-0.40
Apartment Owelling_Area_s_--
0.70------
-
Industrial and Commercial -
--
Light areas
0.80
Heavy areas
0.90
Parks, Cemeteries
0.10.0.25
Playgrounds
Railroad yard areas
I 0 20 0.40
Unimproved areas.
0.10.0.30
Streets
Asphalt
9.95
Concrete
0.95
Brick
.0:95
_-�
Roofs
0.95
Fields; Sandy soil
_____...........-.-___.._
Soli Type
Slope
A B
C 0
Flat: 0.2%
004 007
0.11 0'
Average: 2-6%.
0 09 0 12
0.15 0.:
6t.->6%
013 O S$
0:23 0.:
5/31/2017, 1:S0 PM
ACHD Calculation Sheet for Finding Peak Discharge/Volume - Rational Method
NOTE: This worksheet is intended to be a guideline to standardize ACHO 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 Geddes Subdivision, Basin C
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
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre
6 Determine the Weighted Runoff Coefficient (C)
C=[(C1xAl)+(C2xA2)+(CnxAn))/A Weighted Avg
7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 luserCalculate
min to Kelp, 1
Click to Show More Subbasins f
Subbasin
1
Subbasin
Subbasin
Subbasin
Qp.k
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.12
0.02
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
0.14
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
0.95
0.40
Basin Forebay
V
42
ft'
Primary Treatment/Storage Basin
V
0.87
ft'
Subsurface Storage
Volume With 1S% Sediment Factor
V
48S
ft'
8 Determine the average rainfall intensity (i) from IDF Curve based on
1
2.58
in/hr
9 Calculate the Post -Development peak discharge (QPeak)
Qp.k
0.31
cfs
10 Calculate total runoff vol (V) (for sizing primary storage)
V
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)
Vrr
264
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
42
ft'
Primary Treatment/Storage Basin
V
379
ft'
Subsurface Storage
Volume With 1S% Sediment Factor
V
48S
ft'
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CAICS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Sur fact
Type of Surface Runoff Coefficients "C
Business
Downtown areas 0,70-0.95
Urban neighborhoods 0.50.0.70
Residential
Single Family 0.35,0.50
Mitlti•family_ _ _0.60-0.75 ________-___________
------
-Residential (rural) _ 0.25-0.4.0 _
Apartment Dwelling Areas 0,70
Industrial and Cot 'cial
Light areas 0.80
Heavv areas 0.90
Asphalt 0.95
Concrete 0,95
Brick 0.95
Fields: Sandy soil I Soil Type
Slope A B C D
Flat: 0-2% 0.04 .0.07 0.11 0.'
Average: 2-6% 0.09 0.12 OAS 0.;
*--Aly - 0.13 0.18 0.23 0.:
5/31/2017,1:50 PM
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 Geddes Subdivision, Basin D
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
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre.
6 Determine the Weighted Runoff Coefficient (C)
C=[(C1xA1)+(C2xA2)+(CnxAn)]/A Weighted Avi
rlirk to Shnw Mnre Suhhaslns n
Subbasin
ISubbasin
In/hr
Subbasin
Subbasin
cfs
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
30
0.11
0.11
321
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
0.10.0.25
cfs
__-... _...
_0q
Railroad yard areas
0.20-0.40
0.22
0.95
0.40
0.68
7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 User Calculate
min tonin:
8 Determine the average rainfall intensity (i) from IDE Curve based on1
2.58
In/hr
(�
9 Calculate the Post -Development peak discharge (QPeak) C pe.k
0.38
cfs
urban neighborhoods
0,500.70
Residential
10 Calculate total runoff vol (V) (for sizing primary storage) V
513
ft
V = Ci(Tc=60)Ax3600
0,60-0,75
Residential rural
11 Calculate Volume of Runoff Reduction Vrr
_Apartment Owelng Areas
0.70
Enter Percentile Storm 1(95th percentile = 0.60 in)
95th
0.60 in
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C) Vrr,
321
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
0.10.0.25
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay V 51 W
Primary Treatment/Storage Basin V 462 W
Subsurface Storage
Volume With 15% Sediment Factor V 590 ft'
Sc\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surfact
Type of Surface
Runoff Coefficients "t
Business
Downtown areas
0.70-0.45
urban neighborhoods
0,500.70
Residential
Single Family.
