20070218 Ver 1_More Info Received_20070418

..BLUE RIDGE
C O M P A N I E S, I N C.
Development Construction Management
April 16, 2007
Cyndi Karoly
401 Oversight
1650 Mail Service Center
Raleigh, NC 27699-1650
Re: Alexandria Park Apartments
Oak Hollow Lake[030608, 17-(3.3), WSIV]
Dear Ms. Karoly:
In response to your letter dated March 5, 2007, we have included the additional
information requested. In addition, please find the attached construction drawings and
applicable wet detention pond worksheets. We propose two wet detention ponds to
achieve nutrient removal and capture sediment from the impervious surfaces, including
the road crossing.
I trust this information satisfies your request and we look forward to your approval of this
project.
J
inc ely,
i Grdich
5826 Samet Drive • Suite 105 • High Point, NC 27265 • v.336.889.1500 • f.336.889.1501

OFFICE USE ONLY
Date Received Fee Paid Permit Number
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
This form maybe photocopied for use as an original
I. GENERAL INFORMATION
1. Applicants name (specify the name of the corporation, individual, etc. who owns the project):

2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance):
u~1~.1STot'1i-~2, t.1~•MJ'P~fdZ.- t d~kiJO~i~.3~ 1~.
3. Mailing Address for person listed in item 2 above:
SBZL ~~~'( pi~1,J~ ~•y,~l'I~ ~oS
City: ~llctta pbty'( State: rl~, Zip: 2?3.1~'S
Telephone Number: ('b3 V ) ~8 $g ~ 1511--
4. Project Name (subdivision, facility, or establishment name -should be consistent with project name on plans,
specifications, letters, operation and maintenance agreements, etc.): ,
Au~~t~F-~A- piia¢•t+~. ORD~R.t+~1 S
5. Location of Project (street address): - ,
r„ .~ ~~ _;~~,;
City: t~t,e~tJl 'p4.~'C County: 4JluPotUp
6. Directions to project (from nearest major intersection):
p~rax~w~,14tG-u.l~ ~'t•5 Ft S~'~ Ptr+an. Z•4~. t~Yt~-S~Tto.~ ~.
7. Latitude: 3t,',a1•~4" Longitude: '19~~g`2S~ of project
8. Contact person who can answer questions about the project
Name: SIEVE. v~3 ~ p.:-• Telephone Number: ('S'jb ) 812- ~$OC l~CC• 3~°
II. PERMIT INFORMATION: /
1. Specify whether project is (check one): / New Renewal Modification
Form SWU-101 Version 3.99 Page 1 of 4

2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the
existing permit number (!~A and its issue date (if known)
3. Specify the type of project (check one):
Low Density ~ High Density Redevelop General Permit Other
4. Additional Project Requ/irements (check applicable blanks):
CAMA Major / Sedimentation/Erosion Control /404/401 Permit / NPDES stormwater
Information on required state permits can be obtained by contacting the Customer Service Center at
1-877-623-6748.
III. PROJECT INFORMATION
1. In the space provided below, summarize how stormwater will be treated. Also attach a detailed narrative
(one to two pages) describing stormwater management for the project .
ML 'pto~C ~fll,.~,dio~ g~'L~C.~s 4S T~tK w.i~l~Q Fi•1 ~- SCt.'X~~• C~~tc,N4„»'
~~Zk.~ JMD 'mat "~'tt~K~C? Ys~r '~ C.'t•~ M~ iL'"C~-'~. t~ ~S
2. stormwater runoff from this project drains to the ~{~ fem. River basin.
3. Total Project Area: Z'0S•QO acres 4. Project Built Upon Area: 4l• ~
5. How many drainage areas does the project have? 'L
6. Complete the following information for each drainage area. If there are more than two drainage areas in the
project, attach an additional sheet with the information for each area provided in the same format as below.
Basin Information Drainage Area 1 Drainage Area 2
Receiving Stream Name vt 'v ~- t~~ "'~ 01~ S~ ~''~`~
Receiving Stream Class ~.1. ~3, vJS-1~ • ~?s•3 vJ5- lJ
Drainage Area • I,(, pti, 0.1 Pt•
Existing Impervious* Area ,p,.~ It. 2.1 lac.
Proposed Impervious*Area 5 , (~ i -~„ ~.. oo kt,
% Impervious" Area (total) ~, •oS Ic. • (t,~ •L '~ ~ • 1'3 ~.• (S'1. l '( •
Impervious* Surface Area Drainage Area 1 Drainage Area 2
On-site Buildings 1 • ar 7 ~,. t .~, Iwc.-
On-site Streets ,a IV ~~ o,e~ I„~,.
On-site Parking t •-t ~ ~, i , ~„
On-site Sidewalks o • S 1 1•C• o• 3~ k
Other on-site 1,1,E 1~,,
Off-site a.~' ~1C,. Z,.1~! -•~,
Total: q, •ess ~,, Total: 4.1'~i k.•
* Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas,
sidewalks, gravel areas, etc.
Form SWU-101 Version 3.99 Page 2 of 4

How was the off-site impervious area listed above derived? Ut*r ~G tlltrtl r''~tc`!l ~1~5 ~ P~~le-.1l~~~-
t ~o¢.wt.p={I,oJ
IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS
The following italicized deed restrictions and protective covenants are required to be recorded for all
subdivisions, outparcels and future development prior to the sale of any lot. If lot sizes vary significantly, a table
listing each lot number, size and the allowable built-upon area for each lot must be provided as an attachment.
1. The following covenants are intended to ensure ongoing compliance with state stormwater management permit number
as issued by the Division of Water Quality. These covenants may not be
changed or deleted without the consent of the State.
2. No more than square feet of any lot sha116e covered by structulrs or impervious materials.
Impervious materials include asphalt, gravel, concrete, brick, stone, slate or similar material but do not include wood
decking or the water surface of swimming pools.
3. Swales shall not 6e filled in, piped, or altered except as necessary to provide driveway crossings.
4. Built-upon area in excess of the permitted amount requires a state stormwater management permit modification prior to
construction.
5. All permitted runofffrom outparcels or future development shall be directed into the permitted stormwater control
system. These connections to the stormwater control system sha116e performed in a manner that maintains the integrity
and performance of the system as permitted.
By your signature below, you certify that the recorded deed restrictions and protective covenants for this project
shall include all the applicable items required above, that the covenants will be binding on all parties and persons
claiming under them, that they will run with the land, that the required covenants cannot be changed or deleted
without concurrence from the State, and that they will be recorded prior to the sale of any lot.
V. SUPPLEMENT FORMS
The applicable state stormwater management permit supplement form(s) listed below must be submitted for each
BMP specified for this project. Contact the stormwater and General Permits Unit at [phone] for the status
and availability of these forms.
Form SWU-102
Form SWU-103
Form SWU-104
Form SWU-105
Form SWU-106
Form SWU-107
Form SWU-108
Form SWU-109
Wet Detention Basin Supplement
Infiltration Basin Supplement
Low Density Supplement
Curb Outlet System Supplement
Off-Site System Supplement
Underground Infiltration Trench Supplement
Neuse River Basin Supplement
Innovative Best Management Practice Supplement
Form SWU-101 Version 3.99 Page 3 of 4

