Drainage Report
Drainage Report:
6444 Murray Hill Rd.
Chanhassen, MN
CITY OF CHANHASSEN
RECEIVED
OCT 1 2 2007
CHANHASSEN PLANNING DEPT
Prepared by:
Matt Pavek, P.E.
TERRA ENGINEERING, INe.
6001 Glenwood Ave.
Golden Valley, MN 55422
(763) 593-9325
10/12/07
TERRA ENGINEERING
6444 MURRAY HILL RD.
10/12/2007
PREPARED BY: MATT PAVEK, PE
DRAINAGE REPORT SUMMARY
ASSUMPTIONS:
TYPE II 24 HOUR STORM EVENT
TYPE "CO SOILS
EXISTING SITE ASSUMED TO BE GRASS IN FAIR CONDITION
PROPOSED SITE ASSUMED TO BE GRASS IN FAIR CONDITION
STORM EVENT
2-YR
10-YR
100- YR
EXISTING RUNOFF (CFS)
1.65
3.23
5.38
PROPOSED RUNOFF (CFS)
1.84
3.46
5.62
.. . .... ,'"
:1......S> ,.j, .;'
, ....-,.. -
,:. ,'. . ",:-:
.. ..- "
. '
EXISTING SITE
28
PROPOSED SITE
~Ubc1 B ~ ~
Drainage Diagram for 6444 MURRAY HILL
Prepared by Terra Engineering Inc. 10/12/2007
HydroCAD@7.00 sin 001544 @ 1986-2003 Applied Microcomputer Systems
6444 MURRAY HILL
Prepared by Terra Engineering Inc.
HydroCAD@7.00 sin 001544 @ 1986-2003 Applied Microcomputer Systems
Type /I 24-hr 2 YEAR Rainfal/=2.80"
Page 2
1 0/12/2007
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+ Trans method - Pond routing by Stor-Ind method
Subcatchment 15: EXISTING 51TE
Runoff Area=50,071 sf Runoff Depth=1.11 II
Flow Length=200' Tc=17.7 min CN=82 Runoff=1.65 cfs 0.107 af
Subcatchment 25: PROPOSED SITE
Runoff Area=50,071 sf Runoff Depth=1.24"
Flow Length=200' Tc=17.7 min CN=84 Runoff=1.84 cfs 0.119 af
Total Runoff Area = 2.299 ac Runoff Volume = 0.225 af Average Runoff Depth = 1.18"
6444 MURRAY HILL
Prepared by Terra Engineering Inc.
HydroCAO@ 7.00 sIn 001544 @ 1986-2003 Applied Microcomputer Systems
Type /I 24-hr 2 YEAR Rainfal/=2.80"
Page 3
1 0/12/2007
Runoff =
Subcatchment 1S: EXISTING SITE
1.65 cfs @ 12.11 hrs, Volume=
0.107 af, Depth= 1.11"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 YEAR Rainfall=2.80"
Area (sf)
6,646
43,425
50,071
CN Description
100 IMPERVIOUS
79 50-75% Grass cover, Fair, HSG C
82 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ftlfl) (ftlsec) (cfs)
17.7 200 0.0250 0.2 Sheet Flow, SHEET FLOW
Grass: Short n= 0.150 P2= 2.50"
Runoff =
Subcatchment 2S: PROPOSED SITE
1.84 cfs @ 12.10 hrs, Volume=
0.119 af, Depth= 1.24"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 YEAR Rainfall=2.80"
Area (sf)
11 ,146
38,925
50,071
CN Description
100 IMPERVIOUS
79 50-75% Grass cover, Fair, HSG C
84 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ftlfl) (ftlsec) (cfs)
17.7 200 0.0250 0.2 Sheet Flow, SHEET
Grass: Short n= 0.150 P2= 2.50"
6444 MURRAY HILL
Prepared by Terra Engineering Inc.