0.35.0.50
Multbfamii�
0,60-0,75
Residential rural
0.25-0,40
_Apartment Owelng Areas
0.70
Industrial and Commercial
Light areas
0.80
Heavy areas
0.90
Parks, Cemeteries
0.10.0.25
_ ou -...� _ . __,..
Playgrounds
__-... _...
_0q
Railroad yard areas
0.20-0.40
Streets
Asphalt
Concrete
Brick
Roofs_
Fields; Sandy soil
slope
Flat: 0.2%
Average: 2-6%
0.95
0,95
0.95
Soil Type
A B C D
0.04 0.07 0.11 0.'
0.09 0.12 0.15 0.:
0.13 0.18 0.23 0.:
5/31/2017,1:50 PM
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 Geddes Subdivision, Basin C&D, Design Point 4
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
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre!
6 Determine the Weighted Runoff Coefficient (C)
C=[(ClxAl)+(C2xA2)+(CnxAn))/A Weighted Avg
7 Calculate Overland Flow Time of Concentration in Minutes (Tc) or use default 10 us r[akufate
min o R4iii:�
rlir4 to chew Mnrn oihhacin< rI
Subbasin
Runoff Coefficients "C
Subbasin
Subbasin
Subbasin
70-0.95
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.23
0.13
Heavv areas
0.90
0.36
0.95
0.40
0.75
8 Determine the average rainfall intensity (i) from ]OF Curve based on
9 Calculate the Post -Development peak discharge (QPeak)
10 Calculate total runoff vol (V) (for sizing primary storage)
V = Ci(Tc=60)Ax3600
it Calculate Volume of Runoff Reduction Vrr
Enter Percentile Storm I (95th percentile =0.60 in)
Enter Runoff Reduction Vol (95th Percentile=0.60-in x Area x C)
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
13 Volume Summary
Surface Storage: Basin
Basin Forebay
Primary Treatment/Storage Basin
Subsurface Storage
Volume With 15% Sediment Factor
Q.pezk 0.70 cfs
V 935 ft
95th 0.60 in
Vrr 584 W
cfs
V 93 W
V 841 fts
V 1,075 W
S:`projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD CALCS_12-15-16
Version 9.0, December 2016
Estimated Runoff Coefficients for Various Surfac(
Type of Surface
Runoff Coefficients "C
Business
Downtown areas0
70-0.95
Urban neighborhoods
0 50.0.70
Residential
Single Family;
0.35.0.50
Multi -family
0,60-0.7S
------------
Residential (rural)
—
0.25-0.40
Apartment Dwelling Areas
—0,T0 -
70Industrial
Industrial and Commercial
Light areas
0.80
Heavv areas
0.90
( Asphalt
slope
Flat: 0-2%
Average: 2-691
0,95
0.95
AB C 0
0.04 0-07 0.17. 0::
0.09 0.12 0.15 0.;
0.13 0.18 0.23 0.:
5/31/2017,1:50 PM
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 Geddes Subdivision, Basin C, D & E, Design Point 5
7
2 Is area drainage basin map provided? YES
(map mustbe included with stormwater calculations)
3 Enter Design Storm (100 -Year or 25 -Year With 100 -Year Flood Route) 100
5 Area of Drainage Subbasin (SF or Acres) Acres
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 1 User calculate
Cto hrjn;�-�
min [
flick in Shnw Mnre 9ihha<in< n
Subbasin
V
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
Subbasin 6
7
8
9
10
0.28
0.40
cfs
13 Volume Summary
Surface Storage: Basin
0.68
Basin Forebay
V
147
ft'
Primary Treatment/Storage Basin
V
1,325
ft'
0.95
0.40
Volume With 15% Sediment Factor
V
1,693
ft'
0.63
8 Determine the average rainfall intensity (i) from IDF Curve based on (� 1 2.58 in/I
9 Calculate the Post -Development peak discharge (QPeak) Q,..k 1.10 cfs
10 Calculate total runoff vol (V) (for sizing primary storage)
V
1,472
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,r
920
ft'
12 Detention: Approved Discharge Rate to Surface Waters (if applicable)
cfs
13 Volume Summary
Surface Storage: Basin
Basin Forebay
V
147
ft'
Primary Treatment/Storage Basin
V
1,325
ft'
Subsurface Storage
Volume With 15% Sediment Factor
V
1,693
ft'
5:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16
Version 9.0, December 2016
nated Runoff Coefficients for Various
10
Downtotyn areas 11:70-0:95 70-0.95
Urban neighborhoods 0,.7.
