HomeMy WebLinkAboutWPO201800077 Calculations 2021-08-06OLD TRAIL VILLAGE
BLOCK 32 AMENDMENT
(WP0201800077)
COUNTY OF ALBEMARLE, VIRGINIA
DESIGN CALCULATIONS & NARRATIVE
JULY 19, 2021
•�0000
•
TIMMONS GROUP
YOUR VISION ACHIEVED THROUGH OURS.
Prepared by: Craig Kotarski, PE
Timmons Group
608 Preston Ave, Suite 200
Charlottesville, VA 22903
434.327.1688
3tMG W. I KOTARSK[
Lic. No. 0402048507
07-19-2021 ,<
APPROVED
by the Albemarle County
Communit Deve2pmentDepartment
Date 88 1
File WP0201800077-amendment 1
Table of Contents
Section Title
Project Narrative
2 LD 229 — Storm Sewer Design Computations
LD 204 — Storm Inlet Design Computations
4 LD 347 — Hydraulic Grade Line Computations
VRRM Spreadsheet Summary
6 HydroCAD Calculations
Project Narrative:
This project includes the revised calculations for the development within Block 32 known
as the site plan for lots 34-40, prepared by Kirk Hughes & Associates. The original
impervious footprint has been altered and slightly increased since the original approval of
WPO201800077. The calculations herein reflect the as -built conditions of the storm
sewer system and shall supersede the approved calculations shown on WPO201800077 &
SUB201800164.
Stormwater Management:
Old Trail Village adheres to a Master Stormwater Management Plan WPO201600009
prepared by Stantec and approved by the County of Albemarle on April 25, 2016. The
master plan outlines the pre and post development areas allocated to existing onsite
stormwater management facilities and guidance for the future construction of onsite
facilities. References to the master plan are provided with the submittal of each new
development area and accompanied with an overall tracking compliance spreadsheet.
Additional parameters or amendments are submitted on an as -needed basis and
information provided at the time of the stormwater facility design.
STM B
STORM SEWER DESIGN COMPUTATIONS
STORM FREQUENCY 10
PROJECT: Block 32 KHA Amednment
LOCATION:
COUNTY: Albemarle
Designed by: JLF
Checked by: CJK
UNITS ENGLISH
7/19/2021
PIPE
NO
FROM POINT
TO POINT
DRAIN.
AREA
"A"
Acre
(3)
RUNOFF
COEFF.
"C"
(4)
CA
TOTAL
INLET
TIME
Minutes
(7)
RAIN
FALL
In/Hr
(8)
RUNOFF
Q
CFS
(9)
INVERT ELEVATIONS
LENGTH
of Pipe
Ft.
(12)
SLOPE
Ft./Ft.
(13)
SIZE
(Dia. Or
Span/Rise)
In.
(14)
SHAPE
Capacity
CFS
(15)
Friction
Slope
Ft./Ft.
VEL
Vn
Ft/Sec
(16)
FLOW
TIME
Min.
(17)
REMARKS
(18)
7(5(67
ADDTL
CA
UPPER
END
(10)
LOWER
END
(11)
REFERENCE
(1)
STA.
REFERENCE
(2)
STA.
STR(3)
STR 11B
STR IOB
0.870
0.700
0.609
0.609
0.000
5.000
6.542
3.984
687.000
683.990
59.327
0.051
15.000
Circular
18.910
0.002
12.235
0.081
STR (6)
STR IOB
STR 9B
0.230
0.800
0.184
0.793
0.000
5.081
6.516
5.167
683.970
683.750
24.471
0.009
15.000
Circular
7.960
0.004
6.919
0.059
STR(8)
SIR9B
SIRSB
0.480
0.600
0.288
1.081
0.000
5.140
6.496
7.023
683.660
680.610
165.521
0.018
18.000
Circular
18.533
0.003
9.784
0.282
STR (53)
STR 8.211
STR 8.111
0.290
0.700
0.203
0.203
0.000
0.000
8.901
1.807
685.970
681.310
68.114
0.068
15.000
Circular
21.959
0.000
10.829
0.105
STR (54)
STR 8.113
SIR 8B
0.240
0.700
0.168
0.371
0.000
0.105
8.831
3.276
681.200
680.960
25.568
0.009
15.000
Circular
8.134
0.002
6.284
0.068
STR (10)
SIR 8B
SIR 713
0.190
0.650
0.124
1.576
0.000
5.422
6.406
10.093
680.230
674.540
157.510
0.036
24.000
Circular
55.889
0.001
13.521
0.194
STR (47)
STR 7.211
STR 7.1B
0.460
0.700
0.322
0.322
0.000
0.000
8.901
2.866
677.270
675.630
83.258
0.020
15.000
Circular
11.783
0.001
7.938
0.175
SIR (50)
STR 7.111
SIR 7B
0.200
0.800
0.160
0.482
0.000
0.175
8.784
4.234
675.580
675.120
24.903
0.018
15.000
Circular
11.410
0.003
8.626
0.048
STR (12)
SIR 7B
SIR 6B
0.300
0.650
0.195
2.253
0.000
5.616
6.346
14.294
674.490
666.430
162.816
0.050
24.000
Circular
65.426
0.002
16.705
0.162
STR (58)
STR 6.211
STR 6.111
0.450
0.700
0.315
0.315
0.000
0.000
8.901
2.804
673.720
667.730
89.971
0.067
15.000
Circular
21.662
0.001
12.193
0.123
STR (56)
STR 6.111
STR 6B
0.130
0.800
0.104
0.419
0.000
0.123
8.819
3.695
667.720
666.820
25.537
0.035
15.000
Circular
15.761
0.002
10.508
0.041
STR (14)
SIR 6B
SIR 5B
0.260
0.650
0.169
2.841
0.000
5.778
6.296
17.885
666.390
661.380
117.803
0.043
24.000
Circular
60.641
0.004
16.829
0.117
STR(16)
SIRSB
SIR4B
0.180
0.650
0.117
2.958
0.000
5.895
6.261
18.518
660.580
650.650
95.142
0.104
36.000
Circular
280.124
0.000
22.478
0.071
STR (61)
STR 4.311
STR 4.213
0.320
0.650
0.208
0.208
0.000
0.000
8.901
1.851
657.080
654.620
26.871
0.092
15.000
Circular
25.402
0.000
12.087
0.037
SIR (63)
SIR 4.211
STR 4.113
0.400
0.450
0.180
0.388
0.000
0.037
8.876
3.444
654.330
653.490
46.431
0.018
24.000
Circular
39.551
0.000
7.746
0.100
STR (64)
STR 4.111
SIR 4B
0.660
0.450
0.297
0.685
0.000
0.137
8.809
6.034
652.950
650.650
23.900
0.096
36.000
Circular
268.983
0.000
15.629
0.025
STR(18)
SIR4B
SIR3B
0.170
0.650
0.111
3.753
0.000
5.966
6.240
23.420
650.540
649.140
76.796
0.018
36.000
Circular
117.073
0.001
12.9571
0.099
STR (20)
SIR 3B
STR 2B
0.140
0.800
0.112
3.865
0.000
6.064
6.211
24.006
649.010
647.390
24.425
0.066
36.000
Circular
223.309
0.001
20.671
0.020
STR(22)
SIR2B
STR1B
0.190
0.650
0.124
3.989
0.000
6.084
6.205
24.750
647.110
646.830
68.746
0.004
36.000
Circular
55.337
0.001
7.626
0.150
STR (24)
SIR 1B
STR OB
0.000
0.000
0.000
3.989
0.000
6.234
6.162
24.577
646.730
646.410
21.922
0.015
36.000
Circular
104.761
0.001
12.1261
0.030
FORM LD 204 STORMWATER INLET COMPUTATIONS SHEET 1 OF 3
ROUTE
PROJECT Block 32 KHA Ammendment
DESIGNER: JLF
CHECKED: CJK
DATE 7/19/2021
UNITS ENGLISH
INLET
Z
^.