VI. SUBMITTAL REQUIREMENTS
Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ).
A complete package includes all of the items listed below. The complete application package should be
submitted to the appropriate DWQ Regional Office.
Please indicate that you have provided the following required information by initialing in the space provided
next to each item.
Init'als
• Original and one copy of the Stormwater Management Permit Application Form ~
• One copy of the applicable Supplement Form(s) for each BMP
• Permit application processing fee of $420 (payable to NCDENR) C
• Detailed narrative description of Stormwater treatment/management ~'
• Two copies of plans and specifications, including:
- Development/Project name
- Engineer and firm
-Legend
- North arrow
- Scale
- Revision number & date
- Mean high water line
- Dimensioned property/project boundary
- Location map with named streets or NCSR numbers
- Original contours, proposed contours, spot elevations, finished floor elevations
- Details of roads, drainage features, collection systems, and stormwater control measures
- Wetlands delineated, or a note on plans that none exist
- Existing drainage (including off-site), drainage easements, pipe sizes, runoff calculations
- Drainage areas delineated
- Vegetated buffers (where required)
VII. AGENT AUTHORIZATION
If you wish to designate authority to another individual or firm so that they may provide information on your
behalf, please complete this section.
Designated agent (individual or firm): c.p'( Es„-4t.S~Rt~ S SJR.J~ttJ~ ; n3C (~i'~' v.X~+S[i•• ~ P~
Mailing Address: 4d °Q "M ~ll~ StR~'f
City: 4lttttl~ 'R~~'( State: ~~. Zip: Z7't6'S
Phone: (?i'3~• ) X12- 28og E1tC. 3to
VIII. APPLICANT'S CERTIFICATION
Fax: ('~3tr ) ~ i'L ^ 4Ci ~ o
I, (print or type name of person listed in General Information, item 2) uiQ.kStop~. t• W~~R•
certify that the information included on this permit application form is, to the best of my knowledge, correct and
that the project will be constructed in conformance with the approved plans, that the required deed restrictions
and protective covenants will be recorded, and that the proposed project complies with the requirements of 15A
NCAC 2H .1000 ~ /1
Signature:.
7.
Date: 7' • ~• ~ 7
Form SWU-101 Version 3.99 Page 4 of 4

Permit No.
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
(to be provided by DWQ)
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form maybe photocopied for use as an original
DW Stormwater Management Plan Review:
A complete stormwater management plan submittal includes an application form, a wet detention basin
supplement for each basin, design calculations, and plans and specifications showing all basin and outlet
structure details.
I. PROJECT INFORMATION
Project Name: A~xeaJvQ.~P~ POt~.k. AdPA~cttw-Qti.1'C~
Contact Person: ~w~ 4yotca.~ Phone Number: (33l.) X89 ~ tSIZ
For projects with multiple basins, specify which basin this worksheet applies to: 1
,.
elevations
Basin Bottom Elevation Q~Z ft.
Permanent Pool Elevation ®~'1 ft.
Temporary Pool Elevation $•Lq ft.
(floor of the basin) °~
(elevation of the orifice)
;,~:
(elevation of the discharge structure overflow) ~~"~`
areas
Permanent Pool Surface Area ~2 ~{r13 sq. ft. (water surface area at the orifice elevation)
Drainage Area 9~`t+ ac. (on-site and off-site drainage to the basin)
Impervious Area ~.oS ac. (on-site and ofd=site drainage to the basin)
volumes
Permanent Pool Volume 31 ~ S9~ cu. ft. (combined volume of main basin and forebay)
Temporary Pool Volume , 21., 9 ~'1 cu. ft. (volume detained above the permanent pool)
Forebay Volume tS . ~ 1'1 cu. ft. (approximately 20% of total volume)
Other parameters
SAlDAI
Diameter of Orifice
Design Rainfall
Design TSS Removal 2
~.zIS
z.o
~.o
(surface area to drainage area ratio from DWQ table)
in. (2 to S day temporary pool draw-down required)
in.
85 % (minimum 85% required)
Form SWU-102 Rev 3.99 Page 1 of 4

Footnotes:
1 When using the Division SA/DA tables, the correct SA/DA ratio for permanent pool sizing should be computed based upon the
actual impervious % and permanent pool depth. Linear interpolation should be employed to determine the correct value for non-
standard table entries.
2 In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide
90%TSS removal. The NCDENR BMP manual provides design tables for both 85%TSS removal and 90% TSS removal.
II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Code
Section: 15 A NCAC 2H .1008.
Initial in the space provided to indicate the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. If a requirement has not been met, attach justification.
Applicants Initials
S~G-J a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
S~CW b. The forebay volume is approximately equal to 20% of the basin volume.
St~,J c. The temporary pool controls runoff from the design storm event.
SG~,1 d. The temporary pool draws down in 2 to 5 days.
c~-wJ e. If required, a 30-foot vegetative filter is provided at the outlet (include non-erosive flow
calculations)
SG,J f. The basin length to width ratio is greater than 3:1.
StW g. The basin side slopes above the permanent pool are no steeper than 3:1.
s~WJ
h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail).
~,! i. Vegetative cover above the permanent pool elevation is specified.
S'wJ j. A trash rack or similar device is provided for both the overflow and orifice.
5'~ k. A recorded drainage easement is provided for each basin including access to nearest right-
of-way. Cw~w~„ a~c+At~ ~artc~. -ce tssw+.x~ d~- &.x~D-~ Cpi~
S'G~ 1. If the basin is used for sediment and erosion control during construction, clean out of the
basin is specified prior to use as a wet detention basin.
Stt~.J m. A mechanism is specified which will drain the basin for maintenance or an emergency.
III. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the
vegetated filter if one is provided.
This system (check one) A'does 0 oes not incorporate a vegetated filter at the outlet.
This system (check one) 0 does A'does not incorporate pretreatment other than a forebay.
Form SWU-102 Rev 3.99 Page 2 of 4

• Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to maintain
proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed of
in an appropriate manner and shall be handled in a manner that will not adversely impact water quality (i.e.
stockpiling near a wet detention basin or stream, etc.).
'The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
When the permanent pool depth reads 4 feet in the main pond, the sediment shall be removed.
When the permanent pool depth reads 4 feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
0 Permanent Pool Elevation $~'1
Sediment Re oval El. $43 ---- 75 0
__________ Sediment Removal Elevation $~ 75%
Bottom Ele ation ~~ % ------------------------------------------- ---o -
Bottom Elevation 8~Z- 25 /o
FOREBAY
MAIN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment through
the emergency drain shall be minimized to the maximum extent practical.
Form SWU-102 Rev 3.99 Page 3 of 4

7. All components of the wet detention basin system shall be maintained in good working order.
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Print name: u~-¢~s ~~ o~a3~- C"e~-c. W~4~2~ ~~d..~ ~l.C
Title: L~K.S'~teuk, ru.-
Address: ~8zt, ~•.`'t ~~ ~ s~~'c+5 t~ acq~l 'P~c31. ~1 c. -t.~(zt.5
Phone
Signat
Date: ~• 5.0 7
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a
resident of the subdivision has been named the president.
I, ~b•G.~ct ~ ~ , a Notary Public for the State of J/o,-f~, G~.r o 1; .. ~ ,
County of ~ a v : ~ s o ~ , do hereby certify that G hr: sfo pie ~ 7 Du, >, ba ,~
personally appeared before me this 5 day of 1lpr: I boa 1 .and acknowledge the due
execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal,
~.
~~+ ~ ~jes
~' .~, s
~ ~Q7~`~
~u
A
4
=' ~~ A~~„1C t.~ d
P P ® ~ ~~
pyd~Yd3 Pd tt LL {1~,~
SEAL
My commission expires ~ 0 ' 7 ' D ~
Form SWU-102 Rev 3.99 Page 4 of 4

WATERSHED DEVELOPMENT,
STORMWATER,
AND
EROSION CONTROL CALCULATIONS
FOR
ALEXANDRIA PARK APARTMENTS
NC HWY 68 & WHITES MILL ROAD
HIGH POINT, NORTH CAROLINA
DEVELOPER/ OWNER:
Blue Ridge Companies, Inc.
5826 Samet Drive
Suite 105
High Point, North Carolina 27265
[phone]
CPT Engineering and Surveying, Inc.
3935 Brian Jordan Place -Suite 137 • High Point, NC 27265 • Phone [phone] • Fax [phone]
_. "~;:{

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1
1

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SITE LOCATION
USGS MAP
SOILS SURVEY MAP

1IrB
t
-Tic_- - -
_
1 Deep River
t
s _ MOB _
AOS
j SITE)
1+r1D
REF: 501L SIAVEY OF 501L TYPES:
GUILFORD COUNTY, NG Gh Cheiaacla sandy loan
UNITED STATES DEPARTMENT OF AGRICULTURE EnS Enon fine sandy loan, 2 to 6 percent slopes
SOILS CONSERVATION SERVICE EnD Enon fine sandy loam, 10 to 15 percent elopes
DECEMBER 141'17
EN61NEERIN6 AND SURVEYING, INC. ALL.XANPRIA PAR`-< APA,- bNTS
D LAND DEVELOPMENT CONSULTIN6
SOIL- 5UPZVEY' MAP
4400 TYNIN6 STREET 6U1� i '��®UNi�', NC�5 H16H POINT, NORTH CAROLINA 27265
PHONE: [phone] — FAX: [phone] SCALE: I"=1000' (D

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1
1

1

1
1

STORM DRAINAGE
CALCULATIONS

CPT Engineering and Surveying, Inc.
3935 Brian Jordan Place, Suite 137
' High Point, N.C. 27265
~ TABLE 1. INPUT

1
1
1

Location: Hi h Poin t, North Ca rolina
Duration: 2 yr
in 100 yr
in) Source
5 min 0.47 0.82 NOAH H dro 35
15 min 0.92 1.71 NOAH H dro 35
60 min 1.59 3.30 NOAH H dro 35
24 hr 3.50 7.50 USWB TP 40
TABLE 2. DEPTH -DURATION -FREQUENCY
Duration
H-1 * 2 yr
in 5 yr
(in) 10 yr
in 25 yr
in 50 yr
in 100 yr
in
5 min * 0.47 0.54 0.60 0.69 0.75 0.82
10 min 0.74 0.87 0.97 1.12 1.23 1.35
15 min * 0.92 1.10 1.22 1.41 1.56 1.71
30 min 1.25 1.53 1.74 2.03 2.26 2.49
60 min * 1.59 1.99 2.27 2.67 2.99 3.34
2 hr ~' 1.80 2.26 2.58 3.04 3.40 3.76
3 hr * 2.01 2.53 2.89 3.41 3.82 4.22
6 hr * 2.55 3.22 3.69 4.36 4.88 5.40
12 hr * 3.02 3.83 4.40 5.20 5.83 6.45
24 hr ~` 3.50 4.44 5.10 6.04 6.77 7.50
From Eqs. lll-(7-3), p.lll-(4-5), stormwater Managemenr: voi.~
Urban Hydrology. B. H. Bradford, N. S. Grigg, L.S. Tucker
TABLE 3. INTENSITY -DURATION -FREQUENCY
i

1
1

Duration 2 yr
in/hr 5 yr
in/hr 10 yr
in/hr 25 yr
in/hr) 50 yr
in/hr 100 yr
in/hr
5 min 5.64 6.54 7.22 8.24 9.04 9.84
10 min 4.41 5.22 5.81 6,69 7.38 8.07
15 min 3.68 4.38 4.90 5.65 6.25 6.84
30 min 2.50 3.07 3.47 4.06 4.52 4.98
60 min 1.59 1.99 2.27 2.67 2.99 3.30
2 hr 0.90 1.13 1.29 1.52 1.70 1.88
3 h r 0.67 0.84 0.96 1.14 1.27 1.41
6 hr 0.42 0.54 0.61 0.73 0.81 0.90
12 hr 0.25 0.32 0.37 0.43 0.49 0.54
24 hr 0.15 0.19 0.21 0.25 0.28 0.31
Intensity =Depth /Time
1

