20011549 Ver 1_Revised Stormwater Info_20020917

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WITHERS &- RAVENEL
ENGINEERS I PLANNERS I SURVEYORS
iii MacKenan Drive
CARY, NORTH CAROLINA, 27521
[phone]
FAX [phone]oo8
To: NC Division of Water Quality
2321 Crabtree Blvd
Raleigh, North Carolina 276o4
WE ARE SENDING YOU
? Shop Drawings
? Copy of Letter
LETTER OF TRANSMMAL DATE /17/02. los No. 201113.0

ATTENTION Todd St. John
PHONE # [phone]
RE: Lon Lake Subdivision
DWQ Project 611549
0 r)
(r; i

„r
® Attached ? Under separate cover via _
? Prints ® Plans ? Samples
? Change order ? Diskette ?
the following items:
? Specifications
COPIES DATE NO. DESCRIPTION
1 9/17/02 Revised Storm Water Management Plan, Phases 2 &
1 9/17/02 Supporting Calculations
1 9/17/02 Response Letter

THESE ARE TRANSMITTED as checked below:
? For approval ? Approved as submitted
? For your use ? Approved as noted
? As requested ? Returned for corrections
? For review and comment ?
? FOR BIDS DUE 20 ? PRINTS RETURNED AFTER LOAN TO US
REMARKS:
COPY TO: Ale
? Resubmit
? Submit
? Return
- copies for approval
copies for distribution
corrected prints
SIGNED: Ken Jesneck. PE
if enclosures are not as noted, kindly notify as at once.
OF WAr'F
R9G Michael F. Easley
vj y Governor
> r William Ross, Secretary
Department of Environment and Natural Resources
o -mac
Gregory J. Thorpe. PhD.
- Acting Director
Division of Water Quality
Deceinbel21, 2001
Wake County
DWQ Project # 01-1549
. If you do not accept any of the conditions of this certification, you may ask for an adjudicatory hearing. You
must act within 60 days of the date that you receive this letter. To ask for a hearing, send a written petition which
conforms to Chapter 150B of the North Carolina General Statutes to the Office of Administrative Hearings PO Box
27447, Raleigh, N.C. 27611-7447. This certification and its conditions are final and binding unless you ask for a
hearing.
This letter completes the review 2of the Division of Water Quality under Section 401 of the Clean Water Act. if
you have any questions, please telephone John Domey at 919-733-9721 or Tom Stevens at our Washington Office
at 252-946-6481.
Sincerely,
Steven
- Attach enf°=?1 ?-
cc -Corps of Englnee s
"`^ M !Raleigh DWQ Regio
?IIPy
-'Central Files
"Ron Ferrell, WRP,:
Todd St John DWQ
r _ - -ANelso Paul
cr' :
Raleigh Field Office
nal Office' ••?? - _ -
?t•
riturm
- s -- Division of Water Quality 1621 Mal Service Center Raleigh, NC 27699-1621
Wetlands/401 Unit: [phone]
Fax: [phone]
WITHER
s r R.AVE-:NE-.L
PHASES 2 AND 3 OF THE
STORMWATER MANAGEMENT PLAN
SUPPORTING DESIGN CALCULATIONS
LONG LAKE SUBDIVISION
Raleigh, North Carolina
Prepared For:
PULTE HOME CORPORATION
401 Harrison Oaks Boulevard, Suite 250
Cary, North Carolina 27513
Prepared By:
WITHERS & RAVENEL, INC
111 MacKenan Drive
Cary, North Carolina 27511
August 2002
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W&R Project No. 201113
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Kenneth F eq 0.'.
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POND A
Long Lake Subdivision
Tract s

Project Name: Long Lake Subdivision - Tract 1 Project #: 201113.2
Ci State: Raleigh, NC Date: 14-Aug-02
Table 1.1 Surface Area to Drainage Area Ratio for Permanent Pool Sizing for 85% Pollutant
Removal Efficiencv in the Piedmont
% Impervious
Cover Permanent Pool Dept
3.0 4.0 5.0 6.0 h (feet)
7.0 8.0 9.0
10 0.59 0.49 0.43 0.35 0.31 0.29 0.26
20 0.97 0.79 0.70 0.59 0.51 0.46 0.44
30 1.34 1.08 0.97 0.83 0.70 0.64 0.62
40 1.73 1.43 1.25 1.05 0.90 0.82 0.77
50 2.06 1.73 1.50 1.30 1.09 1.00 0.92
60 2.40 2.03 1.71 1.51 1.29 1.18 1.10
70 2.88 2.40 2.07 1.79 1.54 1.35 1.26
80 3.36 2.78 2.38 2.10 1.86 1.60 1.42
90 3.74 3.10 2.66 2.34 2.11 1.83 1.67
Source: NI.UtNK/UWCl Mormwater best management Practices, pg. 5, April 1999
POND A (Constructed Wetland)
Pervious
(ac) Impervious
(ac) Total
Area (ac)
Pervious Area 6.17 0 6.17
Impervious 0 6.05 6.05
Totals 6.17 6.05 12.22
% Impervious. Surface Area = 49.5 %
Surface Area of Permanent Pool:
Assumed depth = 3 feet
SA/DA ratio = 2.04 % from Table 1.1
Minimum pond surface area (SA) _ (DA * SA/DA ratio)/100
SA = 0.250 acres
10878 sq. ft.
Normal pool elevation = 390 feet
Surface area provided = 0.25 acres
10890 sq. ft.
1-Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
Rv = 0.05 + 0.009(1) where, Rv = Runoff coefficient, in./in.
= Percent impervious
Rv = 0.496 in./in.
Total runoff volume from 1-inch precipitation:
Runoff volume, S = (Design rainfall) (Rv) (Drainage Area)
S = 0.505 acre-ft
21983 cu. ft.
Elevation for required storage = 391.76'
Runoff storage provided = 0.505 ac-ft
Riser structure crest elevation - 392 feet
Runoff storage provided .[ij ac-ft
25221 cu. ft.
K:\\01\01-1 10\01 113\HH\SWMP\Pulte Stormwater Calcs Wetlandsjun02.xls
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Job File: K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND A_ TRACTI_WETLAND.PPW
Rain Dir: I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\
JOB TITLE
--------------------------
--------------------------
LONG LAKE SUBDIVISION - TRACT 1
POND A - Extended Detention Wetland
Raleigh, North Carolina
W&R Project #201113.2
The Modified Rational Method was used to determine peak discharge rates for the 2-year,
10-year and 100-year design storm events for the Raleigh/Durham, North Carolina area and
size the detention storage for the dry detention pond due to the small drainage area
(±12.2 acres). The Modified Rational Method is an extension of the rational method for
rainfalls with durations greater than the time of concentration. The method was modified
so that the concepts of the rational method (peak discharge) could be used to develop
hydrographs for storage routing. The Modified Rational Method within PondPack calculates
the storage volume for hydrographs of rainfalls of various durations to determine the
critical duration for the design storm as the one requiring the greatest detention
storage volume. This critical duration is used to calculate the discharge rate and
volume of water that is routed through the pond structure. The hydrograph developed
maintains the calculated volume and adjusts the peak discharge rate accordingly. Thus,
the peak discharge for the Modified Rational Method is less than the calculated Rational
Method.
The rainfall data used in this design was taken from the Intensity-Duration-Frequency
Table for the Raleigh area published in the City of Raleigh Stormwater Management Design
Manual. The post-development time of concentration was set at 5 minutes to account for
the piped drainage system.
Pond A is an extended detention wetland that is designed to capture the volume of runoff
from the first 1-inch of rainfall and slowly release it over a 48 to 72 hour period. In
addition, the wetland is designed to pass the 100-year design storm through the
riser/barrel outlet structure of the pond.
Pond A Design Highlights:
Normal Pool Elevation = 3901
Required Surface Area = 0.250 acres (10,878 sq. ft.)
Surface Area Provided = 0.251 acres (10,940 sq. ft.)
Required Storage Volume '= 0.505 ac-ft
Storage Volume Provided = 0.579 ac-ft at 392,
Top of Dam = 395'
Calculated Freeboard for the 10-yr design storm = 2.39 ft
Calculated Freeboard for the 100-yr design storm = 2.29 ft
Outlet Structure:
¦ 48" RCP Riser structure with crest at 392'
¦ 24" RCP Barrel; 32 linear feet; Inverts at 386.641 and 386'
¦ 2.5" Circular Orifice at 390' for extended draw-down
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Table of Contents
********************** MASTER SUMMARY *********************
Watershed....... Mod. Rational Grand Summary ........ 1.01
Master Network Summary ............. 1.02
*********************w RAINFALL DATA ******************,r****
2-yr IDF Table.. 2-yr
I-D-F Table ........................ 2.01
10-yr IDF Table 10-yr
I-D-F Table ........................ 2.01
100-yr IDF Table 100-yr
I-D-F Table ........................ 2.02
********************** TC CALCULATIONS *********************
AREA POND A..... Tc Calcs ........................... 3.01
*********r************* POND VOLUMES **********************
POND A.......... Vol: Elev-Area 4.01
******************** OUTLET STRUCTURES *********************
OUTLET.......... Outlet Input Data .................. 5.01
Composite Rating Curve ............. 5.04
*********************** POND ROUTING **********************x
POND A.......... Pond E-V-Q Table ................... 6.01
****************** RATIONAL METHOD CALCS *******************
AREA POND A..... C and Area ......................... 7.01
AREA POND A..... Rational Peak Qs ................... 7.02
AREA POND A..... 2-yr Mod. Rational Storm Calcs ..... 7.03
AREA POND A..... 10-yr Mod. Rational Storm Calcs .... 7.04
AREA POND A..... 100-yr Mod. Rational Storm Calcs ... 7.05
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type .... -Mod. Rational Grand Summary Page 1.01
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTl WETLAND.PPW
************************************************************************
* *
* *
* MODIFIED RATIONAL METHOD
* ---- Grand Summary For All Storm Frequencies ----
* *
* *
************************************************************************
************************************************************************
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)

................ Area =
......... 12.220 acres
............
....... Tc
............. = .0833
........ hrs
...........
................ ......... ............ ....... ............. ...................
VOLUMES
Freq. Adjusted Duration I Qpeak Allowable Inflow Storage
years OCT
---------------- hrs
--------- in/hr
------------ cfs
----
- cfs
- ac-ft ac-ft

2 .597
.7167
2.1783 -
16.01 -
--------- --
10.00 I --------
.948 -----------
.618
10 .597 .9167 2.5597 18.82 13.00 I 1.426 .888
100 .597 1.1500 3.2090 23.59 14.00 2.242 1.529
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K.\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTl WETLAND.PPW
MASTER DESIGN STORM SUMMARY
Default Network Design Storm File, ID RAL_IDF.IDQ Raleigh IDF
Rainfall
Return Event Type.
------ IDF File IDF ID
-----
2-yr - ---------------
I-D-F Table -------- --
RAL_IDF --------------
2-yr IDF Table
10-yr I-D-F Table RAL_IDF 10-yr IDF Table
100-yr I-D-F Table RAL_IDF 100-yr IDF Table
MASTER NETWORK SUMMARY
Modified Rational Method Network
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
?lode ID
----------
= Type Event ac-ft Trun
-
---
AREA POND A --- ----
AREA ------
2 ------
----
.948
AREA POND A AREA 10 1.425
AREA POND A AREA 100 2.242
*OUTFALL JCT 2 .661
*OUTFALL JCT 10 1.135
*OUTFALL JCT 100 1.948
POND A IN POND 2 .948
POND A IN POND 10 1.425
POND A IN POND 100 2.241
POND A OUT POND 2 .661
POND A OUT POND 10 1.135
POND A OUT POND 100 1.948
Max
Qpeak Qpeak Max WSEL Pond Storage
hrs
--------- cfs
- ft ac-ft

.0833 -------
16.01 -------- ------------
.0833 18.82
.0833 23.59
.7300 13.66
.9100 18.67
1.1300 23.54
.0900 16.01
.0900 18.82
.0900 23.59
.7300 13.66 392.49 .738
.9100 18.67 392.61 .777
1.1300 23.54 392.73 .816
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... I-D--F Table - Page 2.01
Name.... 2-yr IDF Table Tag: 2-yr Event: 2 yr
C File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
?I Title... 2-yr Storm from City of Raleigh IDF Table
Storm... 2-yr IDF Table Tag: 2-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3330
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
5.7600
4.7600
4.0400
3.4700
2.7000
2.2800
1.9400
1.7000
1.2200
.9500
.7100
.4400
.2600
.1500
Type.... I-D-F Table
Name.... 10-yr IDF Table Tag: 10-yr Event: 10 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL IDF.IDF
Title... 10-yr Event Table from City of Raleigh IDF Table
Storm... 10-yr IDF Table Tag: 10-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833 7.5000
.1670 6.1300
.2500 5.2500
.3300 4.6400
.5000 3.7100
.6670 3.1500
.8330 2.7100
1.0000 2.4100
1.5000 1.7400
2.0000 1.3700
3.0000 1.0200
6.0000 .6500
12.0000 .3900
24.0000 .2200
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... I-D-F Table Page 2.02
Name.... 100-yr IDF Table Tag: 100-yr Event: 100 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL
IDF.IDF
Title... 100-yr Event from City _
of Raleigh IDF Table
Storm... 100-yr IDF Table Tag: 100-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3330
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
9.7200
8.4000
7.2400
6.4700
5.2800
4.4800
3.8800
3.5000
2.5300
2.0000
1.5000
.9600
.5700
.3300
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Tc Calcs
Name.... AREA POND A
Page 3.01
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
TIME OF CONCENTRATION CALCULATOR
Segment #1: Tc: User Defined
Description: Tc = 5 minutes
Segment #1 Time: .0833 hrs
------------------------------------------------------------------------
Total Tc: .0833 hrs
Calculated Tc < Min.Tc:
Use Minimum Tc...
Use Tc = .0833 hrs
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Vol: Elev-Area
Name.... POND A
Page 4.01
File.... K:\01\01-110\01113\H&H\SWMP\PPW-WETLANDS\POND A_TRACTI_WETLAND.PPW
Elevation Planimeter Area Al+A2+sgr(Al*A2) Volume Volume Sum
(ft)
------ (sq.in) (acres)
---------------------- (acres)
---------------- (ac-ft)
---------- (ac-ft)
-------------
-----
390.00 ----- .2500 .0000 .000 .000
391.00 ----- .2950 .8166 .272 .272
392.00 ----- .3190 .9208 .307 .579
393.00 ----- .3420 .9913 .330 .910
394.00 ----- .3900 1.0972 .366 1.275
395.00 ----- .4260 1.2236 .408 1.683
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
volume, = Incremental volume between EL1 and EL2
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Outlet Input Data Page 5.01
Name.... OUTLET
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 390.00 ft
Increment .10 ft
Max. Elev.= 395.00 ft
**********************************************
OUTLET CONNECTIVITY
**********************************************
---> Forward Flow Only (UpStream to DnStream)
<--- Reverse Flow Only (DnStream to UpStream)
< --- > Forward and Reverse Both Allowed
Structure No. Outfall E1, ft E2, ft
Stand Pipe RI ---> CV 392.000 395.000
Orifice-Circular OR ---> CV 390.000 395.000
Culvert-Circular CV ---> TW 388.000 395.000
TW SETUP, DS Channel
LONG LAKE-SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Outlet Input Data
Name.... OUTLET
Page 5.02
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = RI
Structure Type = Stand Pipe
-----------------
# of openings -------------
= 1 ------
Invert Elev. _ 392.00 ft
Diameter = 4.0000 ft
orifice Area = 12.5664 sq.ft
Orifice Coeff. _ .600
Weir Length = 12.57 ft
Weir Coeff. = 3.100
K, Submerged = .000
K, Reverse = 1.000
Kb,Barrel = .000000 (per ft of full flow)
Barrel Length = .00 ft
Mannings n = .0000
Structure ID = OR
Structure Type = Orifice-Circular
------------------------------------
# of openings = 1
Invert Elev. = 390.00 ft
Diameter = .2083 ft
Orifice Coeff. _ .600
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Outlet Input Data
Name.... OUTLET
Page 5.03V-Gv
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = CV
Structure Type
----------------- = Culvert-Circular
-------------------
No. Barrels = 1
Barrel Diameter = 2.0000 ft
Upstream Invert = 388.00 ft
Dnstream Invert = 387.50 ft
Horiz. Length = 150.00 ft
Barrel Length = 150.00 ft
Barrel Slope = .00333 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .5000
Kb = .012411
Kr = .5000
HW Convergence = .001
(forward entrance loss)
(per ft of full flow)
(reverse entrance loss)
+/- ft
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0098
Inlet Control M = 2.0000
Inlet Control c _ .03980
Inlet Control Y = .6700
T1 ratio (HW/D) = 1.158
T2 ratio (HW/D) = 1.305
Slope Factor = -.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 390.32 ft ---> Flow = 15.55 cfs
At T2 Elev = 390.61 ft ---> Flow = 17.77 cfs
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFALL CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES...
Maximum Iterations= 30
Min. TW tolerance = .01 ft
Max. TW tolerance = .01 ft
Min. HW tolerance = .01 ft
Max. HW tolerance = .01 ft
Min. Q tolerance = .10 cfs
Max. Q tolerance = .10 cfs
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Composite Rating Curve
Name.... OUTLET
Page 5 . 04 2-c v
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q Notes
-------- -------- ----- --- Converge
-------
----
--
------------
Elev. Q TW Elev Error
ft
-----=-- cfs
------- ft +/-ft
---
--
-- Contributing Structures