U
w
>.i
08
k�
x�
�v�
09
y�
q
3�v
{a��
y
�"
OZ
^w
F
P
ab
o}�,
"
2
Sag
Inlets
Only
K
ZP4
F
a°'(✓
v
Ua
IOB
DI-2A
4.2
0.870
0.80
0.696
WRIGHT
0.696
4
2.784
0
2.784
0.0500
0.0208
5.902
2.000
0.3389
0.0833
4.0048
0.824
3.50
0.1458
0.1409
15.122
2.200
0.278
0.443
1.234
1.550
2.973
11B
DI-2C
8.000
0.870
0.80
0.696
Bnk/Lt.
0.0001RIGHT
0.696
4
2.784
0
0.0150
0.0208
8.156
2.000
0.2452
0.0833
4.0048
3.50
Bnk/Lt.
0
4
0
0
Ahead/Rt.
2.784
0.0150
2.000
8
2.784
5A88
0.166
0.500
0.332
7.613
21.989
T> 8.0 ft
2B
DI-2B
8
0.190
0.65
0.1235
WRIGHT
0.124
4
0.496
0.079
0.575
0.0500
0.0208
1.738
2.000
1.1507
0.0833
4.0048
1.000
3.50
0.1458
0.1666
7.050
6.000
L135
1.000
0.575
0.000
1.737
3B
DI-2B
8
0.140
0.80
0.112
WRIGHT
0.112
4
0.448
0.064
0.512
0.0500
0.0208
1.664
2.000
1.2019
0.0833
4.0048
1.000
3.50
0.1458
0.1666
6.715
6.000
L 191
1.000
0.512
0.000
1.663
4.IB
DI-2C
6.000
0.660
0.45
0.297
Bnk/Lt.
0.0001RIGHT
0.297
4
1.188
0.119
0.0500
0.0208
3.390
2.000
0.59
0.0833
4.0048
3.50
Bnk/Lt.
0
4
0
0
Ahead/Rt.
1.307
0.0500
2.000
6
1.307
2.088
0.166
0.500
0.332
4.213
8.367
T > 8.0 ft
4.2B
DI-2B
6
0.400
0.45
0.18
WRIGHT
0.18
4
0.72
0
0.720
0.0500
0.0208
1.890
2.000
1.0582
0.0833
4.0048
1.000
3.50
0.1458
0.1666
7.748
4.000
0.774
0.931
0.671
0.049
1.889
4.3B
DI-2B
6
0.320
0.65
0.208
WRIGHT
0.208
4
0.832
0
0.832
0.0500
0.0208
1.995
2.000
1.0025
0.0833
4.0048
1.000
3.50
0.1458
0.1666
8.233
4.000
0.729
0.904
0.753
0.079
1.995
4B
DI-2A
4.2
0.170
0.65
0.1105
WRIGHT
0.111
4
0.444
0.004
0.448
0.0500
0.0208
1.582
2.000
1.2642
0.0833
4.0048
1.000
3.50
0.1458
0.1666
6.348
2.200
0.662
0.858
0.384
0.064
1.582
5B
DI-2B
6
0.180
0.65
0.117
WRIGHT
0.117
4
0.468
0
0.468
0.0500
0.0208
1.609
2.000
1.243
0.0833
4.0048
1.000
3.50
0.1458
0.1666
6.466
4.000
0.928
0.991
0.464
0.004
1.608
6.IB
DI-2A
4.2
0.130
0.80
0.104
INLETSOFT BY ENSOFTEC DATE: 7/19/2021
FORM LD 204 STORMWATER INLET COMPUTATIONS SHEET 2OF 3
ROUTE
PROJECT Block 32 KHA Ammendment
DESIGNER: JLF
CHECKED: CJK
DATE 7/19/2021
UNITS ENGLISH
INLET
Z
F
^.
o
za
o
a
"
U
w
xµ
>.i
o�
k�
x�
�v�
09
y�
3
a�
y
�"
0
^w
F
a
off,
.�
Sag
Inlets
Only
rL
F
a°°'(✓
v
Ua
O'RIGHT
0. 104
4
0.416
0
0.416
0.0100
0.0208
2.321
2.000
0.8617
0.0833
4.0048
0.999
3.50
0.1458
0.1665
3.799
2.200
1.106
1.000
0.416
0.000
2.079
6.2B
DI-2C
6.000
0 450
0.70
0.315
Buk/Lt.
0.0001RIGHT
0.315
4
1.26
0
0.0150
0.0208
5.243
2.000
0.3815
0.0833
4.0048
3.50
Bwk/Lt.
0
4
0
0.14
Ahead/Rt.
1.400
0.0150
2.000
6
1.400
3.471
0.166
0.500
0.332
5.596
13.905
T > 8.0 ft
6B
DI-2C
6.000
0.260
0.65
0.169
Bwk/Lt.
0.0001RIGHT
0.169
4
0.676
0.245
0.0150
0.0208
4.203
2.000
0.4759
0.0833
4.0048
3.50
Bxk/Lt.
0
4
0
0
Ahead/Rt.
0.921
0.0150
2.000
6
0.921
2.625
0.166
0.500
0.332
4.750
10.518
T > 8.0 ft
TIB
DI-2A
4.2
0.200
0.80
0.16
O'RIGHT
0.16
4
0.64
0
0.640
0.0500
0.0208
1.809
2.000
1.1056
0.0833
4.0048
1.000
3.50
0.1458
0.1666
7.374
2.200
0.570
0.781
0.500
0.140
1.808
7.2B
DI-2C
6.000
0.460
0.70
0.322
Bnk/Lt.
0.0001RIGHT
0.322
4
1.288
0
0.0150
0.0208
5.319
2.000
0.376
0.0833
4.0048
3.50
Bnk/Lt.
0
4
0
0.155
Ahead/Rt.
1.443
0.0150
2.000
6
1.443
2.231
0.166
0.500
0.332
4.356
8.938
T> 8.0 ft
7B
DI-2A
4.2
0.300
0.65
0.195
WRIGHT
0.195
4
0.78
0.081
0.861
0.0500
0.0208
2.085
2.000
0.9592
0.0833
4.0048
1.000
3.50
0.1458
0.1666
8.353
2.200
0.503
0.716
0.616
0.245
2.020
8.1B
DI-2A
4.2
0.240
0.70
0.168
WRIGHT
0.168
4
0.672
0
0.672
0.0500
0.0208
1.842
2.000
1.0858
0.0833
4.0048
1.000
3.50
0.1458
0.1666
7.527
2.200
0.558
0.770
0.517
0.155
1.841
8.2B
DI-2C
6.000
0.290
0.70
0.203
Bnk/Lt.
0.0001RIGHT
0.203
4
0.812
0
Bnk/Lt.
0
4
0
1.55
0.0150
0.0208
5.959
2.000
0.3356
0.0833
4.0048
3.50
Ahead/Rt.
