HomeMy WebLinkAboutSWP272241(2) LA COLINA
' City of Renton, Washington
Frontage Conveyance Capacity
' Prepared by:
Todd A. Oberg
' Reviewed by:
tBrian J. Darrow, P.E.
1
RECEIVED
JUN 2 5 1996
PLAN REVIEW
' June 25, 1996 Triad Job No. 94-130
' TABLE OF CONTENTS
' PAGE
INTRODUCTION......................................................................................................... 1
VICINITYMAP............................................................................................................2
' FRONTAGE CONVEYANCE CAPACITY................................................................3
OPTION1 .........................................................................................................................3
' OPTION 2.........................................................................................................................4
OPTION3 ......................................................................................................................... 5
DETENTION CALCULATIONS.................................................................................6
WATERQUALITY......................................................................................................7
' CONCLUSION.............................................................................................................7
' APPENDIX
' Existing Conveyance System Map
Option 1 Summary Table
' Option 2 Summary Table
Option 3 Summary Table
' Curve Numbers Table
Water Works Output
' Developed Conditions Map
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FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE i
' INTRODUCTION
The proposed project is to construct 138 single family residents on approximately 46 acres
' of land. Of the 46 acres, approximately 29.3 acres will be developed while leaving the
remaining in its existing condition. The site is located just east of I-405 on the north side
' of Maple Valley Road, please refer to the Vicinity Map located on the following page.
More generally, the site lies within Section 17, Township 23 North, Range 5 East, W.M..
' Access to the site will be from the north via the southerly extension of Edmonds Ave. NE
' from NE 3rd Street. The site is a gravel mine with very little natural vegetation remaining.
The site is situated on a high, steep hillside above Maple Valley Highway (SR-169). The
' site slopes generally in a westerly direction. Most of the storm runoff currently percolates
into the existing soils;very little, if any at all, flows over the steep slope.
' FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE I
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' FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE 2
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FRONTAGE CONVEYANCE CAPACITY
' The existing conveyance system located on SR-169 downstream of the La Colina site
consists of a tightlined system with catch basins located on each side of the highway.
' Please refer to the Existing Conveyance System Map located in the Appendix. To
' determine the allowable release rate from the La Colina site, the existing downstream
conveyance system capacity was checked using the Storm Sewers program. This program
calculates the Hydraulic Grade Line (HGL) for the system using the Rational Method with
the 25-year 24-hour storm event. Th8 availa'b'.c caoac;— --a� cal plated by determining
the existing tributary flows and then calculating the amount of additional flow that could
k be introduced into the system at various connection points without causing flooding
during the 100-year storm event,
r r
' Option 1
For Option 1, the flow into C134 was increased until the existing system reached capacity
' without flooding during the 100-year storm event. The Summary Table for Option 1
located in the Appendix, contains the hydraulic grade line analysis results. The following
' is the 100-year freeboard table for Option 1:
' Freeboard Table (Option 1
Catch Basin Rim Elev. HGL Elev. Freeboard
' 10111 48.58 44.00 4.58
NM 57.58 45.38 12.20
CBI 56.00 46.99 9.01
C132 54.13 48.77 5.36
' CB3 53.94 50.94 3.00
CB4 53.91 53.89 0.01
C136 54.75 54.41 0.34
' C137 56.02 54.67 1.35
' • The allowable outfall into C134 was calculated to be 5.7 cfs with no changes to the
existing conveyance system.
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FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE 3
Option 2
' For Option 2, the conveyance pipe connecting C133 and CB4 was changed from a 12 inch
to an 18•inch then the flow into C134 was increased until the system reached capacity
' without flooding during the 100-year storm event. The Summary Table for Option 2
located in the Appendix, contains the hydraulic grade line analysis results. The following
is the 100-year freeboard table for Option 2:
Freeboard Table (Option 2
' Catch Basin Rim Elev. HGL Elev. Freeboard
MHl 48.58 44.25 4.33
NM 57.58 45.73 11.85
' CB1 56.00 47.38 8.62
C132 54.13 49.07 5.06
C133 53.94 52.61 1.33
' C134 53.91 53.84 0.06
C136 54.75 54.37 0.38
CB7 56.02 54.63 1.39
The allowable outfall into CB4 was calculated to be 9.8 cfs after changing the
' conveyance pipe connecting C133 and C134 from a 12 inch to an 18 inch.
