HomeMy WebLinkAboutPrimary Health Meridian - Hydrological Assessment Report (2)Primary Health
Meridian
City of Meridian,
Ada County, Idaho
HYDROLOGICAL
ASSESSMENT REPORT
9-12-2013
Prepared For:
Rocky Mountain Development
Boise, ID
Prepared By:
FNGINtERS
SURVEYORS
PLANNERS
3023 Copper Point Dr. #201
Meridian, ID 83642
Scott Sherrow, PE
Date:
September 10, 2013
Primary Health Meridian
Hydrological Assessment Report
Primary Health Meridian
INTRODUCTION...................................................................................................................................1
GENERAL PROJECT DESCRIPTION...............................................................................................1
PROJECT DESIGN CONCEPTS........................................................................................................1
HYDRAULIC ASSUMPTIONS: .................... ___ .... __ ................... ..................................................... I
Table 1 — Basin Characteristics Summary .........................................................................2
Table 2 — Stormwater Summary ............................................................................................2
STORMWATERFACILITIES.............................................................................................................3
SEEPAGEBED..........................................................................................................................3
Table 3 — Seepage Bed Summary.........................................................................................3
II. Tab 1: Drawing Documents
Post Development Drainage Maps
Grading & Drainage Plan
III. Tab 2: Calculations, Spreadsheets and Computer Model Output
DB1- Seepage Bed — Volume and Flow
Sand/Grease Trap Calculations
IV. Tab 3: Engineering Support Documentation
Strata's Geotechnical Report—August 21, 2006
Project No. 13-3023—Primary Health—Meridian- Hydrological Assessment Report
LEI • 3023 Copper Point Dr. • Meridian, ID 83642 • P: 208.846.9600
ENGINEERS
SURVEYORS
Pt AN N E RS
I. Primary Health Meridian
INTRODUCTION
The Primary Health Meridian project is situated within the City of Meridian, Ada County, being located in
the northeast corner of the intersection of E. Overland Road and S. Wells Avenue. The Rockery
Mountain Development is proposing to develop a +-5,600 sf building on approximately 0.73 acres.
The purpose of this report is to determine the hydrologic impacts that the proposed development may
have on the existing runoff patterns and flow characteristic from the site.
This hydrological assessment was completed after review of the following information: The past
development plans, topographic and boundary map information; historical storm data (Ada County);
available SCS soil maps; and the Geotechnical Engineering Report prepared by Strata, Inc. This data
was then analyzed with the Rational Method utilizing a computer modeling spreadsheet for the drainage
basins. This program provides information on storm runoff volumes, peak rate of discharge, and storage
design storage volume requirements. Design recommendations are based on the results of the analysis.
GENERAL PROJECT DESCRIPTION
The site is bounded on the north by E. Overland Road, to the south and west by undeveloped plated lots
and to the east by S. Wells Avenue. Ground cover consists of bare dirt to light field grasses.
PROJECT DESIGN CONCEPTS
Storm water runoff from the portions of the building roof surface and hard scape areas will be conveyed to
an oil & sand separator and to the proposed infiltration facilities. Portion of the roof system and
landscape areas not subject to vehicular traffic will be conveyed to depressed areas within the
landscaped areas. For additional information on the drainage basin locations and limits, refer to the
drainage basin maps located in Tab 1 of this report.
On-site storm water improvements for the project will consist of curb and gutters, catch basins, manholes,
stormwater conveyance pipelines, sand/grease traps (pretreatment water quality structure) and the
infiltration facilities. Stormwater utility improvements provided for the project will be in accordance with
ACHD's Storm Water Management Manual, and per ACHD's storm water management policies as
amended by the City of Meridian. The infiltration facilities will consist of underground seepage beds.
For the purpose of hydrological analysis and for computer modeling of Primary Health Meridian project,
the following basin conditions were modeled utilizing the Excel Spreadsheet published by ACHD Dated
April 14, 2013,
Seepage Beds4 Post -Development runoff Volume (100 yr storm event), to determine
storage and infiltration requirements and to determine conveyance system
sizing requirements, Rational Method Runoff.
