CC - Storm Drainage Calcs STORMWATER RUNOFF CALCULATIONS
for
GODDARD CREEK SUBDIVISION
Meridian, Idaho
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LEAVITT & ASSOCIATES
ENGINEERS, INC.
1324 11 Street South,Nampa Idaho 83651 —(208)463-7670—www.leavittnengineers.com
Revision# Prepared and Certified by I Reviewed by I Project#
0 Nathan J. Porter, P.E. I Dan Lardie SD078.001
DESIGN CRITERIA:
City of Nampa— Stormwater Policy Manual
100-year Design Storm Frequency for Storage Facilities
50-year Design Storm Frequency for Primary Conveyance Systems
100-year Storm Frequency for Secondary Conveyance Systems
TABLE OF CONTENTS
RunoffArea Map---------------------------------------------------------------------------------------------- 1
Predevelopment Flow----------------------------------------------------------------------------------------- 2
RunoffAreas--------------------------------------------------------------------------------------------------- 3
Methods--------------------------------------------------------------------------------------------------------- 6
Area 1 Post Development Flow----------------------------------------------------------------------------- 7
Area1 Facility Sizing----------------------------------------------------------------------------------------- 8
Area 2 Post Development Flow----------------------------------------------------------------------------- 9
Area2 Facility Sizing----------------------------------------------------------------------------------------10
Area 3 Post Development Flow----------------------------------------------------------------------------I I
Area 3 Facility Sizing----------------------------------------------------------------------------------------12
Area 4 Post Development Flow----------------------------------------------------------------------------13
Area 4 Facility Sizing----------------------------------------------------------------------------------------14
Area 5 Post Development Flow----------------------------------------------------------------------------15
Area 5 Facility Sizing----------------------------------------------------------------------------------------16
PipeFlows-----------------------------------------------------------------------------------------------------17
Sand& Grease Trap Design--------------------------------------------------------------------------------18
Conveyance ---------------------------------------------------------------------------------------------------19
GrateInlets----------------------------------------------------------------------------------------------------20
FEBRUARY11,2021
i
DRAINAGE AREA 3
TOTAL: 22,492 SQFT.
PAVEMENT: 8,392 SQFT.
ROOF: 6,272 SQFi.
LANDSCAPE: 7,828 SQFT.
DRAINAGE AREA 4
DRAINAGE AREA 5 TOTAL: 14,058 SQFT.
TOTAL: 11,949 SQFT. PAVEMENT: 3,989 SQFT.
PAVEMENT: 2,238 SQFT. ROOF: 3,136 SQFT.
ROOF: 3,136 SQFT. LANDSCAPE: 6,933 SQFT.
LANDSCAPE: 6,575 SQFT.
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s
DRAINAGE AREA 2 DRAINAGE AREA 1
6 TOTAL: 76,865 SOFT. TOTAL: 76,491 SQFT.
E PAVEMENT: 19,090 SQFT. PAVEMENT: 17,833 SQFT.
ROOF: 21,952 SQFT. ROOF: 18,816 SQFT.
3 LANDSCAPE: 35,823 SQFT. LANDSCAPE: 39,842 SQFT.
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.We: LEAVITT&ASSOCIATES
DRAINAGE AREA MAP ENGINEERS, INC.
H STRUCTURAL*CIVIL
2 wne�SI CONSTRUCTION Project GODDARD CREEK SUBDIVISION SURVEYING
N
1016 W.SANETTA ob Number;
$ NAMPA,IDAHO83651 SD078.001 1"=100'
PHONE:(208)283-7427 esiene y:DL raven y: ec,e y:NJP 1324 FlRSI STREET SOVIH, NAMPA IDAHO 83651 BC
r PFgNE(208)463-M/463-7670 FAX (208H63-9040
PAGE
LEAVITT& ASSOCIATES ENGINEERS, INC. JOB: Mitera
1324 1st Street South JOBNUMBER: SD086.001
Nampa,Idaho 83651 DATE: 2/11/2021
(208)463-0333 FILE:
Design Criteria
Subdivision Information
Total Area: 201855 sf= 4.63 acres
Type of Area: Urban Construction Type: Residential-Single Family
Average Slope: 1%
Policy Manual:ACHD Policy Manual-Section 8000.Drainage-2015
Rainfall Intesity Area Classification: Zone A
Primary Conveyance Design Storrs Frequency: 25 yr
Secondary Conveyance Design Storm Frequency: 100 yr
Minimum Depth of Freeboard: 6 in (18 in preferred)
Maximum Side Slope of Infiltration Swales 3:1
Minimum Depth of Bottom of Infiltration Facility to Groundwater. 3 it
Minimum Depth of Bottom of Infiltration Facility to Bedrock: 3 ft
Time of Infiltration Until No Visible Water Exists After Primary Storm: 48 him
Time of Infiltration Until No Visible Water Exists After Secondary Storm: 72 him
Predevelopment Flow
2 25 50 100
C= 0.13 Isom„ (inthr) 0.26 0.69 0.82 0.96
(INhr) 0.04 0.08 0.0E 0,10
Qu= CiA Qu somti (cfs) 0I 0 442 0.49 0.58
Qua4K1(cfs) 0,03 0.05 0.05 0.06
Storm Conveyance Statement
The primary flow will be conveyed through gutters,sand&grease traps,catch basins,drop inlets&grates,
and pipes with minimum impact or inconvenience to the public.
The following items will be designed based an the primary flow:
-sand&grease traps -pipes
-catch basins -gutters(clear driving lane)
-drop inlets&grates
The secondary flow:
-gutters(depth of water does not exceed 12 in.)
PAGE 3
LEAVITT&ASSOCIATES ENGINEERS, INC. JOB: Imitera
1324 1st Street South JOB NUMBER: SDO86.O01
Nampa,Idaho 83651 DATE: 2/11/2021
(208)463-0333 FILE: 0
Runoff Areas 8 Runoff Coefficients
Cd= Developed runoff coefficient = 0.50 (or use Cmo.m value if higher)
Cmua m
Roof Area(0.95)+Paved Area(0.90)+Landscaped Area(0.20)+Gravel Area(0.4)+Undeveloped Area(0.15)
=
Total Area
Tc= Time of Concentration,based on Kirpichs equation for flow on concrete or asphalt
Lis
Tc=0.0078 x( has )On
L=Length of roadway from furthest point to drainage facility,(ft)
h=elevation change from furthest point to top of drainage facility(ft)
` if Tc>1 hr,use 60 min
Area 1 (9 lots) ft, acres
Total Area= 76,491 1.76
Total Hardsurface(ROW+500 sq ft 17,833 0.41
driveway per lot)=
Roof Area= 18.816 0.43
Total Landscape 39,842 0.91
Landscape Runoff(67%of Total 26,694 0.61
Landscape)=
Length of Drainage Path,L(ft)= 150
Elevation Change,h(ft)= 1.0
Effective Area=Hardsurface+Roof+
67%Landscape 63343 1.45
Cma4Med= 0.55 Use 0.55
Tc(min)= 3 min Use 10
Area 2 (10 lots) ft acres
Total Area= 76,865 1.76
Total Hardsurface(ROW+500 sq ft 19,090 0.44
driveway per lot)=
Roof Area= 21,952 0.50
Total Landscape 35,823 0.82
Landscape Runoff(67%of Total 24,001 0.55
Landscape)_
Length of Drainage Path,L(ft)= 150
Elevation Change,h(ft)= 1.0
Effective Area=Hardsurface+Roof+
67%Landscape 65043 1.49
Cmpar�= 0.59 Use 0.59
To(min)= 3 min Use 10
NOTE:
Rainfall on individual lots is the responsibility of the homeowner. However,the stonnwater shall accommodate flows from the
driveways and half of the area of the homes and garages in the subdivision. As a conservative measure,67%of all landscaped
areas,which includes private properties and the remaining half of the roof area,has been considered to contribute to the public
stormwater system.
