SW3181002_Design Calculations_20190116

BOHLER ENGINEERING 1927 S TRYON ST. ♦ SUITE 310 ♦ CHARLOTTE, NC 28203 ♦ 980.272.3400

STORMWATER MANAGEMENT REPORT
PREPARED FOR:

THE H&H HOMES
WAXHAW INDIAN TRAIL RD
INDIAN TRAIL, NC
UNION COUNTY
BEPC #NCC162130

September 25, 2018

PREPARED BY:
BOHLER ENGINEERING, NC, PLLC
1927 S. TYRON ST. SUITE 310
CHARLOTTE, NC 28203
[phone]

__ ________________________________
NORTH CAROLINA LICENSE #043610
MICHAEL THEBERGE, P.E.

PROFESSIONAL CERTIFICATION: I HEREBY CERTIFY THAT THESE DOCUMENTS WERE PREPARED OR APPROVED BY ME, AND
THAT I AM A DULY LICENSED REGISTERED ENGINEER UNDER THE LAWS OF THE STATE OF NORTH CAROLINA

CIVIL & CONSULTING ENGINEERS▪SURVEYORS▪TRAFFIC CONSULTANTS
www.bohlereng.com

2

Table of Contents

General Project Description ............................................................................................................... 3

Stormwater Management Analysis and BMP Calculations ................................................................ 4

Appendix ............................................................................................................................................ 6
HydroCAD Output .............................................................................................................................
Stormsewer Output ...........................................................................................................................

3

General Project Description/Stormwater Management

GENERAL PROJECT OVERVIEW AND EXISTING CONDITIONS

The subject site is located along Waxhaw Indian Trail, in Union County. The project site is
currently farm land and wooded area which consists of approximately 13.71 acres and will
include approximately 48 single family lots.

The site is majority pasture with some wooded areas (type B soils), with average existing slopes
of 3% to 5%. There is currently no stormwater best management practices provided on the
site. Located on the adjacent property to the northside of the site is three existing natural
ponds. There is off-site area examined in this analysis and is included in our proposed SCM.

STORMWATER REQUIREMENTS AND DESIGN OVERVIEW

This project is located in the East Fork Twelvemile Creek which falls under the Catawba river
basin district and is adjacent to Davis Mine Creek. This project is classified as a high-density
project because the overall drainage area has greater than 12% built upon area.

Stormwater quality treatment systems shall treat the runoff generated from the first inch of
rainfall.

All structural stormwater treatment systems used to meet these requirements shall be designed
to have a minimum of 85% average annual removal for total suspended solids and 70%
average annual removal for total phosphorus.

General engineering design criteria shall be accordance with 15 A NCAC 2H. 1008(c) in the
design manual.

The peak discharge is attenuated for the 2-year, 24-hr storm and the 25-year, 24-hr storm. The
100-year, 24-hr storm event is being passed through both wet ponds outlet control structure
without an emergency spillway. The emergency spillway is not required since the maximum
elevation the 100-year storm will be in the pond is less than the top of the pond. The 100-year
storm event was modeled so that the water quality and secondary orifices were clogged to
confirm that the top of riser and outlet pipe would pass the required water. We modeled the
water quality and secondary orifices as clogged because this is hydrologically how the outlet
control structure would function.

Areas not controlled by systems due to topographic challenges are sheet flowing through the
vegetated buffer, but all proposed impervious areas are treated within the proposed stormwater
control measures.

Please note that all runoff from the roofs of the homes is to be routed to underground storm
drains that discharge into the wet detention pond. Some homes will have direct tie-ins of their
roof drains to nearby structures and some will flow overland and in channels to nearby inlets.

4

STORMSEWER DESIGN

Stormwater run-off from the site will be directed to the existing outfall locations via a system of
storm sewer pipes. The storm sewer was modeled in Hydraflow Storm Sewers Extension for
Autodesk AutoCAD Civil 3D. The storm sewer pipes were modeled to ensure their adequate
capacity with a minimum slope of 0.5% to promote flushing of the pipes.