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ i i ~ ~ ~ ~ ~
Storm DraineBe Desimn Data Sheet
Pipe-Sizing Table for Conventional Method
Project Alexandria Park Apartments
Location: High Point, N.C.
Storm Frequency: 10 Year
Description: Sturm Drainage Draining to Wet Detention Pond # 1
Computed By: STW Date: 11/29/06
Checked By: Revised: 1/ 19/07
Location Area Tc C Intensity Q=CIA n Pi Dtheo. Size Vfull Inv. In Inv. Out HW JD
From To Sub Total min in hr cfs Slo Le in in ft sec ft ft
CB #1 EX SDMH 0.25 0.25 5.00 0.80 7.22 1.44 0.013 0.0630 I1 6.05 15 13.19 --- 879.3 0.54
EX SDMH SDMH #2 --- 0.25 5.00 0.80 7.22 1.44 0.013 0.0560 219 6.19 18 14.05 --- 878.4 <0.50
SDMH #2 CI #3 --- 0.25 5.00 0.80 7.22 1.44 0.013 0.0670 I5 5.98 18 15.37 866.1 (EX 18' RCP) 865.3 <0.50
CI #3 CI #5 0.24 0.49 5.00 0.80 7.22 2.83 0.013 0.0100 31 11.00 16 5.94 864.3 864.1 0.61
DI #4 CI #5 1.36 1.36 5.00 0.80 7.22 7.86 0.013 0.0100 39 16.13 18 5.94 --- 864.2 1.20
CI #5 CB #6 0.25 2.10 5.00 0.80 7.22 12.13 0.013 0.0320 56 15.26 24 12.86 863.8 (CI #3) 863.3 0.98
863.8 (DI #4)
CB #6 CH #8 0.07 2.17 5.00 0.80 7.22 12.53 0:013 0.0050 138 21.88 24 5.09 861-5 861.0 0.99
YD #7 CB #8 0.14 0.14 5.00 0.80 7.22 0.81 0.013 0.0100 49 6.87 S 3.46 --- 863.5 ---
CB #8 CB #10 0.30 2-61 5.00 0.80 7.22 15.08 0.013 0.0050 90 23.45 30 5.90 860.3 (CB #6) 859.8 0.76
863.0 (YD #7)
DI #9 CH #10 0.25 0.28 5.00 0.80 7.22 1.62 0.013 0.0190 112 7.90 15 7.25 -- 865.5 0.57
CB #10 CB #14 0.44 3.33 5.00 0.80 7.22 19.23 0.013 0.0050 199 25.69 30 5.90 859.3 (CB #8) 859.1 0.90
863.4 (DI #9)
Dl #l l DI #12 0.7fi 0.76 5-00 0.80 7.22 4.39 0.013 0.0840 57 8.70 15 15.24 -- 869.5 1.08
DI #12 CB #14 0.52 1.28 5.00 0.80 7.22 7.39 0.013 0.0100 186 15.76 18 5.94 864.7 864.5 1.14
YD # 13 CB # 14 0.10 0.10 5.00 0.80 7.22 0.58 0.013 0.0110 35 5.95 8 3.63 -- 863.7 ---
CB # 14 CB # 17 0.55 5.26 5.00 0.80 7.22 30.38 0.0 i3 0.0050 187 30.50 36 6.66 858.1 (CB # 10) 857.6 0.90
862.6 (DI #12)
863.3 (YD #13)
DI #15 CB #16 0.26 0.26 5.00 0.80 7.22 1.50 0.013 O.OlOD 67 8.67 IS 5,26 --- 862.4 0.54
CB # 16 CB # 17 0.21 0.47 5.00 0.80 7.22 2.71 0.013 0.0100 60 10.83 15 5.26 861.5 861.3 0.78
CB #17 CB #27 0.47 6.20 5.00 0.80 7.22 35.81 0.013 0.0060 50 31.35 36 7.30 856.6 (CB #14) 856.4 1.01
860.7 (CB #16)
YD # 18 CB # 19 0.12 0.12 5.00 D.80 7.22 0.69 0.013 0.0110 114 6.37 8 3.63 --- 863.5 ---
CB #19 CB #22 0.38 0.50 5.00 0.80 7.22 2.89 0.013 0.0160 56 10.15 15 6.65 862.2 861.6 0.80
YD #20 DI #21 0.13 0.13 5.00 0.80 7.22 0.75 0.013 0.0100 154 6.69 8 3.46 --- 862.9 ---
DI #21 CB #22 0.16 0.29 5.00 0.80 7.22 1.68 0.013 0.0100 95 9.03 IS 5.26 861.3 860.7 0.58
CB #22 CB #23 0.34 1.13 5.00 0.80 7.22 6.53 0.013 0.0110 i7 14.78 18 6.23 560.7 (CB #19) 859.5 1.03
859.7 (DI #21)
CB #23 CB #26 0.18 1.31 5.00 0.80 7.22 7.57 0.013 0.0100 121 15.90 18 5.94 859.3 859.1 1.16
YD #24 DI #25 0.17 0.17 5.00 0.80 7.22 0.98 0.013 0.0100 89 7.39 8 3.46 --- 861.8 ---
DI #25 CB #26 0.06 0.23 5.00 0.80 7.22 1.33 0.013 0.0100 64 8.28 IS 5.26 860.9 860.3 0.52
CH #26 CB #27 0.32 1.86 5.00 0.80 7.22 10.74 0.013 0.0060 125 19.96 24 5.57 857.9 (CB #23) 857.4 0.88
859.6 (DI #25)
CB #27 CB #30 0.33 8.39 5.00 0.80 7.22 48.4b 0.013 p.0050 144 36.33 36 6.66 856.1 (CB #17) 855.9 1.29
856.7 (CB #26)
DI #28 DI #29 0.11 0.11 5.00 0.80 7.22 0.64 0.013 0.0300 100 5.11 15 9.1 L --- 861.2 <0.50
DI #29 CB #30 0.19 0.30 5.00 0.80 7.22 1.73 0.013 0.0100 85 9.15 15 5.26 858.2 858.0 0.59
CB #30 FES #31 0.43 9.12 5.00 0.80 7.22 52.68 0.013 0.0100 58 32.92 36 9.42 855.1 (CB #27) 847.6 1.40
857.1 (DI #29)
CPT Engineering and Surveying, Inc. Page 1