PAGE
LEAVITT&ASSOCIATES ENGINEERS, INC. JOB: Mitera
1324 1st Street South JOB NUMBER: SD066.001
Nampa,Idaho 83651 DATE: 2/11/2021
(208)463-0333 FILE: 0
Runoff Areas&Runoff Coefficients
Area 3 (4 lots) ft2 acres
Total Area= 22,492 0.52
Total Hardsurface(ROW+500 sq It 8,392 0.19
driveway per lot)=
Roof Area= 6,272 0.14
Total Landscape 7,828 0.18
Landscape Runoff(67%of Total 5,245 0.12
Landscape)=
Length of Drainage Path,L(ft)= 100
Elevation Change,h(ft)= 0.5
Effective Area=Hardsurface+Roof+
67%Landsca 19909 0.46
Cma ffie = 0.671 Use 0.67
Tc(min)= 2 min Use 10
Area 4 (2 lots) ft" acres
Total Area 14,058 0.32
Total Hardsurface(ROW+500 sq ft 3,989 0.09
driveway per lot)=
Roof Area= 3,136 0.07
Total Landscape 6,933 0.16
Landscape Runoff(67%of Total 4,645 0.11
Landscape)=
Length of Drainage Path,L(ft)= 100
Elevation Change,h(it)= 0.5
Effective Area=Hardsurface+Roof+
67%Landscape 11770 0.27
Cmodified= 0.57 Use 0.57
To(min)= 2 min Use 10
NOTE:
Rainfall on individual lots is the responsibility of the homeowner. However,the stormwater shall accommodate flows from the
driveways and half of the area of the homes and garages in the subdivision. As a conservative measure,67%of all landscaped
areas,which includes private properties and the remaining half of the roof area,has been considered to contribute to the public
stormwater system.
PAGE
LEAVITT&ASSOCIATES ENGINEERS, INC. JOB: Mitera
1324 1st Street South JOB NUMBER: SDO86021
Nampa,Idaho 83651 DATE: 211 112 62 1
(208)463-0333 FILE: 0
Runoff Areas&Runoff Coefficients
Area 5 (2 lots) ftz acres
Total Area 11,949 0.27
Total Hardsurface(ROW+500 sq ft 2,238 0.05
driveway per lot)=
Roof Area= 3,136 0.07
Total Landscape 6,575 0.15
Landscape Hunoff(61%of I otal 4,405 0.10
Landsca e =
Length of Drainage Path,L(it)= 100
Elevation Change,h(ft)= 0.5
Effective Area=Hardsurface+Roof+
67%Landscape 9779 0.22
CmoMed= 0.531 Use 0.53
To(min)= 2 mini Use 10
NOTE:
Rainfall on individual lots is the responsibility of the homeowner. However,the stonnwater shall accommodate flows from the
driveways and half of the area of the homes and garages in the subdivision. As a conservative measure,67%of all landscaped
areas,which includes private properties and the remaining half of the roof area,has been considered to contribute to the public
stormwater system.
PAGE
LFJIN"S.ASSOC/AYES F INS S.INC. JOB: Miters
1324 liu Street South .IdauuMeOt SD088.001
Nampa,Idaho 83651 DATE: ZI11I2021
20814 0333 FILE: 1 0
STORM RUNOFF CALCULATIONS-RATIONAL METHOD
SUMMARY OF RATIONAL METHOD
FLOWCALCULATION Table l:Zone A Ralnfal intensity, I final
Duration 2 25 so IN
10 0.69 1.85 2.20 2.68
Gp RUNOFF FLOW,CPS=C-i'A 15 0.59 1.56 1.86 Z18
i=Ralnfal Intensity-From Table 1:Zane Rainfal Intensity 20 0.49 1.30 1.54 1.81
A=Runoff Ares,Acres 25 0.43 1.14 1.36 1.69
C=Runoff Coefficient 30 0.41 1.00 129 1.51
35 0.34 0.80 1.07 1.25
Ou=UNDEVELOPED RUNOFF,CPS(FROM PRE-DEVELOPMENT) 40 0.31 0.82 0.95 1.16
45 029 O.P 0.91 1.D7
01=INHLTRATATION,CPS 50 0.27 022 OAS 1.00
Au=Area of Infiltration at Bofiom of Pond,sf(does not Include area of sand window) 55 026 0.69 0.82 0.95
Ie=Infiltration Rate Of Native Soil et Bottom of Ponq iNM1r 60 0.28 0.69 0.82 0.96
N=AreaoflnfillralionofTrench,sf 120 0.16 0.39 0.45 0.54
la=Infil"tlon Rale of Native Soil at Bottom of Trenr ,INhr 240 0.13 0.29 0.34 0.40
Am,=Area of Infiltration at Sand W neow,sf I 360 UN 0.18 0.21 0.25
la„=Infiltration Rate of Native Sul at Bottom of Sand Window,vJhr 1 720 1 Due 0.12 1 0.14 1 did
1,=Infiltration Rate of Deeper Soil at Sand Window,I"r I 1440 I 0.04 1 0.08 1 O.o9 1 0.10
Oi=Z(A(s0-I CNMP(1 HR1360D SEC)'(1 FT1121N)
Table 2:Standard Soil Irlfilmetion Ralac'
VOLUMECALCULATION Soil Class Soil Type "Nab
A-1 Medium Sand 8
Vnet=NET VOLUME REQUIRED FOR POND ANDIOR SUMP STORAGE CF A-2b Fins Send,Loa Send 2
B-1 sandy Loam 1
Will= Orre1'IN seCmin)-Duration(min) B-2 Loam Sift Loam 0.5
61 Sandy or Sifty Clay Loam 0.2
G2 May Loam 13.15
Onet=NET DISCHARGE FLOW WHICH FILLS THE POND OR SUMP,CFS D Ciao,plank Muck Dunpan.Hardpan,Cla 4 0.09
=Od-Qu-OI 'Intimation rate determined by percolafion test my also be used
a Minimum is ..it.Wilt lam, to.afull not be Considered as
Add 25%For Sedimen candidates for infiltration facilities
Vreq= Vnelx 1.25
Vs=VOLUME OF SURFACE STORAGE,CF
Vs=V.I-Subsurface Storage Capacity
TIME OF INFILTRATION CALCULATIONS
Time to RII Subsurface Layaq sec=Volume of Subsurface StmagN Os
where Gs=SAND INFILTRATATION,CPS Modified Triangular Hydrograph
As=Nee of Trerwh or Send Wndmv
Is=Infilma0on Rate of ASTM C413 Sark=81Nhr
Gs=As(0)-Is(IND1R)-(1 HR13600 SEC)'(1 FT112 IN)
Time Und No Visible Water Exists,sec=Time to Fill Subsurface Layer+Volume Surface StOrage0i
Total Time of Infiltration,sec= Total Required VolumdQi
PAGE-7
LEAVITT S ASSOCIATES ENGINEERS,INC. JOB: Mftera
1324 1st Street South IJOB NUMBER: SD088.001
Nampa,Idaho 83651 IDATE 12fl1/2021
2081463-0333 FILE: 1 0
STORM RUNOFF CALCULATIONS-RATIONAL METHOD
POST-DEVELOPMENT FLOW
Storm Runoff for Soil Profile Test Pit# 1
Area 1 Depth(ft) Classiicati Infiltration
Rate 1
1.0 4.0 A-Ta S.OD From Park Test
Effective Area 4.0 6.0 Cemented Should Not Be