Residential --- -------
Single Family 0 35.0.50
Light areas
Streets
Asphalt .0.95
Concrete 0.95
Brick 0.95
Fields: Sandy soil. I Soil Type
Slops
A B
Flan 0-2% 0 040.07 0 11 0.:
Average 2-6% 0 09 0.12 0.15. 0.;
Steep:>6%_ 013 0.18 0.23 0.:
Adapted from ASCE
5/31/2017, 1:50 PM
ACHD Calculation Sheet for Sizing Basins
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 Sizing Basins: Size for forebay and print then size for primary storage/treatment basin.
User input in yellow cells.
1 Project Name Geddes Subdivision, Basins A&B, Design Point 3
truer numoer or uasins fro maxi c
3 Number of Cells (Forebay+Primary=2, Primary Only=1) 1
4 Design Storm 100 '0, y3'
5 Weighted Runoff Coefficient C 0.66
6 Area A (Acres) 0.51 acres
7 Approved Discharge Rate (if applicable) 0.00 cis
8 1 -Basin Forebay V 1,161 it
Toggle between Forebay and Primary Basin, enter data and print far each
sac sole z
A qw
'' Sa4 S}4et
< -----------L ----- -9. $ik$14,L
Forebay
9 Select Forebay Shape 5 -Irregular
10 Width of Forebay Bottom W 5.0 ft
11 Length of Forebay Bottom L 55.0 ft
12 Side Slopes (H:1) H:1 3.00
13 Enter Bottom Elevation
14 Enter Top Bank Elevation
15 Enter Water Surface Elevation (WSE)
16 Distance Between Forebay and Primary Basin (blank if na)
17 Enter Elevation Berm
18 Enter High Groundwater Elevation
19 Min. Freeboard Requirement
20 Freeboard Provided
21 Infiltration Area for Forebay Infiltration?
Design Infiltration Rate, Enter 0 for no infiltration
22 Infiltration Area for Forebay Asand
Enter 0 for no infiltration
23
2548.60 ft
2548.10 it
0.00 ft
0.00 it
0.00 it
Link to: IQvN
QY>'
': Qv4
4Vs
;OV6
3 iuvl
(QV iRSS
su<suye:
f1BV
wC: %
�L
0.50
Basin
Side Slope Width at
New Stage (ft) (H:V) Stage (ft)
8.00
in/hr
Ir.
NZ
Note: infiltration required if
bottom slope<l%or 0 outflow
IStorm Duration l f total I Q (RunoffVoll Perc Vol I -l- l -Total I Max Vol
24 ( 0 i 24
Saved Stage
(ft)
Basin
Side Slope Width at
New Stage (ft) (H:V) Stage (ft)
Basin
Length at
Stage (ft)
Surface
Area A at
Stage ft)
Saved
Surface
Area A at
Stage (ft)
Surface
Area A at Volume
Stage (ft) Below Stage
OVERIDE (ft')
2545.60
2545.60 3.000
5.0
55.0
Override
0.00
0
2546.00
3.000
0.0
0.0
Override
164.00
33
2546.50 1
3.000
1 0.0
0.0 1
Override
335.00
158
2547.00
3.000
0.0
0.0
Override
524.00
372
2547.50
3.000
0.0
0.0
Override
733.00
687
2548.00
3.000
0.0
0.0
Override
968.00
1,112
2548.10
3.000
0.0
0.0
Override
1021.00
1,211
2548.50
3.000
0.0
0.0
Override
1233.00
1,662
0.00
0.00
0
0.00
0.00
0 ll
0.00
0.00
0
2.90 it depth for storage
25 Does forebay have capacity?
26 Time to drain forebay
90% volume in 48 -hours minimum
YES
43.5 hours
OK
aIUKAEA UK
S:LProjects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16 5/31/2017, 1:51 PM
Version 9.0, December 2016
ACHD Calculation Sheet for Sizing Basins
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 Sizing Basins: Size for forebay and print then size for primary storage/treatment basin.