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FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE 4
OOvtion 3
' For Option 3, the flow into CB3 was increased until the existing system reached capacity
without flooding during the 100-year storm event. The Summary Table for Option 3
' located in the Appendix, contains the hydraulic grade line analysis results. The following
is the 100-year freeboard table for Option 3:
' Freeboard Table(Option 3
Catch Basin Rim Elev. HGL Elev. Freeboard
NMI 48.58 44.38 4.20
NIM 57.58 45.87 11.71
CBI 56.00 47.58 8.42
CB2 54.13 49.24 4.89
CB3 53.94 53.40 0.54
CB4 53.91 53.62 129
CB6 54.75 54.15 0.60
' CB7 56.02 54.41 1.61
• The allowable outfall into CB3 was calculated to be 11.4 cfs with no changes to the
' existing conveyance system.
' FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE 5
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DETENTION CALCULATIONS
' To determine the maximum runoff from the developed site, the 100-year, 24-hour
' hydrograph was generated using the Water Works program methodology (please refer to
the Appendix for the actual computer output). The soils on the site were determined to
mainly consist of hydraulic group `A' which translates to the following runoff curve
numbers(please refer to Curve Numbers Table located in the Appendix):
tPervious CN=68 (lawns and landscaping in good condition)
Impervious CN=98 (roofs, roads, sidewalks, etc...)
Time of Concentration (T�) =21.14 min.
' 135' Sheet @ 3.7%, ns-0.15
100' SCF @ 2.00/.,ks=27.00
1510' Channel @ 0.52%/ kc 42.00
' 225' Channel @ 97%,kc--42.00
Developed Conditions H dro ra h
' tAbstraction
ll Userl Time of Conc. 21,14 min.
ows 0.00 as Total Area 33.20 Ac.
Cceff. 0.20 Pervious Area 19.09 Ac. CN�8
nterval 10.00 min. Ln rvious Area 14.11 Ac. CN=98
Developed Conditions H dro ra h Summary
Storm Precip. Peak Flow Volume Time of Peak
in cfs Ac-ft min
100- ear 3.90 13.71 6.13 480
As shown in the above tables, the 100-year runoff from the site is 13.71 cfs which is
' greater than the existing capacity of 11.40 cfs, therefore, the allowable release rate is
11.40 cfs per Option 3 in the Frontage Conveyance Capacity section of this report.
' FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE 6
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' Through the use of level pool routing, using the allowable release rate of 11.40 cfs for the
' 100-year 24-hour storm event, a required live storage volume was calculated. Following
is the level pool table computed from routing the 100-year developed hydrograph through
' an 18 inch orifice releasing 11.40 cfs:
Level Pool Table Summary
' Description Inflow Storage Discharge P. Stage Volume Outflow P. Time
cfs ID I ID ft ft' cfs min.
100 YR STORM 1 13.71 1 VAUL I DIS1 1 101.68 1 6715.78 1 11.39 1460
' Therefore, the required live storage volume is approximately 6,720 W.
' WATER QUALITY
' Water quality enhancement will be provided through the use of dead storage in the vault.
' To determine the volume of dead storage required, a hydrograph was created use 1/3 of
the 2 year rainfall precipitation in the developed conditions. Following is a summary of
t the water quality hydrograph:
Storm Precip. Peak Flow Volume Time of Peak
in cfs) (Ae-ft) (min
' Water Quality 0.67 1.44 0.56 480
' Therefore, the volume of dead storage required is 24,333 ft3.
' CONCLUSION
The total required storage volume is 31,055 ft3 (6,720 ft3 (live) + 24,333 ft3 (dead)),
therefore, the vault will be 40 ft x 100 ft x 9 ft deep, which provides a storage volume of
' 31,200 ft3. The release structure will consist of an 18 in. down-turned elbow with an
outfall elevation set at 6.10 ft above the bottom of the vault. The maximum water surface
' will be at an elevation of 7.80 ft from the bottom of the vault, which allows for 1.20 ft of
freeboard.