1.4,94 acres 6.0 10.0 A-2a 18.00 Excavate to Free draining materia
Design Runnoff Coefficient,C
0.65 6.0 Groundwater
Time of Concentration,Tc >16 Bedrock/Impermeable Layer
10 min
PondRrench Summary I Areas Depth ft I inlhr A x l
Infiltration at Pond Bottom 0 0.0 NA 0.00
Infiltration Area of Trench 1783 9.5 8.0 14264.00
Sand Window,or Trench Bottom 1783 11.0 8.0 14264.00
E(Axp= 28528.00 sf x inthr
Qu = Discharge flow, if allowed,see predevelompent fi 0.000 cis Assume Constant for all storm durations after to
Qi= 1783 sf x in#ir x f hr/3600 sec x lft/121n= 0.660 cis Assume Constant for all storm durations after tc
Qs= 1783 sf x 8lnlhr x 1 hr/3600sec x 1 fill 2m= 0.33 ds Assume Constant for all storm durations after to
SECONDARY RUNOFF EVENT FREQUENCY: 100 PRIMARY RUNOFF EVENT FREQUENCY: 50
Duration(Min) i(In./hr) Qd(cfs) Vnel(of) Duration Min 1(indhr) I Qdids) Vnet(cf)
10 2.58 2.055 1116,9 10 1 2.20 1.752 874.5
15 2.18 1.736 1292.6 15 1 1.86 1A81 086.4
20 1.81 1.442 1251.4 20 1.54 1.226 906.9
25 1.58 1.258 1197.5 25 1.35 1.075 830.6
30 1.51 1.203 1303.0 30 1.29 1.027 882.0
35 1.25 0.996 939.6 35 1.07 0,852 637.7
40 1.15 0.916 818.7 40 0.98 0.780 384.9
45 1.07 0.852 691.4 45 0.91 0.725 232.1
50 1.00 0.796 544.9 50 0.85 0.677 66.5
55 0.96 0.765 459.1 55 0.82 0.653 0.0
60 0.96 0.765 500.8 60 0.82 0.653 0.0
120 0.54 0.430 0.0 120 0.46 0.366 0.0
240 0.40 0.319 0.0 240 0.34 0.271 0.0
360 0.25 0.199 0.0 360 0.21 0.167 0,0
726 0.16 0.127 0.0 720 1 0.14 0.111 0.0
1440 0.10 0.080 0.0 1 1440 1 0.09 0.072 0.0
SECONDARY CONVEYANCE FLOW RATE,Q100= 2.05 cfs(at To)
PRIMARY CONVEYANCE FLOW RATE,Q50= 1.75 cfs(at To)
REQUIRED STORAGE VOLUME (Add 25
For Sediment)= 1629 cf
VOLUME OF SUBSURFACE STORAGE= 1882 cf
REQUIRED ABOVE SURFACE STORAGE VOLUME= 0 cf
TIME OF INFILTRATION INTO SUBSURFACE LAYER= 5701 sec
TIME UNTIL NO VISIBLE WATER EXISTS AFTER
PRIMARY STORM= 4718 sec= 1.31 firs<48hrs O.K.
TIME OF UNTIL NO VISIBLE WATER EXISTS AFTER
SECONDARY STORM= 5701 sec= 1.58 hrs<72hrs O.K.
DEPTH FROM BOTTOM OF FACILITY TO GROUNDWATER= 3.00 It ok
DEPTH FROM BOTTOM OF FACILITY TO BEDROCK= 30.00 ft ok
PAGE`S
LEAVITT&ASSOCIATES ENGINEERS,INC. LoB. Mitera
1324 1st Street South aoB NUMBER: SD086.001
Nampa, Idaho 83651 DATE: 2/11/2021
2081463-0333 FILE: 10
Pond&Trench Size
Area 1-Private Roadway
Total Required Storage Volume=1,629 cf
SUBSURFACE STORAGE:
SC-160LP Stormtech Storage
Stormtech Area=1,783 ftsq.
Number of Stormtech Chambers=108.0
Per Chamber Volume=17.43 cf. 14.98 cf plus.49 cf for 5"additional rock depth
Sand Window Storage Volume= (Area x Depth x Void)
1,882 cf
Total Storage Volume= 1,882 cf >Required Volume,Dimensions Good!
Required Storage Volume= 1,629 cf
Summary of Infiltration Areas
Depth from
Area(so Grade(fo Notes
Infiltration at Bottom of Pond N/A 0.0 Does not include area of sand window or trench
Infiltration Area(Bottom of Sand) N/A 6 Bottom of Trench
Sand Window or Trench Area 1783 6.0
PAGE c)
LEAVITT A ASSOCIATES ENGINEERS,INC. JOB: Miters
1324 1st Street South JOB NUMBER: SD088.001
Nampa,Idaho 83651 GATE: 2/18/2021
208/463-0333 FILE: 1 0
STORM RUNOFF CALCULATIONS-RATIONAL METHOD
POST-DEVELOPMENT FLOW
Storm Runoff for Sall Profile TBst plt# 1
Area 2 Depth(ft) Classifcati. In8 rellon
Rate I
0.0 1 1.0 C-1 0.25
Effective Area 1.0 1 6.0 B-1 1.00
1.493 acres 6.0 1 10.0 1 A-2a 18.00 Excavate to Free draining metals
Design Runnoff Coefficient,C
0.59 6.0 Groundwater
Time of Concentration,Tc >16 Bedrock/Impermeable Layer
10 min
Pondrrmnch Summary I Areas Depth ft 1 inlhr A x l
Infiltration at Pond Bottom 0 Do NA 0.00
Infiltration Area of Trench 1935 9.5 8.0 15480.00
Sand Window or Trench Bottom 1935 11.0 8.0 15480.00
£(AxI)= 30960.00 of x in01r
Ou = Discharge flow, if allowed,see predevelompem 8 0.000 cis Assume Constant for all storm durations after lc
at= 1935 at x irghr x 1hr/3600 sec x 1N12in= 0.717 cfs Assume Constant for all storn durations after tc
Os= 1935 sf x81nPorx lhr/3600sec x ifl/12in= 0.36 ds Assume Constant for all storn durations after tc
SECONDARY RUNOFF EVENT FREQUENCY: 100 PRIMARY RUNOFF EVENT FREQUENCY: 50
Duration Min I(in./hr) OtlIds) Vnet(of) Duration Min 1 pn./hr) Qtl ds Vnet(cf)
10 2.58 2.265 1240.5 10 1 2.20 1 1.932 973.3
15 2.18 1.914 1438.8 15 1.86 1 633 1101.2
20 1.81 1.589 1397.9 20 1.54 1.352 1018.1
25 1.58 1.387 1343.0 25 1.35 1.185 938.6
30 1.51 1,326 1463.9 30 1.29 1.133 999.7
35 125 1.098 1067.9 35 1.07 0.940 624.8
40 1.15 1.010 939.1 40 0.98 0.861 460.8
45 1.07 0.940 803.3 45 0.91 0.799 296.9
50 1.00 0.878 646.4 50 0.85 0.746 118.9
55 0.96 0.843 556.3 55 0.82 0.720 14.7
60 0.96 0.843 606.9 60 0.82 0.720 16.1
120 0.54 0.474 0.0 120 0.46 0.404 0.0
240 0.40 0.351 0.0 1 240 1 0.34 0299 0.0
360 0.25 0.220 0.0 360 0.21 0.184 0.0
720 0.16 0.140 0.0 1 720 1 0.14 0.123 0.0
1440 0.10 0.088 0.0 1 1440 1 0.09 0.079 0.0
SECONDARY CONVEYANCE FLOW RATE,Q100= 2.27 cfs(at Tc)
PRIMARY CONVEYANCE FLOW RATE,Q50= 1.93 cfs(at To)
REQUIRED STORAGE VOLUME (Add 25
%For Sediment)= 1830 cf
VOLUME OF SUBSURFACE STORAGE= 2092 cf
TIME OF INFILTRIATION INTO SUBSURFACE LAYER= 5837 sec
TIME UNTIL NO VISIBLE WATER EXISTS AFTER
PRIMARY STORM= 4839 sec= 1.34 hrs<48hrs O.K.