HYDRAULIC ASSUMPTIONS:
Project No. 13-3023—Primary Health—Meridian- Hydrological Assessment Report
LEI • 3023 Copper Point Dr. • Meridian, ID 83642 • P: 208.846.9600
ENGINEERS
SURVEYORS
PLANNERS
LEI utilized the following assumptions in establishing the post -development stormwater runoff conditions
for the proposed Primary Health Meridian project hydrological assessment/report:
Runoff Evaluation Method: A spreadsheet program based on the Rational Method was utilized.
The following Items were reviewed:
• Established values from the Intensity -Duration -Frequency Curve Chart for "Zone A" from
the ACHD's Storm Water Management Manual
• The 100 -yr storm event with 60 minute duration was evaluated to determine the
developed runoff volume.
• Existing site conditions
• Drainage patterns
Runoff Coefficient "C": Per Section 8130.2 ACHD's Storm Water Management Manual, C
values were chosen. C = 0.95, which represents the asphalt paving was used and a value of C =
0.2, which represents landscape areas.
Rainfall Intensity "I": I values, are determined from the Intensity -Duration -Frequency's listed in
Section 8130.2 ACHD's Storm Water Management Manual.
Time to Concentration "Tc": Tc values are calculated for each basin using the FAA Method (Used
by City of Boise). This method analyzes the combination of sheet flow, shallow concentrated
flow, and channel flow characteristics associated for each drainage basin to arrive at an overall
time which represents the length of time required for a particle of water to flow hydraulically from
the most distant point in the watershed to the outlet or design point. The minimum value of 10
minutes was used in the analysis.
POST DEVELOPMENT CONDITIONS
Computer modeling of the design storm for the post -development condition of the Primary Health
Meridian project utilizing the Rational Method produced the following results, see Table 1&2:
I axle I — oasm L naractensTlcs aummar
Basin Area
Acres
Impervious
Acres
Pervious
Acres
Avg. Runoff
Coeff.
D131 0.43
0.353
0.077
0.82
DB2 0.19
0.064
0.13
0.45
See computer spreadsheets Tab 2 for details.
rauroa—vwnnvraacl vuuuuary
Basin Storm Event Flow Rate Storage Time of
(Q100) Volume req.* Conc.
DB1 100 yr 1.10 1,461 10.00
DB2 100 yr 0.28 401 10.00
`See computer spreadsheets Tab 2 for details.
Page 2 Project No. 13-3023 — Primary Health — Meridian - Hydrological Assessment Report
LEI: •3023 Copper Point Dr. - Meridian, ID 83642 • P: 208.846.9600
[NGI4Et RS
SURVEYeRS
PLANNERS
STORMWATER FACILITIES
The stormwater disposal systems are designed to contain the 100 -year storm event. The location and
parameters of the seepage bed facilities have been detailed in the construction plans for which all sheets
relating to the storm water seepage beds have been included in the Tab 1 of this report.
Storm water from surface runoff and the building will ultimately be conveyed either to the infiltration
facilities or retained on site within the landscape areas.
The storm water infiltration facilities will be configured in accordance with the general guidelines
published by ACHD associated with storm water treatment/retention/infiltration and in accordance with
ACHD's storm water management policies as amended by the City of Meridian.
A typical sand/oil trap has been designed into the stormwater system to provide water quality treatment of
the flowrate of run-off associated with the 100 yr storm event before discharging into infiltration basins.
Secondary water quality treatment is provided by maintaining a three foot separation between the bottom
of pond and the seasonal high ground water elevation.
SEEPAGE BED
The seepage beds for the Primary Health Meridian project have been designed to fully contain the 100 -
year storm event. For the design of seepage beds, Strata's Geotechnical Report dated August 21, 2006
was referenced to determine soil characteristics & infiltration rates to size the seepage beds and to
determine depth to bedrock.
Using the data from the computer modeling spreadsheet and geotechinicl reports recommended
infiltration rates; the required storage volume for the seepage bed was determined. A void space (e) of
40% was assumed and used to size the seepage beds. The Table 3 summarizes seepage beds sizing
results.