' FRONTAGE CONVEYANCE CAPACITY FOR LA COLINA-PAGE 7
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EXISTING CONVEYANCE SYSTEM MAP
' 06/24/96 STORM SEWER SUMMARY REPORT
La Colina - 100-yc storm 5.1 cfs outfall into CB4 w/ existing conveyance system
FILE: LACOLINA.STM
' RAINFALL FILE: RENTON.RND 100 YEAR DESIGN STORM I - 10.190/ ( To + 0.000) ^ O.630
LINE11 DESCRIPTION JINC AR RUNOFFC INLTIME INLT I INC CIA INPUTQ IUNIFORMISIZE/I INVERT PIPE NVAL HGLSLOPEIHYD GRD I VEL
' DOWNLINE4 TOT AR I WEIGITD� Tc ITOTL IITOT CIAI TOTALQ FLONCAPITYPE UP/DOWN �LEN INVSLOP JLC UP/DL484 UP/DOWN
(ac) C in (in/A) (cfs) (cfs) I (cfs) (in) (fq (ft) (ft/fq (ft/ft) l (ft) I (ft/s)
1 HHl I 0.01 0.90 6.30I 3.20 0.00 0.00 24D� 41.80I 55I 0.012I 0.002 43.66 5.40
' DNLN - 0 3.5 0.87 12.71 2.05 6.10 16.40 25.6 24D 41.20 I 0.011 0.75 43.58 5.24
6.84
2 MR2
7 12B 05 DNLN - 1 3.51 0.8 12.36 2.09 6.29 16.59 25.7 24D 41.80 0.011 1.00 44.00I 5.28
3 CB1 0.7 0.911 6.311 3.20 2.01 0.00 24D 14.62 201� 0.012 0.003 46.07� 6.87
DNLN - 2 3.5 0.87 11.81 2.15 6.47 16.77 20.5 24D 43.21� I 0.007 1.25 45.30 5.34
' 4 CB2 0.5 0.90� 6.30 3.20 1.44 0.00 24D 46.85I 3401 0.012 0.004 40.25 6.67
DNLN - 3 2.6 0.86 10.84 2.21 5.40 15.70 19.8 24D 44.62 0.007 0.15 46.99 5.00
' S CB3 1.1 0.90 6.30 3.20 3.16 4.60 18D 47.43 66 0.012 0.008 49.32 6.32
DNLN - 4 2.2 0.06 10.71 2.29 4.41 14.711 11.7 1BD 46.73 0.0111 1.50 I 48.77 6.32
I� 1 1 1
6 CH4DNLN - 5 1.1 0.82 10.66 2.29 2.15I 1.05 2.11 12D 5.70 12D 16,77 30 0.003 3 5023I 51.54 10.00
50.94 10. 0
0.012 1
' 7 i CB DNLN - 6 1.0 0.90 9.21I 2.52 2.26 2.26 2.0 12DI 40.77 250 0.005 0 7502 53.89 2.88
8 C87 0.5 0.90 6.30 3.20 1.44 0.00 I 12DI 51.51 320I 0.012 0.001 54.671 1.83
' DNLN - 7 0.5I 0.90I 6.301 3.201 1.44 1.44I 2.61 12D 50.06 0.005 0.75 54.411 1.83
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06/24/96 STORM SEWER CUSTOM REPORT
La Colina- 100-yr storm 5.7 cfs outfall into CB4 w/existing conveyance system
' Catch Basin Rim Elev. HGL Elev. Freeboard
MHl 48.58 44.00 4.58
' MH2 57.58 45.38 12.20
CBI 56.00 46.99 9.01
CB2 54.13 48.77 5.36
' CB3 53.94 50.94 3.00
CB4 53.91 53.89 0.01
CB6 54.75 54.41 0.34
CB7 56.02 54.67 1.35
' 06/24/96 STORM SEWER SUIMRY REPORT
La Colina - 100-yr storm 9.8 cfs outfall into CB4 and change 12" to a 18"
FILE: LACOLINA.STM
tRAINFALL FILE: RENTON.RND 100 YEAR DESIGN STORM I - 10.190/ ( Tc + 0.000) ^ 0.630