HydroCAO@7.00 sin 001544 @ 1986-2003 Applied Microcomputer Systems
Type /I 24-hr 10 YEAR Rainfall=4.20"
Page 4
1 0/12/2007
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+ Trans method - Pond routing by Stor-Ind method
Subcatchment 1 S: EXISTING SITE
Runoff Area=50,071 sf Runoff Oepth=2.19"
Flow Length=200' Tc=17.7 min CN=82 Runoff=3.23 cfs 0.210 af
Subcatchment 2S: PROPOSED SITE
Runoff Area=50,071 sf Runoff Oepth=2.36"
Flow Length=200' Tc=17.7 min CN=84 Runoff=3.46 cfs 0.226 af
Total Runoff Area = 2.299 ac Runoff Volume = 0.436 af Average Runoff Depth = 2.27"
6444 MURRAY HILL
Prepared by Terra Engineering Inc.
HydroCAO@7.00 sIn 001544 @ 1986-2003 Applied Microcomputer Systems
Type /I 24-hr 10 YEAR Rainfal/=4.20"
Page 5
1 0/12/2007
Runoff
=
Subcatchment 1S: EXISTING SITE
3.23 cfs @ 12.10 hrs, Volume=
0.210 af, Depth= 2.19"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 YEAR Rainfall=4.20"
Area (sf)
6,646
43,425
50,071
CN Description
100 IMPERVIOUS
79 50-75% Grass cover, Fair, HSG C
82 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (fUft) (fUsee) (cfs)
17.7 200 0.0250 0.2 Sheet Flow, SHEET FLOW
Grass: Short n= 0.150 P2= 2.50"
Runoff
=
Subcatchment 2S: PROPOSED SITE
3.46 cfs @ 12.10 hrs, Volume=
0.226 af, Depth= 2.36"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 YEAR Rainfall=4.20"
Area (sf)
11 ,146
38,925
50,071
CN Description
100 IMPERVIOUS
79 50-75% Grass cover, Fair, HSG C
84 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (fUsee) (cfs)
17.7 200 0.0250 0.2 Sheet Flow, SHEET
Grass: Short n= 0.150 P2= 2.50"
6444 MURRAY HILL
Prepared by Terra Engineering Inc.
HydroCAD@ 7.00 sIn 001544 @ 1986-2003 Applied Microcomputer Systems
Type /I 24-hr 100 YEAR Rainfal/=6.00"
Page 6
1 0/12/2007
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+ Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: EXISTING SITE
Runoff Area=50,071 sf Runoff Depth=3.70"
Flow Length=200' Tc=17.7 min CN=82 Runoff=5.38 cfs 0.355 af
Subcatchment 2S: PROPOSED SITE
Runoff Area=50,071 sf Runoff Depth=3.91"
Flow Length=200' Tc=17.7 min CN=84 Runoff=5.62 cfs 0.374 af
Total Runoff Area = 2.299 ac Runoff Volume = 0.729 af Average Runoff Depth = 3.81"
6444 MURRAY HILL
Prepared by Terra Engineering Inc.
HydroCAD@ 7.00 sIn 001544 @ 1986-2003 Applied Microcomputer Systems
Type /I 24-hr 100 YEAR Rainfal/=6.00"
Page 7
1 0/12/2007
Runoff =
Subcatchment 1 S: EXISTING SITE
5.38 cfs @ 12.10 hrs, Volume=
0.355 af, Depth= 3.70"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 100 YEAR Rainfall=6.00"
Area (sf)
6,646
43,425
50,071
CN Description
100 IMPERVIOUS
79 50-75% Grass cover, Fair, HSG C
82 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/fl) (ft/sec) (cfs)
17.7 200 0.0250 0.2 Sheet Flow, SHEET FLOW
Grass: Short n= 0.150 P2= 2.50"
Runoff
=
Subcatchment 2S: PROPOSED SITE
5.62 cfs @ 12.10 hrs, Volume=
0.374 af, Depth= 3.91"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 100 YEAR Rainfall=6.00"
Area (sf)
11 ,146
38,925
50,071
CN Description
100 IMPERVIOUS
79 50-75% Grass cover, Fair, HSG C
84 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/fl) (ft/sec) (cfs)
17.7 200 0.0250 0.2 Sheet Flow, SHEET
Grass: Short n= 0.150 P2= 2.50"