TIME OF UNTIL NO VISIBLE WATER EXISTS AFTER
SECONDARYSTORM= 7758 sec= 2.16 hrs<72hrs O.K.
DEPTH FROM BOTTOM OF FACILITY TO GROUNDWATER= 3.00 ft ok
DEPTH FROM BOTTOM OF FACILITY TO BEDROCK= 30.00 R ok
PAGE rp
LEAV/TT 8 ASSOCIATES ENGINEERS,INC. JOB: Mitera
1324 1st Street South JOB NUMBER: SD086.O01
Nampa,Idaho 83651 onre: 2/18/2021
208/463-0333 JFI E: 10
Pond&Trench Size
Area 2-Private Roadway
Total Required Storage Volume=1.830 cf
SUBSURFACE STORAGE:
SC-16OLP Stormtech Storage
Stormtech Area=1,935 ftsq.
Number of Stormtech Chambers=120.0
Per Chamber Volume=17.43 cf. 14.98 cf plus.49 cf for 5"additional rock depth
Sand Window Storage Volume= (Area x Depth x Void)
= 2,092 cf
Total Storage Volume= 2,092 cf >Required Volume,Dimensions Good!
Required Storage Volume= 1,830 cf
Summary of Infiltration Areas
Depth from
Area(so Grade(ft) Notes
Infiltration at Bottom of Pond N/A 0.0 Does not include area of sand window or trench
Infiltration Area(Bottom of Sand) N/A 6 Bottom of Trench
Sand Window or Trench Area 1935 6.0
PAGE I
LEAVITT&ASSOCIATES ENGINEERS,INC. JOB: MBera
1324 tat Street South IJOB NUMBER:ISDOSS.001
Nampa,Idaho 83651 1 DATE 1211112021
2081463.0333 FILE: 0
STORM RUNOFF CALCULATIONS-RATIONAL METHOD
POST-DEVELOPMENT FLOW
Stonrl Runoff for Soil Profile Test Pit# 1
Area 3 Depth(ft) Classificado Infiltration
Rate I
Oto 1.0 C-1 0.25
Effective Area 1.0 000 1 B-1 11.00
0.457 acres 5.0 10.0 1 A-26 18.00 Excavate to Free draining materia
Design Runnoff Coefficient,C
0.67 6.0 Groundwater
Time of Concentration,Tc >16 Bedrock/Impermeable Layer
10 min
Pond[Trench Summary I Area De ft I in/hr A x I
Infiltration at Pond Bottom 0 0.0 NA 0.00
Infiltration Area of Trench 450 9.5 8.a 3600.00
Sand Window or Trench Bottom 450 no 8.0 3600.00
£(Axl)= 7200.00 sf x in/hr
Qu = Discharge flow, If allowed,see predevelumpent fl 0.000 cis Assume Constant for all storm durations after tc
at= 450 sf x in/hr x lhr/3600 sec x lfU12!n= 0.167 cis Assume Constant for all storm durations after to
Qs= 450 six 8 in/hr x 1 hr/3600sec x 111/12in= 0.08 cis Assume Constant for all storm durations after tc
SECONDARY RUNOFF EVENT FREQUENCY: 100 PRIMARY RUNOFF EVENT FREQUENCY: 50
Duration(Min) i(InJhr) Qd(cfs) Vnet(cf) Duration Min I(in./hr) Qd(Us) Vnet(c)
10 2.58 0.790 499.6 10 2.20 0.674 406A
15 2.18 0.668 602.2 15 1.86 0.570 484A
20 1.81 0.555 621.3 20 1.54 OA72 488.8
25 1.58 0.484 635.6 25 1.35 OA14 494.5
30 1.51 0.463 711.2 30 1.29 0.395 50.2
35 1.25 0.383 606.4 35 1.07 0.328 451.8
40 1.15 0.352 594.8 40 0.98 0.300 428.0
45 1.07 0.328 580.8 45 0.91 0.279 404.2
50 1.00 0.306 559.5 50 0.85 D.260 375.4
55 0.96 0.294 561.4 55 0.82 0.251 372.5
60 0.96 0.294 612.5 60 0.82 0.251 406.4
120 0.54 0.165 0.0 120 0.46 0.141 0.0
240 0.40 0.123 0.0 240 0.34 0.104 0.0
3" 0.25 0.077 0.0 360 0.21 0.064 0.0
720 0.16 0.049 0.0 720 0.14 0.043 0.0
1440 0.10 0.031 0.0 1440 0.09 0.028 0.0
SECONDARY CONVEYANCE FLOW RATE,Q100= 0.79 Ms(at To)
PRIMARY CONVEYANCE FLOW RATE,Q50= 0.67 cfs(atTc)
REQUIRED STORAGE VOLUME (Add 25
%For Sediment)= 889 of
VOLUME OF SUBSURFACE STORAGE= 698 cf
REQUIRED ABOVE SURFACE STORAGE VOLUME= 191 cf
TIME OF INFILTRATION INTO SUBSURFACE LAYER= 8370 sec
TIME UNTIL NO VISIBLE WATER EXISTS AFTER
PRIMARY STORM= 8304 sec= 2.31 furs<48hre O.K.
TIME OF UNTIL NO VISIBLE WATER EXISTS AFTER
SECONDARYSTORM= 9519 sec= 2.64 hm<72hrs O.K.
DEPTH FROM BOTTOM OF FACILITY TO GROUNDWATER= 3.00 R ok
DEPTH FROM BOTTOM OF FACILITY TO BEDROCK= 30.00 1t ok
PAGE 1 L
LEAVITT&ASSOCIATES ENGINEERS,INC. JoB: Mitera
1324 1st Street South IJOB NUMBER ISDO86.001
Nampa,Idaho 83651 JDAM 2/11/2021
2081463-0333 FILE: 10
Pond&Trench Size
Area 3-Private Roadway
Total Required Storage Volume=889 cf
Infiltration Pond 1
Total Pond Length=75 ft. Top of Water Area= 450 sf
Total Pond Width =6 ft. Bottom of Pond Area= 0 sf
Water Depth=1.00 ft.
Side Slope= 4: 1
Freeboard= in.
Pond Storage Volume= (Top of Pond Area+Bottom of Pond Area)/2 x Water Depth
= 225 cf
SUBSURFACE STORAGE:
Sand Window Storage 1
Sand Window Area=0 ftsq.
Sand Window Depth=0.0 ft.
Void =25%
Sand Window Storage Volume= (Area x Depth x Void)
= cf
Infiltration Trench 1
Freeboard=0.00 ft.
Trench Width=6.ft. Perimeter=162 ft.
Trench Length=75 ft. Area=450 ftsq.
Gravel Depth=2.0 ft. Void of Gravel =40%
Sand Depth=3.0 ft. Void of Sand=25% Not used for storage
Trench Storage Volume= (E Area x Depth x Void)
= 698 cf
Total Above Surface Storage Volume= 225 cf
Total Subsurface Storage Volume= 698 cf
Total Storage Volume= 923 cf >Required Volume,Dimensions Good!