2.362
0.0150
2.000
6
2.362
3.099
0.166
0.333
0.4985
5.224
12.414
T > 8.0 ft
8B
DI-2A
4.2
0.190
0.65
0.1235
O'RIGHT
0. 124
4
0.496
0 403
0.899
0.0500
0.0208
L644
2.000
1.2165
0.0833
4.0048
1.000
3.50
0.1458
0.1666
6.626
2.200
0.634
0.836
0.415
0.081
L643
INLETSOFT BY ENSOFTEC DATE: 7/19/2021
FORM LD 204 STORMWATER INLET COMPUTATIONS SHEET 3 OF 3
ROUTE
PROJECT Block 32 KHA Ammendment
DESIGNER: JLF
CHECKED: CJK
DATE 7/19/2021
UNITS ENGLISH
INLET
U
>.i
Sag
Inlets
Only
K
F
Z
^.
w
08
k�
x�
�v�
09
3�v
y
�"
^w
F
P
o}�,
a°'(✓
v
Ua
y�
q
{a��
"
2
ZP4
OZ
9B
DI-2A
4.2
0 480
0.60
0.288
WRIGHT
1 0.288
4
1.152
0
1.152
0.0500
0.0208
2.990
2.000
0.6689
0.0833
4.0048
0.989
3.50
0.1458
0.1650
9.494
2.200
0.442
0.651
0.749
0.403
2.246
INLETSOFT BY ENSOFTEC DATE: 7/19/2021
LD-347 PROJECT: Block 32 KHA Amentlmenl DESIGNED BY: JLF
HYDRAULIC GRADE LINE ANALYSIS
Checked: CJK
10 Yw
INLET
OR
JUNCTION
STA.
INVERT
EL.
WTFLOW
PIPE
DEPTH
OF FLOW
OUTFL
PIPE
OUTLET
WATER
SURFACE
ELF/.
OIA
PIPE
D.
INmm
DESIGN
TISCH.
Go
CFS/CMS
kENGTH
PIPE
Ln
(FM)
FRICTION
SLOPEM
(FT/FT)
MRA
FRICTION
LOSS
H!
FLM
JUNCTION
LOSS
SURFACE
FLOW
Mj HI
13
H,
FLM
InW
Shaq�gi
YIN
0.5
H,
FLM
FINAL
H
F,RA
Ink,
N2kr
Surte¢
Elevation
Top oI MH
Top IXlnk,
Flow
APPRO%.
Pilµs,mTlT
Vo
Cmtr.
No
FtlM
Yi
Mi ,
Hi (Expn)
035'MA%.
SKEW
A,6
K
Pap
H
FNA
Si-
HL
FLM
(1)
2
(3)
(4)
5)
(6)
(n
(8)
9)
(10)
(11)
12
(13)
14)
15)
16)
16)
(17)
(18)
(19
OB
649.410
1B
646.410
3.00
649.410
36
0.811
21.92
0.00000
0.000
3.880
0.058
3.016
0.141
0.049
0.0
0.00
0.000
0.108
0.000
0.108
YES
0.054
0.0&1
849.484
652.940
O.K.
2B
646.830
3.00
649.1
36
1.544
68.75
0.00000
0.000
3.016
0.035
7.851
0.957
0.335
0.0
0.00
0.000
0.370
0.811
0.481
YES
0.241
0.241
649.705
657.880
O.K.
3B
647.390
3.00
649.790
36
1.459
24.43
0.00000
0.000
7.851
0.239
6.462
0.648
0.227
0.0
0.00
0.000
0.466
0.733
0.606
YES
0.303
0.303
650.093
657.580
O.K.
4B
649.140
3.00
651.540
36
3.409
76.80
0.00002
0.002
6.462
0.162
12.554
2.447
0.857
0.0
0.00
0.000
1.019
0.719
1.324
YES
0.662
DAU
652.204
664.150
O.K.
5B
650.650
1.50
652.204
18
1.871
95.14
0.00028
0.027
10.896
0.461
14.963
3.4n
1.217
0.0
0.00
0.000
1.678
0.765
2.181
YES
1.090
1.117
660.810
669.270
O.K.
BB
661.380
1.50
662.580
18
20.444
117.80
0.03374
3.974
14.963
0.869
15.721
3.838
1.343
0.0
0.00
0.000
2.212
1.106
2.212
YES
1.106
5.081
667.661
676.240
O.K.
7B
666.430
2.00
668.030
24
18A58
162.82
0.00606
0.986
15.721
0.959
13.024
2.634
0.922
0.0
0.00
0.000
1.881
1.276
1.881
YES
0.941
1.927
675.297
684.060
O.K.
8B
674.540
2.00
676.140
24
14.229
157.51
0.00352
0.555
13.024
0.658
9.492
1.399
0.490
0.0
0.00
0.000
1.148
0.811
1.148
YES
0.574
1.129
680.988
689.220
O.K.
9B
680.610
1.50
681.810
18
10.991
165.52
0.00975
1.614
9.492
0.350
7.420
0.855
0.299
0.0
0.00
0.000
0.649
1.884
0.649
YES
0.324
1.939
684.595
692.600
O.K.
10B
683.750
1.25
685.000
15
9.106
24.47
0.01770
0.433
9.420
0.214
11.111
1.917
0.671
0.0
0.00
0.000
0.885
4.553
1.150
YES
0.575
1.008
686.008
692.630
O.K.
11B
683.990
1.25
686.008
15
4.553
59.33
0.00442
0.263
11.111
0.479
0.000
0.000
0.000
0.0
0.00
0.000
0.479
4.553
0.623
YES
0.312
O.S74
687.460
694.030
O.K.
4.113
650.650
3.00
653.050
36
4.481
23.90
0.00004
0.001
12.554
0.612
6.215
0.600
0.210
0.0
0.00
0.000
0.822
1.943
1.068
YES
0.534
0.535
653.585
664.250
O.K.
4.213
653.490
2.00
655.090
24
2.538
46.43
0.00011
DODS
6.215
0.150
9.687
1.457
0.510
0.0
0.00
0.000
0.660
1.178
0.858
YES
0.429
OAU
655.524
664.760
O.K.
4.313
654.620
1.25
655.620
15
1.361
26.87
0.00040
0.011
9.687
0.364
0.000
0.000
0.000
0.0
0.00
0.000
0.364
1.361
0.474
YES
0.237
0.247
657.295
663.840
O.K.
6.1B
666.820
1.50
668.020
18
2.741
25.53
0.00061
0.015
8.313
0.268
9.574
1.423
0.498
0.0
0.00
0.000
0.766
0.680
0.996
YES
OA98
0.514
668.534
676.520
O.K.
6.2B
667.730
1.50
668.930
18
2.061
89.97
0.OD034
0.031
9.574
0.356
0.0D0
0.000
0.000
0.0
0.00
0.000
0.356
2.061
0.463
YES
0.231
0.262
673.989
679.960
O.K.
Zi6
675.120
1.25
676.120
15
3.153
24.90
0.OD212
0.053
6.962
0.188
6.266
0.610
0.213
0.0
0.00
0.000
0.402
1.047
0.522
YES
0.261
0.314
6T6.434
684.250
O.K.
].2B
675.630
1.50
676.830
18
2.107
83.25
0.00036
0.030
6.266
0.152
0.0D0
0.000
0.000
0.0
0.00
0.000
0.152
2.107
0.198
YES
0.099
OA29
677.638
687.280
O.K.
8.1B
880.980
1.25
681.960
15
2.420
25.57
0.00125
0.032
5.064
0.100
8.680
1.170
0./09
0.0
0.00
0.000
0.509
1.092
0.662
YES
0.331
0.363
682.323
689.320
O.K.
8.2B
681.310
1.25
682.323
15
1.328
68.11
0.OD038
0.026
8.680
0.292
0.000
0.000
0.000
0.0
0.0
00.000
0.292
1.328
0.380
YES
OA90
0.216
686.198
691.380
O.K.