Table 3 — Seepage Bed Summary
Seepage Width
Length
Depth
Infiltration
Actual
Bed
Rate
Storage'
ft.
ft:
ft.
in/hr)
(cu.f
DB1 15
40
6
8
1,448
Length x Width x Depth x e
Page 3 Project No. 13-3023 — Primary Health — Meridian - Hydrological Assessment Report
LEI: •3023 Copper Point Dr. • Meridian, ID 83642 • P: 208.846.9600
TAB 1
DRAWING DOCUMENTS
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CALCULATIONS
SPREADSHEETS
COMPUTER MODEL OUTPUT
9/4/2013
Project Primary Health
Basin Data
Basin ID Area Pervious Impervious CN Ave Tc Min 125yr Q25 CFS 1 100 yr in/hr Q700 CFS
Acres CN=0.20 CN=0.95 I in/hr
DB1 0.43 0.077 0.353 0.82 10 2.37 0.83 3.11 1.09
DB2 0.194 0.13 0.064 0.45 10 2.37 0.21 3.11 0.27
Rational Method
Q = C*I*A
C = 0.9 (Runoff Coefficient forthe Rational Method)
A = 0.86 acres (contributing area)
I = #N/A in/hr(Rainfall Intensityforthe Design Storm Duration;
Design Storm
Tc ___________________________________-------------
2
5
Boise Area Intensity -Duration -Frequency
Intensity (inches per hour)
10 25 30 50
________________
100
0.17
10 min
1.21
1.67
1.96
2.37
2.44
2.73
3.11
0.25
15 min
1.02
1.41
1.66
2.00
2.06
2.30
2.62
0.33
20 min
0.85
1.17
1.37
1.67
1.72
1.91
2.28
0.42
25 min
0.74
1.01
1.19
1.44
1.48
1.65
2.02
0.50
30 min
0.71
0.98
1.15
1.39
1.43
1.59
1.82
0.58
35 min
0.59
0.81
0.95
1.14
1.18
1.31
1.50
0.67
40 min
0.54
0,74
0.87
1.05
1.08
1.20
1.37
0.75
45 min
0.50
0.68
0.81
0.97
1.00
1.11
1.26
0.83
50 min
0.47
0.64
0.75
0.90
0.93
1.04
1.17
0.92
55 min
0.45
0.62
0.73
0.88
0.90
1.01
1.15
1.00
1 hour
0.45
0.62
0.73
0.88
0.90
1.01
1.15
2.00
2 hours
0.27
0.36
0.42
0.50
0.52
0.58
0.66
3.00
3 hours
0.20
0.27
0.32
0.37
0.38
0.43
0.48
6.00
6 hours
0.13
0,17
0.20
0.23
0.24
0.27
0.30
12.00
12 hours
0.08
0.11
0.13
0.15
0.16
0.18
0.19
24.00
24 hours
0.05
0.07
0.08
0.09
0.10
0.11
0.12
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.
User input in yellow cells. To accept default value type- in yellow cell and point to
1 Project Name Primary Health -Meridian Parking & Building
2 Is area drainage basin map provided? yes
(map must be included with stormwater calculations)
3 Enter Design Storm For Volume (100 -year per ACHD policy) I00
4 Enter number of storage facilities (25 max)
5 Area of Drainage Sublesin (SF or Acres) Acres
Acre
6 Determine the Weighted Runoff Coefficient (C)
C=((CIKA1)+(C2xp2)+(CnxAn)]/A. Weighted Avl
Clickto Show Moie Subuiaas 11
Subbasin
1.10
5ubbasin
Subbasln
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin 2
3
4
5
6
]
8
9
10
0.43
Enter W0 Volume (Vvru= Cyr Ili am lm a above) xAx1600) Vin,
432
ft'
13 D111chon Approvei Dtsvha pe Pate to Sunoco Waters (If applicable)
oafs
0.43
0.82
0.82
Calculate Overland Flow Tme of Concentration in Minutes (Tc) or use default user cawlate A
10 min [lh "1, I
V
^ Calculate me Port-Proletl peak discharge (QPevi u.,•
1.10
Rs
m Calculate Peak Civv9 (uses 2" storm) Com�0
i�
d eUd
SieXlc(am{x
ra,unf.r.ax
(used for S/G Tap threat valued , WQstmn conveyance rystem Bain, j
Resdemam rrw>!k
05-0.44)
II Csl,u late Iota l runoff v.I(V)(far sizing pitman, storages V
1,461
f[
V = C, (Trz61
parks-cewraoaln
aS0-025
12 Calculate Vwq (for s Ing WO facilal es)
6121-035
nxllryyd sand.