Required Storage Volume= 889 cf
Summary of Infiltration Areas
Depth from
Area(so Grade(ft) Notes
Infiltration at Bottom of Pond N/A 0.0 Does not include area of sand window or trench
Infiltration Area(Bottom of Sand) 450 11.5 Bottom of Trench
Sand Window or Trench Area 450 10.0
PAGE I
LEAVITT&ASSOCIATES ENGINEERS,INC. JOB: Miters
1324 1st Street South JOB NUMBER: SD086.001
Nampa,Idaho 83651 IDATE, 1211112021
208/463-0333 FILE: I0
STORM RUNOFF CALCULATIONS-RATIONAL METHOD
POST-DEVELOPMENT FLOW
Stoml Runoff for Sol]Pro01e Test Pit# 1
Area 4 Depth(It) ClassMcali Infiltration
Rate I
0te 1.0 G1 0.25
Effective Area 1.0 5.0 B-1 1.00
0.270 acres 5.0 1 10.0 A-2a 18.00 Excavate to Free draining materia
Design Runnoff Coefficient,C
0.57 >76 Groundwater
Time of Concentration,Tc Bedrock/Impermeable Layer
10 min
Pond/Trench Summary I Area Depth ft I I inmr A x I
Infiltration at Pond Bottom 0 0.0 NA I 0.00
Infitration Area of Trench 240 9.5 8.0 1920.00
Sand Window or Trench Bottom 240 11.0 8.0 1920.00
£.(Axl)= 3B40.00 sfx inlhr
Qu = Discharge flow, d allowed,see predevelompent fl 0.000 ds Assume Constant for all storm durations after to
Qi= 240 d x in/hr x 1hd 3600 sec x 1ft/12in= 0.089 ds Assume Constant for all storm durations after tc
Os= 240 sf x 8 In/hr x 1 hd 3600sec x 1ft/12in= 0A4 ds Assume Constant for all storm durations after tc
SECONDARY RUNOFF EVENT FREQUENCY: 100 PRIMARY RUNOFF EVENT FREQUENCY: 50
Duration(Min) i(in.41r) Qd(ds) Vnet(d) Duration(Min i(in./hr) I Od ds) Vnet cry
10 2.5B 0.395 244.8 10 1 2.20 1 0.336 198.3
15 2.1 B 0.333 293.7 15 1.86 0.284 234.9
20 1.81 0.277 301.0 20 1.54 0.235 234.9
25 1.58 0.242 305.8 25 1.35 0.206 235A
30 1.51 0.231 341.3 30 1.29 0.197 260.4
35 1.25 0.191 286.7 35 1.07 0.164 209.5
40 1.15 0.176 278.6 40 0.98 0.150 195.4
45 1.07 0.164 269.4 45 0.91 0.139 181.2
50 1.00 0.153 256.4 50 OAS 0.130 164.6
55 0.96 0.147 255.1 55 0.82 0.125 160.8
60 0.96 0.147 278.3 60 0.82 0.125 175.4
120 0.54 0.083 0.0 120 0.46 0.070 0.0
240 0.40 0.061 0.0 240 0.34 0.052 0.0
360 0.25 0.038 0.0 360 0.21 0.032 0.0
720 0.16 0.024 0.0 1 720 1 0.14 0.021 0.0
1440 0.10 0.015 0.0 1 1440 1 0.09 0.014 0.0
SECONDARY CONVEYANCE FLOW RATE,Q100= 0.39 cfs(at To)
PRIMARY CONVEYANCE FLOW RATE,Q50= 0.34 cfs(at To)
REQUIRED STORAGE VOLUME (Add 25
%For Sediment)= 427 cf
VOLUME OF SUBSURFACE STORAGE= 372 cf
REQUIRED ABOVE SURFACE STORAGE VOLUME= 55 cf
TIME OF INFILTRIATION INTO SUBSURFACE LAYER= 8370 sec
TIME UNTIL NO VISIBLE WATER EXISTS AFTER
PRIMARY STORM= 7847 sec= 2.18 him<48hrs O.K.
TIME OF UNTIL NO VISIBLE WATER EXISTS AFTER
SECONDARYSTORM= 8984 sec= 2.50 hrs<72hrs O.K.
DEPTH FROM BOTTOM OF FACILITY TO GROUNDWATER= 3.00 It ok
DEPTH FROM BOTTOM OF FACILITY TO BEDROCK= 30.00 It ok
PAGE 1 y
LEAVITT&ASSOCIATES ENGINEERS,INC. aoB: Mitera
1324 1st Street South JOBNUMBER: ISDO86.001
Nampa,Idaho 83651 1211112021
208/463-0333 nUE: 10
Pond&Trench Size
Area 4-Private Roadway
Total Required Storage Volume=427 cf
Infiltration Pond 1
Total Pond Length=40 ft. Top of Water Area= 240 sf
Total Pond Width =6 ft. Bottom of Pond Area= 0 sf
Water Depth=1.00 ft.
Side Slope= 4: 1
Freeboard= in.
Pond Storage Volume= (Top of Pond Area+Bottom of Pond Area)12 x Water Depth
= 120 cf
SUBSURFACE STORAGE:
Sand Window Storage 1
Sand Window Area=0 ftsq.
Sand Window Depth=0.0 ft.
Void =25%
Sand Window Storage Volume= (Area x Depth x Void)
cf
Infiltration Trench 1
Freeboard=0.00 ft.
Trench Width=6.ft. Perimeter=92 ft.
Trench Length=40 ft. Area=240 ftsq.
Gravel Depth=2.0 ft. Void of Gravel =40%
Sand Depth=3.0 ft. Void of Sand=25% Not used for storage
Trench Storage Volume= (EArea x Depth x Void)
= 372 cf
Total Above Surface Storage Volume= 120 cf
Total Subsurface Storage Volume= 372 cf
Total Storage Volume= 492 cf >Required Volume,Dimensions Good!
Required Storage Volume= 427 cf
Summary of Infiltration Areas
Depth from
Area(sf) Grade(ft) Notes
Infiltration at Bottom of Pond N/A 0.0 Does not include area of sand window or trench
Infiltration Area(Bottom of Sand) 240 11.5 Bottom of Trench
Sand Window or Trench Area 240 10.0
PAGE S
LEAVITT S ASSOCIATES ENGINEERS,INC. JOB: Milan`1324 1st Street South JOB NUMBER: SD086.001
Nampa,Idaho 83651 IDATE, 1211112021
2081463-0333 FILE: 1 0
STORM RUNOFF CALCULATIONS-RATIONAL METHOD
POST-DEVELOPMENT FLOW
Storm Runoff for Sol]Profile Test Pit# 1
Area 5 Depth(it) ClassMcati Infiltration
Rate I
0 to 1.0 G7 0.25
Effective Area 1.0 3.0 B-1 1.00
0.225 acres 3.0 1 10.0 A-2b 18.00 Excavate to Free draining materia
Design Runnoff Coefficient,C
0.53 6.0 Groundwater
Time of Concentration,Tc >16 Bedrock/Impermeable Layer
10 min
PondlTrench Summary I Area De ft I iNhr Ax I
Infiltration at Pond Bottom 0 0.0 NA 0.00
Infiltration Area of Trench 180 9.5 8.0 1440.00
Sand Window or Trench Bottom 180 1 11.0 8.0 1440.00
E(Axl)= 2880.00 sf x iruhr
Qu = Dischargeftow. Wallowed.see predevelcmperd 8 0.000 cis Assume Constant for all storm durations after to
Qi= 180 sf x In/hr x lhr/3600 sec x iN12in= 0.067 CIS Assume Constant for all storn durations after to
Os= 180 at x 8 in/hr x 1hd 3600sec x iN12in= 0.03 Cfs Assume Constant for all storm durations after tc
SECONDARY RUNOFF EVENT FREQUENCY: 100 PRIMARY RUNOFF EVENT FREQUENCY: s0
Duration Min) t(InJhr) Od(c(s) Vnet Duration(Min I(In./hr) I Qd(ds) Vnet
10 2.58 0.306 191.5 10 2.20 0.261 155.5
15 2.18 0.258 230.3 15 1.86 0.220 184.8
20 1.81 0.215 236.9 20 1.54 0.183 185.6
25 1.58 0.187 241.5 25 1.35 0.160 186.9
30 1.51 0.179 269.9 30 1.29 0.153 207.2
35 1.25 0.148 228.5 35 1.07 0.127 168.E
40 1.15 0.136 223.1 40 0.98 0.116 158.6
45 1.07 0.127 216.8 45 0.91 0.108 148.5
50 1.00 0.119 207.7 50 0.85 0.101 136.5
55 0.96 0.114 207.6 55 0.82 0.097 134.5
60 0.96 0.114 226.4 60 0.82 0.097 146.7
120 0.54 0.064 0.0 120 0.46 0.055 0.0
240 0.40 0.047 0.0 240 0.34 0.040 0.0
360 0.25 0.030 0.0 360 El 0.025 0.0
720 0.16 0.019 0.0 720 0.14 0.017 0.0
1440 0.10 0.012 0.0 1440 0.09 0.011 0.0
SECONDARY CONVEYANCE FLOW RATE,0100= 0.31 cis(at Tc)
PRIMARY CONVEYANCE FLOW RATE,Q50= 0.26 cis(at Tc)
REQUIRED STORAGE VOLUME (Add 25
For Sediment)= 337 cf
VOLUME OF SUBSURFACE STORAGE= 279 of
REQUIRED ABOVE SURFACE STORAGE VOLUME= 58 cf
TIME OF INFILTRIATION INTO SUBSURFACE LAYER= 8370 sec
TIME UNTIL NO VISIBLE WATER EXISTS AFTER
PRIMARY STORM= 8070 see= 2.24 hrs<48hrs O.K.