LINEI DESCRIPTION IIM ARIRUNOFFCIINLTIMEIINLT I INC CIA) INPUTQ (UNIFORM SIZE/IINVERT IPIPE I NVAL IHGLSLOPEIHYD GRD I VEL
' I DOWNLINE# ITOToARI WEICHTDI Tc ITOTL I�TOT CIAI TOTALQ IFLCFCAPITYPE IUP/DOWN 1(ft)
IINVSLOPI JLC IUP/DOWN IUP/DOWN
( ) I (min) I(in/h) (cfs) I (cfs) (cfs) kin) I (ft) (ft) I(ft/ft)I (ft/ft)I (ft) I (ft/3)
1 I FBN1 I 0.0 0.90I 6.301 3.201 0.00I 0.00 I 24DI 41.80I 55 0.0121 0.003I 43.741 6.63
DNLN - 0 3.5 0.87 12.431 2.08 6.26 20.66 25.61 24DI 41.20I 0.011 0.75 43.5BI 6.58
2 I MN2 I 0.0I 0.90) 6.301 3.20 0.00I 0.00I 24DI 43.21I 128I 0.012I 0.004 44.821 7.65
DNLN - 1 I 3.5 0.87 12.131 2.12 6.36I 20.76I 25.7 24DI 41.80 0.011I 1.00 I 44.251 6.61
' 3 I Cal I 0.7I 0.90I 6.301 3.201 2.01I 0.00I I 24DI 44.62 201I 0.012I 0.003I 46.261 7.58
DNLN - 2 I 3.5I 0.87 11.661 2.17I 6.52 20.921 20.5I 24DI 43.21 0.007I 1.25 I 45.73 6.66
4 I CB2 0.5 0.90I 6.30 3.20I 1.44 0.001 24D� 46.85 340� 0.012� 0.003I 48.43 7.46
DNLN - 3 2.8 0.06I 10.84I 2.27I 5.40 19.801 19.0I 24D 44.62 0.007 0.75 47.38 6.30
5 I C83 1.1I 0.90I 6.301 3.20I 3.16 4.60I I 18DI 47.43I 66I 0.012 0.014 49.97 10.64
' DNLN - 4 2.2I 0.66 10.731 2.28I 4.40 10.80 11.7I 18D 46.73I I 0.011 1.50 49.071 10.64
6 I CB4 0.2 0.25 6.30 3.20 0.12 9.801 18D) 48.36 30 0.012 0.006 52.78I 6.76
DNLN - 5 1.1 0.82 10.66 2.29 2.15 11.95 18.6 18D 47,54 0.027 1.50 52.61 6.76
7 I Ce6 0.5I 0.90 6.301 3.201 1.44I 0.001 1 12D 50.07� 250I 0.012I 0.002I 54.271 2.88
t I DNLN - 6 1.OI 0.90I 9.211 2.521 2.26I 2.261 2.81 12DI 48.77 I 0.005 0.75 I 53.841 2.88
6 I CE7 I 0.51 0.90I 6.301 3.201 1.44) 0.001 I 12DI 51.34 320I 0.012I 0.001� 51.63 1.63
' I DNLN - 7 I 0.51 0.90I 6.301 3.201 1.44I 1.44I 2.41 12DI 50.06 I 0.004I 0.75 54.371 1.83
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06/24/96 STORM SEWER CUSTOM REPORT
La Colina- 100-yr storm 9.8 cfs outfall into CB4 and change 12"to a 18"
Catch Basin Rim Elev. HGL Elev. Freeboard
MHl 48.58 44.25 4.33
NM 57.58 45.73 11.85
CBI 56.00 47.38 8.62
CB2 54.13 49.07 5.06
' CB3 53.94 52.61 1.33
CB4 53.91 53.84 0.06
CB6 54.75 54.37 0.38
CB7 1 56.02 54.63 1.39
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' 06/24/96 STORM SEWER SUMMARY REPORT
La Colina - 100-yr storm 11.4cfa outfall into CB3 w/ existing conveyance system
FILE: LACOLINA.STM
' RAINFALL FILE: RENTON.RND 100 YEAR DESIGN STORM I - 10.190/ ( To ♦ 0.0001 " 0.630