Stormwater Management and BMP Calculations

PRE VS. POST ANALYSIS PEAK Analysis

See table below for final flow calculations for the pre and post conditions. It should be noted
that time of concentration is accounted for in the summation of the combined peak discharge
values. In addition, only the 2-year and 25-year are required to be attenuated.

DRAINAGE AREA  
2‐YR 24 
HR(cfs) 
25‐YR 24 
HR(cfs) 
POI A COMBINED:       
Pre A 1 1.80 8.89 
Post A1, Post A2, Post A3 1.72 7.06 
POI B:  
Pre B 3.51 20.58 
Post B  0.87 3.61 
POI C:    
Pre C 1.04 5.86 
Post C 0.22 0.90 
POI D:    
Pre D 0.16 1.31 
Post D  0.14 0.54 
POI E:    
Pre E 3.60 9.37 
Post E  0.11 0.44 
POI F:    
Pre F 0.12 0.93 
Post F  0.06 0.49 

All associated calculations have been provided within the Appendix section of this report.

5

WATER QUALITY

Water quality treatment of the 1” water quality volume, is also provided within the proposed
above-ground wet detention pond, and is to be detained between 2-5days (See appendix for
calculations).

6

Appendix
DESIGN:
GIVEN:
15.17 Ac.
70%
8.0 FEET
70%
SA/DA = 1.17 % = 0.0117 updated MDC
SA REQUIRED = 15.17 Ac. X 0.0117
= 0.18 Ac.
= 7,731 SF
THE VOLUME FOR THE 1" STORM EVENT CAN BE CALCULATED AS:
Design Rainfall = 1 Inch
Drainage Area = 15.17 Acres
Rv = 0.05 + 0.9(I)
I = Percent Impervious = 70%
Rv = 0.68 in./in.
V1 =0.860 acre-feet = 37,446
ft3
Pond Height above Orifice = 669.44 feet
Orifice Invert Elevation = 668.00 feet
Orifice Diameter (D) = 2.50 inches = 0.21 feet
Orifice Area (a) = 0.0341 square feet
Gravitational Constant (g) = 32.2 ft/sec2
Head (H) = 1.34 feet
Driving Head (H O) =0.445 feet
Discharge Coefficient (C D) =0.6
Drawdown rate (Q) = 0.110 cfs
Time (t) = 341,888 seconds = 3.96 days
Note:
The above calculation is based on the orifice equation where:
0.597 acre-feet
3.741 acre-feet
16.0%
Cottages West (WET POND #1)
WATER QUALITY TO MEET 85% TSS REMOVAL
DRAINAGE AREA TO FACILITY =
LAND USE = Single-Family Detached
ESTIMATED PERCENT IMPERVIOUS =
1) SA/DA RATIO:
AVERAGE POOL DEPTH =
PERCENT IMPERVIOUS =
Forebay volume:
Mainpool Volume:
Percentage:
2) TEMPORARY WATER QUALITY POOL REQUIREMENTS
PROVIDE VOLUME TO DETAIN THE 1" STORM EVENT ABOVE THE ELEVATION
ALLOCATED AS A PERMANENT POOL
V1 = (Design Rainfall)(Rv)(Drainage Area)
3) Pond Drawdown Time
4) Forebay vs Main Pool Percentage
10/15/2018 11:12 AM Page 1 of 3
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 1HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 12P: Wetpond #1 Permant Pond
[43] Hint: Has no inflow (Outflow=Zero)
Volume Invert Avail.Storage Storage Description
#1 646.00' 3.741 af Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (acres) (feet) (acre-feet) (acre-feet) (acres)
646.00 0.017 159.0 0.000 0.000 0.017