390.00
.00 --
Free - --
-
Outfall --------
(no Q: ------
RI,OR ------------
,CV)
390.10 .01 Free Outfall OR,CV (no. Q: RI).
390.20 .05 Free Outfall OR,CV (no Q: RI)
390.30 .07 Free Outfall OR,CV (no Q: RI)
390.40 .09 Free Outfall OR,CV (no Q: RI)
390.50 .10 Free Outfall OR,CV (no Q: RI)
390.60 .12 Free Outfall OR,CV (no Q: RI)
390.70 .13 Free Outfall OR,CV (no Q: RI)
390.80 .14 Free Outfall OR,CV (no Q: RI)
390.90 .15 Free Outfall OR,CV (no Q: RI)
391.00 .16 Free Outfall OR,CV (no Q: RI)
391.10 .16 Free Outfall OR,CV (no Q: RI)
391.20 .17 Free Outfall OR,CV (no Q: RI).
391.30 .18 Free Outfall OR,CV (no Q: RI)
391.40 .19 Free Outfall OR,CV (no Q: RI)
391.50 .19 Free Outfall OR,CV (no Q: RI)
391.60 .20 Free Outfall OR,CV (no Q: RI)
391.70 .21 Free Outfall OR,CV (no Q: RI)
391.80 .21 Free Outfall OR,CV (no Q: RI)
391.90 .22 Free Outfall OR,CV (no Q: RI)
392.00 .23 Free Outfall OR,CV (no Q: RI)
392.10 1.46 Free Outfall RI,OR,C V
392.20 3.72 Free Outfall RI,OR,C V
392.30 6.64 Free Outfall RI,OR,C V
392.40 10.10 Free Outfall RI,OR,C V
392.50 14.02 Free Outfall RI,OR,C V
392.60 18.31 Free Outfall RI,OR,C V
392.70 22.94 Free Outfall RI,CV (no Q: OR)
392.80 25.33 Free Outfall RI,CV (no Q: OR)
392.90 25.70 Free Outfall RI,CV (no Q: OR)
393.00 26.05 Free Outfall RI,CV (no Q: OR)
393.10 26.39 Free Outfall RI,CV (no Q: OR)
393.20 26.74 Free Outfall RI,CV (no Q: OR)
393.30 27.07 Free Outfall RI,CV (no Q: OR)
393.40 27.41 Free Outfall RI,CV (no Q: OR)
393.50 27.74 Free Outfall RI,CV (no Q: OR)
393.60 28.07 Free Outfall RI,CV (no Q: OR)
393.70 28.39 Free Outfall RI,CV (no Q: OR)
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Composite Rating Curve
Name.... OUTLET
Page 5.05 ezV
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q
Elev. Q
ft
------- cfs
-
393.80 -------
28.71.
393.90 29.03
394.00 29.35
394.10 29.66
394.20 29.96
394.30 30.27
394.40 30.58
394.50 30.88
394.60 31.18
394.70 31..47
394.80 31.76
394.90 32.06
395.00 32.35
Notes
-------- Converge -------------------------
ft +/-ft
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Free Outfall
Contributing Structures
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
RI,CV (no Q: OR)
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Pond E-V-Q Table Page 6.01 Qjew
Name.... POND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\
Inflow HYG file = NONE STORED - POND A IN 2-yr
Outflow HYG file = NONE STORED - POND A OUT 2-yr
Pond Node Data = POND A
Pond Volume Data = POND A
Pond Outlet Data = OUTLET
No Infiltration
INITIAL CONDITIONS
---------
Starting -----------
WS Elev = ----------
390.00 ----
ft
Starting Volume = .000 ac-ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + 0
ft
--- cfs ac-ft acres cfs cfs cfs
---------
390.00 ------------
.00 ---------
.000 ------------
.2500 -----------
.00 ------------
.00 ----------
.00
390.10 .01 .025 .2543 .00 .01 61.04
390.20 .05 .051 .2587 .00 .05 123.16
390.30 .07 .077 .2631 .00 .07 186.30
390.40 .09 .103 .2676 .00 .09 250.53
390.50 .10 .130 .2720 .00 .10 315.84
390.60 .12 .158 .2766 .00 .12 382.24
390.70 .13 .186 .2811 .00 .13 449.73
390.80 .14 .214 .2857 .00 .14 518.30
390.90 .15 .243 .2903 .00 .15 588.02
391.00 .16 .272 .2950 .00 .16 658.85
391.10 .16 .302 .2974 .00 .16 730.54
391.20 .17 .332 .2997 .00 .17 802.80
391.30 .18 .362 .3021 .00 .18 875.61
391.40 .19 .392 .3045 .00 .19 949.02
391.50 .19 .423 .3069 .00 .19 1023.01
391.60 .20 .453 .3093 .00 .20 1097.58
391.70 .21 .485 .3117 .00 .21 1172.73
391.80 .21 .516 .3141 .00 .21 1248.44
391.90 .22 .547 .3166 .00 .22 1324.76
392.00 .23 .579 .3190 .00 .23 1401.68
392.10 1.46 .611 .3213 .00 1.46 1480.39
392.20 3.72 .643 .3235 .00 3.72 1560.67
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Pond E-V-Q Table Page 6.02 Rev
Name.... POND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\
Inflow HYG file = NONE STORED - POND A IN 2-yr
Outflow HYG file = NONE STORED - POND A OUT 2-yr
Pond Node Data = POND A
Pond Volume Data = POND A
Pond Outlet Data = OUTLET
No Infiltration
INITIAL CONDITIONS
--------
Starting ------------
WS Elev = ---------
390.00 -----
ft
Starting Volume = .000 ac-ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + 0
ft
------------ cfs
--- ac-ft acres cfs cfs cfs

392.30 ---------
6.64 ---------
.676 ------------
.3258 -----------
.00 ------------
6.64 ----------
1642.15
392.40 10.10 .709 `.3281 .00 10.10 1724.74
392.50 14.02 .741 .3304 .00 14.02 1808.34
392.60 18.31 .775 .3327 .00 18.31 1892.87
392.70 22.94 .808 .3350 .00 22.94 1978.29
392.80 25.33 .842 .3373 .00 25.33 2062.02
392.90 25.70 .875 .3397 .00 25.70 2144.32
393.00 26.05 .910 .3420 .00 26.05 2227.15
393.10 26.39 .944 .3467 .00 26.39 2310.82
393.20 26.74 .979 .3513 .00 26.74 2395.63
393.30 27.07 1.014 .3561 .00 27.07 2481.54
393.40 27.41 1.050 .3608 .00 27.41 2568.63
393.50 27.74 1.086 .3656 .00 27.74 2656.86
393.60 28.07 1.123 .3704 .00 28.07 2746.25
393.70 28.39 1.161 .3753 .00 28.39 2836.81
393.80 28.71 1.198 .3801 .00 28.71 2928.52
393.90 29.03 1.237 .3851 .00 29.03 3021.43
394.00 29.35 1.275 .3900 .00 29.35 3115.53
394.10 29.66 1.314 .3935 .00 29.66 3210.66
394.20 29.96 1.354 .3971 .00 29.96 3306.63
394.30 30.27 1.394 .4006 .00 30.27 3403.44
394.40 30.58 1.434 .4042 .00 30.58 3501.14
394.50 30.88 1.475 .4078 .00 30.88 3599.70
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Pond E-V-Q Table Page 6.03 pl
Name.... POND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTl WETLAND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\
Inflow HYG file = NONE STORED - POND A IN 2-yr
Outflow HYG file = NONE STORED - POND A OUT 2-yr
Pond Node Data = POND A
Pond Volume Data = POND A
Pond Outlet Data = OUTLET
No Infiltration
INITIAL CONDITIONS
Starting WS Elev = 390.00 ft
Starting Volume = .000 ac- ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + 0
ft
------------ cfs ac-ft acres cfs cfs cfs

394.60 ------------
31.18 ---------
1.516 ---- --------
.4114 -----------
.00 ------------
31.18 ----------
3699.13
394.70" 31.47 1.557 .4150 .00 31.47 3799.42
394.80 31.76 1.599 .4187 .00 31.76 3900.57
394.90 32.06 1.641 .4223 .00 32.06 4002.63
395.00 32.35 1.683 .4260 .00 32.35 4105.57
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... C and Area Page 7.01
Name.... AREA POND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND A_TRACTl WETLAND.PPW
RATIONAL C COEFFICIENT DATA
.........................................................................
.........................................................................
Area C x Area
Soil/Surface Description C acres acres
-------------------------------- -------- ---------- ----------
Impervious Area .9500 6.050 5.748
Pervious Area .2500 6.170 1.543
WEIGHTED C & TOTAL AREA ---> .5966 12.220 7.290
.........................................................................
.........................................................................
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Rational Peak Q's Page 7.02
Name.... POST QPEAK
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND A TRACTI WETLAND.PPW
SUMMARY OF RATIONAL METHOD PEAK DISCHARGES
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
Rational Storms: RAL_ IDF.IDQ Raleigh IDF
Tag
---- Freq File IDF Curve
-
100-yr ------
100 ------
RAL_ID ------
F.IDF -----------
100-yr IDF -----
Table
Tc = .0833 hrs

Tag
Freq
C
C adj ----------
j C --------
I -----------
Area

----- (years)
------
-
- factor final in/hr acres

1-yr
1 -
--
.597 ------
1.000 ----------
.597 --------
4.6080 -----------?
12.220
10-yr 10 .597 1.000 .597 7.5000 12.220
100-yr 100 .597 1.000 .597
---------- 9.7200
-------- 12.220
-----------
Peak Q
cfs
33.87
55.13
71.45
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Mod. Rational Storm Calcs Page 7.03
Name.... AREA POND A Tag: 2-yr Event: 2 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND A_TRACTI_WETLAND.PPW
Storm... 2-yr IDF Table Tag: 2-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 2 yr 'C' Adjustment = 1.000Allowable Q = 10.00 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .7167 hrs Tc = .0833 hrs
Hydrograph File: 2-yr
.
:::
. ....
::::::
. ...
::
... . ..
.
................. .....
. .
.... .
::... ...:::::.:.. .:::::VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'C' 'C'
----------------- hrs
--- in/hr acres cfs ac-ft ac-ft

.597 .597 ------
.0833 -----------
5.7600 --------
12.220 --------- --
42.34 I ----------
.292 ---------
.223
.597 .597 .1667 4.7640 12.220 35.02 .482 .379
.597 .597 .2500 4.0400 12.220 29.70 I .614 .476
.597 .597 .3333 3.4685 12.220 25.50 I .702 .530
.597 .597 .5000 2.7000 12.220 19.85 .820 .579
.597 .597 .6667 2.2808 12.220 16.77 ( .924 .614
************************************************************ Storage Maximum
.597 .597 .7167 2.1783 12.220 16.01 .948 .618
****************************************************************************
.597 .597 .8333 1.9395 12.220 14.26 .982 .603
.597 .597 1.0000 1.7000 12.220 12.50 I 1.033 .585
.597 .597 2.0000 .9500 12.220 6.98 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Mod. Rational Storm Calcs Page 7.04
Name.... AREA POND A Tag: 10-yr Event: 10 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND A_TRACTI_WETLAND.PPW
Storm... 10-yr IDF Table Tag: 10-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN
------- FREQUENCY:
---------- 10 yr 'C' Adjustment = 1.000Allowable
---------------------------------------- Q = 13.00
----------- cfs
--------
Hydrograph Storm Duration, Td = .9167 hrs Tc = .0833 hrs
Hydrograph File: 10-yr
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'C'
------- 'C'
---------- hrs
--------- in/hr
------
---- acres cfs ac-ft ac-ft