~ ~ ~ ~ ~ ~ ~ ~ i ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Description: Storm Drainage Draining to Wet Detention Pond #2
Location Area Tc C Intensity Q=CIA n Pie Dtheo. Size Vfull Inv. In Inv. Out HW/D
From To Sub Total min in hr cfs Sloe Len in in ft sec ft ft
CI #32 EX YI 0.07 0.07 5.00 0.80 7.22 0.40 0.013 0.0830 30 3.56 15 15.14 --- 870.5 <0.50
DI #33 DI #34 0.22 0.22 5.00 0.80 7.22 1.27 0.013 0.0100 150 8.14 15 5.26 --- 863.9 0.50
DI #34 CB #35 0.13 0.35 5.00 0.80 7.22 2.02 0.013 0.0100 59 9.69 15 5.26 862.4 862.2 0.65
CB #35 CB #39 0.01 0.36 5.00 0.80 7.22 2.08 0.013 0.0100 149 9.80 15 5.26 861.6 861.4 0.66
YD #36 CB #39 0.03 0.03 5.00 0.80 7.22 0.17 0.013 0.0160 110 3.53 6 3.61 --- 863.5 ---
CI #37 CI #38 0.63 0.63 5.00 0.80 7.22 3.64 0.013 0.0100 30 12.08 15 5.26 --- 861.0 0.95
CI #38 CH #39 0.53 1.16 5.00 0.80 7.22 6.70 0.013 0.0100 133 15.19 18 5.94 860.7 860.5 1.05
CB #39 DI #40 0.49 2.04 5.00 0.80 7.22 11.78 0.013 0.0050 157 21.38 24 5.09 859.9 (CB #35) 858.6 0.94
861.7 (YD #36)
859.1 (CI #38)
D[ #40 CB #46 0.14 2.18 5.00 0.80 7.22 12.59 0.013 0.0050 74 21.92 24 5.09 857.8 857.6 1.00
CB #41 CB #42 0.20 0.20 5.00 0.80 7.22 1.16 0.013 0.0150 85 7.28 15 6.44 --- 861.6 <0.50
CB #42 CB #46 0.73 0.93 5.00 0.80 7.22 5.37 0.013 0.0170 129 12.66 15 6.85 860.3 860.1 1.29 i
YD #43 CB #46 0.03 0.03 5.00 0.80 7.22 0.17 0.013 0.0100 99 3.86 6 2.85 --- 860.7 ---
CB #44 CB #45 0.15 0.15 5.00 0.80 7.22 0.87 0.013 0.0100 50 7.05 15 5.26 --- 853.6 <0.50
CB #45 CB #46 0.02 0.17 5.00 0.80 7.22 0.98 0.013 0.0100 54 7.39 15 5.26 853.1 852.9 <0.50
CB #46 DI #47 0.37 3.68 5.00 0.80 7.22 21.26 0.013 0.0050 190 26.67 30 5.90 857.2 (DI #40) 851.1 0.97
857.9 (CB #42)
859.7 (YD #43)
852.3 (CB #45)
DI #47 CB #48 0.17 3.85 5.00 0.80 7.22 22.24 0.013 0.0060 67 26.22 30 6.46 850.1 850.0 1.02
CB #48 CH #56 0.36 4.21 5.00 0.80 7.22 24.32 0.013 0.0050 187 28.05 30 5.90 849.6 849.5 1.09
CB #49 DI #50 0.34 0.34 5.00 0.80 7.22 1.96 0.013 0.0100 49 9.59 15 5.26 --- 861.3 0.64
DI #50 DI #51 0.17 0.51 5.00 0.80 7.22 2.95 0.013 0.0100 135 11.16 15 5.26 560.8 860.6 0.81
DI #51 CB #52 0.13 0.64 5.00 0.80 7.22 3.70 0.013 0.0100 123 12.16 15 5.26 859.2 859.0 0.96
CB #52 CB #53 0.14 0.78 5.00 0.80 7.22 4.51 0.013 0.0120 105 12.65 15 5.76 857.7 857.5 1.12
CB #53 CB #56 0.61 1.39 5.00 0.80 7.22 8.03 0.013 0.0330 115 13.00 18 10.78 856.2 855.2 1.24
EX C[ CB #54 3.04 3.04 5.00 0.80 7.22 17.56 0.013 0.0270 15 18.10 24 11.82 850.7 850.6 1.30
CB #54 CB #55 --- 3.04 5.00 0.80 7.22 17.56 0.013 0.0090 22 22.24 24 6.82 550.2 850.0 1.30
CB #55 CB #56 0.08 3.12 5.00 0.80 7.22 18.02 0.013 0.0060 54 24.23 30 6.46 849.8 849.3 0.86
CB #56 DI #57 0.31 9.03 5.00 0.80 7.22 52.16 0.013 0.0050 15 37.35 36 6.66 848.5 (CB #48) 848.0 1.40
851.4 (CB #53)
849.0 (CB #55)
DI #57 DI #58 0.06 9.09 5.00 0.80 7.22 52.50 0.013 0.0050 90 37.44 36 6.66 847.9 847.8 1.40
DI #58 FES #59 0.04 9.13 5.00 0.80 7.22 52.73 0.013 0.0060 31 36.24 36 7.30 847.3 847.2 1.40
Description: Off-site drainage from Lot 3 (PB 97 PG 109) and Lot X (church properly) to by-pass site
Location Area Tc C Intensity Q=CIA n Pie Dtheo. Size Vfull Inv. In Inv. Out HW/D
From To Sub Total min in hr cfs Slo Len th in in ft sec ft ft
DI #60 SDMH #61 2.03 2.03 5.00 0.80 7.22 11.73 0.013 0.0120 34 18.11 24 7.88 861.4 (EX 18" RCP( 559.3 0.94
SDMH #61 FES #62 4.79 6.82 5.00 0.80 7.22 39.39 0.013 0.0110 73 29.00 36 9.88 858.9 (DI #60) 856.8 1.09
860.5 (EX 30" RCP(
CPT Engineering and Surveying, Inc. Page 2