User input in yellow cells.
1 Project Name Geddes Subdivision, Basin C, D & E, Design Point 5
2
toter numcer or basins to maxi
3 Number of Cells (Forebay+Primary=2, Primary Only=1) 1
4 Design Storm 100 '0, y7'
5 Weighted Runoff Coefficient C 0.63
6 Area A (Acres) 0.68 acres
7 Approved Discharge Rate (if applicable) 0.00 cis
8 1 -Basin Forebay V 1,472 ft'
Toggle between Foreboy and Primary Basin, enter data and print for each
S�SbteL Stir SiereZ
t
A -_fin.,
A
Y yam/'
' Sfb57geL
L <------- .,..,�........... SiIt SlgeZ
Forebay
9 Select Forebay Shape 5 -Irregular
10 Width of Forebay Bottom W 5.0 it
11 Length of Forebay Bottom L 55.0 ft
12 Side Slopes (H:1) H:1 3.00
13 Enter Bottom Elevation 2546.90 it
14 Enter Top Bank Elevation 2549.50 it
15 Enter Water Surface Elevation (WSE) 2549.00 it
16 Distance Between Forebay and Primary Basin (blank if na) 0.00 it
17 Enter Elevation Berm 0.00 ft
18 Enter High Groundwater Elevation 0.00 it
19 Min. Freeboard Requirement 0.50
20 Freeboard Provided 0.50
Link to: o.v •'`
Qvz
QV3 y
Q.V4
4.V5
QV6
�0,v7-�
,QV TR5S
Sae Styei
�'Y L n.
W1
E. \�55d¢/$ipez
L
21 infiltration Area for Forebay Infiltration? 8.00 in/hr Note; infiltration required if
Design Infiltration Rate, Enter 0 for no infiltration bottom slope<I%or 0outflow
22 Infiltration Area for Forebay Asad 42 ftz
Enter 0 for no infiltration
23 Adjusted Storage Required
Storm Duration I i total I Q Runoff Vol Perc Vol fm -D- _.Total Max Vol
60
Lam!
Saved Stage
(ft)
Basin
Side Slope Width at
New Stage (it) (H:V) Stage (ft)
Basin
Length at
Stage (ft)
Surface
Area A at
Stage (it')
Saved
Surface
Area A at
Stage (ft)
Surface
Area A at Volume
Stage yt) Below Stage
OVERIDE (ft)
2546.90
2546.90 3.000
5.0
55.0
Override
42.00
0
2547.00
3.000
0.0
0.0
Override
92.00
7
2547.50 1
3.000
1 0.0
0.0
Override
558.00
169
2548.00
3.000
0.0
0.0
Override
751.00
496
2548.50
3.000
0.0
0.0
Override
963.00
925
2549.00
3.000
0.0
0.0
Override
1195.00
1,464
2549.50
3.000
0.0
0.0
Override
1453.00
2,126
0.00
0.00
0
0.00
0.00
0
0.00
0.00
0
0.00
0.00
0
2.60 ft depth for storage
25 Does forebay have capacity?
26 Time to drain forebay
90% volume in 48 -hours minimum
YES
47.3 hours
OK
51UKAGE UK
S:\_projects\2017\17034 Geddes Sub\Admin\Reports\SW\Calclulations\ACHD_SD_CALCS_12-15-16 5/31/2017, 1:51 PM
Version 9.0, December 2016
Appendix D
Geotechnical Report
XSITE
CONSULTING, LLC
Mr. Matt Schultz Revised April 13, 2017
Schultz Development March 27, 2017
Post Office Box 1115 Page 1 of 14
File # 17118-A
Meridian, Idaho 83680
Re: Geotechnical Recommendation Report
Geddes Property
East of 3050 North Blackcat Road
Meridian, Idaho
Matt:
Laboratory test results have been added to our original report. There are no changes to
the recommendations within this report.