.597
.597
.0833 -
-
7.5000 -------
12.220 --------- --
55.13 I -----------
.380 --------
.290
.597 .597 .1667 6.1355 12.220 45.10 .621 .487
.597 .597 .2500 5.2500 12.220 38.59 I .797 .618
.597 .597 .3333 4.6218 12.220 33.98 .936 .712
.597 .597„ .5000 3.7100 12.220 27.27 1.127 .814
.597 .597 .6667 3.1511 12.220 23.16 ( 1.276 .873
.597 .597 .8333 2.7094 12.220 19.92 1.372 .879
***************** ******************************************* Storage Maximum
597 .597 .9167 2.5597 12.220 18.82 I 1.426 .888
***************** *************************************************** ********
.597 .597 1.0000 2.4100 12.220 17.72 1.464 .882
.597 .597 2.0000 1.3700 12.220 10.07 I Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Type.... Mod. Rational Storm Calcs Page 7.05
Name.... AREA POND A Tag: 100-yr Event: 100 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND A TRACTI_WETLAND.PPW
Storm... 100-yr IDF Table Tag: 100-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN
------ FREQUENCY:
----------- 100 yr
--------- 'C' Adjustment =
------------------ 1.000Allowable
-------------- Q = 14.00
----------- cfs
-------
Hydrograph Storm Duration, Td = 1.1500 hrs Tc = .0833 hrs
Hydrograph File: 100-yr
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'C'
------- 'C'
---------- hrs
--------- in/hr
-- acres cfs ac-ft ac-ft

.597
.597
.0833 ----------
9.7200 ------
12.220 ---------- ---
71.45 I -----------
.492 -------
.395
.597 .597 .1667 8.4053 12.220 61.79 I .851 .706
.597 .597 .2500 7.2400 12.220 53.22 I 1.100 .907
.597 .597 .3333 6.4676 12.220 47.54 I 1.310 1.069
.597 .597 .5000 5.2800 12.22.0 38.81 I 1.604 1.266
.597 .597 .6667 4.4816 12.220 32.95 I 1.815 1.381
.597 .597 .8333 3.8792 12.220 28.52 I 1.964 1.434
.597 .597 1.0000 3.5000 12.220 25.73 2.126 1.500
************************************************************ Storage Maximum
.597 .597 1.1500 3.2090 12.220 23.59 2.242 1.529
****************************************************************************
597 .597 2.0000 2.0000 12.220 14.70 I 2.430 1.225
597 .597 3.0000 1.5000 12.220 11.03 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Elev. ?s. Flow
STAGE-DISCHARGE FUNCTION FOR OUTLET
1?
w
w
LL
Plotted Curves
OUTLET
Plotted Curves
WETLAND IN 1-yr
WETLAND OUT 1-yr
0 10 20 30 40
Flow (cfs)
Hydrograph for 1-year Design Storm
WETLAND IN vs OUT
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Hydrograph for 10-yr Design Storm
WETLAND IN vs OUT
3
0
LL
Hydrograph for 100-yr Design Storm
WETLAND IN \s OUT
w
0
LL
Plotted Curves
WETLAND IN 10-yr
WETLAND OUT 10-yr
Plotted Curves
WETLAND IN 100-yr
WETLAND OUT 100-yr
0.0 0,5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
LONG LAKE SUBDIVISION - TRACT 1
POND A - PONDPACK OUTPUT FOR WETLAND DESIGN
Volume ks Time
MINIMUM DRAIN TIME- Runoff from first 1" Rainfall
:?
E
0
Plotted Curves
MIN DRAIN OUT
0 10 20 30 40 50 60 70 80
Time (hrs)
Project Name: Long Lake Subdivision - Tract 1 Project #: 201113.2
Ci /State: Raleigh, NC Date: 13-Aug-02
Table 1.1 Surface Area to Drainage Area Ratio for Permanent Pool Sizing for 85% Pollutant
Removal Efficiencv in the Piedmont
% Impervious
Cover Permanent Pool Depth (feet)
3.0 4.0 5.0 6.0 7.0 8.0 9.0
10 0.59 0.49 0.43 0.35 0.31 0.29 0.26
20 0.97 0.79 0.70 0.59 0.51 0.46 0.44
30 1.34 1.08 0.97 0.83 0.70 0.64 0.62
40 1.73 1.43 1.25 1.05 0.90 0.82 0.77
50 2.06 1.73 1.50 1.30 1.09 1.00 0.92
60 2.40 2.03 1.71 1.51 1.29 1.18 1.10
70 2.88 2.40 2.07 1.79 1.54 1.35 1.26
L 80 3.36 2.78 2.38 2.10 1.86 1.60 1.42
90 3.74 3.10 2.66 2.34 2.11 1.83 1.67
Source: NCDENR/DWQ Stormwater Best Management Practices, pg. 5, April 1999
POND C - TRACT 1, PHASES 3 & 4 (Constructed Wetland)
Pervious
(ac) Impervious
(ac) Total
Area (ac)
FES #45A 4.79 173 7.52

% Impervious Surface'Area = 36 %
Surface Area of Permanent Pool:
Assumed depth = 3 feet
SA/DA ratio = 1.57 % From Table 1.1
Minimum pond surface area (SA) = ( DA * SA/DA ratio)/100
SA = 0.118 acres
5156 sq. ft.

Normal pool elevation = 396 feet
Surface area provided = 0.123: r acres
5342 sq. ft.
1-Inch. Runoff Volume Calculation
II Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
Rv = 0.05 + 0.009(1) where, Rv = Runoff coefficient, in./in.
= Percent impervious
Rv = 0.38 in./in.
Total runoff volume from 1-inch precipitation:
Runoff volume, S = (Design rainfall) (Rv) (Drainage Area)
S = 0.236 acre-ft
10284 cu. ft.
Riser structure crest elevation = 398 feet
Runoff storage provided = .a _: ac-ft
12232 cu. ft.
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Job File: K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
Rain Dir: I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\
--------------------------
--------------------------
JOB TITLE
LONG LAKE SUBDIVISION - TRACT 1
Pond C - Tract 1, Phases 3 & 4
Constructed Wetland Design
Raleigh, North Carolina
W&R Project #201113.2
The Modified Rational Method was used to determine peak discharge rates for the 2-year,
10-year and 100-year design storm events for the Raleigh/Durham, North Carolina area and
size the detention storage for the dry detention pond due to the small drainage area
(±7.5 acres). The Modified Rational Method is an extension of the rational method for
rainfalls with durations greater than the time of concentration. The method was modified
so that the concepts. of the rational method (peak discharge) could be used to develop
hydrographs for storage routing. The Modified Rational Method within PondPack calculates
the storage volume for hydrographs of rainfalls of various durations to determine the
critical duration for the design storm as the one requiring the greatest detention
storage volume. This critical duration is used to calculate the discharge rate and
volume of water that is routed through the pond structure. The hydrograph developed
maintains the calculated volume and adjusts the peak discharge rate accordingly. Thus,
the peak discharge for the modified Rational Method is less than the calculated Rational
Method.
I The rainfall data used in this design was taken from the Intensity-Duration-Frequency
III Table for the Raleigh area published in the City of Raleigh Stormwater Management Design
Manual. The post-development time of concentration was set at 5 minutes to account for
the piped drainage system.
Pond C is an extended detention wetland that is designed to capture the volume of runoff
from the first 1-inch of rainfall and slowly release it over a 48 to 72 hour period. In
addition, the wetland is designed to pass the 100-year design storm through the
1 riser/barrel outlet structure of the pond.
Pond C Design Summary:
Normal Pool Elevation = 3961
Required Surface Area = 0.118 acres (5156 sq ft)
Surface Area Provided = 0.123 acres (5342 sq ft)
Required Storage Volume = 0.236 ac-ft (10,280 cu ft)
Storage Volume Provided = 0.281 ac-ft (12,232 cu ft)
Top of Dam = 400.5'
Calculated Freeboard for the 10-yr design storm = 1.9 ft
Calculated Freeboard for the 100-yr design storm = 1.2 ft
Outlet Structure:
¦ 4811 RCP Riser structure with crest at 398'
¦ 15" RCP Barrel; 94 ft length; Inverts at 394.5' and 394'
¦ Floating Skimmer device with constant Q = 0.06 cfs for draw-down
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Table of Contents
***********r********** MASTER SUMMARY **********************
Watershed....... Mod. Rational Grand Summary ........ 1.01
Master Network Summary ............. 1.02
I ********************** RAINFALL DATA ***********************
2-yr IDF Table.. 2-yr
I-D-F Table ........................ 2.01
10-yr IDF Table 10-yr
I-D-F Table ........................ 2.01
100-yr IDF Table 100-yr
I-D-F Table ........................ 2.02
********************** TC CALCULATIONS *********************
AREA POND C..... Tc Calcs ........................... 3.01
**r********r**r******** POND VOLUMES ******tt***************
WETLAND......... Vol: Elev-Area ..................... 4.01
******************** OUTLET STRUCTURES *********************
OUTLET POND C... Outlet Input Data .................. 5.01
Composite Rating Curve ............. 5.04
*********************** POND ROUTING ***********************
WETLAND......... Pond E-V-Q Table ................... 6.01
****************** RATIONAL METHOD CALCS *******************
AREA POND C..... C and Area ......................... 7.01
AREA POND C..... Rational Peak Qs .................... 7.02
AREA POND C..... 2-yr Mod. Rational Storm Calcs ..... 7.03
AREA POND C..... 10-yr Mod. Rational Storm Calcs .... 7.04
AREA POND C..... 100-yr Mod. Rational Storm Calcs ... 7.05
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Mod. Rational Grand Summary Page 1.01
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
************************************************************************
* *
* *
* MODIFIED RATIONAL METHOD
* ---- Grand Summary For All Storm Frequencies ----
* *
************************************************************************
************************************************************************
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
Area =, 7.520 acres Tc = .0833 hrs
VOLUMES
Freq. Adjusted Duration I Qpeak Allowable Inflow Storage
years 'C'
---------------- hrs
------- in/hr cfs cfs I ac-ft ac-ft

2 .503 --
.6000 -----------
2.4485 --------
9.34 ---------- ---
7.00 I --------
.463 ----------
.266
10 .503 .5833 3.4306 13.09 11.00 I .631 .328
100 .503 .7333 4.2402 16.18 12.00 .981 .576
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
MASTER DESIGN STORM SUMMARY
Default Network Design Storm File, ID RAL_IDF.IDQ Raleigh IDF
Rainfall
Return Event Type
------------ --------- IDF File IDF ID

2-yr ------
I-D-F Table -------- --
RAL_IDF --------------
2-yr IDF Table
10-yr I-D-F Table RAL IDF 10-yr IDF Table
100-yr I-D-F Table RAL_IDF 100-yr IDF Table
MASTER NETWORK SUMMARY
Modified Rational Me thod Network
(*Node=Outfall; +Node =Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
Node ID
------------- Type
---- ='-- Event ac-ft Trun

AREA POND C -
AREA ------
2 ----------
.463
AREA POND C AREA 10 .631
AREA POND C AREA 100 .981
*OUTFALL JCT 2 .275
*OUTFALL JCT 10 .443
*OUTFALL JCT 100 .791
WETLAND IN POND 2 .463
WETLAND IN POND 10 .631
WETLAND IN POND 100 .980
WETLAND OUT POND 2 .275
WETLAND OUT POND 10 .443
WETLAND OUT POND 100 .791
Max
Qpeak Qpeak Max WSEL Pond Storage
hrs
--------- cfs
------- ft ac-ft

.0833 -
9.34 -------- ------------
.0833 13.09
.0833 16.18
.6000 8.75
.5900 11.21
.7500 12.34
.0900 9.34
.0900 13.09
.0900 16.18
.6000 8.75 398.37 .340
.5900 11.21 398.60 .380
.7500 12.34 399.30 .503
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... I-D-F Table Page 2.01
Name.... 2-yr IDF Table Tag: 2-yr Event: 2 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL
IDF.IDF
Title... 2-yr Storm from _
City of Raleigh IDF Table
Storm... 2-yr IDF Table Tag: 2-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3330
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
5.7600
4.7600
4.0400
3.4700
2.7000
2.2800
1.9400
1.7000
1.2200
.9500
.7100
.4400
.2600
.1500
Type.... I-D-F Table
Name.... 10-yr IDF Table Tag: 10-yr Event: 10 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL IDF.IDF
Title... 10-yr Event Table from City of Raleigh IDF Table
Storm... 10-yr IDF Table Tag: 10-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833 7.5000
.1670 6.1300
.2500 5.2500
.3300 4.6400
.5000 3.7100
.6670 3.1500
.8330 2.7100
1.0000 2.4100
1.5000 1.7400
2.0000 1.3700
3.0000 1.0200
6.0000 .6500
12.0000 .3900
24.0000 .2200
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... I-D-F Table Page 2.02
?i Name.... 100-yr IDF Table Tag: 100-yr Event: 100 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
Title... 100-yr Event from City of Raleigh IDF Table
Storm... 100-yr IDF Table Tag: 100-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3330
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
9.7200
8.4000
7.2400
6.4700
5.2800
4.4800
3.8800
3.5000
2.5300
2.0000
1.5000
.9600
.5700
.3300
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Tc Calcs Page 3.01
i Name.... AREA POND C
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
.... ... . ..........................
TIME OF CONCENTRATION CALCULATOR
Segment #1: Tc: User Defined
Description: Time of Concentration = 5 minutes
Segment #1 Time: .0833 hrs
------------------------------------------------------------------------
-------------------------
-------------------------
Total Tc: .0833 hrs
Calculated Tc < Min.Tc:
Use Minimum Tc...
Use Tc = .0833 hrs
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Vol: Elev-Area
Name.... WETLAND
Page 4.01
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft)
------------ (sq.in) (acres)
--------------------- (acres)
------ (ac-ft) (ac-ft)

396.00
----- .1230 -----------
.0000 ---------
.000 -------------
.000
397.00 ----- .1400 .3942 .131 .131
398.00 ----- .1590 .4482 .149 .281
399.00 ----- .1780 .5052 .168 .449
400.00 ----- .1970 .5623 .187 .637
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Area2))
where: ELI, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for ELI, EL2, respectively
Volume = Incremental volume between ELI and EL2
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Outlet Input Data Page 5.01
Name.... OUTLET POND C
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 396.00 ft
Increment = .10 ft
Max. Elev.= 400.00 ft
OUTLET CONNECTIVITY
---> Forward Flow Only (UpStream to DnStream)
<--- Reverse Flow Only (DnStream to UpStream)
< --- > Forward and Reverse Both Allowed
Structure No. Outfall E1, ft E2, ft
----------------- ---- ------- --------- ---------
User Defined Table SK ---> TW .000 400.000
Stand Pipe RI ---> CV 398.000 400.000
Culvert-Circular CV ---> TW 394.500 400.000
TW SETUP, DS Channel
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Outlet Input Data Page 5.02
Name.... OUTLET POND C
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = SK
Structure Type = User Defined Table
------------------------------------
ELEV-FLOW RATING TABLE
Elev, ft Flow, cfs
--------- ---------
396.00 .06
400.00 .06
Structure ID = RI
Structure Type
----------------- = Stand Pipe
-