647.00 0.025 180.0 0.021 0.021 0.031
648.00 0.034 201.0 0.029 0.050 0.046
649.00 0.043 222.0 0.038 0.089 0.063
650.00 0.054 244.0 0.048 0.137 0.082
651.00 0.066 265.0 0.060 0.197 0.103
652.00 0.078 286.4 0.072 0.269 0.125
653.00 0.092 306.1 0.085 0.354 0.147
654.00 0.106 322.6 0.099 0.453 0.168
655.00 0.122 339.1 0.114 0.567 0.189
656.00 0.138 355.7 0.130 0.697 0.212
657.00 0.154 372.2 0.146 0.842 0.235
658.00 0.172 388.7 0.163 1.005 0.260
659.00 0.190 405.1 0.181 1.186 0.285
660.00 0.209 421.5 0.199 1.386 0.312
661.00 0.229 437.8 0.219 1.605 0.339
662.00 0.249 454.1 0.239 1.844 0.368
663.00 0.270 470.4 0.259 2.103 0.397
664.00 0.292 486.6 0.281 2.384 0.427
665.00 0.315 502.8 0.303 2.687 0.459
666.00 0.339 518.9 0.327 3.014 0.491
667.00 0.363 534.4 0.351 3.365 0.523
668.00 0.388 549.3 0.375 3.741 0.555
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 2HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Stage-Area-Storage for Pond 12P: Wetpond #1 Permant Pond
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
646.00 0.017 0.000
646.25 0.019 0.004
646.50 0.021 0.009
646.75 0.023 0.015
647.00 0.025 0.021
647.25 0.027 0.027
647.50 0.029 0.034
647.75 0.032 0.042
648.00 0.034 0.050
648.25 0.036 0.059
648.50 0.038 0.068
648.75 0.041 0.078
649.00 0.043 0.089
649.25 0.046 0.100
649.50 0.048 0.111
649.75 0.051 0.124
650.00 0.054 0.137
650.25 0.057 0.151
650.50 0.060 0.166
650.75 0.063 0.181
651.00 0.066 0.197
651.25 0.069 0.214
651.50 0.072 0.231
651.75 0.075 0.250
652.00 0.078 0.269
652.25 0.081 0.289
652.50 0.085 0.310
652.75 0.088 0.331
653.00 0.092 0.354
653.25 0.095 0.377
653.50 0.099 0.401
653.75 0.102 0.427
654.00 0.106 0.453
654.25 0.110 0.480
654.50 0.114 0.508
654.75 0.118 0.537
655.00 0.122 0.567
655.25 0.126 0.598
655.50 0.130 0.630
655.75 0.134 0.663
656.00 0.138 0.697
656.25 0.142 0.732
656.50 0.146 0.767
656.75 0.150 0.804
657.00 0.154 0.842
657.25 0.158 0.882
657.50 0.163 0.922
657.75 0.167 0.963
658.00 0.172 1.005
658.25 0.176 1.049
658.50 0.181 1.094
658.75 0.185 1.139
659.00 0.190 1.186
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
659.25 0.195 1.234
659.50 0.199 1.284
659.75 0.204 1.334
660.00 0.209 1.386
660.25 0.214 1.439
660.50 0.219 1.493
660.75 0.224 1.548
661.00 0.229 1.605
661.25 0.234 1.663
661.50 0.239 1.722
661.75 0.244 1.782
662.00 0.249 1.844
662.25 0.254 1.906
662.50 0.259 1.971
662.75 0.265 2.036
663.00 0.270 2.103
663.25 0.275 2.171
663.50 0.281 2.241
663.75 0.286 2.312
664.00 0.292 2.384
664.25 0.298 2.458
664.50 0.303 2.533
664.75 0.309 2.609
665.00 0.315 2.687
665.25 0.321 2.767
665.50 0.327 2.848
665.75 0.333 2.930
666.00 0.339 3.014
666.25 0.345 3.100
666.50 0.351 3.187
666.75 0.357 3.275
667.00 0.363 3.365
667.25 0.369 3.457
667.50 0.375 3.550
667.75 0.382 3.644