Enter Fell 'I ti I e Storm I(80th pe rc,,i=034 in)
80th
0.34 In
Enter W0 Volume (Vvru= Cyr Ili am lm a above) xAx1600) Vin,
432
ft'
13 D111chon Approvei Dtsvha pe Pate to Sunoco Waters (If applicable)
oafs
ev0 Plnnd corehaq _ 1117111,1: 496 it,
1,029
-
_ c. 1.461 tl
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6121-035
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vn,,ao,ed.
oto -ono
soarers
9/11/2013, 11:42 AM
\\Leistomge\common\Projects\Rocky Mountain Development\Primary Health McGdiam Ui ;APFYid@APnmary Health- Parking & Building ACHD Method SD Cals 2013-9.5 SAS
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 methadmlogy most result
in Facilities that meet or exceed these calculations in order to be accepted.
Note this spreadsheet pulls information from the "Peak Cbv" tab
Calculate Post -Project Flows (for pre -project flows, increase number of storage facilities to create new tab)
User input in yellow cells. To accept default value type= in yellow all and point to computed cell
1 Project Name Primary Health- Meridian Parking & Building
2 Enter number of 5eepage Beds (25 max)
B Design Stolrn
V ,fay,:..
C Welgbted BunoH C.01cAnl c
u
B F'
5 Area A IA6res)
Gx
LSb If
6Approved drsaharge rare for tl¢ gl,cu storm
if nuCalle)
O.BO r1�
2 Design VPI W/B5%Sal in, Per, , B In/hf
V
4VEI
0%Sxdiment for Per, W Ii
8$a t T' or l Occm Wldlh of All Drain Rock
W
15.01,
9 Ser Total Design Depth of All Drain Rad
D
60 ft
Rock only. Dm Nol Include Pllte Sand Depth
m' fi'mel
10 Void Ratio of Dra1n Rork
VouB
CA
UA for 1.5"-1" drain rock and 3(4"Chlps
star,
I l Design Infiltration Rate IS III/hr mah)
peo,
B In/hr
12 Area lnfiltratlon
Apert
CBS It
13 Volmne lonidaflon
Vpem
404 ft'/h,
14 Stu of or( Dr. ➢la Pipv IS In
15 CSNnIata Total Storage Pal Foal
5Pf=Apf"WAD A,., ,,xVo1d511/2Peitglen
I
_-.. �.-.Ili, Period
tinN ro: �pvl� rt55�^
I
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19 Total Length W Iwd Pipa
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40
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9/11/2013,11:44 AM
\\Leisiorage\common\PraJeRs\Pocky Mountain DevelopmentrPdm3ry Health Meridian\Sto,t,Or fnnw,WAm rpQ0 kR1th - Parking & Building ACHD Method SD Cals 2013-9-S 3A5
ACHD Calculation Sheet for Sand/Grease Traps
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 Sand/Grease Trap Velocity Calculation
User input in yellow cells. To accept default value type = in yellow cell and point to computed cel
1 Project Name Primary Health - Meridian Parking & Building
[Hier npmper UT>ana/urease (raps 10 maxi 1
reference for Throat widths (inch)
Baffle
Throat
Boise
VeIn ty
the
Vault Size
Number of
Peak Flow
Spacing
width
Area (ftz)
0.5 fps
el
Vel
1000 G
S/G Traps
Q -ds
inch
inch
60.0
max.
ok?