Description: Culvert under private drive
Location Area Tc C Intensity Q=CIA n Pi Dtheo. Size Vfull Inv. In Inv. Out HW/D
From To Sub Total min in hr cfs Slo Le in in ft sec ft ft
Inlet Outlet 8.26 8.26 5.00 0.80 7.22 47.71 0.013 0.0110 53 31.16 36 9.58 845.0 844.4 1.30
Description: Off-site drainage from the north side of Whites Mill Road to by-pass site
Location Area Tc C Intensity Q=CIA n 1'i Dtheo. Size Vfull Inv. In Inv. Out I-IW/D
From To Sub Total min in hr cfs Slo Le in in ft sec ft ft
SDMH #63 SDMH #64 8.90 8.90 5.00 0.80 7.22 51.41 0.013 0.0050 60 37.15 36 6.66 847.6 846.0 1.40
SDMH #64 SDMH #65 --- 8.90 5.00 0.80 7.22 51.41 0.013 0.0050 233 37.15 36 6.66 845.7 845.6 1.40
SDMH #65 FES #66 --- 8.90 5.00 0.80 7.22 51.41 0.013 0.0060 50 35.90 36 7.30 844.4 844.3 1.40
CPT Engineering and Surveying, Inc. Page 3

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168. 8,p00 EXAMPLE I ~) (^L ) (3)
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'~tesrr~t 6i`~atex• ~;e~r~~~c~c~,ti

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t

EROSION CONTROL CALCULATIONS
SEDIMENT BASIN DESIGN
OUTLET PROTECTION

Sediment Basin Design
Project: Alexandria Park Apartments Computed By: STW Date: 12/15/06
Location: High Point, N.C. Checked By: STW Revised: 02/05/07
Developer. Blue Ridge Companies, Inc.
Design Criteria: Settling Efficienry Criteria:
Design Storm 10 yr Design Storm 10 yr
Rational Runoff Coef£ 0.50 Rational Runoff Coef£ 0.50
Intensity 5.81 in/hr (Tc= 10 min,) Intensity 5.81 in/hr (Tc= 10 min.)
Weir Coefficient 2.5
Height Over Weir 1 ft

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Bottom Bottom Top Top Side- Weir
Basin Drainage Denuded Sediment Basin Width Length Depth Width Length slope Length
Number Area (Acres) Area (Acres) Volume ft. ft. ft. ft ft. ft.
R aired Provided
1 3.44 3.44 12,384 13,589 See Grading Plan 3 See Grading Plan 2 5
2 4.38 4.38 15,768 17,609 See Grading Plan 3 See Grading Plan 2 5
3 7.70 7.32 26,352 27,417 See Grading Plan 3 See Grading Plan 2 9
10-year Bottom Bottom Top Top Side-
Basin Drainage Peak Inflow Surface Area Width Length Depth Width Length slope
Number Area (Acres) (cfs) S . ft. ft. ft. ft. ft ft.
Re aired Provided
1 3.44 9.99 4,347 5,467 See Grading Plan 3 See Grading Plan 2
2 4.38 12.72 5,535 7,251 See Grading Plan 3 See Grading Plan 2
3 7.70 22.37 9,730 12,736 See Grading Plan 3 See Grading Plan 2
Basin #k Elevation Area
s Volume
c Total
Volume cf)
1 850 3,621
852 4,823 8,444
853 5,467 5,145 13,589
2 849 4,546
850 5,390 4,968
852 7,251 12,641 17,609
3 846 5,048
848 10,667 15,715
849 12,736 11,702 27,417

Appendices
~?
_; ~ ~....
vJID'~ m °l~ k'z3~
~ 4ti~c.at~ S ° 18 K
cis s i W P~1h~'
a n ~~
+-
a~
~ _N
Cn
d
(LS
a
0
ate,=o•4
Discharge (ft3/sec)
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from a round pipe flowing full, minimum tailwater condition (TW < 0.5 diameter).
Rcv. 123 8.06.3

Appendices
~,
_r ~:
Pfa'
OrPttc~J vJ ~q'~l :. 9 ~x 23
kptLo~J 'Ca{ l c.ka..9~ ~ s ! ~', ~ 1
~ ~~ i Qt PQ~&'
Z n ~T
Discharge (ft3/sec)
N
N
r
d
(>3
Q.
O
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from a round pipe flowing full, minimum tailwater condition (Tw < 0.5 diameter).
Rcv. 1293 8.06.3

~ippendices
r~~ LZ~13V'~9~~
Cnro~ v.~~p~ ~ Q`x 23`
?t~~ 4s.f l ~ 18"
~n_ ~T
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1
m
N
7
Q
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Q
O
1000
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from around pipe flowing full, minimum tailwater condition (TW < 0.5 diameter).
12cv. 12,93 8.06.3
3 5 10 20 50 100 200 500
Discharge (ft3/sec)

Appendices
~:,.
Q~a~.3 ~(t ~.w3~ z ~ $ "
3 0 ~ iii n~
~ ~~,,
,,iii ~ j' I' !~~
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diameter (Do) ~ ~ ~ j ~ it I ~ ! ~.~ ~ j,. ~ ; ~,
80 ~
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10
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Discharge (ft3/sec)
a~
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lr
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1000
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from a round pipe flowing full, minimum tailwater condition (TW < 0.5 diameter).
~Ppto60 ,~~; ~ ` I
`r0 ~ j ~i I~:! lil I `
erg ~i , (~ l,l:l~~ I
(~~ 5Q ,1 I JII ' ~ ~ t Irlj 1~ ~ `
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Appendices
GV L~~~ ~ ~ 3 L ~~ ~~ I
pcpc~e..l c.E~4"~l t ZOO
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ctS
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~~~~.~,
Curves may not be extrapolated.
Figure 8.06a Design of outlet protection protection from a round pipe flowing full, minimum tailwater condition (TW < 0.5 diameter).
Rcv. 12x93 8.6.3
Discharge (ft3/sec)
4 "1 7 t c:{S

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tmp#4.txt
culvert Calculator
Entered Data:
Shape .. ..... .................
Number of~Barrels ...............
Solving for .....................
chart Number ....................
Scale Number .................
Chart Description ...............
ENTRANCE
Scale Deccription ...............
Overtopping. .....................
Flowrate ........................
Manning's n .....................
Roadway Elevation ...............
Inlet Elevation .................
outlet Elevation ................
Diameter ........................
Length .......................
Entrance~LOSS ............ .....
Tailwater .......................
Circular
1
Headwater
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CONCRETE PIPE CULVERT; NO BEVELED RING
SQUARE EDGE ENTRANCE WITH HEADWALL
off
47.7100 cfs
0.0130
857.0000 ft
845.0000 ft
844.4000 ft
3.0000 ft
53.0000 ft
0.0000
0.1000 ft
Computed Results:
Headwater ....................... 848:8588 ft Inlet Control
slope .~ ......................... 0.0113 ft/ft
velocity ........................ 10.7663 fps
Messages:
Inlet head > Outlet head.
Computing Inlet Control headwater.
solving Inlet Equation 26.
Solving Inlet Equation 28.
Headwater: 848.8588 ft
Page 1

WET DETENTION POND DESIGN
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I_'

Im envious Surface Area Allocation
Area Existing. ISA' Net ISA AlfowedZ Max. ISA Allowed Proposed fSA
Lot Y: (Zoning Tract A)
Tier 3
Tier 4
1.260 Ac.
1.229 Ac.
0.19 Ac.
0.16 Ac.
0.37 Ac.
0.53 Ac.
0.56 Ac.
0.69 Ac.
0.72 Ac.
0.80 Ac.