As per your authorization, on March 17, 2017, SITE personnel logged and sampled
three test pits on your Geddes Property and generated the following geotechnical
recommendations. The test pits were excavated on a single parcel located east of 3050
North Blackcat Road in Meridian, Idaho. A tax parcel number of S1203223480 was
located for the parcel on the Ada County Assessor's website. This source indicates the
property includes a total of 2.0 acres.
Preliminary plans, supplied by the client, indicate that the proposed subdivision will
include a short ACHD right of way and approximately nine lots for single-family
residences. Current plans include subsurface infiltration trenches for storm water
disposal.
Based upon our research, observations, and laboratory test results, the site is
acceptable for development as a residential subdivision. Recommendations for
construction are included herein. We appreciate this opportunity to be of service.
When appropriate, we would like to discuss continuing our role as geotechnical
consultant during construction. Please contact our office if additional information or
services are required.
Respectfully subm
Bob J. Arnold, PE
SITE Consulting, L
208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
H
/LONSU LTI NG, LLC
EXISTING CONDITIONS
Subsurface conditions were similar in all three test pits. The site is covered with a thin
layer of brown, moist, sandy, silt that ranged from 1.0 to 2.0 feet deep. This layer
supports a 4-6 inch organic / rootzone layer. Beneath the topsoil layer is a weakly
cemented silt or sandy silt. At approximately five feet deep, this layer becomes more
sand than silt and is free of cementing. In the west test pit, this deeper layer is
described as sand while in the other two test pits silty sand is appropriate. A thin
hardpan or cemented silt layer was encountered in TP -2 at ten feet deep. This layer
was not observed in the other two test pits. Groundwater was encountered in all three
test pits at 10.5 to 11.0 feet. Monitoring wells were installed in all three test pits for
future groundwater measurements. Below the groundwater, the sand was observed to
be very clean with little to no silt present. Below the groundwater, sloughing soils
prevented deeper excavation with the retained excavation equipment.
The subject property consists of a single parcel located in township 3 north, range 1
west, section 3. Well logs for this and adjacent sections were reviewed on the Idaho
Department of Water Resources website. The nearest well identified is for a property to
the west across Blackcat Road at 3185 Blackcat Road. The attached well log indicates
that the static water level was 12 feet deep when the well was drilled in October 2014.
It is noted that this was right at the end of the typical irrigation season and therefore
should reflect a seasonal high. It is anticipated that groundwater will rise on the subject
property during the irrigation season. Staining (rust) in the sand layer indicates that
groundwater has risen as high as seven feet below the surface.
a,
ba
a
208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
/SITE
ONSULTING, LLC
CONSTRUCTION RECOMMENDATIONS
The following recommendations are based upon observed conditions and reported
laboratory test results.
• Building code allowed bearing capacity of 1500 psf is appropriate for residential
structures to be built on this site. Foundation embedment depth and
reinforcement are to meet local code requirements.
• Every effort is to be made to prevent irrigation / storm water from entering
crawlspaces / basements. This is to include proper waterproofing of foundations,
proper compaction of foundation and basement backfill, and lot grading that
directs runoff away from foundations. Foundation drains are not required for this
development.
• Stripping of organic material will require only minor excavation; 4-6" of grubbing
can be anticipated to completely remove all organic materials from future right of
ways and building pads. This is to be adjusted as needed in the field at the time
of construction. Deeper removal depths should be anticipated near ditches and
where large bushes and trees are present.
• The onsite surface soils are acceptable for use as fill on the residential lots.
• Any subgrade surface to receive structural fill or pavement section materials is to
be watered and compacted as necessary to meet ISPWC compaction
requirements. (95% of maximum dry density as determined by ASTM D-698,
"Standard Proctor). The exposed subgrade surface is also to be proof rolled with
a loaded water truck or ten yard dump truck to confirm that no soft, excessively
wet, or deflecting areas are present. Any such area encountered is to be over
M
excavated as directed by the project geotechnical consultant.
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
ZSITE
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CONSULTING, LLC
• Subgrade surface must pass both visual inspection and compaction testing.
• It should be anticipated that the surface soil will rut or deflect severely if wet
when loaded with rubber tire equipment. Wet or deflecting areas are to be over -
excavated and repaired with structural fill at the time of construction. Subgrade
issues caused by using rubber tire equipment on wet subgrade soils are to be
repaired by and any additional cost borne by the contractor.