12S
5S
Pre -Developed
Post -Developed
(Detained)
7P
Detention and
11L
DA Post Total
Subcat Reach On Link Routing Diagram for Block 32 Amendment
Prepared by Timmons Group, Printed 7/15/2021
FHydroCADO 10.10-4a s/n 08663 0 2020 HydroCAD Software Solutions LLC
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 2-Year Rainfall=3.30"
Printed 7/15/2021
Summary for Subcatchment 5S: Post -Developed (Detained)
[491 Hint: Tc<2dt may require smaller dt
Runoff = 17.89 cfs @ 11.96 hrs, Volume= 0.834 af, Depth> 1.48"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr 2-Year Rainfall=3.30"
Area (ac) CN Description
3.530
98 Paved roads w/curbs & sewers, HSG B
3.240
61 >75% Grass cover, Good, HSG B
6.770
80 Weighted Average
3.240
47.86% Pervious Area
3.530
52.14% Impervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
2.0
100
1.0000
0.84
Sheet Flow,
Grass: Short n= 0.150 P2= 3.38"
2.9
150
0.0150
0.86
Shallow Concentrated Flow,
Short Grass Pasture Kv= 7.0 fps
0.3
240
0.0200
14.46
102.19 Pipe Channel,
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.012 Corruqated PP, smooth interior
5.2 490 Total
Subcatchment 5S: Post -Developed (Detained)
Hydrograph
20
19
I I I
r__i _II__i__ 7__ r__II
r__r_ -__ -- 7__ r__ r__ r__1___1_`'
17
1 I I I 1
16
1 1 1
1
15
1 I I 1 1 I I I I
1 1 1
14
13
,
12
1 1 1 1
__L__I__J__J__1__1__L__L__I__J_.
1 I I 1 1 I I I I 1
L__L__I__ J_.
...
i I
-I -I
G
9
, 1 1 I
LL
_� _y _i _I
I 1
I
5
1
-r--__ _ __1__ _I___I
1---*--r--r
4
- - r--I-
T--1--
3
-r_r_r --
2
__1_____._ 1
_lT__r__r-
1 1 r
1
Type II 24-hr
2-Year Rainfall=3.30"
Runoff Area=6.770 ac
R4npff111Vplume=110.034 Of
---Runoff Depth>1.48"
Flow Lenoth=490'
Tc=5.2 ruin
CN=8O -Y
1
0 1 2 3 4 5 6 7 B 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
❑ Runoff
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 2-Year Rainfall=3.30"
Printed 7/15/2021
Summary for Subcatchment 12S: Pre -Developed
Runoff = 14.40 cfs @ 12.07 hrs, Volume= 0.910 af, Depth> 1.61"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr 2-Year Rainfall=3.30"
Area (ac) CN Description
6.770 82 Approved Existing CN
6.770 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
14.3 Direct Entry,
Subcatchment 12S: Pre -Developed
Hydrograph
Type II 24-hr
-2-Year Rainfall=3.30rr
;; -Runoff Area=6.770 ac
_Runoff Volume=0.910 of
9 , Runoff Depth>1.61"
ME Tc=14.3 min
-------
I I I
I I I
I I I
I--�--�--�-- ■Runoff
1 I
L__I__J__J__1__1__L__L__
I I I I I I I I I
--r--r--Ir
I 1 I I I I I
I I I I 1 1 I I I I
---------------------------------
I I I I I I I I I I
I I I I I I I I I I I
I I I I I I I I I I I
I I I I I I I I I
I I I I I
I I I I I I I I I I I
I I I I I I I I I
I I I I I I I I I I
---------------- -- ---- --
I I I I I I I I
I I I I I I I I I I
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 2-Year Rainfall=3.30"
Printed 7/15/2021
Summary for Pond 7P: Detention Pond
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 1.48" for 2-Year event
Inflow = 17.89 cfs @ 11.96 hrs, Volume= 0.834 of
Outflow = 4.39 cfs @ 12.12 hrs, Volume= 0.831 af, Atten= 75%, Lag= 9.2 min
Primary = 4.39 cfs @ 12.12 hrs, Volume= 0.831 of
Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Peak Elev= 649.39' @ 12.12 hrs Surf.Area= 3,065 sf Storage= 10,120 cf
Plug -Flow detention time=17.4 min calculated for 0.829 of (99% of inflow)
Center -of -Mass det. time= 15.5 min ( 852.0 - 836.5 )
Volume Invert
Avail.Storage Storage Description
#1 642.00'
46,174
cf Custom Stage Data (Irregular)Listed below (Recalc)
Elevation Surf.Area
Perim. Inc.Store Cum.Store Wet.Area
(feet)
(sq-ft)
(feet) (cubic -feet) (cubic -feet) (sq-ft)
642.00
195
549.0 0 0 195
644.00
661
30.0 810 810 24,115
646.00
1,361
75.0 1,980 2,790 24,506
648.00
2,296
116.0 3,616 6,407 25,157
650.00
3,438
152.0 5,696 12,103 25,970
652.00
4,818
190.0 8,217 20,320 27,060
654.00
6,426
232.0 11,205 31,525 28,532
656.00
8,261
266.0 14,649 46,174 29,968
Device Routing
Invert
Outlet Devices
#1 Primary
642.00'
36.0" Round Culvert
L= 105.0' CPP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 642.00' / 640.00' S= 0.0190 '/' Cc= 0.900
n= 0.012 Corrugated PP, smooth interior, Flow Area= 7.07 sf
#2 Device 1
642.25'
8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1
651.00'
60.0" Horiz. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#4 Primary
653.00'
25.0' long x 30.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=4.38 cfs @ 12.12 hrs HW=649.37' (Free Discharge)
1=Culvert (Passes 4.38 cfs of 65.10 cfs potential flow)
�2=Orifice/Grate (Orifice Controls 4.38 cfs @ 12.54 fps)
3=Orif ice/G rate ( Controls 0.00 cfs)
= B road-C rested Rectangular Weir( Controls 0.00 cfs)
Block 32 Amendment
Prepared by Timmons Gi
Type 1124-hr 2-Year Rainfall=3.30"
Pond 712: Detention Pond
Hydrograph
---- -- --------- --Y-- ---------
Printed 7/15/2021
/
I I I I 1
r I 1 4__ r__r_- I __ __-__r__r__r_-__7r_--- _-__7__r__r__1__
2,0
--11 -- ---I ---a- i--
1 I -I _
j 1I I 1 I Il1 I
=1nfi1owiAa671W
c18 =
__L__1__
'
-27
16
15
__--r--r- /�E
14
YI
_
7 _
13
12
1 1 1
„
p
i'
_J _J _1 _L _I _J _J _L _I _J _L_L__1__J__1__L_J__J__1__L__L_
10
1 1 1 1 1 1 1 1
0 9
1 1 1 1 1 1 1 1 1
a
i
'
_1 -y -Y -r -1 -1 -T -Y -1 _---y -r _1 -7 -T -r -1 _J -Y -r -r -1
7
'
1 1 1
1 1 1 1 1 1
__1__r__7__rr__r__r_�__r__r__r_r__r__r_7__r__1__1__
1-�--7--r--r--I--�--r--r------r--r-�--T--r--I--�--7--r--r--1--
5
4
3
4 5 6 7 8 9 10
Time (hours)
Pond 7P: Detention Pond
Stage -Discharge
Discharge (cfs)
■ Inflow
■ Primary
■ Primary
Block 32 Amendment
Prepared by Timmons Gi
Type 1124-hr 2-Year Rainfall=3.30"
Printed 7/15/2021
Pond 7P: Detention Pond
Stage -Area -Storage
Surface/Horizontal :ed Area (sq-ft)
0
500
1,000
1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 6,500 7,000 7,500 8,000
■ Surface
I
I I I II I u I I I I I
■ Storage
656
u u
,
1
_______
1 1 1 11 1 u 1 1 1 1 u
654
1
1 1
1 1 1
1 1 1 11 1 1 1 1 1 1 1 u
653
1
1
11
1 1 1
1 1 1
1 1 1 11 II 1 1 1 1 1 1 1 1 u
1 1 1 1 1 1 1 1 1 1 1 1 1 u
652
1
1 11 u 1 1 1 1 1 1 1 1 1 u
651
1
1 1
1 1 1
1 1 1 1 11 1 1 1 1 1 1 1 1 1 11
ar ''
650
1
-r--rr---r
11
1
rr_
1
1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