668.00 0.388 3.741
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 3HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 13P: Wetpond #1 Forebay
[43] Hint: Has no inflow (Outflow=Zero)
Volume Invert Avail.Storage Storage Description
#1 661.00' 0.597 af Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (acres) (feet) (acre-feet) (acre-feet) (acres)
661.00 0.047 193.5 0.000 0.000 0.047
662.00 0.057 211.7 0.052 0.052 0.061
663.00 0.067 229.9 0.062 0.114 0.077
664.00 0.078 248.1 0.072 0.186 0.094
665.00 0.089 266.2 0.083 0.270 0.112
666.00 0.102 284.4 0.095 0.365 0.131
667.00 0.116 302.5 0.109 0.474 0.152
668.00 0.130 316.5 0.123 0.597 0.169
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 4HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Stage-Area-Storage for Pond 13P: Wetpond #1 Forebay
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
661.00 0.047 0.000
661.10 0.048 0.005
661.20 0.049 0.010
661.30 0.050 0.015
661.40 0.051 0.020
661.50 0.052 0.025
661.60 0.053 0.030
661.70 0.054 0.035
661.80 0.055 0.041
661.90 0.056 0.046
662.00 0.057 0.052
662.10 0.058 0.058
662.20 0.059 0.064
662.30 0.060 0.069
662.40 0.061 0.075
662.50 0.062 0.082
662.60 0.063 0.088
662.70 0.064 0.094
662.80 0.065 0.101
662.90 0.066 0.107
663.00 0.067 0.114
663.10 0.068 0.121
663.20 0.069 0.127
663.30 0.070 0.134
663.40 0.071 0.142
663.50 0.072 0.149
663.60 0.073 0.156
663.70 0.075 0.163
663.80 0.076 0.171
663.90 0.077 0.179
664.00 0.078 0.186
664.10 0.079 0.194
664.20 0.080 0.202
664.30 0.081 0.210
664.40 0.082 0.218
664.50 0.083 0.227
664.60 0.085 0.235
664.70 0.086 0.244
664.80 0.087 0.252
664.90 0.088 0.261
665.00 0.089 0.270
665.10 0.090 0.279
665.20 0.092 0.288
665.30 0.093 0.297
665.40 0.094 0.306
665.50 0.095 0.316
665.60 0.097 0.325
665.70 0.098 0.335
665.80 0.099 0.345
665.90 0.101 0.355
666.00 0.102 0.365
666.10 0.103 0.375
666.20 0.105 0.386
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
666.30 0.106 0.396
666.40 0.107 0.407
666.50 0.109 0.418
666.60 0.110 0.429
666.70 0.112 0.440
666.80 0.113 0.451
666.90 0.115 0.463
667.00 0.116 0.474
667.10 0.117 0.486
667.20 0.119 0.498
667.30 0.120 0.509
667.40 0.122 0.522
667.50 0.123 0.534
667.60 0.124 0.546
667.70 0.126 0.559
667.80 0.127 0.571
667.90 0.129 0.584
668.00 0.130 0.597
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 5HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 16P: Wetpond #1Temp pool
[43] Hint: Has no inflow (Outflow=Zero)
Volume Invert Avail.Storage Storage Description
#1 668.00' 1.234 af Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (acres) (feet) (acre-feet) (acre-feet) (acres)
668.00 0.534 668.0 0.000 0.000 0.534
669.00 0.629 706.0 0.581 0.581 0.631
670.00 0.678 724.9 0.653 1.234 0.683