TIME OF UNTIL NO VISIBLE WATER EXISTS AFTER
SECONDARYSTORM= 9245 see= 2.57 hrs<72hrs O.K.
DEPTH FROM BOTTOM OF FACILITY TO GROUNDWATER= 3.00 it ok
DEPTH FROM BOTTOM OF FACILITY TO BEDROCK= 30.00 R ok
PAGE 1 6
LEAVITT 8 ASSOCIATES ENGINEERS,INC. joe: Mitera
1324 1st Street South Joe NUMBER: SD086.001
Nampa, Idaho 83651 onrE: 211112021
208/463-0333 FILE: 10
Pond&Trench Size
Area 5-Private Roadway
Total Required Storage Volume=337 cf
Infiltration Pond 1
Total Pond Length=30 ft. Top of Water Area= 180 sf
Total Pond Width =6 ft. Bottom of Pond Area= 0 sf
Water Depth=1.00 ft.
Side Slope= 4: 1
Freeboard= in.
Pond Storage Volume= (Top of Pond Area+Bottom of Pond Area)/2 x Water Depth
= 90 cf
SUBSURFACE STORAGE:
Sand Window Storage 1
Sand Window Area=0 flsq.
Sand Window Depth=0.0 ft.
Void =25%
Sand Window Storage Volume= (Area x Depth x Void)
= cf
Infiltration Trench 1
Freeboard=1.00 ft.
Trench Width=6.ft. Perimeter=72 ft.
Trench Length=30 ft. Area=180 ftsq.
Gravel Depth=2.0 ft. Void of Gravel =40%
Sand Depth=3.0 ft. Void of Sand=25% Not used for storage
Trench Storage Volume= ( Area x Depth x Void)
= 279 cf
Total Above Surface Storage Volume= 90 cf
Total Subsurface Storage Volume= 279 cf
Total Storage Volume= 369 cf >Required Volume,Dimensions Good!
Required Storage Volume= 337 cf
Summary of Infiltration Areas
Depth from
Area(so Grade(ft) Notes
Infiltration at Bottom of Pond N/A 0.0 Does not include area of sand window or trench
Infiltration Area(Bottom of Sand) 180 11.5 Bottom of Trench
Sand Window or Trench Area 180 10.0
PAGE 1 7
LEAMT 8 ASSOCIATES ENGINEERS,INC. ,oe: IMitera Mitem
1324 1st Street South �oenur+asa SD086.001 SD086.001
Nampa,Idaho 83651 oAT . 2/11/2021 2/11/2021
2081463-0333
Pipe SWna
Pipe Flow Capacity
Velocity,v=1.486/n'R' S'o
n=Mannings coefficient for roughness=0.009 for PVC
R=Hydraulic radius=Cross-sectional Area/Wetted Perimeter
s=minimum slope
Max.Flow=Qm.=Velocity'Area
pipe sin
(in) R(it) s(%n) V(8/sec) Q..cis
12 0.250 0.22 3.07 2.41
15 0.313 0.22 3.57 4.38
18 0.375 0.22 4.03 7.12
21 0.438 0.22 4.46 10.74
24 0.500 0.22 4.88 15.33
Summary of Pipe Flows
Q50 %of a Allowable Pipe
Are Pi n cfs now cis Size in
1 all 1.75 100% 1.75 12
2 all 1.93 100% 1.93 12
12
24
12
12
PAGE
LEAVITT&ASSOCIATES ENGINEERS, INC. JOB: IMitera
1324 1 at Street South IJOB NUMBER:ISDO86.001
Nampa,Idaho 83651 IDATE, 2/11/2021
2081463-0333 FILE: 10
SAND&GREASE TRAP
SAND & GREASE TRAP DESIGN
Sand & Grease Trap Capacity
Design Criterion OUTLET
Maximum Throat Velocity,1:Vm 0.5 ft/s Baffle Spacing
I L
Average Residency Time, = 20 sec. 1 7-
Equations Baffle Height
Qalimm based on Velocity=Vmu*Ai Average Length
Q.,.a based on Residency Time=Vollt
Dimensions of Amcor Product Q allowed
Baffle based
Baf0e Throat Average Height Throat Area,Al based on on t
Size allons Spacing in Width ft) Length ft (ft) (ft' Volume Vmax cis) (cfs) Q max cfs)
1000 20 4 4.26 3.92 6.67 66.80 3.33 3.34 3.33
1500 21 5.25 3.76 5 9.1875 98.70 4.59 4.94 4.59
Q50 S&G Trap %of Number of S&G Required
Area# (cfs) Used(Y/N now Q Traps Required Size(gallons)
1 1.75 Y 100% 1.75 1 1000
2 1.93 Y 100% 1.93 1 1000
3 0.00 Y 100% 0.00 0 1500
4 0.00 Y 100% 0.00 0 1500
5 0.00 Y 100% 0.00 0 1500
6 0.00 Y 100% 0.00 0 1500
PAMI q
LEAW"S ASSOCIATES ENGINEERS,INC. JOB: MBem
1324 tsl Street Souls JOBNUMBER: SD086.001
Nampa,Idaho 83651 DATE: L112D21
20814wOKK I FILE: 10.00
FLOW IN GUTTER
REF:
Izzard,C.F. "Tentative
Results on Capacity of Curb
Opening Inlets,"Research
report no.1 d-B on surface
Unit Conversion 0.560
Mannings Number,n= 0.016
Cross Slope,l/z= 0.020
Roadway Design:
Type of Street Loral Street
Min.Slope of Channel: 0.4%
Road Width(TBC): 24 R
Flow Summary.Primary Systems
Design Criteria
Number Clear lanes Required:0
Width of Clear lane Required: 0 ft
Max Depth at Roadway Crown:2 in
Matlmum Vebdy 5fps
O50 %dMw L=(Dlx) DooffisaGetten DeplialCmwn Veboy Clear Lane Width
Areas (ds) el Mmmum 0 (n) (in) tin) (fps) (h)
1 1.75 50% 0.88 9.15 1.95 ow 1.32 72 okay
2 1.0 50% 0.97 a4S 2.03 0A0 1.35 7.1 okay
3 0.67 100% O.6T Tab t.T2 0.00 1.24 9.2 okay
4 0.34 1001 0.34 5..0 1.37 D.OD 1.04 12.6 okay
6 0.25 100% 0m 5.12 124 0.00 0.98 137 okay
Flow Summary-Secondary Systems
Design CMana
Max Depth at Ginter Flow line:12 in
Max Depth at Roadway Crown:6 in
Maximum Velooty 8fps
0100 %of.caw L=(Oh) DepthatGuffin DepdalCmwn Velooly
A ilv We) atMwmum o (it) (in) IS) (fee)
1 2.05 5066 1.03 am 2.08 0.00 1.37 Okay
2 227 5056 1.13 eG 2.15 0.00 1.41 Okay
3 0.79 100% O.n 1.84 1.88 0.00 1.29 Okay
4 0.39 100% 0.39 am 1.45 0.00 1.W Okay
5 0.31 100% 0.31 s.d9 1.32 0.00 1.02 Okay
PAGES O
LGAYRF C A"OCGSED fiMOMEERF IMC. MB: MMa
IRL to S0ee1. eER:SBMa.M1
Names.MaM .51 WTEµ }I11rM11
'll"63C333 FILE: aL0
6MTE INLET CAPAC"
CRATE INLET CAPACITY BASED ON YIEIR FORMULA:
Ow=3.3'P'(H)M.5
VALUES USED
Give= CAPACRY.CFS Sea Babw
P=PERIMETER OF GRATE.FEET 4.75 FT
H•HEAD.FEET Sae Below
GRATE INLET CAPACITY BASED ON ORIFICE FORMULA:
Co-0.6'A'SQRT(2W
VALUES USED
GO=CAPACITY.CFS See Below
A- FRFEOPENAREAOFGRATESQFT 2.05 SO."