LOt W: (Zoning Tract B)
Tier 3
Tier 4
17.694 Ac.
2.817 Ac.
0.50 Ac.
0.52 Ac.
6.02 Ac.
1.15 Ac.
6.52 Ac.
1.67 Ac.
6.36 Ac.
1.56 Ac.3

Development Total:4
Tier 3
Tier 4
18.954 Ac.
4.046 Ac.
0.69 Ac.
0.68 Ac.
6.39 Ac.
1:68 Ac.
7.08 Ac.
2.36 Ac.
7.08 Ac.
2.36 Ac.
Total 23.000 Ac. 1.37 Ac. 8.07 Ac. 9.44 Ac. 9.44 Ac.
Notes:
1. 100% of the existing iSA is grandfathered and added to the net ISA allowed.
2. The net ISA is the area within each respective tier minus the existing ISA within that tier times the maximum percentage ISA of that tier.
3. Includes proposed public road and sidewalk.
4. The development total is for Lots Y and W.

i

Stormwater Management Summary
Site Area' 23.000 Ac.
Existing ISA 1.37 Ac.
Proposed ISA 9.44 Ac.
WET C3ETEN7"IUN PQN~ ' #'I
On-Site D.A. to Pond #1 9.13 Ac.
Off-Site D.A. to Pond #1 0.53 Ac.
otai D.A. to Pond #1 9.66 Ac.
OnSite ISA draining to Pond #1 3.82 Ac.
Future OnSite ISA draining to Pond #1 1.69 Ac.2
Off-Site ISA drainin to Pond #1 0.44 Ac.~
Total ISA draining to Pond #1 6.05 Ac.
Max. ISA Per Pond Desi ns 6.28 Ac. 65.0%
INET DETENTION PONQ #2
OnSite D.A. to Pond #2 7.67 Ac.
Off-Site D.A. to Pond #2 3.06 Ac.
otal D.A. to Pond #2 10.73 Ac.
On-Site ISA draining to Pond #2 4.00 Ac.
Off-Site ISA drainin to Pond #2 2.13 Ac.S
Total ISA draining to Pond #2 6.13 Ac.
Max. ISA Per Pond Designs 6.44 Ac. 60.0%
Notes:
1. The site area is the total development area for Lot Y (commercial site) and Lot W (apartment site).
2. Pond #1 has been designed to treat 1.69 Ac. ISA from Lot Y (commercial site).
' 3. Off-site ISA to Pond #1 includes approximately 0.44 Ac. from Eastchester Drive (NC Hwy 68).
4. Max. ISA per the pond design is the ISA within the pond's drainage area.
5. Off-site ISA to Pond #2 includes approximately 1.44 Ac. from Lot 3 (PB 97 PG 109) and
approximately 0.69 Ac. from Whites Mill Road.

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Alexandria Park Apartments
Wet Detention Pond #1 Date: December 8, 2006
Revised: April 16, 2007
Summary of Results
Pre-Development Post Development
Peak Flow Peak Flow Post Development
Design Storm (cfs) (cfs) W.S. Elevation
10-year 24.42 20.13 850.69
100-year 45.41 57.02 851.85

Alexandria Park Apartments
Wet Detention Pond #2
Summary of Results
Date: December 11, 2006
Revised: April 16, 2007
Pre-Development Post Development
Peak Flow Peak Flow Post Development
Design Storm (cfs) (cfs) W:S. Elevation
10-year 24.24 9.85 850.04
100-year 42.77 34.76 851.43

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3. Genera}
a. Basin shape should nunimize dead storage areas and short circuiting. Length to width
ratios should be 3:1 or greater. (Barfield, el al., 1981, pp. 426,429; Florida DEP, 1982,
pg. 6-289).
b. ff the basin is used as a sediment trap during construction, all sediment deposited during
construction must be removed before normal operation begins.
c. Aquatic vegetation should be included for a wetland type detention basin (Maryland
DNR, March 1987; Scheeler, 1987, Chapter 4 and 9). A minimum ten foot wide shallow
sloped shelf is needed at the edge of the basin for safety and to provide appropriate
conditions for aquatic vegetation (Scheeler, 1987). This shelf should be sloped 6:1 or
flatter and extend to a depth of 2 feet below the surface of the permanent pool (Shaver
and Maxted, DNREC, 1994). A list of suitable wetland species and propagation
techniques are provided in Scheeler (1987) and Maryland DNR (1987).
d. An emergency drain (with a pipe sized to drain the pond in less than 24 hours) should be
installed in all ponds to allow access for riser repairs and sediment removal (Scheeler,
1987}.
Table 1:1 Surface Area to Drainage Area Ratio For Permanent Pool Sizing For 85 °k Pollutant
Removal Efficiency in the Piedmont
°,b Impervious
Cover 3.0 4.0 5.0 6.0 7.0 8.0 9.0

20 0.97 0.79 0.70 O.S9 0.51 0.46 0.44
30 1.34 1.08 0.97 0.83 :70 0.64 0.62
40 1.73 1.43 .2 1.05 0.90 0.82. 0.77
50 2. 1.73 1:50 1.30 1.09 1.00 0.92
60 2.40 2.03 1.71 LS1 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
Notes: Numbers given in the body of the table are given in percentages.
Coastal SA/DA ratios can be obtained from the local DWQ Regional Office.