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 6HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Stage-Area-Storage for Pond 16P: Wetpond #1Temp pool
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
668.00 0.534 0.000
668.02 0.536 0.011
668.04 0.538 0.021
668.06 0.539 0.032
668.08 0.541 0.043
668.10 0.543 0.054
668.12 0.545 0.065
668.14 0.547 0.076
668.16 0.549 0.087
668.18 0.551 0.098
668.20 0.552 0.109
668.22 0.554 0.120
668.24 0.556 0.131
668.26 0.558 0.142
668.28 0.560 0.153
668.30 0.562 0.164
668.32 0.564 0.176
668.34 0.565 0.187
668.36 0.567 0.198
668.38 0.569 0.210
668.40 0.571 0.221
668.42 0.573 0.232
668.44 0.575 0.244
668.46 0.577 0.255
668.48 0.579 0.267
668.50 0.581 0.279
668.52 0.582 0.290
668.54 0.584 0.302
668.56 0.586 0.314
668.58 0.588 0.325
668.60 0.590 0.337
668.62 0.592 0.349
668.64 0.594 0.361
668.66 0.596 0.373
668.68 0.598 0.385
668.70 0.600 0.397
668.72 0.602 0.409
668.74 0.604 0.421
668.76 0.605 0.433
668.78 0.607 0.445
668.80 0.609 0.457
668.82 0.611 0.469
668.84 0.613 0.481
668.86 0.615 0.494
668.88 0.617 0.506
668.90 0.619 0.518
668.92 0.621 0.531
668.94 0.623 0.543
668.96 0.625 0.556
668.98 0.627 0.568
669.00 0.629 0.581
669.02 0.630 0.593
669.04 0.631 0.606
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
669.06 0.632 0.619
669.08 0.633 0.631
669.10 0.634 0.644
669.12 0.635 0.657
669.14 0.636 0.669
669.16 0.637 0.682
669.18 0.638 0.695
669.20 0.639 0.708
669.22 0.640 0.720
669.24 0.641 0.733
669.26 0.642 0.746
669.28 0.643 0.759
669.30 0.644 0.772
669.32 0.644 0.785
669.34 0.645 0.798
669.36 0.646 0.810
669.38 0.647 0.823
669.40 0.648 0.836
669.42 0.649 0.849
669.44 0.650 0.862
669.46 0.651 0.875
669.48 0.652 0.888
669.50 0.653 0.901
669.52 0.654 0.914
669.54 0.655 0.928
669.56 0.656 0.941
669.58 0.657 0.954
669.60 0.658 0.967
669.62 0.659 0.980
669.64 0.660 0.993
669.66 0.661 1.007
669.68 0.662 1.020
669.70 0.663 1.033
669.72 0.664 1.046
669.74 0.665 1.060
669.76 0.666 1.073
669.78 0.667 1.086
669.80 0.668 1.100
669.82 0.669 1.113
669.84 0.670 1.126
669.86 0.671 1.140
669.88 0.672 1.153
669.90 0.673 1.167
669.92 0.674 1.180
669.94 0.675 1.194
669.96 0.676 1.207
669.98 0.677 1.221
670.00 0.678 1.234
DESIGN:
GIVEN:
3.13 Ac.
70%
3 FEET
70%
SA/DA = 2.51 % = 0.0251 Updated MDC
SA REQUIRED = 3.13 Ac. X 0.0251
= 0.08 Ac.
= 3,422 SF
THE VOLUME FOR THE 1" STORM EVENT CAN BE CALCULATED AS:
Design Rainfall = 1 Inch
Drainage Area = 3.13 Acres
Rv = 0.05 + 0.9(I)
I = Percent Impervious = 70%
Rv = 0.68 in./in.
V1 =0.177 acre-feet = 7,726
ft3
Pond Height above Orifice = 654.18 feet
Orifice Invert Elevation = 653.00 feet
Orifice Diameter (D) = 1.20 inches = 0.10 feet
Orifice Area (a) = 0.0079 square feet
Gravitational Constant (g) = 32.2 ft/sec2
Head (H) = 1.13 feet
Driving Head (H O) =0.377 feet
Discharge Coefficient (C D) =0.6