LINEfj DESCRIPTION ZINC ARI RUNOFFCIINLTIME INLT IIINC CIAI INPUTQ IUNIFORMISIZE/IINVERT PIPE I NVAL HGLSLOP£ HYD GRD VEL
' I DOWNLINEt TOT ARIWEIGHTDI Tc ITOTL I TOT CIA TOTALQ FLOACAPITYPE IUP/DCWN ILEN INVSIAPI JI.0 UP/DOWN UP/DOWN
(ac) C (min) (in/h)I Icfs) (cfs) (cfs) (i n) I (ft) (ft) Ilft/f t) (ft/ft) Ift) (f[/s)
I I
1 I Mil 0.01 0.90I 6.301 3.20I O.00I O.00I 1 24DI 91.80 SSI 0.012I 0.004I 43.791 7.08
DNLN - 0 I 3.5 0.87I 12.49 2.08 6.24I 22.241 25.6I 24DI 41.201 I 0.01111 0.75 I 43.581 7.08
2 I MH2 0.OI 0.90I 6.30I 3.20 0.00I O.00I 24DI 43.21I 1281 0.012I 0.004I 44.881 7.96
DNLN - 1 I 3.5I 0.67I 12.21I 2.11I 6.33I 22.331 25.7I 24D 41.80I 0.011 1.00 44.38I 7.11
' 3 I C81 0.7I 0.90I 6.30I 3.20I 2.O1 0.001 I 24DI 44.62I 201I 0.012� 0.004I 46.571 7.21
DNLN - 2 3.51 0.071 11.74 2.16I 6.49 22.491 20.5I 24DI 43.23I 0.007 1.25 45.871 1.16
4 C82 0.5 I I0.901 6.30 3.20II 1.4I I I 24DI 46.85I 340I 0.012 0.003 48.631 7.22
3 2.B 0.86 10.94 2.26 5.37 OOO1
DNLN . 19.8 24DI 44.62I 0.007� 0.75 I 47.581 6.80
' S I CB3 I 1.1 0.90I 6.30 3.20 3.16I 16.00I I 18DI 41.43I 66I 0.012 0.016I 50.30I 11.53
DNLN - 4 I 2.21 0.66I 10.84 2.27I 4.381 20.38I 11.71 18 DI 46.73I 0.011. 1.50 I 49.241 11.53
6 CB4 0.2I 0.251 6.30I 3.20I 0.12I 0.00 1 12DI 48.06I 30I 0.0121 0.002I 53.44I 2.74
DNLN - 5 1.1I 0.82 10.66I 2.29I 2.15I 2.15I 2.11 12D 48.771 I 0.003I 1.50 I 53.40i 2.74
1 7 C86 I 0.5I 0.901 6.30I 3.20I 1.44 0.00I I 12DI 50.07 250I 0.012I 0.002 54.05I 2.88
DNLN - 6 1.0 0.90 9.21I 2.52I 2.261 2.26 2.0 12D 48.77I I 0.005 0.75 I 53.62 2.86
1.83
8 CBDNLN - 7 i 0.51 0.90I 6.30I 3.20I 1.441 1.44, 2.6. 12DI 50.061 320I 0.0051 0.750.0121 0. 01I 54.15� 1.83
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' 06/24/96 STORM SEWER CUSTOM REPORT
La Colina- 100-yr storm 11.4cfs outfall into CB3 w/existing conveyance system
' Catch Basin Rim Elev. HGL Elev. Freeboard
MHl 48.58 44.38 4.20
MH2 57.58 45.87 11.71
CBI 56.00 47.58 8.42
CB2 54.13 49.24 4.89
' CB3 53.94 53.40 0.54
CB4 53.91 53.62 0.29
CB6 54.75 54.15 0.60
CB7 56.02 1 54.41 1.61
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' KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
' TABLE 3.5.213 SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS
SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS (Published by SCS in 1982)
' Runoff curve numbers for selected agricultural, suburban and urban land use for Type to
rainfall distribution, 24-hour storm duration.