# of openings ------------
= 1 ------
Invert Elev. = 398.00 ft
Diameter = 4.0000 ft
orifice Area = 12.5664 sq.ft
Orifice Coeff. _ .600
Weir Length = 12.57 ft
Weir Coeff. = 3.100
K, Submerged = .000
K, Reverse = 1.000
Kb,Barrel = .000000 (per ft of full flow)
Barrel Length = .00 ft
Mannings n = .0000
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Outlet Input Data
I Name.... OUTLET POND C
Page 5.03
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4 WETLAND.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = CV
Structure Type = Culvert-Circular
------------------------------------
No. Barrels = 1
Barrel Diameter = 1.2500 ft
Upstream Invert = 394.50 ft
Dnstream Invert = 390.50 ft
Horiz. Length = 94.00 ft
Barrel Length = 94.09 ft
Barrel Slope = .04255 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .5000
Kb = .023225
Kr = .5000
HW Convergence = .001
(forward entrance loss)
(per ft of full flow)
(reverse entrance loss)
+/- ft
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0098
Inlet Control M = 2.0000
Inlet Control c = .03980
Inlet Control Y = .6700
T1 ratio (HW/D) = 1.139
T2 ratio (HW/D) = 1.286
Slope Factor = -.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1-& T2...
At T1 Elev = 395.92 ft ---> Flow = 4.80 cfs
At T2 Elev = 396.11 ft ---> Flow = 5.49 cfs
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFALL CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES...
l Maximum Iterations= 30
Min. TW tolerance = .01 ft
Max. TW tolerance = .01 ft
Min. HW tolerance = .01 ft
Max. HW tolerance = .01 ft
Min. Q tolerance = .10 cfs
Max. Q tolerance = .10 cfs
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Composite Rating Curve
Name.... OUTLET POND C
Page 5.04
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q Notes
-------- -------- ----- --- Converge
----------
---------------
Elev. Q TW Elev Error
ft
-------- cfs
----- ft +/-ft Contributing Structures

396.00 --
.06 -----
Free --- -----
Outfall -----------
SK (no Q: ---------------
RI,CV)
396.10 .06 Free Outfall SK (no Q: RI,CV)
396.20 .06 Free Outfall SK (no Q: RI,CV)
396.30 .06 Free Outfall SK (no Q: RI,CV)
396.40 .06 Free Outfall SK (no Q: RI,CV)
396.50 .06 Free Outfall SK (no Q: RI,CV)
396.60 .06 Free Outfall SK (no Q: RI,CV)
396.70 .06 Free Outfall SK (no Q: RI,CV)
396.80 .06 Free Outfall SK (no Q: RI,CV)
396.90 .06 Free Outfall SK (no Q: RI,CV)
397.00 .06 Free Outfall SK (no Q: RI,CV)
397.10 .06 Free Outfall SK (no Q: RI,CV)
397.20 .06 Free Outfall SK (no Q: RI,CV)
397.30 .06 Free Outfall SK (no Q: RI,CV)
397.40 .06 Free Outfall SK (no Q: RI,CV)
397.50 .06 Free Outfall SK (no Q: RI,CV)
397.60 .06 Free Outfall SK (no Q: RI,CV)
397.70 .06 Free Outfall SK (no Q: RI,CV)
397.80 .06 Free Outfall SK (no Q: RI,CV)
397.90 .06 Free Outfall SK (no Q: RI,CV)
398.00 .06 Free Outfall SK (no Q: RI,CV)
398.10 1.29 Free Outfall SK,RI,CV
398.20 3.54 Free Outfall SK,RI,CV
398.30 6.46 Free Outfall SK,RI,CV
398.40 9.91 Free Outfall SK,RI,CV
398.50 11.05 Free Outfall SK,RI,CV
398.60 11.22 Free Outfall SK,RI,CV
398.70 11.38 Free Outfall SK,RI,CV
398.80 11.55 Free Outfall SK,RI,CV
398.90 11.71 Free Outfall SK,RI,CV
399.00 11.87 Free Outfall SK,RI,CV
399.10 12.03 Free Outfall SK,RI,CV
399.20 12.19 Free Outfall SK,RI,CV
399.30 12.34 Free Outfall SK,RI,CV
399.40 12.50 Free Outfall SK,RI,CV
399.50 12.65 Free Outfall SK,RI,CV
399.60 12.80 Free Outfall SK,RI,CV
399.70 12.95 Free Outfall SK,RI,CV
399.80 13.09 Free Outfall SK,RI,CV
399.90 13.24 Free Outfall SK,RI,CV
400.00 13.38 Free Outfall SK,RI,CV
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C.- PONDPACK OUTPUT
Type.... Pond E-V-Q Table Page 6.01
Name.... WETLAND
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\
Inflow HYG file = NONE STORED - WETLAND IN 2-yr
Outflow HYG file = NONE STORED - WETLAND OUT 2-yr
Pond Node Data = WETLAND
Pond Volume Data = WETLAND
Pond Outlet Data = OUTLET POND C
No Infiltration
INITIAL CONDITIONS
--------
Starting ------------
WS Elev = ---------
396.00 ----
ft -
Starting Volume = .000 ac- ft
Starting Outflow = .06 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .06 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + 0
ft
------------- cfs
-- ac-ft acres cfs cfs cfs

396.00 ---------
.06 ---------
.000 ---- --------
.1230 -----------
.00 ------------
.06 ----------
.06
396.10 .06 .012 .1247 .00 .06 30.03
396.20 .06 .025 .1263 .00 .06 60.40
396.30 .06 .038 .1280 .00 .06 91.16
396.40 .06 .051 .1297 .00 .06 122.34
396.50 .06 .064 .1314 .00 .06 153.92
396.60 .06 .077 .1331 .00 .06 185.92
396.70 .06 .090 .1348 .00 .06 218.33
396.80 .06 .104 .1365 .00 .06 251.15
396.90
II .06 .117 .1383 .00 .06 284.40
I
397.00 .06 .131 .1400 .00 .06 318.07
397.10 .06 .146 .1418 .00 .06 352.17
397.20 .06 .160 .1437 .00 .06 386.73
397.30 .06 .174 .1456 .00 .06 421.72
397.40 .06 .189 .1475 .00 .06 457.18
397.50 .06 .204 .1493 .00 .06 493.09
397.60 .06 .219 .1513 .00 .06 529.47
397.70 .06 .234 .1532 .00 .06 566.31
397.80 .06 .249 .1551 .00 .06 603.60
397.90 .06 .265 .1570 .00 .06 641.37
398.00 .06 .281 .1590 .00 .06 679.61
398.10 1.29 .297 .1609 .00 1.29 719.55
j 398.20 3.54 .313 .1627 .00 3.54 760.96
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
Q POND C - PONDPACK OUTPUT
Type.... Pond E-V-Q Table Page 6.02
Name.... WETLAND
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\
Inflow HYG file = NONE STORED - WETLAND IN 2-yr
Outflow HYG file = NONE STORED - WETLAND OUT 2-yr
Pond Node Data = WETLAND
Pond Volume Data = WETLAND
Pond Outlet Data = OUTLET POND C
No Infiltration
INITIAL CONDITIONS
--------
Starting -------------
WS Elev = --------
396.00 -----
ft
Starting Volume = .000 ac-ft
Starting Outflow = .06 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .06 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + O
ft
------------- cfs
---- ac-ft acres cfs cfs cfs

398.30 --------
6.46 --------
.329 ------------
.1646 -----------
.00 ------------
6.46 ----------
803.47
398.40 9.91 .346 .1665 .00 9.91 846.98
398.50 11.05 .363 .1684 .00 11.05 888.63
398.60 11.22 .380 .1703 .00 11.22 929.78
398.70 11.38 .397 .1722 .00 11.38 971.39
398.80 11.55 .414 .1741 .00 11.55 1013.44
398.90 11.71 .432 .1761 .00 11.71 1055.98
399.00 11.87 .449 .1780 .00 11.87 1098.98
` 399.10 12.03 .467 .1799 .00 12.03 1142.45
399.20 12.19 .485 .1817 .00 12.19 1186.36
399.30 12.34 .503 .1836 .00 12.34 1230.70
399.40 12.50 .522 .1855 .00 12.50 1275.52
399.50 12.65 .541 .1874 .00 12.65 1320.79
399.60 12.80 .559 .1893 .00 12.8,0 1366.52
399.70 12.95 .578 .1912 .00 12.95 1412.71
399.80 13.09 .598 .1931 .00 13.09 1459.34
399.90 13.24 .617 .1951 .00 13.24 1506.46
II 400.00 13.38 .637 .1970 .00 13.38 1554.05
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... C and Area Page 7.01
Name.... AREA POND C
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
RATIONAL C COEFFICIENT DATA
-------------------------------------------------------------------------
Area C x Area
Soil/Surface Description C acres acres
-------------------------------- -------- ---------- ----------
Impervious Area 1.0000 2.730 2.730
Pervious Area .2200 4.790 1.054
WEIGHTED C & TOTAL AREA ---> .5032 7.520 3.784
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Rational Peak Q's Page 7.02
Name.... POST DEV
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND C -TRACT 1 PH 3-4 WETLAND.PPW
SUMMARY OF RATIONAL METHOD PEAK DISCHARGES
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
Rational Storms: RAL IDF.IDQ Raleigh IDF
Tag
----- Freq
--- File IDF Curve

100-yr ---
100 ------------
RAL_IDF.IDF -----------
100-yr IDF -----
Table
Tc = .0833 hrs

Tag
Freq
C
C adj ----------
j C --------
I -----------
Area
Peak Q

----- (years)
------
----- factor
--- final in/hr acres cfs

2-yr
2
.503 ---
1.000 ----------
.503 --------
5.7600 -----------?
7.520 ----------
21.98
10-yr 10 .503 1.000 .503 7.5000 7.520 28.62
100-yr 100 .503 1.000 .503
---------- 9.7200
-------- 7.520
----------- 37.09
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Mod. Rational Storm Calcs Page 7.03
Name.... AREA POND C Tag: 2-yr Event: 2 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
Storm... 2-yr IDF Table Tag: 2-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 2 yr 'C' Adjustment = 1.000Allowable Q = 7.00 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .6000 hrs Tc = .0833 hrs
Hydrograph File: 2-yr
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'Cl --'C' -- hrs in/hr acres =
cfs
i ac_ft ac-ft

.503 .503 --
---
.0833 --
-
5.7600
7.520 -
--
- -
21.98 ----
-
.151 -
-
.103
.503 .503 .1667 4.7640 7.520 18.18 .250 .178
.503 .503 .2500 4.0400 7.520 15.42 .318 .222
.503 .503 .3333 3.4685 7.520 13.23 .365 .244
.503 .503 .5000 2.7000 7.520 10.30 I .426 .257
************************************************************ Storage Maximum
.503 .503 .6000 2.4485 7.520 9.34 .463 .266
****************************************************************************
503 .503 .6667 2.2808 7.520 8.70 I .479 .263
503 .503 .8333 1.9395 7.520 7.40 .510 .245
503 .503 1.0000 1.7000 7.520 6.49
Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Mod. Rational Storm Calcs Page 7.04
Name.... AREA POND C Tag: 10-yr Event: 10 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
?I Storm... 10-yr IDF Table Tag: 10-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN
------- FREQUENCY:
---------- 10 yr 'C' Adjustment = 1.000Allowable
---------------------------------------- Q = 11.00
----------- cfs
--------
Hydrograph Storm Duration, Td = .5833 hrs Tc = .0833 hrs
Hydrograph File: 10-yr
VOLUMES
Wtd.
- Adjusted Duration Intens. Area Qpeak Inflow Storage
C'
I ------- 'C'
--------- hrs in/hr acres cfs ac-ft ac-ft

.503 -
.503 ---------
.0833 -----------
7.5000 --------
7.520 --------- --
28.62 -----------
.197 --------
.121
.503 .503 .1667 6.1355 7.520 23.41 ( .322 .209
.503 .503 .2500 5.2500 7.520 20.03 I .414 .262
.503 .503 .3333 4.6218 7.520 17.63 I .486 .296
.503 .503 .5000 3.7100 7.520 14.16 I .585 .320
***************** ******************************************* Storage Maximum
503 .503 .5833 3.4306 7.520 13.09 I .631 .328

.503 .503 .6667 3.1511 7.520 12.02 .662 .322
.503 .503 .8333 2.7094 7.520 10.34 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Type.... Mod. Rational Storm Calcs Page 7.05
Name.... AREA POND C Tag: 100-yr Event: 100 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND C_TRACT 1 PH 3-4_WETLAND.PPW
Storm... 100-yr IDF Table Tag: 100-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 100 yr 'C' Adjustment = 1.000Allowable Q = 12.00 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .7333 hrs Tc = .0833 hrs
Hydrog raph File: 100-yr
VOLUMES
Wtd.
' Adjusted Duration Intens. Area Qpeak Inflow Storage
C'
------ 'C'
----------- hrs
--------- in/hr
----------- acres cfs ac-ft ac-ft

.503
.503
.0833
9.7200 --------
7.520 --------- ---
37.09 I ----------
.255 --------
.172
.503 .503 .1667 8.4053 7.520 32.07 I .442 .318
.503 .503 .2500 7.2400 7.520 27.62 I .571 .405
.503 .503 .3333 6.4676 7.520 24.68 I 680 .473
.503 .503 .5000 5.2800 7.520 20.15 I .832 .543
.503 .503 .6667 4.4816 7.520 17.10 I .942 .570
****** ****************************************************** Storage Maximum
.503 .503 .7333 4.2402 7.520 16.18„l .981 .576
****** ************************************************************** ********
.503 .503 .8333 3.8792 7.520 14.80 1.019 .565
.503 .503 1.0000 3.5000 7.520 13.35 I 1.104 .567
.503 .503 2.0000 2.0000 7.520 7.63 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Elev. vs. Flow
STAGE-DISCHARGE FUNCTION FOR OUTLET
d
w
Hydrograph for 2-year Design Storm
POND C IN v5 OUT
U
3
0
LL
Plotted Curves
OUTLET POND C
Plotted Curves
WETLAND IN 2-yr
WETLAND OUT 2-yr
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Flow (cfs)
0'.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Hydrograph for 10-year Design Storm
POND C IN vs OUT
w
0
M
w
U
3
LL
I
13
!
. !
t
I
12 _.. ?. (..... .

10
?
I ..
..

s
!
-
.
- -f--
i
..
. _ ; '. .