Drawdown rate (Q) = 0.023 cfs
Time (t) = 332,887 seconds = 3.85 days
Note:
The above calculation is based on the orifice equation where:
0.059 acre-feet
0.344 acre-feet
17.2%
AVERAGE POOL DEPTH =
1) SA/DA RATIO:
PROVIDE VOLUME TO DETAIN THE 1" STORM EVENT ABOVE THE ELEVATION
PERCENT IMPERVIOUS =
2) TEMPORARY WATER QUALITY POOL REQUIREMENTS
COTTAGES WEST (WET POND #2)
WATER QUALITY TO MEET 85% TSS REMOVAL
Single Family DetachedLAND USE =
ESTIMATED PERCENT IMPERVIOUS =
DRAINAGE AREA TO FACILITY =
Percentage:
3) Pond Drawdown Time
ALLOCATED AS A PERMANENT POOL
V1 = (Design Rainfall)(Rv)(Drainage Area)
4) Forebay vs Main Pool Percentage
Forebay volume:
Mainpool Volume:
10/15/2018 11:12 AM Page 2 of 3
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 1HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 11P: Wetpond #2 Permant Pond
[43] Hint: Has no inflow (Outflow=Zero)
Volume Invert Avail.Storage Storage Description
#1 645.00' 0.344 af Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (acres) (feet) (acre-feet) (acre-feet) (acres)
645.00 0.006 148.4 0.000 0.000 0.006
646.00 0.014 167.9 0.010 0.010 0.018
647.00 0.022 184.0 0.018 0.028 0.029
648.00 0.031 199.9 0.026 0.054 0.041
649.00 0.041 215.7 0.036 0.090 0.054
650.00 0.052 231.5 0.046 0.136 0.068
651.00 0.063 247.3 0.057 0.194 0.083
652.00 0.075 263.0 0.069 0.263 0.098
653.00 0.088 278.8 0.081 0.344 0.115
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 2HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Stage-Area-Storage for Pond 11P: Wetpond #2 Permant Pond
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
645.00 0.006 0.000
645.10 0.007 0.001
645.20 0.007 0.001
645.30 0.008 0.002
645.40 0.009 0.003
645.50 0.010 0.004
645.60 0.010 0.005
645.70 0.011 0.006
645.80 0.012 0.007
645.90 0.013 0.008
646.00 0.014 0.010
646.10 0.015 0.011
646.20 0.015 0.013
646.30 0.016 0.014
646.40 0.017 0.016
646.50 0.018 0.018
646.60 0.019 0.019
646.70 0.019 0.021
646.80 0.020 0.023
646.90 0.021 0.025
647.00 0.022 0.028
647.10 0.023 0.030
647.20 0.024 0.032
647.30 0.025 0.035
647.40 0.025 0.037
647.50 0.026 0.040
647.60 0.027 0.042
647.70 0.028 0.045
647.80 0.029 0.048
647.90 0.030 0.051
648.00 0.031 0.054
648.10 0.032 0.057
648.20 0.033 0.060
648.30 0.034 0.064
648.40 0.035 0.067
648.50 0.036 0.071
648.60 0.037 0.074
648.70 0.038 0.078
648.80 0.039 0.082
648.90 0.040 0.086
649.00 0.041 0.090
649.10 0.042 0.094
649.20 0.043 0.098
649.30 0.044 0.103
649.40 0.045 0.107
649.50 0.046 0.112
649.60 0.047 0.116
649.70 0.049 0.121
649.80 0.050 0.126
649.90 0.051 0.131
650.00 0.052 0.136
650.10 0.053 0.141
650.20 0.054 0.147
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
650.30 0.055 0.152
650.40 0.056 0.158
650.50 0.057 0.164
650.60 0.058 0.169