G= GRAVRY 32.20 FTISEC•3
H- HEAD.FEET So.Below
Dee]On inlet..city lane tan the lower value farweir or arnica Row.eee Um VloRmm Oalow
DepWofFlow Qw Co QDamian CHUcal Flow lot.(1)I.IeL Bimm!on Dollar Flow
INCHES OFS CFS CFS
025 0.05 1.02 0.05 Maximum Conveyance Rate= 0.97 CFS
0.50 0.13 2.01 0.13
0.75 0.26 2.47 0.2e Dept)of Flow at Maximum- 2.03 Imam
1.00 0.38 2.95 0.38
1.25 0.53 3.19 0.53
1.50 0.0 3.0 0.69
1.75 0.87 3.TS 0.87 Aetual Onle Capacity at SpeeRMO Depth.0• 1.07 LFS
2.00 1.07 E.OT 1.02
2.26 1.27 4.27 1.27
2.50 1.49 4.51 1.49
2.75 1.T2 4.73 1.TL
SAD 1.96 E.94 1.98
325 2.21 5.14 2.21 oTYPEN&LETOMTE
3.50 2A7 523 2.97
3.75 22/ B.52 274
4.00 3.02 5.70 3.02
e.25 3.30 5.87 3.30
4.50 3.60 6.06 3.60
4.75 SAID 6.21 3.90
5.00 422 0.37 e.22 _
5.25 434 6.53 4.5a Grate Qpadty
5.50 4.85 6.0 4.86
5.75 520 6.83 5.20 ••
6.00 6.541 6.98 5.64
6.25 5.0 7.12 5.89 u
6.50 6.25 7.28 6.25
6.75 6.61 7.0 6.61
700 6.98 7.54 628 1
725 7.36 7.67 7.36
7.50 7.75 7.80 7.75 •_ ____
7.75 8.14 7.93 7.93 a
B.00 8.53 9.06 9.06 wWPENIRLETGRATE - -
8.25 a." 8.18 8.18
S.50 9.34 5.31 8.31 •-
8.75 9.76 BA3 8.43
B.00 10.18 8.55 8.55 - --'---
9.25 10.61 8.67 8.67
9.50 11.0A 8.T8 an
0.75 41.,18 BSO 8.00 ° • • •mow• w
10AC 11.92 9.01 9.01
1025 1237 9.12 9.12 -.-
10.50 12.93 923 9.23
10.75 13.29 B.30 1.1
1L00 19J8 B.AS I 9.e5
Appendix I
Stormtech SC-160LP Chamber Information
FEBRUARY11,2021
StormTech SC-160LP Chamber
Designed to meet the most stringent industry performance standards for superior structural
integrity while providing designers with a cost-effective method to save valuable land and
protect water resources.The StormTech system is designed primarily to be used under
parking lots,thus maximizing land usage for commercial and municipal applications.
StormTech chambers c�,I'. -iisn be used in conjunction wiih Green n(rasiructure,thus
enhancing the performance and extending the service life of these practices.
The SC-160LP chamber was developed for infiltration and detention in shallow cover
applications
• Only 14(350 mm)required from top of chamber to bottom of pavement •.� R
• Only 12(300 mm)tall
• Installs toe to toe—no additional spacing between rows
StormTech SC-160LP(not to scale)
Nominal Chamber Specifications `
Size(LxWxH) 85.4 x 25.0 x 110(2170 x 635 x 305 Tom)
Chamber Storage 6.8513(0.19 ml
Min.Installed Storage 15.0 fN(0.42 ITS)
Weight 24.0 Its.(10.9 kg)
'Assumes 6(150 mm)stone above,4(100 mm)below and stone between
chambers with 40%stone porosity
—I 90.7'(2304 mm)ACTUAL LENGTH (—
Shipping a•(200 mm)a s•(150 mm) I I
44" CUT MARKINGS
132 chambers/pallet_ _ (112 mm) —j (— ON SOLID END CAP
144 end capslpa0 ^
et 11.7
Q 297 7 O
12 pallets/truck 18.6• III IL�
(472 Mn)
8" 85.4"(2169 mm)
(200 mm) INSTALLED LENGTH
12.0'
(305 mm) f1
25.0' —�
(635mm)
EMBOME STONESWLLLBEACIFNI.CRUSHEDMDMGUIPA G(W(UMWELLL EDWIU1 GREWTEMIK S.OS%
STOVEWMAMN 01643DESIGNATMN BETWEENBMMID147 FINES,CO FP Wr(Mmm)MPXLIFTSTOM%PROCTOR
CHAMBERS SW MEET THE REWIREMENTS FOR DENS SEETXE TABLE OF.CCEPTABLE FILL MATEfUAUS.
OR%WASTM FUIB PoLYPROPIENE IPPICHAMBERS
WFAT!MLYETNnENE(PE)CHAMBERS CNNABER331VLLBEBE DES IGNEDINMGORMkNCEWTIH FM7
STMIDMO WMCDCE MR STNU=R.LL DESIGN OF THEmA0RA571C
MSGEOSYIHETCSSBIT NOW WOVEN CORRUGATED WKL STORMWATER COLLECTION CHAMBERS'.