___R___
1 11 1 u 1 1 1 1 1 1 1 1 1 u
c 0 649 ,
1
1
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
i 648
11
1
____1____I____1____II_______I_1____I__1__I____I_1___I___ I1_
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
N
11
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
W
647 ,
--r--rr--
1
r-r-r---rr-1----n---1---rr---l--rr---r-r-r--r-r--1---rr
1 1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
,
L_1_L___L1__1____1J___L__JL__
646
I
I I I
I I I II I II I I I I I I I I I II
III II
645
r-r---rr--r---nI---r--rr---1--�
1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
644
1
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
643
Custom Stage
Data
,
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 2-Year Rainfall=3.30"
Printed 7/15/2021
Summary for Link 11 L: DA Post Total
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 1.47" for 2-Year event
Inflow = 4.39 cfs @ 12.12 hrs, Volume= 0.831 of
Primary = 4.39 cfs @ 12.12 hrs, Volume= 0.831 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Link 11 L: DA Post Total
Hydrograph
❑ Inflow
❑ Primary
Time (hours)
Block 32 Amendment
Prepared by Timmons Gi
Type II 24-hr 10-Year Rainfall=4.99"
Printed 7/15/2021
Summary for Subcatchment 5S: Post -Developed (Detained)
[491 Hint: Tc<2dt may require smaller dt
Runoff = 34.46 cfs @ 11.96 hrs, Volume= 1.626 af, Depth> 2.88"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-Year Rainfall=4.99"
Area (ac) CN Description
3.530
98 Paved roads w/curbs & sewers, HSG B
3.240
61 >75% Grass cover, Good, HSG B
6.770
80 Weighted Average
3.240
47.86% Pervious Area
3.530
52.14% Impervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
2.0
100
1.0000
0.84
Sheet Flow,
Grass: Short n= 0.150 P2= 3.38"
2.9
150
0.0150
0.86
Shallow Concentrated Flow,
Short Grass Pasture Kv= 7.0 fps
0.3
240
0.0200
14.46
102.19 Pipe Channel,
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.012 Corruqated PP, smooth interior
5.2 490 Total
N 2
2
0 1
LL
Subcatchment 5S: Post -Developed (Detained)
Hydrograph
I I I
I I I
I I I I I I I I
I I I
----------------------------
I I I I I I I
I I I I I I I I
I I I I
I I I I I I
I I I I I
I I I I I I
I I I I I I
I I I I I I I I
I I I
I I I I I I I I
I I I I I I I I
I I I I I I I I
I I I I I I I I
I I I I I I I I I
I I I I I I I I I
I I I I I I I I I
I I
I I I I I I
I � I
I
I I I I
--r--I-----r-r--r--r--r--I---I---I
--r---- --- -----------
Type II 24-hr
10-Year Rainfall=4.99"
Runoff Area=6.770 ac
Runoff 'll-V-Plume-='11.026-elf -
Runoff Depth>Z.'88'--
r r _ flow Lencoth=490'
r r Ir Ir Tc= 5:;2 rn i In
I I I I
N=B� I I
I I I I I I I
----
r--r--r--r--r —I i--T--r--r--
I I I I I I I I I I
----r--r--r--r--I---I--� I I I
0 1 2 3 4 5 6 7 S 9 10 11 12 13
Time (hours)
19 20 21 22 23 24
❑ Runoff
Block 32 Amendment
Prepared by Timmons Gi
Type II 24-hr 10-Year Rainfall=4.99"
Printed 7/15/2021
Summary for Subcatchment 12S: Pre -Developed
Runoff = 27.18 cfs @ 12.06 hrs, Volume= 1.727 af, Depth> 3.06"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-Year Rainfall=4.99"
Area (ac) CN Description
6.770 82 Approved Existing CN
6.770 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
14.3 Direct Entry,
Subcatchment 12S: Pre -Developed
Hydrograph
26
Type II 24-hr
24
10-Year Rainfall=4.99"
22
Runoff Area=6.770 ac
18
Runoff Volume=1.727 of
16
Runoff Depth>3.06"
14
Tc=14.3 min -----'
LL
12
CN=8g ----r--'I
10
I I I
8
6
I I I
I I I I I I I I I
4
r __r__r__I___I__�__�__r__r__r__
■ RunoiF
I I I I I I I I I
I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I
----------------------------------
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
- r--r--r--r--I--�--�--r--r--r--
I I I I I I I I I I
I I I I I I I I I I I
y__r__r__r__
1__L__L__
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
Block 32 Amendment
Prepared by Timmons Gi
Type II 24-hr 10-Year Rainfall=4.99"
Printed 7/15/2021
Summary for Pond 7P: Detention Pond
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 2.88" for 10-Year event
Inflow = 34.46 cfs @ 11.96 hrs, Volume= 1.626 of
Outflow = 24.51 cfs @ 12.04 hrs, Volume= 1.622 af, Atten= 29%, Lag= 4.6 min
Primary = 24.51 cfs @ 12.04 hrs, Volume= 1.622 of
Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Peak Elev= 651.53' @ 12.04 hrs Surf.Area= 4,470 sf Storage= 18,119 cf
Plug -Flow detention time= 21.7 min calculated for 1.622 of (100% of inflow)
Center -of -Mass det. time= 20.5 min ( 837.9 - 817.5 )
Volume Invert
Avail.Storage Storage Description
#1 642.00'
46,174
cf Custom Stage Data (Irregular)Listed below (Recalc)
Elevation Surf.Area
Perim. Inc.Store Cum.Store Wet.Area
(feet)
(sq-ft)
(feet) (cubic -feet) (cubic -feet) (sq-ft)
642.00
195
549.0 0 0 195
644.00
661
30.0 810 810 24,115
646.00
1,361
75.0 1,980 2,790 24,506
648.00
2,296
116.0 3,616 6,407 25,157
650.00
3,438
152.0 5,696 12,103 25,970
652.00
4,818
190.0 8,217 20,320 27,060
654.00
6,426
232.0 11,205 31,525 28,532
656.00
8,261
266.0 14,649 46,174 29,968
Device Routing
Invert
Outlet Devices
#1 Primary
642.00'
36.0" Round Culvert
L= 105.0' CPP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 642.00' / 640.00' S= 0.0190 '/' Cc= 0.900
n= 0.012 Corrugated PP, smooth interior, Flow Area= 7.07 sf
#2 Device 1
642.25'
8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1
651.00'
60.0" Horiz. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#4 Primary
653.00'
25.0' long x 30.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=22.99 cfs @ 12.04 hrs HW=651.50' (Free Discharge)
1=Culvert (Passes 22.99 cfs of 75.98 cfs potential flow)
�2=Orifice/Grate (Orifice Controls 5.02 cfs @ 14.38 fps)
3=Orif ice/G rate (Weir Controls 17.97 cfs @ 2.30 fps)
= B road-C rested Rectangular Weir( Controls 0.00 cfs)
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 10-Year Rainfall=4.99"
Printed 7/15/2021
Pond 712: Detention Pond
Hydrograph
___J____i__ i__i ______ i_____iii_------- _________I__ i_i ___ i_i _i __
J _1 _L _J _L -I-_J __
_L _I _J _1 _L _I _J _1 _L _L _I
■Inflow
38
' '
■Pnmary
.'
IJ1LIIJLIJ_ 3M1AB Cfe IJ1_/�_LIJ1yL
36
/_�_LI
-�flowt/'ire' 16.77a1,atr
34
,.