650.70 0.060 0.175
650.80 0.061 0.181
650.90 0.062 0.187
651.00 0.063 0.194
651.10 0.064 0.200
651.20 0.065 0.206
651.30 0.066 0.213
651.40 0.068 0.220
651.50 0.069 0.227
651.60 0.070 0.234
651.70 0.071 0.241
651.80 0.073 0.248
651.90 0.074 0.255
652.00 0.075 0.263
652.10 0.076 0.270
652.20 0.078 0.278
652.30 0.079 0.286
652.40 0.080 0.294
652.50 0.081 0.302
652.60 0.083 0.310
652.70 0.084 0.318
652.80 0.085 0.327
652.90 0.087 0.335
653.00 0.088 0.344
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 3HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 14P: Wetpond #2 Forebay
[43] Hint: Has no inflow (Outflow=Zero)
Volume Invert Avail.Storage Storage Description
#1 649.00' 0.059 af Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (acres) (feet) (acre-feet) (acre-feet) (acres)
649.00 0.004 78.9 0.000 0.000 0.004
650.00 0.008 105.5 0.006 0.006 0.013
651.00 0.014 132.2 0.011 0.017 0.025
652.00 0.021 158.8 0.017 0.034 0.040
653.00 0.029 185.5 0.025 0.059 0.057
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 4HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Stage-Area-Storage for Pond 14P: Wetpond #2 Forebay
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
649.00 0.004 0.000
649.05 0.004 0.000
649.10 0.004 0.000
649.15 0.005 0.001
649.20 0.005 0.001
649.25 0.005 0.001
649.30 0.005 0.001
649.35 0.005 0.002
649.40 0.005 0.002
649.45 0.006 0.002
649.50 0.006 0.002
649.55 0.006 0.003
649.60 0.006 0.003
649.65 0.006 0.003
649.70 0.007 0.004
649.75 0.007 0.004
649.80 0.007 0.004
649.85 0.007 0.005
649.90 0.008 0.005
649.95 0.008 0.005
650.00 0.008 0.006
650.05 0.008 0.006
650.10 0.009 0.007
650.15 0.009 0.007
650.20 0.009 0.008
650.25 0.009 0.008
650.30 0.010 0.009
650.35 0.010 0.009
650.40 0.010 0.010
650.45 0.010 0.010
650.50 0.011 0.011
650.55 0.011 0.011
650.60 0.011 0.012
650.65 0.012 0.012
650.70 0.012 0.013
650.75 0.012 0.013
650.80 0.013 0.014
650.85 0.013 0.015
650.90 0.013 0.015
650.95 0.014 0.016
651.00 0.014 0.017
651.05 0.014 0.017
651.10 0.015 0.018
651.15 0.015 0.019
651.20 0.015 0.020
651.25 0.016 0.020
651.30 0.016 0.021
651.35 0.016 0.022
651.40 0.017 0.023
651.45 0.017 0.024
651.50 0.017 0.025
651.55 0.018 0.025
651.60 0.018 0.026
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
651.65 0.018 0.027
651.70 0.019 0.028
651.75 0.019 0.029
651.80 0.019 0.030
651.85 0.020 0.031
651.90 0.020 0.032
651.95 0.021 0.033
652.00 0.021 0.034
652.05 0.021 0.035
652.10 0.022 0.036
652.15 0.022 0.037
652.20 0.022 0.038
652.25 0.023 0.040
652.30 0.023 0.041
652.35 0.024 0.042
652.40 0.024 0.043
652.45 0.024 0.044
652.50 0.025 0.046
652.55 0.025 0.047
652.60 0.026 0.048
652.65 0.026 0.049
652.70 0.026 0.051
652.75 0.027 0.052
652.80 0.027 0.053
652.85 0.028 0.055
652.90 0.028 0.056
652.95 0.029 0.058