... ...

.. -_
?.
- - -

8 --

{
I
s _ I ...
. ..
. .

..-..
_.... 1_.
I ... _
.. .._... ...t i ...... i
! V
- r
l
_ _ _
_; 1 . ..
f_ ... _

3 ! . ..

2
-
i {
1 -- . _
E

I
_... E f k I
0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
Hydrograph for 100-year Design Storm
POND C IN vs OUT
Plotted Curves
WETLAND IN 10-yr
WETLAND OUT 10-yr
Plotted Curves
WETLAND IN 100-yr
WETLAND OUT 100-yr
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
LONG LAKE SUBDIVISION - TRACT 1, PHASES 3 & 4
POND C - PONDPACK OUTPUT
Volume vs. Time
MINIMUM DRAIN TIME - Runoff from first 1" Rainfall

U
l0
N
E
0
Plotted Curves
MDRAIN OUT
0 10 20 30 40 50 60 70
Time (hrs)
I
t
? POND D
Long Lake Subdivision
Tract 1, Phase 2
r
I?

Project Name: Long Lake Subdivision
City/State: Raleigh, NC
POND D - TRACT 1, PHASE 2 (Dry Pond)
Proiect M. 201113.2
Date: 14-Aug-02
Rational
C Fraction
IA Total
Area (ac) Pervious
(ac) Impervious
(ac)
Pervious Area 0.22 0 5.64 5.64 0
Impervious 0.95 1.00 5.31 0 5.31
Totals 10.95 5.64 5.31
% Impervious Surface Area = 48 %
1-Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
1 Rv = 0.05 + 0.009(1) where, Rv = Runoff coefficient, in./in.
I = Percent impervious
Rv = 0.49 in./in.
Total runoff volume from 1-inch precipitation:
Runoff volume, S = (Design rainfall) (Rv) (Drainage Area)
S = 0.444 acre-ft
19335 cu. ft.
Elevation for Min. Required Storage= 384.35 feet
Runoff storage provided = 0.443 " ac-ft
Riser structure crest elevation = 384.4 feet
Runoff storage provided = 0:452; ac-ft
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Job File: K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2-DRY POND.PPW
j Rain Dir: I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\
JOB TITLE
--------------------------
--------------------------
LONG LAKE SUBDIVISION - TRACT 1
Pond D - Tract 1, Phase 2
Dry Pond Design
Raleigh, North Carolina
W&R Project #201113
The Modified Rational Method was used to determine peak discharge rates for the 2-year,
10-year and 100-year design storm events for the Raleigh/Durham, North Carolina area and
size the detention storage for the dry detention pond due to the small drainage area
(±10.95 acres). The Modified Rational Method is an extension of the rational method for
rainfalls with durations greater than the time of concentration. The method was modified
so that the concepts of the rational method (peak discharge) could be used to develop
hydrographs for storage routing. The Modified Rational Method within PondPack calculates
the storage volume for hydrographs of rainfalls of various durations to determine the
critical duration for the design storm as the one requiring the greatest detention
storage volume. This critical duration is used to calculate the discharge rate and
volume of water that is routed through the pond structure. The hydrograph developed
maintains the calculated volume and adjusts the peak discharge rate accordingly. Thus,
the peak discharge for the Modified Rational Method is less than the calculated Rational
Method.
The rainfall data used in this design was taken from the Intensity-Duration-Frequency
Table for the Raleigh area published in the City of Raleigh Stormwater Management Design
Manual. The post-development time of concentration was set at 5 minutes to account for
the piped drainage system.
Pond D is an extended dry detention basin that is designed to capture the volume of
runoff from the first'l-inch of rainfall and slowly release it over a 48 to 72 hour
period. The slow release of the runoff from the first 1-inch of rainfall also meets the
requirements for diffuse flow through the riparian buffer. In addition, the dry basin is
designedd to pass the 100-year design storm through the riser/barrel outlet structure of
the pond.
Pond D Design Summary:
Required Storage Volume = 0.444 ac-ft (19,335 cu ft)
Storage Volume Provided = 0.452 ac-ft (19,690 cu ft)
Top of Dam = 386.5'
Calculated Freeboard for the 10-yr design storm = 1.45 ft
Calculated Freeboard for the 100-yr design storm = 1.27 ft
Outlet Structure:
• 48" RCP Riser structure with crest at 384.4'
¦ 24" RCP Barrel; 60 ft length; Inverts at 381' and 379.39'
¦ Floating Skimmer device with constant Q = 0.09 cfs for draw-down
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
II
Table of Contents
********************** MASTER SUMMARY **********************
Watershed....... Mod. Rational Grand Summary ........ 1.01
Master Network Summary ............. 1.02
********************** RAINFALL DATA ***********************
2-yr IDF Table.. 2-yr
I-D-F Table ........................ 2.01
10-yr IDF Table 10-yr
I-D-F Table ........................ 2.01
100-yr IDF Table 100-yr
I-D-F Table ........................ 2.02
*t******************** TC CALCULATIONS *********************
AREA POND D..... Tc Calcs ........................... 3.01
*********************** POND VOLUMES ******r****************
DRY POND........ Vol: Elev-Area ..................... 4.01
******************** OUTLET STRUCTURES *********************
OUTLET 1........ Outlet Input Data .................. 5.01
Composite Rating Curve ............. 5.04
*********************** POND ROUTING ***********************
DRY POND........ Pond E-V-Q Table ................... 6.01
****************** RATIONAL METHOD CALCS *******************
AREA POND D..... C and Area ......................... 7.01
AREA POND D..... Rational Peak Qs ................... 7.02
AREA POND D..... 2-yr Mod. Rational Storm Calcs ..... 7.03
AREA POND D..... 10-yr Mod. Rational Storm Calcs .... 7.04
AREA POND D..... 100-yr Mod. Rational Storm Calcs ... 7.05
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Mod. Rational Grand Summary Page 1.01
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
************************************************************************
************************************************************************
* *
i * MODIFIED RATIONAL METHOD
* ---- Grand Summary For All Storm Frequencies ----
* *
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)

................ Area =
......... 10.950 acres
............
...... Tc
.............. = .0833
........ hrs
...........
................ ......... ............ ...... .............. ...................
VOLUMES
Freq. Adjusted Duration I Qpeak Allowable Inflow Storage
years 'C' hrs in/hr cfs cfs ac-ft ac-ft
----------------
2 .590 ---------
.5833 ------------
2.4904 ------
16.21 ----------- --
13.00 --------
.781 -----------
.423
10 .590 .6000 3.3747 21.97 18.00 1.089 .581
100 .590 .7333 4.2402 27.60 21.00 1.673 .964
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
MASTER DESIGN STORM SUMMARY
- Default Network Design Storm File, ID RAL_IDF.IDQ Raleigh IDF
Rainfall
Return Event Type IDF File IDF ID
------------
2-yr --------------
I-D-F Table - ----
RAL ----
IDF ----------------
2-yr IDF Table
10-yr I-D-F Table RAL IDF 10-yr IDF Table
100-yr I-D-F Table RAL_ IDF 100-yr IDF Table
MASTER NETWORK SUMMARY
Modified Rational Method Network
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun hrs cfs ft ac-ft
-------------
AREA POND D ---- ----
AREA ------
2 ---------- --
.782 ---------
.0833 --------
16.21 -------- ------------
AREA POND D AREA 10 1.089 .0833 21.97
AREA POND D AREA 100 1.673 .0833 27.60
DRY POND IN POND 2 .781 .0900 16.21
DRY POND IN POND 10 1.088 .0900 21.97
DRY POND IN POND 100 1.673 .0900 27.60
DRY POND OUT POND 2 .474 .5800 15.63 384.94 .543
DRY POND - OUT POND 10 .780 .5900 21.96 385.05 .562
DRY POND OUT POND 100 1.363 .7300 27.03 385.23 .598
*OUT (LAKE) JCT 2 .474 .5800 15.63
*OUT (LAKE) JCT 10 .780 .5900 21.96
*OUT (LAKE) JCT 100 1.363 .7300 27.03
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... I-D-F Table Page 2.01
Name.... 2-yr IDF Table Tag: 2-yr Event: 2 yr
l File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
?I Title... 2-yr Storm from City of Raleigh IDF Table
Storm... 2-yr IDF Table Tag: 2-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833 5.7600
.1670 4.7600
.2500 4.0400
.3330 3.4700
.5000 2.7000
.6670 2.2800
.8330 1.9400
u 1.0000 1.7000
1.5000 1.2200
2.0000 .9500
3.0000 .7100
6.0000 .4400
12.0000 .2600
24.0000 .1500
Type.... I-D-F Table
Name.... 10-yr IDF Table Tag: 10-yr Event: 10 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
Title... 10-yr Event Table from City of Raleigh IDF Table
Storm... 10-yr IDF Table Tag: 10-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3300
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
7.5000
6.1300
5.2500
4.6400
3.7100
3.1500
2.7100
2.4100
1.7400
1.3700
1.0200
.6500
.3900
.2200
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... I-D-F Table Page 2.02
Name.... 100-yr IDF Table Tag: 100-yr Event: 100 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
Title... 100-yr Event from City of Raleigh IDF Table
Storm... 100-yr IDF Table Tag: 100-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3330
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
9.7200
8.4000
7.2400
6.4700
5.2800
4.4800
3.8800
3.5000
2.5300
2.0000
1.5000
.9600
.5700
.3300
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
j POND D - PONDPACK OUTPUT
Type.... Tc Calcs Page 3.01
Name.... AREA POND D
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2 -DRY POND.PPW
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: User Defined
Description: Tc = 5 minutes
Segment #1 Time: .0833 hrs
------------------------------------------------------------------------
-------------------------
-------------------------
Total Tc: .0833 hrs
Calculated Tc < Min.Tc:
Use Minimum Tc...
Use Tc = .0833 hrs
-------------------------
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Vol: Elev-Area
Name.... DRY POND
Page 4.01
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
Elevation Planimeter Area Al+A2+sgr(Al*A2) Volume Volume Sum
(ft) (sq.in) (acres) (acres)
--- (ac-ft)
--
------- (ac-ft)
-----
-
-
------------
381.00 ---------------------
----- .0903 -------------
.0000 -
.000 ----
--
.000
382.00 ----- .1170 .3101 .103 .103
384.00 ----- .1614 .4158 .277 .381
385.50 ----- .1979 .5380 .269 .650
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Area2))
where: ELI, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for ELI, EL2, respectively
Volume = Incremental volume between ELI and EL2
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Outlet Input Data Page 5.01
Name.... OUTLET 1
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2 DRY POND.PPW
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 381.00 ft
Increment = .10 ft
Max. Elev.= 3'85.50 ft
**********************************************
OUTLET CONNECTIVITY
**********************************************
---> Forward Flow Only (Upstream to DnStream)
<--- Reverse Flow Only (DnStream to UpStream)
< --- > Forward and Reverse Both Allowed
Structure No. Outfall E1, ft E2, ft
User Defined Table SK ---> TW .000 385.500
Stand Pipe RI ---> CV 384.400 385.500
Culvert-Circular CV ---> TW 381.000 385.500
TW SETUP, DS Channel
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Outlet Input Data
Name.... OUTLET 1
Page 5.02
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = SK
Structure Type = User Defined Table
------------------------------------
ELEV-FLOW RATING TABLE
Elev, ft Flow, cfs
--------- ---------
381.00 .09
385.50 .09
Structure ID = RI
Structure Type = Stand Pipe
-----------------
# of Openings -------------
= 1 ------
Invert Elev. = 384.40 ft
Diameter = 4.0000 ft
Orifice Area = 12.5664 sq.ft
Orifice Coeff. _ .600
Weir Length = 12.57 ft
Weir Coeff. = 3.100
K, Submerged = .000
K, Reverse = 1.000
Kb,Barrel = .000000 (per ft of full flow)
Barrel Length = .00 ft
Mannings n = .0000
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Outlet Input Data
Name.... OUTLET 1
Page 5.03
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2-DRY POND.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = CV
Structure Type = Culvert-Circular
------------------
No. Barrels ------------
= i ------
Barrel Diameter = 2.0000 ft
Upstream Invert = 381.00 ft
Dnstream Invert = 379.39 ft
Horiz. Length = 50.00 ft
Barrel Length = 50.03 ft
Barrel Slope = .03220 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .5000
Kb = .012411
Kr = .5000
HW Convergence = .001
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0098
Inlet Control M = 2.0000
1 Inlet Control c = .03980
Inlet Control Y = .6700
T1 ratio (HW/D) = 1.144
T2 ratio (HW/D) = 1.291
Slope Factor = -.500
(forward entrance loss)
(per ft of full flow)
(reverse entrance loss)
+/- ft
Use unsubmerged inlet control Form 1 equ. below Ti elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev- 383.29 ft ---> Flow = 15.55 cfs
At T2 Elev = 383.58 ft ---> Flow = 17.77 cfs
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFALL CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES ...
Maximum Iterations= 30
Min. TW tolerance = .01 ft
Max. TW tolerance = .01 ft
Min. HW tolerance = .01 ft
Max. HW tolerance = .01 ft
Min. Q tolerance = .10 cfs
Max. Q tolerance = .10 cfs
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Composite Rating Curve
Name.... OUTLET 1
Page 5.04
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q Notes
-------- -------- ------ -- Converge --- ----- -- ---------------
Elev. Q TW Elev Error
ft
-------- cfs
------- ft
- +/-ft Contributing Structures