CURVE NUMBERS BY
' HYD LOGIC SOIL GROUP
LAND USE DESCRIPTION A B C D
Cultivated land(1): winter condition 86 91 94 95
' Mountain open areas: low growing brush and grasslands 74 82 89 92
Meadow or pasture: 65 78 85 89
' Wood or forest land: undisturbed or older second growth 42 64 76 81
Wood or forest land: young second growth or brush 55 72 81 86
Orchard: with cover crop 81 88 92 94
Open spaces, lawns, parks, golf courses, cemeteries,
landscaping.
good condition: grass cover on 76%
' or more of the area 80 86 90
fair condition: grass cover on 50%
to 75% of the area 77 85 90 92
Gravel roads and parking lots 76 85 89 91
Dirt roads and parking lots 72 82 87 89
Impervious surfaces, pavement, roofs, etc. 98 98 98
Open water bodies: lakes, wetlands, ponds, etc. 0 1080 100 100
tSingle Family Residential (2)
Dwelling Unit/Gross Acre % Impervious (3)
' 1.0 DU/GA 15 Separate curve number
1.5 DU/GA 20 shall be selected
2.0 DU/GA 25 for pervious and
2.5 DU/GA 30 impervious portion
3.0 DU/GA 34 of the site or basin
3.5 DU/GA 38
4.0 DU/GA 42
4.5 DU/GA ' 46
t 5.0 DU/GA , -•_48'
5�l7/GA 50
6.0 DU/GA 52 W
6.5 DU/GA 54' m 7.0 DU/GA 56
Planned unit developments, % impervious ~
condominiums, apartments, must be computed N
' commercial business and
industrial areas. Wm
(1) For a more detailed description of agricultural land use curve numbers refer to National Engineering
Handbook, Section 4, Hydrology, Chapter 9, August 1972.
(2) Assumes roof and driveway runoff is directed into street/storm system. Z
(3) The remaining pervious areas (lawn) are considered to be in good condition for these curve numbers.
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3.5.2-3 11/92 U
' 6/21/96 TRIAD Associates
LA COLINA
SOILS TYPE A
' BASIN SUMMARY
' BASIN ID: Cl NAME: WATER QUALITY
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 33 . 20 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 0. 67 inches AREA. . : 19 . 09 Acres
TIME INTERVAL. . . . : 10. 00 min CN. . . . : 68. 00
TIME OF CONC. . . . . : 21. 14 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 14 . 11 Acres
CN. . . . 98. 00
TcReach - Sheet L: 135 . 00 ns: 0. 1500 p2yr: 2 . 00 s: 0.0370
' TcReach - Shallow L: 200. 00 ks:27 . 00 s: 0. 0200
TcReach - Channel L: 1400. 00 kc: 42 . 00 s: 0. 0050
TcReach - Channel L: 225. 00 kc:42 . 00 s: 0.9700
' PEAK RATE: 1. 44 cfs VOL: 0. 56 Ac-ft TIME: 480 min
t
' BASIN ID: B3 NAME: 100 YR DEVELOPED
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 33 . 20 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 19 . 09 Acres
TIME INTERVAL. . . . : 10. 00 min CN. . . . : 68 . 00
' TIME OF CONC. . . . . : 21. 14 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0. 20 AREA. . : 14 . 11 Acres d
CN. . . . : 98 . 00 �-
TcReach - Sheet L: 135 . 00 ns: 0. 1500 p2yr: 2 . 00 s: 0 . 0370' O TcReach - Shallow L: 200 . 00 ks: 27 . 00 s: 0. 0200
TcReach - Channel L: 1400 . 00 kc: 42 . 00 s: 0. 0050 U)
TcReach - Channel L: 225. 00 kc: 42 . 00 s: 0 . 9700 �
' PEAK RATE: 13 . 71 cfs VOL: 6 . 13 Ac-ft TIME: 480 min O
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' 6/24/96 TRIAD Associates page 1
LA COLINA
' SOILS TYPE A
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' LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAK-> STORAGE
' <--------DESCRIPTION-------—>--(cfs) _(cfs)---iid____id_<STAGE=_id VOL-(cf)
100 YR STORM ................. 11.40 13.71 VAUL1 D1S1 101.68 9 6715.78
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' 6/25/96 TRIAD Associates page 1
LA COLINA
' SOILS TYPE A
-------- ----------------HYDROGRAPH SUMMARY
' PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
t NUM RATE PEAK HYDRO Area
cfs rain. cf\AcFt Acres
' 6 13 .713 480 266887 cf 33 .20
9 11.392 500 266887 . cf 33 .20
10 1.435 480 24333 cf 33.20
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