• Imported structural fill used to repair over excavations or to elevate the building
pads, support foundations or other concrete, and beneath future pavements
should meet the "Sub Base" specifications of the ISPWC Specifications.
• The cleared, grubbed and approved subgrade and each lift of imported structural
fill is to be compacted to a minimum of 95% of the maximum dry density as
determined by ASTM D698, "Standard Proctor".
• Inplace testing to confirm proper compaction is required. One test each lift,
(minimum of three), for every 5000 square feet of fill surface is recommended.
The project geotechnical engineer can waive subgrade compaction testing based
upon visual inspection at the time of construction.
• For structural fill placed on residential lots, inspection at the time of testing should
confirm that subgrade and structural fill is firm and stable, and free of soft,
excessively wet, or deflecting areas. Subgrade and structural fill can pass
compaction results and still be rejected if rutting or deflection is present.
• Unacceptable soils are to be removed to firm bearing or a maximum depth of 2.0'
and replaced with structural fill. Over excavation of wet or soft areas must
extend laterally outside foundations a distance equal to the depth of fill.
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
ONSULTING, LLC
• Based upon an R -Value result of R=20, it is recommended that ACHD right of
ways consist of the following section. It is noted that SITE uses a maximum
value of R=20 for design of residential streets.
Structural Layer
Thickness
HMA
2.5"
Base Course
4.0"
Sub Base
10.0"
• The following slab on grade floors sections are recommended for inside the
residential structures:
Structural
Layer
Living
Space
Garage
Floors
PCC w/ fiber mesh
4.0"
4.0"
Base Course
4.0"
6.0"
Subgrade
Properly Compacted
and Inspected
• Stormwater disposal can be accomplished with conventional infiltration facilities.
A percolation rate of P = 8 inches / hour is recommended for design of onsite
facilities provided they extend to the free flowing sands encountered in the test
pits at greater than five feet deep. It should be anticipated that ACHD will require
confirmation of percolation rate at the time of construction.
• Testing and engineering inspection services recommended herein are critical for
successful construction of the planned subdivision. Any recommendations
provided by a licensed geotechnical or civil engineer during the construction of
this development, that differ from recommendations herein are to be
communicated to SITE prior to execution.
Appendix Follows
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
SITE
/orLONSULT1NG, LLC
Proposed Plat
Aerial Photo (Test Pit Locations)
Test Pit Logs (3 pages)
Soil Log Legend / Abbreviations and Acronyms
Pavement Section
R -Value Report
Well Log
208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
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AERIAL PHOTO
(Google Earth)
Test Pit Locations by hand held GPS
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
SITE
ONSULTING, LLC
TEST PIT LOG
Test Pit: TP -1
File #:
17118-A
Client: Schultz Development
Date Excavated:
03/17/17
Project: Geddes Property
Excavated By:
Culver Excavation
Location: West End
Logged By:
B. Arnold - SITE
DEPTH
SOILS DESCRIPTION
1.0" 1 3/4" 1 1/2" 1 3/8" 1 #4 #10