381.00
.09 -----
Free -- ----- -
Outfall ---
SK -----
(no --
Q: ---------------
RI,CV)
381.10 .09 Free Outfall SK (no Q: RI,CV)
381.20 .09 Free Outfall SK (no Q: RI,CV)
381.30 .09 Free Outfall SK (no Q: RI,CV)
381.40 .09 Free Outfall SK (no Q: RI,CV)
381.50 .09 Free Outfall SK (no Q: RI,CV)
381.60 .09 Free Outfall SK (no Q: RI,CV)
381.70 .09 Free Outfall SK (no Q: RI,CV)
381.80 .09 Free Outfall SK (no Q: RI,CV)
381.90 .09 Free Outfall SK (no Q: RI,CV)
382.00 .09 Free Outfall SK (no Q: RI,CV)
382.10 .09 Free Outfall SK (no Q: RI,CV)
382.20 .09 Free Outfall SK (no Q: RI,CV)
382.30 .09 Free Outfall SK (no Q: RI,CV)
382.40 .09 Free Outfall SK (no Q: RI,CV)
382.50 .09 Free Outfall SK (no Q: RI,CV)
382.60 .09 Free Outfall SK (no Q: RI,CV),,
- 382.70 .09 Free Outfall SK (no Q: RI,CV)
382.80 .09 Free Outfall SK (no Q: RI,CV)
382.90 .09 Free Outfall SK (no Q: RI,CV)
383.00 .09 Free Outfall SK (no Q: RI,CV)
383.10 .09 Free Outfall SK (no Q: RI,CV)
383.20 .09 Free Outfall SK (no Q: RI,CV)
383.30 .09 Free Outfall SK (no Q: RI,CV)
383.40 .09 Free Outfall SK (no Q: RI,CV)
383.50 .09 Free Outfall SK (no Q: RI,CV)
383.60 .09 Free Outfall SK (no Q: RI,CV)
383.70 .09 Free Outfall SK (no Q: RI,CV)
383.80 .09 Free Outfall SK (no Q: RI,CV)
383.90 .09 Free Outfall SK (no Q: RI,CV)
384.00 .09 Free Outfall SK (no Q: RI,CV)
384.10 .09 Free Outfall SK (no Q: RI,CV)
384.20 .09 Free Outfall SK (no Q: RI,CV)
384.30 .09 Free Outfall SK (no Q: RI,CV)
384.40 .09 Free Outfall SK (no Q: RI,CV)
384.50 1.32 Free Outfall SK, RI,CV
384.60 3.57 Free Outfall SK, RI,CV
384.70 6.49 Free Outfall SK, RI,CV
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Composite Rating Curve
Name.... OUTLET 1
Page 5.05
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q Notes
-------- -------- ----- --- Converge -------
------------------
Elev. Q TW Elev Error
ft
-------- cfs
---- ft +/-ft Contributing Structures

384.80 ---
9.94 -----
Free --- -----
Outfall --------------------------
SK,RI,CV
384.90 13.86 Free Outfall SK,RI,CV
385.00 18.20 Free Outfall SK,RI,CV
385.10 26.40 Free Outfall SK,RI,CV
385.20 26.87 Free Outfall SK,RI,CV
385.30 27.33 Free Outfall SK,RI,CV
385.40 27.78 Free Outfall SK,RI,CV
385.50 28.22 Free Outfall SK,RI,CV
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Pond E-V-Q Table Page 6.01
Name.... DRY POND
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2 -DRY POND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\
Inflow HYG file = NONE STORED - DRY POND IN 2-yr
Outflow HYG file = NONE STORED - DRY POND OUT 2-yr
Pond Node Data = DRY POND
Pond Volume Data = DRY POND
Pond Outlet Data = OUTLET 1
No Infiltration
INITIAL CONDITIONS
---------
Starting -----------
WS Elev = ---------
381.00 ----
ft -
Starting Volume = .000 ac- ft
Starting Outflow = .09 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .09 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + O
ft
---
--------- cfs
---- ac-ft acres cfs cfs cfs
-
381.00 -------
.09 ---------
.000 ---- --------
.0903 -----------
.00 ------------
.09 ----------
.09
381.10 .09 .009 .0928 .00 .09 22.25
381.20 .09 .019 .0954 .00 .09 45.02
381.30 .09 .028 .0979 .00 .09 68.40
381.40 .09 .038 .1006 .00 .09 92.42
381.50 .09 .048 .1032 .00 .09 117.08
381.60 .09 .059 .1059 .00 .09 142.39
381.70 .09 .070 .1086 .00 .09 168.35
381.80 .09 .081 .1114 .00 .09 194.96
381.90 .09 .092 .1142 .00 .09 222.25
382.00 .09 .103 .1170 .00 .09 250.23
382.10 .09 .115 .1191 .00 .09 278.79
382.20 .09 .127 .1211 .00 .09 307.85
382.30 .09 .139 .1232 .00 .09 337.41
382.40 .09 .152 .1253 .00 .09 367.48
382.50 .09 .164 .1274 .00 .09 398.06
382.60 .09 .177 .1296 .00 .09 429.16
382.70 .09 .190 .1317 .00 .09 460.78
382.80 .09 .204 .1339 .00 .09 492.91
382.90 .09 .217 .1361 .00 .09 525.59
383.00 .09 .231 .1383 .00 .09 558.79
f 383.10 .09 .245 .1405 .00 .09 592.53
383.20 .09 .259 .1428 .00 .09 626.82
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Pond E-V-Q Table Page 6.02
Name.... DRY POND
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\
Inflow HYG file = NONE STORED - DRY POND IN 2-yr
Outflow HYG file = NONE STORED - DRY POND OUT 2-yr
Pond Node Data = DRY POND
Pond Volume Data = DRY POND
Pond Outlet Data = OUTLET 1
No Infiltration
INITIAL CONDITIONS
--------
Starting -------------
WS Elev = ---------
381.00 ---
ft -
Starting Volume = .000 ac- ft
Starting Outflow = .09 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .09 cfs
Time Inc rement = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + 0
ft cfs ac-ft acres cfs cfs cfs
------------
383.30 ------------
.09 ---------
.273 ---- --------
.1450 -----------
.00 ------------
.09 ----------
661.64
383.40 .09 .288 .1473 .00 .09 697.02
383.50 .09 .303 .1496 .00 .09 732.95
383.60 .09 .318 .1520 .00 .09 769.44
383.70 .09 .333 .1543 .00 .09 806.50
383.80 .09 .349 .1566 .00 .09 844.11
383.90 .09 .365 .1590 .00 .09 882.31
384.00 .09 .381 .1614 .00 .09 921.08
384.10 .09 .397 .1637 .00 .09 960.42
384.20 .09 .413 .1661 .00 .09 1000.33
384.30 .09 .430 .1684 .00 .09 1040.78
384.40 .09 .447 .1708 .00 .09 1081.83
384.50 1.32 .464 .1732 .00 1.32 1124.68
384.60 3.57 .482 .1756 .00 3.57 1169.12
384.70 6.49 .499 .1780 .00 6.49 1214.82
384.80 9.94 .517 .1804 .00 9.94 1261.63
384.90 13.86 .535 .1829 .00 13.86 1309.50
385.00 18.20 .554 .1853 .00 18.20 1358.38
385.10 26.40 .572 .1878 .00 26.40 1411.74
385.20 26.87 .591 .1903 .00 26.87 1457.96
385.30 27.33 .611 .1928 .00 27.33 1504.77
385.40 27.78 .630 .1954 .00 27.78 1552.19
385.50 28.22 .650 .1979 .00 28.22 1600.22
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... C and Area
Name.... AREA POND D
Page 7.01
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2-DRY POND.PPW
Title... Revised Drainage Area - 6/10/02
RATIONAL C COEFFICIENT DATA
.........................................................................
.........................................................................
Revised Drainage Area - 6/10/02
-------------------------------------------------------------------------
Area C x Area
Soil/Surface Description
- C acres acres
-------------------------------
Impervious Area --------
.9500 ----------
5.310 ----------
5.045
Pervious Area .2500 5.640 1.410
WEIGHTED C & TOTAL AREA --->
.................................
................................. .5895
............
............ 10.950
.............
............. 6.455
...............
...............
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Rational Peak Q's
Name.... POST DEV POND D
Page 7.02
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\POND D -TRACT 1 PH 2 -DRY POND.PPW
SUMMARY OF RATIONAL METHOD PEAK DISCHARGES
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
Rational Storms: RAL IDF.IDQ Raleigh IDF
Tag Freq File IDF Curve
-----
100-yr ------
100 ------
RAL_ID ------
F.IDF -----------
100-yr IDF -----
Table
Tc = .0833 hrs

Tag
Freq
C
C adj ----------
C --------
I -----------
Area
Peak Q

----- (years)
------
--- factor final in/hr acres cfs

2-yr
2 --
.590 ------
1.000 ----------
.590 --------
5.7600 -----------)
10.950 ----------
37.49
10-yr 10 .590 1.000 .590 7.5000 10.950 48.82
100-yr 100 .590 1.000 .590
---------- 9.7200
-------- 10.950
----------- 63.27
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Mod. Rational Storm Calcs Page 7.03
Name.... AREA POND D Tag: 2-yr Event: 2 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2-DRY POND.PPW
Storm... 2-yr IDF Table Tag: 2-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN
------ FREQUENCY:
----------- 2 yr 'C'
---------- Adjustment
----------- = 1.000Allowable
------------------- Q = 13.00
--------- cfs
----------
Hydrograph Storm Duration, Td = .5833 hrs Tc = .0833 hrs
Hydrograph File: 2-yr
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'C'
------ 'C'
----------- hrs
-------- in/hr acres cfs ac-ft ac-ft

.590
.590 --
.0833 -----------
5.7600 -------
10.950 --------- --
37.49 ---------
.258 ----------
.169
.590 .590 .1667 4.7640 10.950 31.01 I .427 .293
.590 .590 .2500 4.0400 10.950 26.30 I .543 .364
.590 .590 .3333 3.4685 10.950 22.58 .622 .398
.590 .590 .50010 2.7000 10.950 17.57 .726 .413
************************************************************ Storage Maximum
.590 .590 .5833 2.4904 10.950 16.21 .781 .423
****************************************************************************
.590 .590 .6667 2.2808 10.950 14.85 .818 .415
.590 .590 .8333 1.9395 10.950 12.62 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Mod. Rational Storm Calcs Page 7.04
Name.... AREA POND D Tag: 10-yr Event: 10 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2-DRY POND.PPW
Storm... 10-yr IDF Table Tag: 10-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN
------- FREQUENCY:
---------- 10 yr 'C' Adjustment = 1.000Allowable
----------------------------------------- Q = 18.00
--------- cfs
---------
Hydrograph Storm Duration, Td = .6000 hrs Tc = .0833 hrs
Hydrograph File: 10-yr
...... ........... ......... ........... ......... ........... ...................
VOLUMES
= Wtd. Adjusted Duration Intens. Area Qpeak ( Inflow Storage
'C'
------- 'C'
----
- hrs in/hr acres
- cfs ac-ft ac-ft

