Report 6 i7 - 0 2 C r — 3 1
•
TOC Building Site Storm Review
Drainage Report
Aug 24, 2000
TOC
Office Remodel
Tigard, Oregon
Prepared For
J.H. Seeley, Jr.
TOC Management Services
6825 SW Sandburg Street
Tigard, Oregon 97223
and
Roger Superneau
Ankrom Moisan Associated Architects
6720 S.W. Macadam
Suite 100
Portland, Oregon 97219
Prepared By:
Brent Sanborn, P.E.
WRG Design Inc.
10450 SW Nimbus
Portland, Oregon 97223
0
• .y�i'V ` 1 I
D E S I G N I N C.
• 8/22/00 3:4:44 pm WRG Design Inc. page 1
TOC BUILDING ADDITION
CITY OF TIGARD PLAN REVIEW
3. SANBORN
BASIN RESULT SUMMARY
BASIN VOLUME ---- -RATE- -- --TIME Hydrograph Area
ID - - -cf -- Ac -ft - -cfs -min- hours Methodology - -Ma
POST10 2965 0.07 0.20 490 8.17 SCS Method 0.25
POST2 2263 0.05 0.15 490 8.17 SCS Method 0.25
POST25 5997 0.14 0.40 500 8.33 SCS Method 0.50
POSTS 2614 0.06 0.18 490 8.17 SCS Method 0.25
PRE10 1918 0.04 0.13 490 8.17 SCS Method 0.25
PRE2 1307 0.03 0.08 500 8.33 SCS Method 0.25
PRE25 5165 0.12 0.35 500 8.33 SCS Method 0.50
PRES 1608 0.04 0.10 500 8.33 SCS Method 0.25
4 2 y g- e 6)-46 cf-s
w a 2y12. D. 32) X D• b5 cfs D . 0'S cF
T L i
C �-
De- yQ. PaR vs. Po sT : D. 4o - o .35 = 0. os e fs
-�` D eTtr9167 of D.oS -f5
* L2) 1"P -1 PCiz 14/0 uarr to MNleup
- F;itz_in i rpc j tie 4ArA-6,.e M T.
Dststntion System
. .
8/22/00 3:4:44 pm WRG Design Inc. page 2
TOC BUILDING ADDITION
CITY OF TIGARD PLAN REVIEW
B. SANBORN
STORAGE STRUCTURE LIST
UNDERGROUND PIPE ID No. PIPE
Description: 24" storm detention pipe
Diameter: 2.50 ft. Length,: 55.00 ft.
Slope...: 0.0010 ft /ft upstr: dnstr:
•
•
•
•
•
•
8/22/00 3:4:45 pm WRG Design Inc. page 3
TOC BUILDING ADDITION
CITY OF TIGARD PLAN REVIEW
B. SANBORN
DISCHARGE STRUCTURE LIST
MULTIPLE ORIFICE ID No. ORIFICE1
Description: MULTIPLE ORIFICE
Outlet Elev: 100.00
Elev: 100.00 ft Orifice Diameter: 3.1289 in.
•
ILL
8/22/00 3:5:17 pm WRG Design Inc. page 5
TOC BUILDING ADDITION
CITY OF TIGARD PLAN REVIEW
B. SANBORN
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <- PEAK -> STORAGE
DESCRIPTION > (cfs) (cfs) - -id - -id c- STAGE> id VOL (cf)
0.35 0.40 PIPE ORIFICE1 101.70 1 191.61 cf
•
•
•
•
•
uogeu.uojuE Li
8/22/00 3:5:15 pm WRG Design Inc. page 1
TOC BUILDING ADDITION
CITY OF TIGARD PLAN REVIEW
B. SANBORN
BASIN SUMMARY
BASIN ID: POST10 NAME: .POST DEVELOPMENT 10 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.25 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION 3.60 inches AREA..: 0.00 Acres 0.25 Acres
TIME INTERVAL 10.00 min CN 0.00 98.00
TC • 0.00 min 5.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.20 cfs VOL: 0.07 Ac -ft TIME: 490 min
BASIN ID: POST2 NAME: POST DEVELOPMENT 2 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.25 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION 2.80 inches AREA..: 0.00 Acres 0.25 Acres
TIME INTERVAL 10.00 min CN 0.00 98.00
TC 0.00 min 5.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.15 cfs VOL: 0.05 Ac -ft TIME: 490 min
BASIN ID: POST25 NAME: POST DEVELOPMENT 25 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.50 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION - 4.00 inches AREA..: 0.14 Acres 0.35 Acres
TIME INTERVAL 10.00 min CN 86.00 98.00
TC 5.00 min 5.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.40 cfs VOL: 0.14 Ac -ft TIME: 500 min
BASIN ID: POSTS NAME: POST DEVELOPMENT 5 YR EVENT
SCS METHODOLOGY
TOTAL AREA • 0.25 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION 3.20 inches AREA..: 0.00 Acres 0.25 Acres
TIME INTERVAL 10.00 min CN 0.00 98.00
TC 0.00 min 5.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.18 cfs VOL: 0.06 Ac -ft TIME: 490 min
l
. 8/22/00 3:5:15 pm WRG Design Inc. page 2
TOC BUILDING ADDITION
CITY OF TIGARD PLAN REVIEW
B. SANBORN
BASIN SUMMARY
BASIN ID: PRE10 NAME: PRE DEVELOPMENT 10 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.25 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION 3.60 inches AREA..: 0.25 Acres 0.00 Acres
TIME INTERVAL 10.00 min CN 86.00 0.00
TC 5.00 min 0.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.13 cfs VOL: 0.04 Ac -ft TIME: 490 min
BASIN ID: PRE2 NAME: PRE DEVELOPMENT 2 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.25 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION 2.80 inches AREA..: 0.25 Acres 0.00 Acres
TIME INTERVAL 10.00 min CN 86.00 0.00
TC 5.00 min 0.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.08 cfs VOL: 0.03 Ac -ft TIME: 500 min
BASIN ID: PRE25 NAME: PRE DEVELOPMENT 25 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.50 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION 4.00 inches AREA..: 0.34 Acres 0.16 Acres
TIME INTERVAL 10.00 min CN 86.00 98.00
TC 5.00 min 5.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.35 cfs VOL: 0.12 Ac -ft TIME: 500 min
BASIN ID: PRES NAME: PRE DEVELOPMENT 5 YR EVENT
SCS METHODOLOGY
TOTAL AREA 0.25 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE TYPE1A PERV IMP
PRECIPITATION - 3.20 inches AREA..: 0.25 Acres 0.00 Acres
TIME INTERVAL 10.00 min CN 86.00 0.00
TC 5.00 min 0.00 min
ABSTRACTION COEFF: 0.20
PEAK RATE: 0.10 cfs VOL: 0.04 Ac -ft TIME: 500 min