#40 #100
#200 1 %M I LL I
PI
0.0-1.0
Brown, Moist, Silty, SAND with 4-6" rootzone
1.0-5.0
Brown, Wet, Sandy, SILT (ML) with cemented layers
(cemented pieces in sieves)
1.5
100 90 87 78
59 46
36.5 28.6 1 NP
NP
4.5
1 100 92 79 76 65
42 32
27.4 29.4 NP
NP
5.0-11.0
Tan to White, Wet to Saturated, SAND
6.0
1 100 1 97 1 87 1 81 68
13 2
1.4 2.7 NP
NP
11.0
Bottom of Test Pit
Groundwater at 10.5'
Sloughing Soils below Groundwater
Monitoring Well Installed... TL=14.33', CH=3.44'
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
SITE
ONSULTING, LLC
TEST PIT LOG
Test Pit: TP -2
File #:
17118-A
Client: Schultz Development
Date Excavated:
03/17/17
Project: Geddes Property
Excavated By:
Culver Excavation
Location: Center, North side
Logged By:
B. Arnold - SITE
DEPTH
SOILS DESCRIPTION
1.0" 3/4" 1/2" 3/8" #4
#10 #40 #100
#200 %M LL PI
0.0-1.0
Brown, Moist, Silty, SAND with 4-6" rootzone
1.0-5.0
Brown, Moist, Cemented, Sandy, SILT (ML)
(cemented pieces in sieves)
R -Value Sampled R=76
100 92
75 60 41
32.2 21.1 NP NP
5.0-10.0
Brown, Moist, Sandy, SILT (ML)
7.5
1 1 1 100
92 87 71
60.0 25.1 NP NP
10.0-10.2
2-3" cemented silt, Hardpan Layer
10.2-11.5
Coarse, Tan to White, Saturated, Silty, SAND
10.5
1 100 1 95 1 90 1 70
55 36 26
20.3 17.8 NP NP
11.5
Bottom of Test Pit
Groundwater at 11.0 -
Sloughing Soils below Groundwater
Monitoring Well Installed... TL=15.09', CH=3.58'
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
ONSULTING, LLC
TEST PIT LOG
Test Pit: TP -3
File #:
17118-A
Client: Schultz Development
Date Excavated:
03/17/17
Project: Geddes Property
Excavated By:
Culver Excavation
Location: East End
Logged By:
B. Arnold - SITE
DEPTH
SOILS DESCRIPTION
1.0" 3/4" 1/2" 3/8" #4
#10 #40 #100
#200 %M LL PI
0.0-2.0
Brown, Moist, Silty, SAND with 4-6" rootzone
2.0-5.0
Brown, Wet, Cemented, Sandy, SILT (ML)
(cemented pieces in sieves)
3.0
100 1 98 1 95
83 50 36
20.7 21.6 NP NP
5.0-11.0
Light Brown to Tan, Moist to Saturated, SAND
11.0
Bottom of Test Pit
Groundwater at 10.5'
Sloughing Soils below Groundwater
Monitoring Well Installed... TL=15.00', CH=3.79'
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
SITE
ONSULT1NG, LLC
SOIL LOG LEGEND
UNIFIED SOIL CLASSIFICATION SYSTEM
(ASTM STANDARD TEST METHOD D 2487 FOR CLASSIFICATION OF SOIL FOR ENGINEERING PURPOSES)
DIVISIONS
American Association of State Highway & Transportation Officials
TYPICAL DESCRIPTIONS
COARSE
GRAINED
SOILS
< 50% - #200
GRAVEL &
GRAVELLY
SOILS
<50% - #4
<5% #200
GW
Well -graded gravel, gravel -sand mixture, little or no fines.
GP
Poorly -graded gravel, gravel sand mixture, little or no fines
5-12%-#200
> 12% - #200
GM Silty gravel, gravel -sand silt mixtures
GC Clayey gravel, gravel -sand -clay mixtures
SAND & SANDY
SOILS
> 50%- # 4
<5% #200
SW Well -graded sand, gravelly sand, little or no fines.
SP Poorly -graded sand, gravelly sand, little or no fines
>12%- #200
SM
SC
Silty sand, sand -silt mixtures
Clayey sand, sand -clay mixtures
FINE
GRAINED
SOILS
SILTS AND CLAYS
LL < 50%
INORGANIC
ML
CL
Inorganic silt and very fine sand, rock flour, silty or clayey fine sand or
clayey silt with slight plasticity
Lean clay -low to medium plasticity, gravelly clay, sandy clay, silty clay
ORGANIC
OL
Organic silt and organic silty clay of low plasticity
SILTS AND CLAYS
LL > 50%
INORGANIC
MH 11
CH
Elastic silt, micaceous or diatomaceous fine sand or silty soil.