,
V
_ +__F__I__J
32
, �
30
,
yy__t__r____
28
,.'/
toragq-18 4 9-/�f
--I -i -
r- V1v' i/✓G
16`
,
2651 cfs
_ __r__r__r__I__�__r__r__r__I__
24
�'
4__r__r__I.
.
_ __r__� _r__7__r__I__�__7__r__r__I__
22
'
1 1 I 1 1 I_
— 20
,'
1 1 1 1 1 1 1 1 1 1 1 1
3
I I I I I I I
1 1 1 1 1 1 1 1 1 1 1 1
0 18
,'
I 1 1 1 I I 1 1 I I 1 I 1 1 1 I I 1 1 1 I
LL,
16
,
,
I I I I I I
14
� �
,'
I I I I I I I I
12
1 1 1 1 1 1 1 1 1 1 1 1
,'
10
' �'
a
,'
6
' ,'
I I I I I I I I I I I I
'__`__I___I__'__`__I____
4 5
Time (hours)
Pond 7P: Detention Pond
Stage -Discharge
Discharge (cfs)
■ Primary
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 10-Year Rainfall=4.99"
Printed 7/15/2021
Pond 7P: Detention Pond
Stage -Area -Storage
Surface/Horizontal :ed Area (sq-ft)
0
500
1,000
1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 6,500 7,000 7,500 8,000
■ Surface
I
I I I II I u I I I I I
■ Storage
656
u u
,
1
_______
1 1 1 11 1 u 1 1 1 1 u
654
1
1 1
1 1 1
1 1 1 11 1 1 1 1 1 1 1 u
653
1
1
11
1 1 1
1 1 1
1 1 1 11 II 1 1 1 1 1 1 1 1 u
1 1 1 1 1 1 1 1 1 1 1 1 1 u
652
1
1 11 u 1 1 1 1 1 1 1 1 1 u
651
1
1 1
1 1 1
1 1 1 1 11 1 1 1 1 1 1 1 1 1 11
ar ''
650
1
-r--rr---r
11
1
rr_
1
1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
___R___
1 11 1 u 1 1 1 1 1 1 1 1 1 u
c 0 649 ,
1
1
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
i 648
11
1
____1____I____1____II_______I_1____I__1__I____I_1___I___ I1_
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
N
11
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
W
647 ,
--r--rr--
1
r-r-r---rr-1----n---1---rr---l--rr---r-r-r--r-r--1---rr
1 1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
,
L_1_L___L1__1____1J___L__JL__
646
I
I I I
I I I II I II I I I I I I I I I II
III II
645
r-r---rr--r---nI---r--rr---1--�
1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
644
1
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
643
Custom Stage
Data
,
Block 32 Amendment
Prepared by Timmons Gi
Type II 24-hr 10-Year Rainfall=4.99"
Printed 7/15/2021
Summary for Link 11 L: DA Post Total
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 2.88" for 10-Year event
Inflow = 24.51 cfs @ 12.04 hrs, Volume= 1.622 of
Primary = 24.51 cfs @ 12.04 hrs, Volume= 1.622 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Link 11 L: DA Post Total
Hydrograph
Inflow Area=6.770
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I
I I I I I I I I
I I
I
Time (hours)
- ---- ❑ Inflow
I ❑ Primary
L=
F_ I
r- I
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr 100-Year Rainfall=8.19"
Printed 7/15/2021
Summary for Subcatchment 5S: Post -Developed (Detained)
[491 Hint: Tc<2dt may require smaller dt
Runoff = 67.16 cfs @ 11.96 hrs, Volume= 3.271 af, Depth> 5.80"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr 100-Year Rainfall=8.19"
Area (ac) CN Description
3.530
98 Paved roads w/curbs & sewers, HSG B
3.240
61 >75% Grass cover, Good, HSG B
6.770
80 Weighted Average
3.240
47.86% Pervious Area
3.530
52.14% Impervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
2.0
100
1.0000
0.84
Sheet Flow,
Grass: Short n= 0.150 P2= 3.38"
2.9
150
0.0150
0.86
Shallow Concentrated Flow,
Short Grass Pasture Kv= 7.0 fps
0.3
240
0.0200
14.46
102.19 Pipe Channel,
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.012 Corruqated PP, smooth interior
5.2 490 Total
Subcatchment 5S: Post -Developed (Detained)
Hydrograph
I I I I I I
I I I I I I I I I I I
6�
I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I I
I I I I I I I I I I I
_I
- r--r--r--r--I-- I
I I I I I I I I I
I I I I I I I I
I I I I I I I I
I I I J f i i I
I I I I I I I I
I I I I I I I I
I I I
_ L__L__L__I_
I I I I
I I I I
I I J f I I I I I I
I
I I I I I I I I I I
0 1 2 3 4 5 6 7 8 9 10 11 12
Time (h
I
_ _ ! _ ❑Runoff ____________
Type II 24-hr
;100-Year Rainfall=8.19"
Runoff Area=6.770 ac
Runoff Volume=3.271 of
_Runoff Depth>5.80"
} flow Length=490'
r Tc=5.2 min
--1--1--J--�--I-
CN=80
I I I I I I I
I I I I I I J I I I
I I I I I I
I I I I I I I I I I I
17 18 19 20 21 22 23 24
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr 100-Year Rainfall=8.19"
Summary for Subcatchment 12S: Pre -Developed
Runoff = 52.19 cfs @ 12.06 hrs, Volume= 3.398 af, Depth> 6.02"
Printed 7/15/2021
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr 100-Year Rainfall=8.19"
Area (ac) CN Description
6.770 82 Approved Existing CN
6.770 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
14.3 Direct Entry,
Subcatchment 12S: Pre -Developed
Hydrograph
I I I
I I I I I I I I I I
I I I I I I I e
Y
I peJllll- 4'hr
-1-00-)�ea1rlkainf`all'.81:1 ;I
RuriomAr6a_6170-66--
-R"otfyo)ulrne=$.308'I of
ItuinoXf bepth>B 62r!