GEOTEMLEALLARWNDCLWLCRUSHEO, PAVIIAENT IAY WESIGNED
ANGULPREMSE➢MEMSTONE BYSRECESIGNENGWEER)
Sl IYiBlS
.. /\ 0 MIN 1 p lMm)
MIN'
MIN' MP%
JAVA-
PERISB:TERBTWE � 1T
W mmI
EXCAVATIONWALL _ _
(CMSESLOPED CEPDI OF STORE TO BE DETETUINEO
ON VERTICAL) BYSDED 113 EUMOS RPI1CUmmIMIX
tYl]OB mm)MIN—.11 ]S I`IS(]W mm) WITH GEOGRIO B%1RIGG
BROW NOBPACINCIEMBRED (635mm) T/P
BROW BETWEENCIWM0ER8
SINGLE IAYER OF GE W flID BXI24GG TO BE INSTALLED
SITE DESIGN RINGERISRESPREDBLEFOR BETWEEN NON WOVEN GEOTF%DLE PNO BASESTWE
THE EN CRINGTHE FSL(REDBEAWNG
CPPACItt OF SUBGR40E WILS
'MINIMUM COVER TO BOTTOM OF FL RE PAVEMENr.FOR UNPAVED INSTALiAnONS MERE RUTTING FROM VEHICLES MAY OCCUR INCREASE COVER TO M(510 mmT
THE INSTALLED CHAMBER SYSTEM SHALL PROVIDE THE LOAD FACTORS SPECIFIED IN ME AASHTO LRRI BRIDGE DESIGN SPECIFICATIONS SECTION 12.12 FOR EARTH AND LIVE LOADS,Wm1
CONSIDERATION FOR IMPACT AND MULTIPLE VEHICLE PRESENCES.
4 Call StormTech at 860.529.8188 or 888.892.2694 or visit our website at www.stormtech.com for technical and product information.
•
StormTech-
SC-160LP Cumulative Storage Volumes per chamber
Assumes 40%Stone Porosity.Calculations are Based Upon a 4
(100 mm)Stone Base Under Chambers. Amount of Stone Per Chamber
Wi or- :
_ 22(559) _ 685(0.194) ; 1498(0yr
424) StormTech SC-160LP 1.1(0.8) 1.2(0.9) 1.3(0.9)
_ 211533) t 6.85(0.194) - 14.49(0.410)
20(506) _ Stan 6.85(0.194) 14.00(0.396) _
19(483) Cover 6.85(0.194) 13.50(0.382) StormTech SC-160LP 952(0.7) 1,074(0.8) 1,197(0.8)
_ 18(457) _ 6.850.194 13.01(0.368) Note:Assumes 6(150 mm)of stone above and only embedment stone
_ 17(432) 6.85(0.194 12.51(0.354) between chambers.
_ 16(406) 6.85 .194 12.02(0.340)
15(381) _ 6.80(0.193) 11.49(0.325) Volume Excavation Per Chamber yd'(m')
14(356) 6.67 .189 10.92(0.309)
13 330) 6.38(0.181) 0.25(0.290)
12(305) 5.94(0.168) 9.49(0.269) StonTech SC-160LP 1.4(1.1) 1.6(1.2) 1.8(1.3)
11(279) SAO(O.153) 8.67(0.246)
10(254) 4.78(0.135) 7.81(0.221) Note:Assumes no row separation and 14(350 mm)of cover.The volume of
9 9 4.10 0.11 6.91 0.196) excavation will vary as depth of cover increases.
8 20 3.36 .095 5.97 0.169
7 78) 2.58 0,073) 5.01(0.142)
6(15 1.75(0.050) 4.02(0.114
5 1 0.89 0.025 __ 3.00.0
4 10 0(0) _ 1.98 0.05
3 Stone OR _ 1.48 0.04
2(55 Foundation 0(0) 0.119(0.028)
1 25 0(0) 0.49(0.014)
Note:Add 0.49 fN(0.014 mr)of storage for each additional inch(25 mm)of stone
foundation.
r r ..�t11 ii 1l
i l k �J � � �� ■� �; � i l l l l l � � � � I l l 1
I
111 � I f /r is a i i
�t
a
1
Ati
4.0 Foundation for Chambers StormTech•
4.1 FOUNDATION REQUIREMENTS moisture.A geotechnical engineer's recommendations
StormTech chamber systems and embedment stone may may include increasing the stone foundation,improving
be installed in various native soil types.The subgrade the bearing capacity of the sub-grade soils through
bearing capacity and chamber cover height determine compaction,replacement,or other remedial measures
the required depth of clean,crushed,angular stone for including the use of geogrids.The use of a thermoplastic
the chamber foundation.The chamber foundation is liner may also be considered for systems installed in
the clean,crushed,angular stone placed between the subgrade soils that are highly affected by moisture.The
subgrade soils and the feet of the chamber. project engineer is responsible for ensuring overall site
settlement is within acceptable limits.A geotechnical
As cover height increases(top of chamber to top of engineer should always review installation of StormTech
finished grade)the chambers foundation requirements chambers on organic soils.
increase.Foundation strength is the product of the
subgrade soils bearing capacity and the depth of 4.3 CHAMBER SPACING OPTION
clean,crushed,angular stone below the chamber foot. No spacing is required between the SC-160LP chambers.
Table 1 for the SC-1601-P,Table 2 for the SC-740 and SC- StormTech requires a minimum of 6(150 mm)clear
310,Table 3 for the SC-310-3,and Table 4 forthe DC- spacing between the feet of chambers rows for the
780 specify the required minimum foundation depth for SC-310,SC-740 and DC-780 chambers.However,
varying cover heights and subgrade bearing capacities. increasing the spacing between chamber rows may
For additional guidance on foundation stone design allow the application of StormTech chambers with either
please see our Technical Note 6.22-StormTech Subgrade less foundation stone or with weaker subgrade soils.
Performance. This may be a good option where a vertical restriction
4.2 WEAKER SOILS on site prevents the use of a deeper foundation.Contact
StormTech's Technical Service Department for more
For sub-grade soils with allowable bearing capacity less information on this option.In all cases,StormTech
than 2000 pounds per square foot[(2.0 ksf)(96 kPa)], recommends consulting a geotechnical engineer for
a geotechnical engineer should evaluate the specific subgrade soils with a bearing capacity less than 2.0 ksf
conditions.These soils are often highly variable,may (96 kPa).
contain organic materials and could be more sensitive to
TABLE 1 -SC-160LP Bearing Capacity Table
(Assumes no spacing) Minimum Required Foundation Depth in Inches(mm)
1.0 3 3 6 6 6 6 6 6 6 6 9 9 9 9 9 12 12 $3131
0.31 5 75 150 150 150 150 150 150 150 150 0 3D 2" 230 OD 300
12 3 3 3 6 6 6 6 6 6 6 fi 9 9 9 9 9 12
A 5 150 150 50 150 50 150 150 150 0 230 230 0 230
1S 3 3 3 3 3 6 6 6 6 6 6 6 9 9 9 9 9 A 5 5 5 1 150 150 150 150 50 230 230 0 30 02.0 3 3 3 3 3 3 3 3 3 3 3 6 6 6 6 6 6 0.61 5 5 150 1 1 1 1 502S 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6 6 0. 5 5 5 5 5 5 5 150 15 3.0 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 091 5 5
33b69 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6
197t01 5 5 5 150
65 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6 6
5 5 150 150
7.0 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6 6
1 5 5 75 150 150
7,5 3 1 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6 6 6
5 5 5 5 150 150 150
&0 3 3 3 3 3 3E33 3 3 3 3 3 3 3 6 6 6 6
44 5 5 5 15D 15 150 506.5 3 3 3 3 3 3 3 3 3 3 3 3 6 6 6 6 6
5 5 50 150 15 150 15099 3 3 3 3 3 333 3 3 3 6 6 6 6 6 9
74 555 5 7 150 150 50 150 150 2309S 3 3 3 3 3 3 3 3 3 3 3 fi 6 6695 5 150 150 50 150 3010.0 3 3 3 3 3 3 3 3 3 3 6 6 fi 6 9 9 9
75 5 5 150 150 150 150 30 0
NOTE:The design enyinzer,s solely responsible for assessing the bearing resistance fallmvable ice subgrade sods and determining
the depth of foundation stone.Subgrade bearing resistance should be assessed with consideration for the range of soil moisture conditions expected
under a storrnwater system.
Call StormTech at 860.529.8188 or 888.892.2694 or visit our website at www.stormtech.com for technical and product information. 17