653.00 0.029 0.059
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 5HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Summary for Pond 15P: Wetpond #2 Temp pool
[43] Hint: Has no inflow (Outflow=Zero)
Volume Invert Avail.Storage Storage Description
#1 653.00' 0.326 af Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (acres) (feet) (acre-feet) (acre-feet) (acres)
653.00 0.122 301.0 0.000 0.000 0.122
654.00 0.169 349.0 0.145 0.145 0.179
655.00 0.194 373.0 0.181 0.326 0.212
Type II 24-hr 100 Yr - 24 hr Rainfall=7.77"Cottages II Pond Routing
Printed 10/15/2018Prepared by Bohler Engineering
Page 6HydroCAD® 10.00-20 s/n 09920 © 2017 HydroCAD Software Solutions LLC
Stage-Area-Storage for Pond 15P: Wetpond #2 Temp pool
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
653.00 0.122 0.000
653.02 0.123 0.002
653.04 0.124 0.005
653.06 0.125 0.007
653.08 0.125 0.010
653.10 0.126 0.012
653.12 0.127 0.015
653.14 0.128 0.018
653.16 0.129 0.020
653.18 0.130 0.023
653.20 0.131 0.025
653.22 0.132 0.028
653.24 0.133 0.031
653.26 0.133 0.033
653.28 0.134 0.036
653.30 0.135 0.039
653.32 0.136 0.041
653.34 0.137 0.044
653.36 0.138 0.047
653.38 0.139 0.050
653.40 0.140 0.052
653.42 0.141 0.055
653.44 0.142 0.058
653.46 0.143 0.061
653.48 0.144 0.064
653.50 0.145 0.067
653.52 0.145 0.069
653.54 0.146 0.072
653.56 0.147 0.075
653.58 0.148 0.078
653.60 0.149 0.081
653.62 0.150 0.084
653.64 0.151 0.087
653.66 0.152 0.090
653.68 0.153 0.093
653.70 0.154 0.096
653.72 0.155 0.100
653.74 0.156 0.103
653.76 0.157 0.106
653.78 0.158 0.109
653.80 0.159 0.112
653.82 0.160 0.115
653.84 0.161 0.118
653.86 0.162 0.122
653.88 0.163 0.125
653.90 0.164 0.128
653.92 0.165 0.132
653.94 0.166 0.135
653.96 0.167 0.138
653.98 0.168 0.141
654.00 0.169 0.145
654.02 0.169 0.148
654.04 0.170 0.152
Elevation
(feet)
Surface
(acres)
Storage
(acre-feet)
654.06 0.170 0.155
654.08 0.171 0.158
654.10 0.171 0.162
654.12 0.172 0.165
654.14 0.172 0.169
654.16 0.173 0.172
654.18 0.173 0.176
654.20 0.174 0.179
654.22 0.174 0.183
654.24 0.175 0.186
654.26 0.175 0.190
654.28 0.176 0.193
654.30 0.176 0.197
654.32 0.177 0.200
654.34 0.177 0.204
654.36 0.178 0.207
654.38 0.178 0.211
654.40 0.179 0.214
654.42 0.179 0.218
654.44 0.180 0.222
654.46 0.180 0.225
654.48 0.181 0.229
654.50 0.181 0.232
654.52 0.182 0.236
654.54 0.182 0.240
654.56 0.183 0.243
654.58 0.183 0.247
654.60 0.184 0.251
654.62 0.184 0.254
654.64 0.185 0.258
654.66 0.185 0.262
654.68 0.186 0.265
654.70 0.186 0.269
654.72 0.187 0.273
654.74 0.187 0.277
654.76 0.188 0.280
654.78 0.188 0.284
654.80 0.189 0.288
654.82 0.189 0.292
654.84 0.190 0.296
654.86 0.190 0.299
654.88 0.191 0.303
654.90 0.191 0.307
654.92 0.192 0.311
654.94 0.192 0.315
654.96 0.193 0.318
654.98 0.193 0.322
655.00 0.194 0.326