.590 -
----
.590 ---------

.0833 ------
-----
7.5000
-------
10.950
--------- --
48.82
----------
.336
---------
.212
.590 .590 .1667 6.1355 10.950 39.93 I .550 .364
.590 .590 .2500 5.2500 10.950 34.17 I .706 .458
.590 .590 .3333 4.6218 10.950 30.08 .829 .519
.590 .590 .5000 3.7100 10.950 24.3.5 .998 .564
************************************************************ Storage Maximum
.590 .590 .6000 3.3747 10.950 21.97 1.089 .581
.590 .590 .6667 3.1511 10.950 20.51 1.130 .572
.590 .590 .8333 2.7094 10.950 17.64 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Type.... Mod. Rational Storm Calcs Page 7.05
Name.... AREA POND D Tag: 100-yr Event: 100 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\POND D_TRACT 1 PH 2-DRY POND.PPW
Storm... 100-yr IDF Table Tag: 100-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 100 yr 'C' Adjustment = 1.000Allowable Q = 21.00 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .7333 hrs Tc = .0833 hrs
Hydrograph File:
................ 100-yr
..........
...........
........
............
..........
.........
................ .......... ........... ........ ............ ..........
VOLU .........
MES
Wtd. Adjusted Duration Intens. Area Qpeak I Inflow Storage
'C' 'C'
--- hrs in/hr acres
-
- cfs
--------- -- ac-ft
---------- ac-ft
---------
----
---------
.590 .590 ----------
.0833 -----------
9.7200 --
----
10.950 63.27 I .436 .291
.590 .590 .1667 8.4053 10.950 54.71 I .754 .537
.590 .590 .2500 7.2400 10.950 47.12 .974 .684
.590 .590 .3333 6.4676 10.950 42.10 1.160 .798
.590 .590 .5000 5.2800 10.950 34.37 I 1.420 .914
.590 .590 .6667 4.4816 10.950 29.17 1.607 .956
***********************************************************,* Storage Maximum
.590 .590 .7333 4.2402 10.950 27.60 1.673 .964
****************************************************************************
.590 .590 .8333 3.8792 10.950 25.25 1.739 .944
.590 .590 1.0000 3.5000 10.950 22.78 1.883 .943
.590 .590 2.0000 2.0000 10.950 13.02 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
Plotted Curves
OUTLET 1
N
3
0
Hydrograph for 2-yr Design Storm
DRY POND IN vs OUT
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
Plotted Curves
DRY POND IN 2-yr
DRY POND OUT 2-yr
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Hydrograph for 10-year Design Storm
DRY POND IN vs OUT
w
U
3
0
LL
w
U
3
0
LL
Plotted Curves
DRY POND IN 10-yr
DRY POND OUT 10-yr
Plotted Curves
DRY POND IN 100-yr
DRY POND OUT 100-yr
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
Hydrograph for 100-year Design Storm
DRY POND IN ?s OUT
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
LONG LAKE SUBDIVISION - TRACT 1, PHASE 2
POND D - PONDPACK OUTPUT
Volume vs. Time
MINIMUM DRAIN TIME - Runoff from first 1" Rainfall
U
(0
a?
E
0
Plotted Curves
MDRAIN OUT
0 10 20 30 40 50 60 70
Time (hrs)
Project Name: Long Lake Subdivision - Tract 2, Phase 2 Project #: 201113.1
Ci /State: Raleigh, NC Date: 23 Jul-02
1 Table 1.1 Surface Area to Drainage Area Ratio for Permanent Pool Sizing for 85% Pollutant
7f Removal Efficiency in the Piedmont
% Impervious
Cover Permanent Pool Dept
3.0 4.0 5.0 6.0 h (feet)
7.0 8.0 9.0
10 0.59 0.49 0.43 0.35 731 0.29 0.26
20 0.97 0.79 0.70 0.59 0.51 0.46 0.44
30 1.34 1.08 0.97 0.83 0.70 0.64 0.62
40 1.73 1.43 1.25 1.05 0.90 0.82 0.77
50 2.06 1.73 1.50 1.30 1.09 1.00 0.92
60 2.40 2.03 1.71 1.51 1.29 1.18 1.10
70 2.88 2.40 2.07 1.79 1.54 1.35 1.26
80 3.36 2.78 2.38 2.10 1.86 1.60 1.42
90 3.74 3.10 2.66 2.34 2.11 1.83 1.67
Source: NCDENR/DWQ Stormwater Best Management Practices, pg. 5, April 1999
POND E (Constructed Wetland in Tract 2 - FES #42)
Impervious
(sq ft) (ac) Pervious
(sq ft) (ac) Total
(ac)
Pervious Area 0 0 135743 3.12 3.12
Streets 67117 1.54 0 0.00 1.54
Sidewalks 10735 0.25 0 0.00 0.25
Lots (impervious %) 75600 1.74 0 0.00 1.74
Totals 153452 3.52 135743 3.12 6.64
% Impervious Surface Area = 53 %
III Surface Area of Permanent Pool:
Assumed depth = 3 feet
SA/DA ratio - 2.16 % From Table 1.1
Minimum pond surface area (SA) _ (DA * SA/DA ratio)/100
SA = 0.144 acres
6252 sq. ft.
I Normal pool elevation 384.25 feet
?
Surface area provided o 144'- acres
6291 sq. ft.
1-Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (1987)
Rv = 0.05 + 0.009(1) where, Rv = Runoff coefficient, in./in.
I - Percent impervious
Rv = 0.528 in./in.
Total runoff volume from 1-inch precipitation:
Runoff volume, S - (Design rainfall) (Rv) (Drainage Area)
S = 0.292 acre-ft
12714 cu. ft.
Riser structure crest elevation - 386.5 feet
Runoff storage provided - 013,70 ac-ft
16117 cu. ft.
0\01\01-110\01113\HHISWMP\Pulte Stormwater Calcs_Wetlandsjun02.xls
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
¶ Job File: K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
?I Rain Dir: I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\
___--===JOB TITLE====_____
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - Extended Detention Wetland at FES #42
Raleigh, North Carolina
W&R Project #201113.1
The Modified Rational Method was used to determine peak discharge rates for the 1-year,
2-year, 10-year and 100-year design storm events for the Raleigh/Durham, North Carolina
area and size the detention storage for the dry detention pond due to the small drainage
area (±6.6 acres). The Modified Rational Method is an extension of the rational method
for rainfalls with durations greater than the time of concentration. The method was
modified so that the concepts. of the rational method (peak discharge) could be used to
develop hydrographs for storage routing. The Modified Rational Method within PondPack
calculates the storage volume for hydrographs of rainfalls of various durations to
determine the critical duration for the design storm as the one requiring the greatest
detention storage volume. This critical duration is used to calculate the discharge rate
and volume of water that is routed through the pond structure. The hydrograph developed
maintains the calculated volume and adjusts the peak discharge rate accordingly. Thus,
the peak discharge for the modified Rational Method is less than the calculated Rational
Method.
The rainfall data used in this design was taken from the Intensity-Duration-Frequency
Table for the Raleigh area published in the City of Raleigh Stormwater Management Design
II Manual. The post-development time of concentration was set at 5 minutes to account for
the piped drainage system.
Pond E is an extended detention wetland that is designed to capture the volume of runoff
from the first 1-inch of rainfall and slowly release it over a 48 to 72 hour period. In
addition, the wetland is designed to pass the 100-year design storm through the
41 riser/barrel outlet structure of the pond.
Pond E Design Highlights:
Normal Pool Elevation = 384.25'
Required Surface Area = 0.144 acres (6252 sq. ft.)
Surface Area Provided = 0.144 acres (6292 sq. ft.)
Required Storage Volume = 0.292 ac-ft
l Storage Volume Provided = 0.370 ac-ft at 386.5'
Top of Dam = 388,
Calculated Freeboard for the 10-yr design storm = 1.01 ft
Calculated Freeboard for the 100-yr design storm = 0.86 ft
Outlet Structure:
¦ 48" RCP Riser structure with crest at 386.5'
• 48 linear feet of 24" RCP Barrel with inverts at 377.48' and 377'
¦ 1.75" Circular Orifice at 384.25' for extended draw-down
LONG LAKE SUBDIVISION - TRACT 2, PHASES 2
POND E - PondPack Output for Wetland Design
II
Table of Contents
********************** MASTER SUMMARY **********************
Watershed....... Mod. Rational Grand Summary ........ 1.01
Master Network Summary ............. 1.02
********************** RAINFALL DATA *,t*********************
1-yr IDF Table.. 1-yr
I-D-F Table ........................ 2.01
2-yr IDF Table.. 2-yr
I-D-F Table ........................ 2.01
10-yr IDF Table 10-yr
I-D-F Table ........................ 2.02
100-yr IDF Table 100-yr
I-D-F Table ........................ 2.02
********************** TC CALCULATIONS *********************
TRACT 2 AREA#1.. Tc. Calcs ........................... 3.01
*********************** POND VOLUMES *****,t*****************
WETLAND A....... Vol: Elev=Area ..................... 4.01
******************** OUTLET STRUCTURES *********************
OUTLET A........ Outlet Input Data .................. 5.01
Composite Rating Curve ............. 5.04
*****************,r***** POND ROUTING *************,tt********
WETLAND A....... Pond E-V-Q Table ................... 6.01
****************** RATIONAL METHOD CALCS *******************
TRACT 2 AREA A.. 1-yr
Mod. Rational Storm Calcs .......... 7.01
TRACT 2 AREA A.. 2-yr
Mod. Rational Storm Calcs .......... 7.02
TRACT 2 AREA A.. 10-yr
Mod. Rational Storm Calcs .......... 7.03
TRACT 2 AREA A.. 100-yr
Mod. Rational Storm Calcs .......... 7.04
TRACT 2 AREA#1.. C and Area ......................... 7.05
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Mod. Rational Grand Summary Page 1.01
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
************************************************************************
************************************************************************
* *
* *
* MODIFIED RATIONAL METHOD
* ---- Grand Summary For All Storm Frequencies ----
* *
* *
************************************************************************
************************************************************************
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)

................ Area =
......... 6.650 acres
...........
........ Tc
.............. = .0833
....... hrs
...........
................ ......... ........... ........ .............. ..................
VOLUMES
Freq. Adjusted Duration I Qpeak Allowable) Inflow Storage
years 'C'
---------- hrs
-
----- in/hr
----------- cfs
-------- cfs
---------- -- ac-ft ac-ft
------
1 .608 -
--
.4000
2.5289
10.30 -
8.70 -------
.341 -----------
.167
2 .608 .4000 3.1611 12.88 10.90 I .426 .208
10 .608 .4167 4.1659 16.97 15.00 .584 .274
1,00 .608 .5667 4.9606 20.21 18.00 .946 .463
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
I?
MASTER DESIGN STORM SUMMARY
Default Network Design Storm File, ID RAL_IDF.IDQ Raleigh IDF
Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
Return Event
------------
1-yr
2-yr
10-yr
100-yr
Rainfall
Type
---------------
I-D-F Table
I-D-F Table
I-D-F Table
I-D-F Table
IDF File IDF ID
RAL IDF 1-yr IDF Table
RAL IDF 2-yr IDF Table
RAL IDF 10-yr IDF Table
RAL IDF 100-yr IDF Table
MASTER NETWORK SUMMARY
Modified Rational Method Network
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
Node ID
------ Type Event ac-ft Trun
-----------
*OUTFALL A ----
JCT ------
1 ---------- --
.163
*OUTFALL A JCT 2 .221
*OUTFALL A JCT 10 .379
*OUTFALL A JCT 100 .740
TRACT 2 AREA A AREA 1 .340
TRACT 2 AREA A AREA 2 .425
TRACT 2 AREA A AREA 10 .584
TRACT 2 AREA A AREA 100 .946
WETLAND A IN POND 1 .340
WETLAND A IN POND 2 .425
WETLAND A IN POND 10 .584
WETLAND A IN POND 100 .946
WETLAND A OUT POND 1 .163
WETLAND A OUT POND 2 .221
WETLAND A OUT POND 10 .379
WETLAND A OUT POND 100 .740
Max
Qpeak Qpeak Max WSEL Pond Storage
hrs
--------- cfs
-------- ft ac-ft

.4300
.11 -------- ------------
.4600 3.77
.4300 13.63
.5600 2.0.11
.0833 10.30
.0833 12.88
.0833 16.97
.0833 20.21
.0900 10.30
.0900 12.88
.0900 16.97
.0900 20.21
.4300 .11 386.33 .337
.4600 3.77 386.71 .406
.4300 13.63 386.99 .460
.5600 20.11 387.14 .488
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... I-D-F Table Page 2.01
Name.... 1-yr IDF Table Tag: 1-yr Event: 1 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
Title... 1-yr Design Storm (80% of 2-yr)
Storm... 1-yr IDF Table. Tag: 1-yr
Rainfall-Intensity-Duration Curve
Time, hrs
----------- Intens., in/hr
-----------
.0833 4.6080
.1670 3.8080
.2500 3.2320
.3330 2.7760
.5000 2.1600
.6670 1.8240
.8330 1.5520
1.0000 1.3600
1.5000 .9760
2.0000 .7600
3.0000 .5680
6.0000 .3520
12.0000 .2080
24.0000 .1200
Type.... I-D-F Table
Name.... 2-yr IDF Table Tag: 2-yr Event: 2 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL IDF.IDF
Title... 2-yr Storm from City of Raleigh IDF Table
Storm... 2-yr IDF Table Tag: 2-yr
Rainfall-Intensity-Duration Curve
Time, hrs
----------- Intens., in/hr
-----------
.0833 5.7600
.1670 4.7600
.2500 4.0400
.3330 3.4700
.5000 2.7000
.6670 2.2800
.8330 1.9400
1.0000 1.7000
1.5000 1.2200
2.0000 .9500
3.0000 .7100
6.0000 .4400
12.0000 .2600
24.0000 .1500
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... I-D-F Table Page 2.02
Name.... 10-yr IDF. Table Tag: 10-yr Event: 10 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL_IDF.IDF
Title... 10-yr Event Table from City of Raleigh IDF Table
Storm... 10-yr IDF Table Tag: 10-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833
.1670
.2500
.3300
.5000
.6670
.8330
1.0000
1.5000
2.0000
3.0000
6.0000
12.0000
24.0000
7.5000
6.1300
5.2500
4.6400
3.7100
3.1500
2.7100
2.4100
1.7400
1.3700
1.0200
.6500
.3900
.2200
Type.... I-D-F Table.
Name.... 100-yr IDF Table Tag: 100-yr Event: 100 yr
File.... I:\ENGFILE\HAESTAD\PPW RAINFALL DATA\WAKE CO\RAL IDF.IDF
Title... 100-yr Event from City of Raleigh IDF Table
Storm.... 100-yr IDF Table Tag: 100-yr
Rainfall-Intensity-Duration Curve
Time, hrs Intens., in/hr
.0833 9.7200
.1670 8.4000
.2500 7.2400
.3330 6.4700
.5000 5.2800
.6670 4.4800
.8330 3.8800
1.0000 3.5000
1.5000 2.5300
2.0000 2.0000
3.0000 1.5000
6.0000 .9600
12.0000 .5700
24.0000 .3300
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Tc Calcs Page 3.01
Name.... TRACT 2 AREA#1
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: User Defined
Description: Tc = 5. minutes
Segment #1 Time: .0833 hrs
------------------------------------------------------------------------
Total Tc: .0833 hrs
Calculated Tc < Min.Tc:
Use Minimum Tc...
Use Tc .0833 hrs
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Vol: Elev-Area Page 4.01
Name.... WETLAND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
Elevation Planimeter Area Al+A2+sgr(Al*A2) Volume Volume Sum
(ft)
------------ (sq.in) (acres)
-------------------- (acres)
----------------- (ac-ft)
--------- (ac-ft)
-