Fat clay - high plasticity
ORGANIC
OHI
Organic clay-med. or high plasticity: organic silt 71
ORGANIC SOILS
PT
Peat, humus, swamp soil with high organic content
ABBREVIATIONS AND ACRONYMS
AASHTO
American Association of State Highway & Transportation Officials
ACP
Asphaltic Concrete Pavement
ASTM
American Society for Testing and Materials
BH
Bore Hole
IBC
International Building Code
ISPWC
Idaho Standard for Public Works Construction
ITD
Idaho Transportation Department
NP
Non Plastic
PCC
Portland Cement Concrete
PCF
Pounds per Cubic Foot
PSF
Pounds per Square Foot
TP
Test Pit
USES
Unified Soil Classification System
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
SITE
CONSULTING. LLC
DESIGN SECTION CALCULATIONS
Project: Geddes Property File No.: 17118-A
Geddes @ MoonLake Drive Calc By: B. Arnold
client: Schultz Development Date: 03/27/17
Design Thickness Equation:
T = (0.0384) (TI) (100-R) = GE (inches)
T= Design Thickness TI = Traffic Index = 6 By ACHD
GE = Gravel Equivalent R = R -Value = 20 By Soils Test
GE= 18.4 Inches
ACHD ACP, 3/4" Road Base and Aggregate Subbase
Actual Thickness Equivalent Thickness
ACHD Asphalt Concrete Thickness = 2.5 Inches ACE= 5.0 Inches
3/4" Road Base Thickness Desired = 4.0 Inches RBE= 4.6 Inches
Calculated Aggregate Subbase Thickness Equation:
SB= 9.8 Inches
RECOMMENDED DESIGN SECTION
Asphaltic Concrete = 2.5 inches
3/4" Road Base = 4.0 inches
Aggregate Subbase = 10.0 inches
SITE Recommends maximum R -Value of R=20 for Subdivisions
208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
/'SITE
ONSULTING. LLC
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RESISTANCE (R) VALUE TES
ASTM D 2844
Laboratory No.-
L170240
Project No.:
170023
Sample Date:
NIA
Report Date:
April 5, 2017
Client
Site Consulting LLC
Project Name.
2017 Laboratory Testing
Sample Description* Brown Silty San
Sample Location! Geddes
800 700 600 500 400 300 200 100 0
'Exudation Pressure (RS.1.)
—Resistance Value Test —300 P.
100
90
80
70
60
50
40
30
20
10
0
Specimen No.
4
6
Moisture Content
21.4
-5
20.0
19.3
Dry Density (PCF)
99,0
99.0
98.7
Resistance Value (R)
72
77
80
Exudation Pressure (PSI)
160
336
557
,Expansion Pressure
4
30
35
JAs Received Moisture Content
21.4
A
Ktblb IANL;h VALUL Al MU fb
Reviewed
By: Brandon Rodobaugh
AN
Materials Engineer
WELL LOGS
208-440-6276 bjarnoldpe@msn.com Post Office Box 190537 Boise, Idaho 83719
SITE
/CONSULTING, LLC
Fem 23,0-7
&07 IDAHO DEPARTMENT OF WATER RESOURCES
WELL DRILLER'S REPORT
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208-440-6276 bjarnoldpe@msn.com Post Office Box 190537 Boise, Idaho 83719
Mr. Matt Schultz June 7, 2017
Schultz Development Page 1 of 2
Post Office Box 1115 File # 17118_B
Meridian, Idaho 83680
Re: Geotechnical Report Addendum #1
Geddes Property
East of 3050 North Blackcat Road
Meridian, Idaho
Matt:
As per you request, SITE has measured the groundwater elevation monthly in the three
wells we installed in March 2017 on the referenced property. We will continue with
month measurements through the end of this irrigation season. Groundwater elevations
to date are listed in the table below.
Location
TP -1
TP -2
TP -3
Casing Height
3.44
3.58
3.79
Hub Elevation
2549.18
2550.28
2550.24
Casing Elevation
2552.62
2553.86
2554.03
311712017
Date Excavated
10.50
2542.12
11.00
2542.86
10.50
2543.53
4/28/2017
Water Elevation
12.15
2540.47
12.44
2541.42
12.51
2541.52
5/30/2017
Water Elevation
10.70
2541.92
10.52
2543.34
10.66
2543.37
Water Elevation
Water Elevation
Highest Measured
Groundwater
2542.12 1
2543.34
2543.53
We appreciate this opportunity to be of service. Please contact our office if additional
information or services are re uired.
AL
Respectfully
Respectfully submi
Bob J. Arnold, PE
SITE Consulting, L
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208-440-6276 * bjarnoldpe@msn.com * Post Office Box 190537 * Boise, Idaho 83719
ONSULTING, LLC
Aerial Photo
Monitoring Well Location
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