-TC#14.3 min. --
CN $2
___ I--}__�__�__
■Runoff
I
I
I I I I
I I I I I I
I I I
I I I
I
I I I I I I
I I I
i
I I I I I I
I I I I
I I I
I I I I I
I I I I I
I I I I I I
I II I
I I I I I
I I I I I
I I I
I
I
I I I
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr 100-Year Rainfall=8.19"
Printed 7/15/2021
Summary for Pond 7P: Detention Pond
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 5.80" for 100-Year event
Inflow = 67.16 cfs @ 11.96 hrs, Volume= 3.271 of
Outflow = 65.23 cfs @ 11.98 hrs, Volume= 3.267 af, Atten= 3%, Lag= 1.2 min
Primary = 65.23 cfs @ 11.98 hrs, Volume= 3.267 of
Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Peak Elev= 652.11' @ 11.98 hrs Surf.Area= 4,902 sf Storage= 20,865 cf
Plug -Flow detention time=17.3 min calculated for 3.260 of (100% of inflow)
Center -of -Mass det. time= 16.5 min ( 814.1 - 797.6 )
Volume Invert
Avail.Storage Storage Description
#1 642.00'
46,174
cf Custom Stage Data (Irregular)Listed below (Recalc)
Elevation Surf.Area
Perim. Inc.Store Cum.Store Wet.Area
(feet)
(sq-ft)
(feet) (cubic -feet) (cubic -feet) (sq-ft)
642.00
195
549.0 0 0 195
644.00
661
30.0 810 810 24,115
646.00
1,361
75.0 1,980 2,790 24,506
648.00
2,296
116.0 3,616 6,407 25,157
650.00
3,438
152.0 5,696 12,103 25,970
652.00
4,818
190.0 8,217 20,320 27,060
654.00
6,426
232.0 11,205 31,525 28,532
656.00
8,261
266.0 14,649 46,174 29,968
Device Routing
Invert
Outlet Devices
#1 Primary
642.00'
36.0" Round Culvert
L= 105.0' CPP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 642.00' / 640.00' S= 0.0190 '/' Cc= 0.900
n= 0.012 Corrugated PP, smooth interior, Flow Area= 7.07 sf
#2 Device 1
642.25'
8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1
651.00'
60.0" Horiz. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#4 Primary
653.00'
25.0' long x 30.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=62.66 cfs @ 11.98 hrs HW=652.08' (Free Discharge)
1=Culvert (Passes 62.66 cfs of 78.70 cfs potential flow)
�2=Orifice/Grate (Orifice Controls 5.18 cfs @ 14.84 fps)
3=Orif ice/G rate (Weir Controls 57.48 cfs @ 3.39 fps)
= B road-C rested Rectangular Weir( Controls 0.00 cfs)
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr 100-Year Rainfall=8.19"
Printed 7/15/2021
Pond 712: Detention Pond
Hydrograph
---- -- -------I----T--I--,-1--T--r--I--,-- - - - -I- - -I -- - -
-- --1--
/ I I I I I I I I I I I I I I I I I I I I I I I
I- 1
6J 16 cfs
II
r -- 6623cfi - nfilaw.Area76TL ac
�IIIIIIIII I IIII I
- --I--
IIIIIIIII I
1 S ors q_-2Q' $ 5 cf _
I I I I I I I I
I I
IIIIIIIIIII
I I I I
I
-IIIIIIII IIIIIIIIIII
i I I I I I I I I I I I I I I I I I I I I
I I I I
I I I I I I I I I I I I I I I I I I I I
I I I I I I I I I I I I
4 5
Time (hours)
Pond 7P: Detention Pond
Stage -Discharge
Discharge (cfs)
■ Inflow
■ Primary
■ Primary
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr 100-Year Rainfall=8.19"
Printed 7/15/2021
Pond 7P: Detention Pond
Stage -Area -Storage
Surface/Horizontal :ed Area (sq-ft)
0
500
1,000
1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 6,500 7,000 7,500 8,000
■ Surface
I
I I I II I u I I I I I
■ Storage
656
u u
,
1
_______
1 1 1 11 1 u 1 1 1 1 u
654
1
1 1
1 1 1
1 1 1 11 1 1 1 1 1 1 1 u
653
1
1
11
1 1 1
1 1 1
1 1 1 11 II 1 1 1 1 1 1 1 1 u
1 1 1 1 1 1 1 1 1 1 1 1 1 u
652
1
1 11 u 1 1 1 1 1 1 1 1 1 u
651
1
1 1
1 1 1
1 1 1 1 11 1 1 1 1 1 1 1 1 1 11
ar ''
650
1
-r--rr---r
11
1
rr_
1
1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
___R___
1 11 1 u 1 1 1 1 1 1 1 1 1 u
c 0 649 ,
1
1
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
i 648
11
1
____1____I____1____II_______I_1____I__1__I____I_1___I___ I1_
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
N
11
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
W
647 ,
--r--rr--
1
r-r-r---rr-1----n---1---rr---l--rr---r-r-r--r-r--1---rr
1 1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
,
L_1_L___L1__1____1J___L__JL__
646
I
I I I
I I I II I II I I I I I I I I I II
III II
645
r-r---rr--r---nI---r--rr---1--�
1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
644
1
1 1
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
1 1 1 11 1 u 1 1 1 1 1 1 1 1 1 u
643
Custom Stage
Data
,
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr 100-Year Rainfall=8.19"
Printed 7/15/2021
Summary for Link 11 L: DA Post Total
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 5.79" for 100-Year event
Inflow = 65.23 cfs @ 11.98 hrs, Volume= 3.267 of
Primary = 65.23 cfs @ 11.98 hrs, Volume= 3.267 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Link 11 L: DA Post Total
Hydrograph
8
r
I
,__.__L__I__
I
I I I I I I
__-__L__I__
_Inflow Area=6.770
ac
g
�
I
5
5
,
J__y__
ti__I__J_
y
r r
I I
1
I
r r
I I I I I I I
I
r r r
I
I I I
I I I
_
4
I
I
I I I
I I I I
I I I
35
----r-r--r--�
1 1
1
__I__r__r__r_�_
1 1 1 1 1 1 1
--r-� -Y--r--r------r--r--r-I--
1 1 1 1 1 1 1
1 1 1 1
_
LL
3
'
--L--
-
1
L
1
--L --'-- i__1__L__i__J_
1 1 1
__L__I__J__1__L_ �__J__1__L__L_
1 1 1 1
�_-
1 1 1
25
----r-r--r--�
I 1
1
----r--r--� _�_
1 1 1 I I
--r-� -Y--r--r—---
I I I
1 1 1 1
--r--r—-r-I--
1 1 1 I
1
1
I I
1 1 1
I I I
1 1 1 1 I
I
1 1 1
1
I I
I
I I I I I I I
I I I I I I I
I I I I
Time (hours)
❑ Inflow
❑ Primary
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr Custom Rainfall=9.14"
Printed 7/15/2021
Summary for Subcatchment 5S: Post -Developed (Detained)
[491 Hint: Tc<2dt may require smaller dt
Runoff = 76.90 cfs @ 11.96 hrs, Volume= 3.778 af, Depth> 6.70"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr Custom Rainfall=9.14"
Area (ac) CN Description
3.530
98 Paved roads w/curbs & sewers, HSG B
3.240
61 >75% Grass cover, Good, HSG B
6.770
80 Weighted Average
3.240
47.86% Pervious Area
3.530
52.14% Impervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
2.0
100
1.0000
0.84
Sheet Flow,
Grass: Short n= 0.150 P2= 3.38"
2.9
150
0.0150
0.86
Shallow Concentrated Flow,
Short Grass Pasture Kv= 7.0 fps
0.3
240
0.0200
14.46
102.19 Pipe Channel,
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.012 Corruqated PP, smooth interior
5.2 490 Total
Subcatchment 5S: Post -Developed (Detained)
Hydrograph
85
I I i I I I I I
I I I
80
n
--r--r-T--�--T--r--rr__r__I_
75
70
65
I II II II II II II
I I I
-------------------------------
I
60
I I I I I I
I I I I I I I I I
55
I
I
50
N
_JIJJ1_-1_-L__L___.
