SW8120209_COMPLIANCE_20120322

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
CO COMPLIANCE EVALUATION INSPECTION
l
DOC DATE
YYYYMMDD

SAND FILTER DESIGN Closed
FILENAME: S:IWQSlStormwaterlpermits & projects1YR1120209 HI)i mo excel_SF 120209
Initial Run Date:
8-Mar-12
Reviewer:
csb
Last modified:
22-Mar-12
Project Number SW8
120209
PROJECT NAME:
Center for Public
Safety
Sand Filter #
1
2
3
4
5
6
7
Receving Stream
New River
New River
New River
Now River
New River
Now River
New River
Classification
58.HQW,NSW
53,HQW;NSW
SB.HQW,NSW
SB,HQW,NSW
SB;HQW.NSW
SB,HQW;NSW
S3,HQW;NSW
Index Number
19-(10.5)
19-(10.5)
19-(10.5)
19-(10.5)
19-(10.5)
19-(10.5)
19-(10.5)
Onsite DA
47559
61263
56996
35806
24699
23740
9017 sf
Offsite DA
sf
Total DA
47559
61263
58998
35806
24699
23740
9017 sf
Total DA acres
1.09
1.41
1.35
0.82
0.57
0.54
0.21 ac.
Buildings
24002
19711
9017 sf
Parking/Street
14461
29666
37660
27748
20125
17293
sf
Concrete
3180
3296
1065
sf
Other
2413
sf
Offsite
sf
Total BUA
41643
55086
38725
27748
20125
17293
9017 sf
Runoff Cc
0.87
0.88
0.71
0.79
0,82
0.78
0.98
REQUIRED VOLUME CALCULATIONS
%impervious
87.56%
89.92%
65.64%
77.50%
81.48%
72.84%
100.00% %
Rv factor, pro
0.05
0.05
0.05
0.05
0,05
0.05
0.05 -77
Rv factor, post
0.838
0.859
0.641
0.747
0.783
0.706
0,950
Design Storm
1.50
1.500
1.500
1,500
1.500
1.S00
1.500 in
1.5" volume
4982
6580
4725
3345
2418
2094
1071 cf
1 yr24 hr precip depth
in
1 yr 24 hr pre vol
N/A
N/A
N/A
N/A
N/A
N/A
N/A cf
1 yr 24 hr post vol
N/A
N/A
N/A
N/A
N/A
N/A
N/A cf
Post - Pre
N/A
N/A
Ni
N/A
N/A
N/A
N/A cf
Total WQV
4982
6580
4725
3345
2418
2094
1071 cf
WQV to store
3737
4935
3544
2509
1814
1570
803 cf
REQUIRED SURFACE AREAS
Designer's hmax
2.50
2.53
2.50
2.50
2.56
2.50
2.50 ft
As+Afrequired
1495
1951
1418
1004
709
628
321 sf
Min. As
329
434
312
221
160
138
71 sf
Depth of Sand Bed
1.50
1.5
1.5
1.5
1.5
1.5
1.5 ft
Min. Af
468
614
444
314
225
197
101 sf
SURFACE AREAS &
VOLUME PROVIDED
CALCULATIONS
As provided
1082
1578
958
710
462
462
231 sf
Af provided
494
618
494
370
246
246
123 sf
As+Afprovided =
1576
2196
1452
1080
708
708
354 sf
Min. As+Af rov?
OK
OK
OK
OK
NO
OK
OK
Sed. Ch. Drain?
NO
Y or N
Weirelevation
11.08
10.1
11.15
12.38
12.4
10.53
10.44 fmsl
Bypass/Spillway
1358
12.63
13.65
14.98
14,96
13.03
12.94 fmsl
Top of Sand Elev.
11.08
10.1
11.15
12.38
12.4
10.53
10,44
Hmax provided
2.3709143
2.24729124
2.44075413
2.32322049
2,56189751
2.2180482
2.26857786
Hmax Met?
NO
NO
NO
NO
YES
NO
NO
Bottom of Sed. Ch.
9.58
8.6
9.65
10.88
109
9,03
8.94
Volume provided
2705
3992
2395
1775
1183
1155
578 of
Min. Vol. Prov?
NO
NO
NO
NO
NO
NO
NO
DRAWDOWN CALCULATIONS
1yr24hr storm intensity
in/hr
1y24 hr pre -peak flow
0
0
0
0
0
0
0 cfs
Orifice Diameter
4
4
4
4
4
4
4 in
Orifice Area
0,087
0.087
0.087
0.087
0.087
0.087
0.087 sf
Avg H on Orifice
2.17
2,19
2.17
2,17
2.21
2,17
2.17 ft
Min. 40 hour flowrate
0.03
0.0S
0.03
0.02
0.02
0.01
0.01 cfs
Orifice flow rate
0.542
0.546
0.542
0.542
&549
0.542
0.542 cfs
Time to drawdown
1.9
2.5
1.8
1.3
0.9
0.8
0.4 hrs