1000 G
I 1
1.1
19
48
6.33
0.17
60
reference for Throat widths (inch)
\\Leistorage\common\Projects\Rocky Mountain Development\Primary Health Meridian\Storm Drainage\Primary HEWn/-2Rir%idA&4 AM
Building ACHD Method SD Cals 2013-9-5 SAS Version 5.5, April 2013
ADS
Boise
Vault
Lar -ken
WQU,
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1000 G
48.0
50.5
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1500 G
60.0
61.5
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n/a
n/a
60
NQU1500
n/a
n/a
60
\\Leistorage\common\Projects\Rocky Mountain Development\Primary Health Meridian\Storm Drainage\Primary HEWn/-2Rir%idA&4 AM
Building ACHD Method SD Cals 2013-9-5 SAS Version 5.5, April 2013
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 t0 be accepted.
Steps for Peak Discharge Rate wring the Rational Method caieulated for post bojau
Calculate Post -Project Flows (far pre -project flows, increase number of storage facilities to create new tab)
User input in yellow cells. To accept default value type = in yellow cell and point to computed cell
1 Project Name Primary Health - Meridian - Building&Landscape
2 is area drainage basin map provided? Yes
(mop must be included with stormwater calculations)
3 Enter Design Storm For Volume (100 -year per ACHD policy) 100
4 Enter number ofstorage facilities (25 max)
5 Area of Drainage Subbasin (SF or Acres) Acres
Acre
6 Determine the Weighted Runoff Coefficient (C)
C=((C1xA1)+(C2xA )+(CnxArd]/A Weighted Asti
F1
Subbasin
a.0 nvn
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
Subbasin
1
Subbasin2
3
4
5
6
]
8
9
10
0.19
VJFT c 8'1'
saee4
0.19
0.45
0.45
]Calculate Overland Flow Time of Concentration in Minutes(Tc) or use default !k_ cxsxaie A
10 min mAitr.—�
V
nage Sanwa nmeou, r9., nm 'm an
a.0 nvn
9 Calculate the Post-Pfo]ect peak bsclerge(OPeakl 0,111
024 cfs
to Cakuiate Peak Caul fuses 2y strai 4..
0.10 Os
(used for SAG Tay tivoat aloofly. WOsterm conveyance system sizing ]
4s5-aS2
461.Ti
11 Calculate total runoff.. V)Ifor Shing primary swrage) V
354 IL'
V = Ci (rc=60)Ax36(10
a]ff
I 2 Calculate Vwq (for suing WO f idi tles)
295
Enter Pereenttle Storm I (BOB, percentile=0.34 m)
00th 0.34 m
Fater WO Velum, V,L"- Cxi(from bne above)xA.3600) V111
105 ft
.� Detention: Approved Discharge Pate to SUHace Waters (if applicable)
cis
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- 3S4 Il
9/11/2013,12:29 PM
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9/11/2013,12:29 PM
\\Leist... ge\common\Pmjects\Rocky Mountain Development\Primary Health MCMdie atS 5abiri "arfigorPrimary Health - Landscape & Building ACHD Method SD Cals 2013-9-5 SAS
ACHD Calculation Sheet for Sizing Ponds
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 faciligeethat meet
or exceed these rahulatmm In order to be accepted.
User Input M yellow cells. To accept defauh value type= in yellow cell and point to computed sell
I Pralect Name Primary Heahh-Meridian- Building& Wndempe
um. re nrlV=S.I t
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GEOTECHNICAL
REPORT
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Mr. Taylor Merrill
The West Park Company, Inc.
P.O. Box 344
Meridian, ID 83642
Dear Mr. Merrill:
August 21, 2006
File: WESTCO B06186A
RE LETTER REPORT
Preliminary Geotechnical Evaluation
Proposed Commercial Development
Overland Road and Eagle Road
Meridian, Idaho
STRATA, Inc. is pleased to present our authorized preliminary geotechnical
evaluation for the proposed commercial development on an approximate 80 -acre property
located south and west of the intersection of Overland Road and Eagle Road in Meridian,
Idaho. The purpose of our services was to provide you with the preliminary information that
may assist your planning and conceptual design efforts for the overall development.