— 45
I I I I I I I I I
o40
LL
-II -I
-r -T -1 -T -r --- r -I
35
I
30
25
----,--,--7--7-------
20
I I
r
5
I I I I _lssfJJ
Type II, 24-hr
---- �Ctustom-RainfalF-g I14"
Runbff Area=6.770 ad _
Run6ffll,V91ume=113.77$ elf
Runoff Depth>6.70'r-
--:-- -FIowL-enjth=490'-
I I
Tc=5.112 rniln
I I
I I I I I
GIN=8p
-r--r--r--r--I---I--I
I I I I I I I I I I
I I
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
❑ Runoff
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr Custom Rainfall=9.14"
Printed 7/15/2021
Summary for Subcatchment 12S: Pre -Developed
Runoff = 59.62 cfs @ 12.06 hrs, Volume= 3.909 af, Depth> 6.93"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Type II 24-hr Custom Rainfall=9.14"
Area (ac) CN Description
6.770 82 Approved Existing CN
6.770 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
14.3 Direct Entry,
65
60
55
50
45
40
N
35
3
LL 30
Subcatchment 12S: Pre -Developed
Hydrograph
U�
Type II 24-hr - ---;I- --
Custom Rainfall=9.14"
Runoff Area=6.770 ac
Runoff Volume=3.909 afll
Runoff Depth>6.93"
Tc=14.3 min
CN=81z
I I I I I
I I I I I I I I
I I I I I I
I I I
-T -r -r -r -I
■ Runoff
-
r--r--r --r' --7--r--r--r--
I I I I I I I I
I I I I I I I I I I I
I I I I I I I I I I I
------- -- ---------- ---- -- --
I I I I I I I I
I I I I i i I I I I
I I I I I I I I I I I
------------------------------
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I I
I I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I I I I I I I I I I
I I II I I I I I I I
I I I I I I I
I I I I I I I I I I
I I I I I
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr Custom Rainfall=9.14"
Printed 7/15/2021
Summary for Pond 7P: Detention Pond
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 6.70" for Custom event
Inflow = 76.90 cfs @ 11.96 hrs, Volume= 3.778 of
Outflow = 74.73 cfs @ 11.98 hrs, Volume= 3.773 af, Atten= 3%, Lag= 1.2 min
Primary = 74.73 cfs @ 11.98 hrs, Volume= 3.773 of
Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Peak Elev= 652.23' @ 11.98 hrs Surf.Area= 4,988 sf Storage= 21,425 cf
Plug -Flow detention time=16.8 min calculated for 3.765 of (100% of inflow)
Center -of -Mass det. time= 16.0 min ( 809.6 - 793.6 )
Volume Invert
Avail.Storage Storage Description
#1 642.00'
46,174
cf Custom Stage Data (Irregular)Listed below (Recalc)
Elevation Surf.Area
Perim. Inc.Store Cum.Store Wet.Area
(feet)
(sq-ft)
(feet) (cubic -feet) (cubic -feet) (sq-ft)
642.00
195
549.0 0 0 195
644.00
661
30.0 810 810 24,115
646.00
1,361
75.0 1,980 2,790 24,506
648.00
2,296
116.0 3,616 6,407 25,157
650.00
3,438
152.0 5,696 12,103 25,970
652.00
4,818
190.0 8,217 20,320 27,060
654.00
6,426
232.0 11,205 31,525 28,532
656.00
8,261
266.0 14,649 46,174 29,968
Device Routing
Invert
Outlet Devices
#1 Primary
642.00'
36.0" Round Culvert
L= 105.0' CPP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 642.00' / 640.00' S= 0.0190 '/' Cc= 0.900
n= 0.012 Corrugated PP, smooth interior, Flow Area= 7.07 sf
#2 Device 1
642.25'
8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads
#3 Device 1
651.00'
60.0" Horiz. Orifice/Grate C= 0.600
Limited to weir flow at low heads
#4 Primary
653.00'
25.0' long x 30.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
Primary OutFlow Max=71.72 cfs @ 11.98 hrs HW=652.19' (Free Discharge)
1=Culvert (Passes 71.72 cfs of 79.20 cfs potential flow)
�2=Orifice/Grate (Orifice Controls 5.21 cfs @ 14.92 fps)
3=Orif ice/G rate (Weir Controls 66.51 cfs @ 3.56 fps)
= B road-C rested Rectangular Weir( Controls 0.00 cfs)
Block 32 Amendment
Prepared by Timmons Gi
4 5 6 7
Type/1 24-hr Custom Rainfall=9.14"
Printed 7/15/2021
Pond 712: Detention Pond
Hydrograph
I
Ini!lowl!Alre4:06 770Ac-
pfaik_I'fEle- ttgZ7.-93
L-Storagq=21�425 cf -
I III; II II II
I I I I I I I I I
I I I I I I I I I I I I
I I I I I I I
I I I I
I I I I I I I I I I I
__I___I__ I__ __I___I___I__ __I __I___I__
I I I I I I I I I I I
I I I
__,__ 1__ 7__ T_--- __,__T__T__Y_ y__
Time (hours)
Pond 7P: Detention Pond
Stage -Discharge
Discharge (cfs)
■ Inflow
■ Primary
■ Primary
Block 32 Amendment
Prepared by Timmons Gi
Type/1 24-hr Custom Rainfall=9.14"
Printed 7/15/2021
Pond 7P: Detention Pond
Stage -Area -Storage
Surface/Horizontal :ed Area (sq-ft)
0
500
1,000
1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 6,500 7,000 7,500 8,000
■ Surface
I
I I I II I u I I I I I
■ Storage
656
u u
1 II u u
655 ,
___
1
_______
I I 1 11 1 u I 11 1 u
654
'
I
I I
I I 1
I I 1 11 1 I I I 11 1 u
653
I
I
II
1
I I 1
I 1 I
I I 1 11 1 I I I I 11 1 u
I I 1 11 II 1 I I I I 11 1 u
1 1 1 1 1 1 u
652 �
r-rr--rr-r--rr-
1
11 u 1 1 1 1 1 u
651
___L__1L___L_1_L_
I
I I
I I 1
__I________JI____I__J_I____I__I__I___J_L__I___JL
I 1 1 1 II 1 1 I I I I 1 1 1 II
650
1
1 11 1 u 1 1 1 1 u
c 0 649 ,
I
I
I I
I I 1 11 1 u 1 1 I I I I 11 1 u
i 648
I I
1
I I 1 11 1 u 1 1 I I I I 11 1 u
N
1
1 11 1 u 1 1 1 1 u
Mu--
647 ,
r--rr--
r-r-r---rr-1----n---1---rr---l--rr---r-r-r--r-r--1---rr
1
1 11 1 u 1 1 1 1 u
,
L1__1____1J___L__JL__ I__J_I___ I__I_ I___J_L_ --- __JL
646
I
I I I
I I I II I II I I I I I I I I I II
II II
645
-r
-rr
-r-r-r--
1
- rr--r--- n ---r--rr---1--� r-r--1---rr
I I 1 11 1 u 1 1 I I I I 1 1 1 u
644
I
I I
I I 1 11 1 u 1 1 I I I I 11 1 u
1 1 1 11 1 u 1 1 I I I I 11 1 u
643
Custom Stage
Data
,
Block 32 Amendment
Prepared by Timmons Gi
Type 11 24-hr Custom Rainfall=9.14"
Printed 7/15/2021
Summary for Link 11 L: DA Post Total
Inflow Area = 6.770 ac, 52.14% Impervious, Inflow Depth > 6.69" for Custom event
Inflow = 74.73 cfs @ 11.98 hrs, Volume= 3.773 of
Primary = 74.73 cfs @ 11.98 hrs, Volume= 3.773 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs
Link 11 L: DA Post Total
Hydrograph
I I I I I I I I I I
I I
80
--1--r--r--I--l--r--�-- �- r
as -
-I -;-- "��,
-Inflow Area=6.770 ac
75<.rs
I I I I I I I I I I
70
I I I I I I I I I I
65
I I I I I
I I I I I I I I I I
I I
I I I I I I I I I
60
I I I I I I I
( I I I I I I I I I I
55
I I I
I I I I I
I I I
I I I I I I I I
50
I
I I
45
1
49
I I I 1 1 I I 1 I
1 1 1 I
--I I I 1 1 I I 1 I
I I
1 1 1
I I I I I
I I I
I I
I I I I I I I I I
30
I I I I I
I I I I I
I I I I
I I I I I I I
----J--'--L-------'--L--'--J-
--L----J--1--L --'--J--'--L--L --'--
25
I I I I I I I I I �
I I I I I I I I I I I
20
15
I I i I I
I I
I I I I I I
10
I I I
5
0
0
1
2 3 4 5 6 7 8 9 10 11 12
13 14 15 16 17 18 19 20 21 22 23 24
Time (hours)
❑ Inflow
❑ Primary