384.25 -
----- .1444
.0000
.000 ------------
.000
385.00 ----- .1570 .4520 .113 .113
386.00 ----- .1740 .4963 .165 .278
387.00 ----- .1920 .5488 .183 .461
388.00 ----- .2107 .6038 .201 .663
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-ELl) * (Areal + Areal + sq.rt.(Areal*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas.computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Outlet Input Data Page 5.01
Name.... OUTLET A
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
7
REQUESTED POND WS ELEVATIONS:
Min. Elev. 384.25 ft
Increment .10 ft
Max. Elev.= 388.00 ft
Spot Elevations,.ft.
384.25.
**********************************************
OUTLET CONNECTIVITY
---> Forward Flow Only (UpStream to DnStream)
<--- Reverse Flow Only (DnStream to UpStream)
<---> Forward and Reverse Both Allowed
Structure No. Outfall E1, ft E2, ft
Stand Pipe RI ---> CV 386.500 388.000
Orifice-Circular OR ---> CV 384.250 388.000
Culvert-Circular CV ---> TW 377.480 388.000
TW SETUP, DS Channel
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for. Wetland Design
Type.... Outlet Input Data Page 5.02
Name.... OUTLET A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID = RI
Structure Type = Stand Pipe
-----------------
# of openings -------------
= 1 ------
Invert Elev. = 386.50 ft
Diameter = 4.0000 ft
orifice Area = 12.5664 sq.ft
orifice Coeff. _ .600
Weir Length = 12.57 ft
Weir Coeff. = 3.100
K, Submerged = .000
K, Reverse = 1.000
Kb,Barrel = .000000 (per ft of full flow)
Barrel Length = .00 ft
Mannings n = .0000
Structure ID = OR
Structure Type = Orifice-Ci rcular
-----------------
# of openings -------------
= 1 ------
Invert Elev. = 384.25 ft
Diameter = .1458 ft
orifice Coeff. _ .600
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Outlet Input Data Page 5.03
Name.... OUTLET A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID CV
Structure Type = Culvert-Circular.
-------------------
No. Barrels = ----------
1. -------
Barrel Diameter = 2.0000 ft
Upstream Invert = 377.48 ft
Dnstream Invert = 377.00 ft
Horiz. Length = 48.00 ft
Barrel Length = 48.00 ft
Barrel Slope = .01000 ft/ft
OUTLET CONTROL DATA ...
Mannings. n = .0130
Ke = .5000 (forward entrance loss)
Kb = .012411 (per ft of full flow)
Kr = .5000 (reverse entrance loss)
HW Convergence = .001 +/- ft
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0098
Inlet Control M = 2.0000
Inlet Control c = .03980
Inlet Control Y = .6700
T1 ratio (HW/D) = 1.155
T2 ratio (HW/D) = 1.302
Slope Factor = -.500
Use unsubmerged inlet control Form 1 equ. below Ti elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 379.79 ft ---> Flow = 15.55 cfs
At T2 Elev = 380.08 ft ---> Flow = 17.77 cfs.
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFALL CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES ...
Maximum Iterations= 30
Min. TW tolerance = .01 ft
Max. TW tolerance = .01 ft
Min. HW tolerance = .01 ft
Max. HW tolerance = .01 ft
Min. Q tolerance = .10 cfs
Max. Q tolerance = .10 cfs
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Composite Rating Curve
Name.... OUTLET A .
Page 5.04
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q Notes
-------- -------- ------ -- Converge ----------- -- ------------
Elev. Q TW Elev Error
ft cfs . ft +/-ft Contributing Structures
--------
384.25 -------
.00 -----
Free --- -----
Outfall --------------
(no Q: RI,OR ------------
,CV)
384.30 .00 Free Outfall OR,CV (no Q: RI)
384.40 .02 Free Outfall OR,CV (no Q: RI)
384.50 .03 Free Outfall OR,CV (no Q: RI)
384.60 .04 Free Outfall OR,CV (no Q: RI)
384.70 .05 Free Outfall OR,CV (no Q: RI)
384.80 .06 Free Outfall OR,CV (no Q: RI)
384.90 .06 Free Outfall OR,CV (no Q: RI)
385.00 .07 Free Outfall OR,CV (no Q: RI)
385.10 .07 Free Outfall OR,CV (no Q: RI)
385.20 .08 Free Outfall OR,CV (no Q: RI)
385.30 .08 Free Outfall OR,CV (no Q: RI)
385.40 .08 Free Outfall OR,CV (no Q: RI)
385.50 .09 Free Outfall OR,CV (no Q: RI)
385.60 .09 Free Outfall OR,CV (no Q: RI)
385.70 .09 Free Outfall OR,CV (no Q: RI)
385.80 .10 Free Outfall OR,CV (no Q:. RI)
385.90 .10 Free Outfall OR,CV (no Q: RI)
386.00 .10 Free Outfall OR,CV (no Q: RI)
386.10 .11 Free Outfall OR,CV (no Q: RI)
386.20 .11 Free Outfall OR,CV (no Q: RI)
386.30 .11 Free Outfall OR,CV (no Q: RI)
386.40 .12 Free Outfall OR,CV (no Q: RI)
386.50 .12 Free Outfall OR,CV (no Q: RI)
386.60 1.35 Free Outfall RI,OR,CV
386.70 3.61 Free Outfall RI,OR,CV
386.80 6.53 Free Outfall RI,OR,CV
386.90 9.98 Free Outfall RI,OR,CV
387.00 13.90 Free Outfall RI,OR,CV
387.10 18.24 Free Outfall RI,OR,CV
387.20 22.95 Free Outfall RI,OR,CV
387.30 28.01 Free Outfall RI,OR,CV
387.40 33.40 Free Outfall RI,OR,CV
387.50 39.08 Free Outfall RI,OR,CV
387.60 45.00 Free Outfall RI,CV (no Q: OR)
387.70 46.95 Free Outfall RI,CV (no Q: OR)
387.80 47.22 Free Outfall RI,CV (no Q: OR)
387.90 47.48 Free Outfall RI,CV (no Q: OR)
388.00 47.74 Free Outfall RI,CV (no Q: OR)
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Pond E-V-Q Table Page 6.01
Name.... WETLAND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
LEVEL POOL ROUTING DATA
HYG Dir K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\
Inflow HYG file = NONE STORED - WETLAND A IN 1-yr
Outflow HYG file NONE STORED - WETLAND A OUT 1-yr
Pond Node Data =. WETLAND A
Pond Volume Data = WETLAND A
Pond Outlet Data = OUTLET A
No Infiltration
INITIAL CONDITIONS
Starting WS Elev = 384.25 ft
Starting Volume = .000 ac- ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + 0
ft cfs ac-ft acres cfs cfs cfs
------------
384.25 ------------
.00 ----------
.000 --- --------
.1444 -----------
.00 ------------
.00 ----------
.00
384.30 .00 .007 .1452 .00 .00 17.52
384.40 .02 .022 .1469 .00 .02 52.89
384.50 .03 .037 .1485 .00 .03 88.65
384.60 .04 .052 .1502 .00 .04 124.79
384.70 .05 .067 .1519 .00 .05 161.36
384.80 .06 .082 .1536 .00 .06 198.33
384.90 .06 .097 .1553 .00 .06 235.71
385.00 .07 .113 .1570 .00 .07 273.51
385.10 .07 .129 .1587 .00 .07 311.70
385.20 .08 .145 .1603 .00 .08 350.30
385.30 .08 .161 .1620 .00 .08 389.31
385.40 .08 .177 .1637 .00 .08 428.73
385.50 .09 .194 .1654 .00 .09 468.55
385.60 .09 .210 .1671 .00 .09 508.78
385.70 .09 .227 .1688 .00 .09 549.43
385.80 .10 .244 .1705 .00 .10 590.49
385.90 .10 .261 .1723 .00 .10 631.98
386.00 .10 .278 .1740 .00 .10 673.88
386.10 .11 .296 .1758 .00 .11 716.19
386.20 .11 .314 .1775 .00 .11 758.95
386.30 .11 .331 .1793 .00 .11 802.13
386.40 .12 .349 .1811 .00 .12 845.74
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Pond E-V-Q Table Page 6.02
Name..... WETLAND A
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
LEVEL POOL ROUTING DATA
HYG Dir = K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\
Inflow HYG file = NONE STORED - WETLAND A IN 1-yr
Outflow HYG file = NONE STORED .-.WETLAND A OUT 1-yr
Pond Node Data = WETLAND A
Pond Volume Data = WETLAND A
Pond Outlet Data = OUTLET A
No Infiltration
INITIAL CONDITIONS
---------
Starting ------------
WS Elev = --------
384.25 ----
ft -
it Starting Volume = .000 ac- ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0100 hrs
Elevation Outflow Storage Area Infilt. Q Total 2S/t + O
ft cfs ac-ft acres cfs
- cfs cfs
------------
386.50 ------------
.12 ---------
.368 ---- --------
.1829 --------
--
.00 ------------
.12 ----------
889.79
386.60 1.35 .386 .1847 .00 1.35 935.49
386.70 3.61 .405 .1865 .00 3.61 982.66
386.80 6.53 .423 .1883 .00 6.53 1030.94
386.90 9.98 .442 .1902 .00 9.98 1080.20
387.00 13.90 .461 .1920 .00 13.90 1130.36
387.10 18.24 .481 .1938 .00 18.24 1181.37
387.20 22.95 .500 .1957 .00 22.95 1233.21
387.30 28.01 .520 .1975 .00 28.01 1285.85
387.40 33.40 .540 .1994 .00 33.40 1339.27.
387.50 39.08 .560 .2012 .00 39.08 1393.43
387.60 45.00 .580 .2031 .00 45.00 1448.27
387.70 46.95 .600 .2050 .00 46.95 1499.60
387.80 47.22 .621 .2069 .00 47.22 1549.70
387.90 47.48 .642 .2088 .00 47.48 1600.27
388.00 47.74 .663 .2107 .00 47.74 1651.29
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Mod. Rational Storm Calcs Page 7.01
Name.... TRACT 2 AREA A Tag: 1-yr Event: 1 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
Storm... 1-yr IDF Table Tag: 1-yr
MODIFIED. RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 1 yr 'C' Adjustment 1.000Allowable Q = 8.70 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .4000 hrs Tc = .0833 hrs
Hydrograph File: 1-yr
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'Cl 'C'
----------------- hrs
--
----- in/hr
-------- acres cfs ac-ft ac-ft

.608 .608 --
.0833 ---
4.6080 ---------
6.650 -------- --
18.77 I ----------
.129 ---------
.069
.608 .608 .1667 3.8112 6.650 15.53 .214 .124
.608 .608 .2500 3.2320 6.650 13.17 .272 .152
.608 .608 .3333 2.7748 6.650 11.30 .311 .162
************************************************************ Storage Maximum
.608 .608 .4000 2.5289 6.650 10.30 .341 .167
****************************************************************************
.608 .608 .5000 2.1600 6.650 8.80 .364 .154
.608 .608 .6667 1.8247 6.650 7.43 Qpeak < Qallow
LONG LAKE SUBDIVISION TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Mod. Rational Storm Calcs Page 7.02
Name.... TRACT 2 AREA A Tag: 2-yr Event: 2 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
Storm... 2-yr IDF Table Tag: 2-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
1 Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 2 yr 'C' Adjustment 1.000Allowable Q = 10.90 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .4000 hrs Tc = .0833 hrs
Hydrog
...... raph File:
.......... 2-yr
..........
...........
.........
...........
...........
........
...... .......... .......... ........... ......... ........... ...................
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'C'
-- 'C'
-- hrs
--
------- in/hr
-------
- acres
-
- cfs. ac-ft ac-ft
----
.608 --------
.608 -
.0833 ---
5.7600 -
------
6.650 -------- --
23.46 -----------
.162 --------
.086
.608 .608 .1667 4.7640 6.650 19.41 .267 .155
.608 .608 .2500 4.0400 6.650 16.46 .340 .190
.608 .608 .3333 3.4685 6.650 14.13 .389 .202
****** ****************************************************** Storage Maximum
.608 .608 .4000 3.1611 6.650 12.88 .426 .208
****** ************************************************************** ********
.608 .608 .5000 2.7000 6.650 11.00 .454 .192
.608 .608 .6667 ' 2.2808 6.650 9.29 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Mod. Rational Storm Calcs Page 7.03
Name.... TRACT 2 AREA A Tag: 10-yr Event: 10 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
Storm... 10-yr IDF Table Tag: 10-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 10 yr 'C' Adjustment = 1.000Allowable Q = 15.00 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration,. Td = .4167 hrs Tc = .0833 hrs
Hydrograph File:
................ 10-yr
..........
...........
........
............
..........
.........
................ .......... ........... ........ ............ ...................
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
IC' 'C' hrs
- in/hr
----------- acres
-------- cfs
--------- -- ac-ft
----- ac-ft
-----------
.608 .608 --------
-
.0833
7.5000
6.650
30.55 -----
.210 ---------
.107
.608 .608 .1667 6.1355 6.650 24.99 .344 .189
.608 .608 .2500 5.2500 6.650 21.39 .442 .235
.608 .608 .3333 4.6218 6.650 18.83 .519 .260
************************************************************ Storage Maximum
.608 .608 .4167 4.1659 6.650 16.97 .584 .274
****************************************************************************
.608 .608 .5000 3.7100 6.650 15.11 .624 .263
.608 .608 .6667 3.1511 6.650 12.84 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... Mod. Rational Storm Calcs Page 7.04
Name.... TRACT 2 AREA A Tag: 100-yr Event: 100 yr
File.... K:\01\01-110\01113\H&H\SWMP\PPW_WETLANDS\TRACT 2 WETLAND A.PPW
Storm... 100-yr IDF Table Tag: 100-yr
MODIFIED RATIONAL METHOD
---- Summary for Single Storm Frequency ----
Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600)
RETURN FREQUENCY: 100 yr 'C' Adjustment = 1.000Allowable Q 18.00 cfs
----------------------------------------------------------------------------
Hydrograph Storm Duration, Td = .5667 hrs Tc = .0833 hrs
Hydrograph File:
................ 100-yr
..........
...........
........
............
..........
.........
................ .......... ........... ........ ............ ...................
VOLUMES
Wtd. Adjusted Duration Intens. Area Qpeak Inflow Storage
'Cl 'C' hrs in/hr acres cfs ac-ft ac-ft
----------------
.608 .608 ----------
.0833 -----------
9.7200 --------
6.650 --------- --
39.59 I ----
.273
.149
.608 .608 .1667 8.4053 6.650 34.24 I .472 .286
.608 .608 .2500 7.2400 6.650 29.49 .609 .361
.608 .608 .3333 6.4676 6.650 26.35 .726 .416
.608 .608 .5000 5.2800 6.650 21.51 .889 .455
************************************************************ Storage Maximum
.608 .608 .5667 4.9606 6.650 20.21 .946 .463
.608 .608 .6667 4.4816 6.650 18.26 1.006 .448
.608 .608 .8333 3.8792 6.650 15.80 Qpeak < Qallow
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Type.... C and Area
Name.... TRACT 2 AREA#1
Page 7.05
File.... K:\01\01-110\01113\H&H\SWMP\PPW WETLANDS\TRACT 2 WETLAND A.PPW
RATIONAL C COEFFICIENT DATA
Area C x Area
Soil/Surface Description
-------------------------------- C
------ acres acres

Streets --
.9500 ----------
1.540 ----------
1.463.
Sidewalk .9500 .250 .238
Lots (impervious -W) .9500 1.740 1.653
Pervious
7 .2200 3.120 .686
WEIGHTED C & TOTAL AREA ---> .6075 6.650 4.040
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Elev. v;. Flaw
STAGE-DISCHARGE FUNCTION FOR OUTLETA
d
w
Hydrogrdph far 1-yr Design Storm
WETLAND IN w OUT
LL
Plotted Curves
OUTLET A
Plotted Curves
WETLAND A IN I-yr
WETLAND A OUT I-yr
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
0 10 20 30 40 50
Flow (cfs)
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E - PondPack Output for Wetland Design
Hydrograph for 2-yr Design Storm
WETLAND A IN %s OUT
LL
Hydrograph for 10-yr Design Storm
WETLAND IN %s OUr
N
LL
Plotted Curves
WETLANDA IN 2-yr
WETLANDA OUT 2-yr
Plotted Curves
WETLAND A IN 10-yr
WETLANDA OUT 10-yr
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
LONG LAKE SUBDIVISION - TRACT 2, PHASE 2
POND E -. PondPack Output for Wetland Design
Hydrograph for 100-yr Design Storm
WETLAND IN xe OUT
LL
Volume vs. Time
MINIMUM DRAIN TIME - Runoff from first 1' Rainfall
U
v
m
E
0
Plotted Curves
WETLAND A IN 100-yr
WETLAND A OUT 100-yr
Plotted Curves
MIN DRAIN OUT
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Time (hrs)
0 10 20 30 40 50 60 70
Time (hrs)
Michael F. Easley
Governor
William Ross, Secretary
Department of Environment and Natural Resources
Gregory J. Thorpe. PhD.
Acting Director
Division of Water Quality
December21, 2001
Wake County
DWQ Project # 01-1549
o?oF wArF,?QG
fl ?
e ,
APPROVAL of 401 Water Quality Certification and Additional Conditions, WRP, Neuse River Buffer Rules
Pulte Homes Corp.
Uci Gray Wthven
Director of Land
401 Harrison Oaks Blvd
Ste. 250
Cary, NC 27513
Dear Mr. Mcthven:
You have our approv-0, m module v.fth the attached conditions and those listed below, to place fill
material in 810 feet of screams bulim-ps t.raje u rpax d developing the Long Lake Subdivision in Wake County, as
de=led in your application rcc ed by fi-,e Dviezn of Water Quality on October 22, 2001. After reviewing your
aJptication, we have decided fha Us 0 is cx -ed by General Water Quality Certification Number 3289, which can
be viewed on our webs- at ht'DIAQo-L-r-ct;21--xic_mlmvetands. This certification allows you to use Nationwide
Permit Number 14 when the Cons of Engire.-ass ism iL This certification allows you to use the Neuse River Buffer
Pules (15A NCAC 26.0233). In addiiborL you stx i ge? any other federal, state or local permits before you go ahead
%1h your project including (not ftitt-d fo) Saar--it crud Erosion Control, Coastal Stormwater, Non-Discharge and
Water Supply Watershe regula o This z? rov-at vAI expire when the accompanying 404 or CAMA permit