Additionally, STRATA has performed an evaluation of near -surface soils in the northern
portion of the site with respect to placement of structural fill, and support of lightly loaded
commercial structures in this area. Our services were performed referencing our confirming
proposal dated August 7, 2006.
PROJECT UNDERSTANDING
We understand you plan to develop an approximate 80 -acre parcel for future retail
and commercial development, as well as residential development. Commercial and retail
development is anticipated to be located in the northern and central portions of the site, with
residential development proposed in the southern portion. The site will be accessed from
Overland Road to the north and by local streets to the east and west.
FIELD EXPLORATION AND LABORATORY TESTING
On August 9, 2006, STRATA observed the excavation of 11 test pits across the
subject property. Test pit locations are presented on Plate 1, Site Plan and were
approximately located in the field relative to existing site features. Test pit locations were
not surveyed, but were labeled and staked in the field, so the locations may be documented
at a later time period. Test pits were loosely backfilled roughly level with the ground surface
at the completion of our field investigation. We recommend all test pit backfill be re -
excavated to sufficient depth to expose native soil, and replaced with structural fill. This will
heap to reduce the potential for localized test pit backfill settlement.
The soils encountered within the test pits were described and classified referencing
ASTM D 2487 and ASTM D 2488, Unified Soil Classificat€on System (USCS). The test pit
logs and a brief explanation of the USCS are presented in the Appendix Select soil
wwwstratageote<h.cn m
Proposed Commercial Developmern
Overland Road and Eagle Road
File: WESTCO B06186A
Paget
samples were obtained for index laboratory testing. Index laboratory test results are
presented on individual test pit logs.
Subsurface Conditions
Soils encountered within the test pits generally consist of lean clay at or near ground
surface, overlying variably cemented clayey sand, silty sand, and silt grading to poorly -
graded gravel or silty gravel with depth- Lean clay was typically observed at ground surface
in all test pits, and was generally described as brown to dark brown. very stiff to hard and
slightly moist to moist. Clay soils were observed to extend to depths of approximately 0.5 to
as deep as 4 feet below ground surface with the depth of clay typically increasing from north
to south.
Underlying near -surface clay, light brown to reddish -brown, very stiff to hard, sandy
silt, dense to very dense silty and clayey sand was observed. Calcium -carbonate
cementation was observed throughout these soils to varying degrees, with these soils
extending to depths of 2 to 4 feet in the northern portion of the site and to depths of 4.5 to in
excess of 10 feet for the remainder of the site. Poorly -graded gravel and/or silty gravel with
sand was typically encountered in test pits underlying cemented soils. The depth to silty
gravel and poorly -graded gravel was observed to vary significantly with gravel typically
present at depths of 2 to 6 feet in the northern portion of the site, becoming deeper in the
southern portion of the site with gravel not encountered within the exploration depths in
some locations.
Groundwater was not encountered within the depths explored during this
investigation. Groundwater levels in the site vicinity are related to agricultural and
commercial irrigation as well as canal leakage in the general area. Based on our
knowledge of the site, observed subsurface conditions, and review of topographic
information, we anticipate that groundwater will remain at depths of greater than
approximately 15 to 20 feet below ground surface throughout the year. However, note that
groundwater levels may vary with seasonal changes in irrigation, precipitation, infiltration,
and development to the project site. These groundwater depths are only an estimate and
some seasonal and yearly fluctuation may be observed.
PRELIMINARY GEOTECHNICAL OPINIONS AND RECOMMENDATIONS
It is our preliminary opinion the site is suitable, from a geotechnical standpoint, for
future commercial development and associated infrastructure provided the recommendations
outlined in this letter and future evaluation for the site development plan are accomplished.
The findings contained herein reflect our understanding of the project concepts and subsurface
conditions encountered during exploration- The opinions provided herein should be used only
for planning and not final design STRATA can provide final geotechnical recommendations
relative to foundation and slab pavement design, site grading and drainage, and subsurface
stormwater disposal as the design of the project develops.
www.stratageatech.com -