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WET DETENTION POND DESIGN
WET DETENTION POND #1
PRE-DEVELOPMENT
HYDROLOGIC ANALYSIS

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Tabte of Contents
Table of Contents
i
********************** MASTER SUMMARY **********************
Watershed....... Master Network Summary ............. 1.01
*************** NETWORK SUMMARIES (DETAILED) ***************
Watershed....... Pre.10
Executive Summary (Nodes) .......... 2.01
Watershed....... Pre100
Executive Summary (Nodes) .......... 2.02
********************** RAINFALL DATA ******~****************
7ypeII 24hr.... Pre.10
Synthetic Cumulative Depth ......... 3.01
TypeII 24hr.... Pre100
Synthetic Cumulative Depth ......... 3.03
********************** TC CALCULATIONS *********************
TC (PRE)........ Tc Calcs ........................... 4.01
********************** CN CALCULATIONS **********s**********
POND #1 (PRE)... Runoff CN-Area ..................... 5.01
******************** RUNOFF HYDROGRAPHS ********************
PRE-DEV......... Pre.10
SCS Unit Hyd. Summary .............. 6.01
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

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Table of Contents
Table of Contents (continued)
ii
PRE-DEV......... Pre100
SCS Unit Hyd. Summary .............. 6.02
S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

Type.... Master Network Summary Page 1.01
Name.... Watershed
Fite.... F:\PROJECTS\424-04\CALCS\POND1-PRE.PPW
MASTER DESIGN STORM SUMMARY
Default Network Design Storm File, ID HP.RNQ HP Storms
Total
Depth Rainfall
Return Event in Type RNF File RNF ID
Pre.10 5.1000 Synthetic Curve SCSTYPES TypeII 24hr
Pre100 7.5000 Synthetic Curve SCSTYPES TypeII 24hr
MASTER NETWORK SUMMARY
SCS Uhit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(True= HYG Truncation: Btank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
Storage
Node ID
------------- Type
---- ---- Event
------ ac-ft Trun
---------- --
*OUTLET JCT 10 1.648
*OUTLET JCT 100 3.052
PRE-DEV AREA 10 1.648
PRE-DEV AREA 100 3.052
Max
Qpeak Qpeak Max WSEL Pond
hrs cfs #t ac-ft
--------- -------- -------- ---------
12.0240 24.42
12.0240 45.41
12.0240 24.42
12.0240 45.41
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765} Compute Time: 10:23:00 Date: 01/26!2007

Type.... Executive Summary (Nodes) Page 2.01
Name.... Watershed Event: 10 yr
Fite.... F:\PROJECTS\424-04\CALCS\POND1-PRE.PPW
Storm... TypelI 24hr Tag: Pre.10
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = HP.RNQ HP Storms
Storm Tag Name = Pre.10
Description: 10-Year, 24-Hour
Data Type, File, ID Synthetic Storm SCSTYPES.RNF TypelI 24hr
Storm Frequency = 10 yr
Total Rainfall Depth= 5.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
HYG Vot Qpeak Qpeak Max WSEL
Node ID Type ac-ft Trun. hrs cfs ft
----------------- ---- ---------- -- --------- -------- ---------
Outfatt OUTLET JCT 1.648 12.0240 24.42
PRE-DEV AREA 1.64$ 12.0240 24.42
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

Type.... Executive Summary (Nodes) Page 2.02
Name.... Watershed Event: 100 yr
File.... F:\PROJECTS\424-04\CALCS\POND1-PRE.PPW
Storm... TypeII 24hr Tag: Pre100
NETWORK 5UMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
' DEFAULT Design Storm File,ID = HP.RNQ HP Storms
Storm Tag Name = Pre100
Description: 100-Year, 24-Hour
-
-
--
----------
----------------
----------------------------------
---
Data Type, Fite, ID = Synthetic Storm -
SCSTYPES.RNF TypeII 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 7.5000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs En d= 24.0000 hrs
HYG Vol Qpeak Qpeak Max WSEL
ac_ft
Trunk
hrs
Node
ID
Type cfs
ft
--
-
---------
---
-
Outfall OUTLET JCT 3.052 --
---
12.0240 --- ---
----
--
45.41
PRE-DEV AREA 3.052 12.0240 45.41

t
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S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007
1

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Type.... Synthetic Cumulative Depth Page 3.01
Name.... TypeII 24hr Tag: Pre.10 Event: 10 yr
Fite.... C:\HAESTAD\PPKW\RAINFALL\SCSTY PES.RNF
Title... 10-Year, 24-Ho ur
Storm... TypeII 24hr Tag: Pre.10
CUMULATIVE RAINF ALL DEPT HS (in)
Time ~ Output Time incr ement = .1000 hrs
hrs ~ Ti me on left represents time for first value in each row.
.0000 ~ .0000 .0052 .0103 .0156 .0208
.5000 ~ .0262 .0315 .0370 .0424 .0480
1.0000 ~ .0536 .0592 .0649 .0706 .0764
1.5000 ~ .0823 .0881 .094.1 .1001 .1061
2.0000 ~ .1122 .1184 .1245 .1308 .1371
2.5000 ~ .1435 .1498 .1563 .1628 .1694
3.0000 ~ .1760 .1826 .1893 .1961 .2029
3.5000 ( .2098 .2166 .2236 .2306 .2377
4.0000 r .2448 .2520 .2593 .2667 .2742
4.5000 ~ .2818 .2895 .2973 .3052 .3132
5.0000 ~ .3213 .3295 .3378 .3462 .3548
5.5000 ( .3634 .3721 .3809 .3898 .3989
6.0000 ~ .4080 .4172 .4266 .4360 .4455
6.5000 ~ .4552 .4649 .4748 .4847 .4948
7.0000 ~ .5049 .5152 .5255 .5360 .5465
7.5000 ~ .557Z .5679 .5788 .589$ .6008
8.0000 ~ .6120 .6235 .6355 .6480 .6610
8.5000 ~ .6745 .6885 .7030 .7181 .7336
9.0000 ~ .7497 .7660 .7823 .7987 .8150
9.5000 ~ .8313 .8480 .8656 .8839 .9031
10.0000 ~ .9231 .9441 .9663 .9898 1.0145
10.5000 ~ 1.0404 1.0679 1.0975 1.1291 1.1628
11.0000 ( 1.1985 1.2377 1.2817 1.3307 1.3845
11.5000 ~ 1.4433 1.5649 1.8072 2.1970 2.8961
12.0000 ~ 3.3813 3.4780 3.5631 3.6365 3.6983
12.5000 ~ 3.7485 3.7915 3.8319 3.8697 3.9048
13.0000 ~ 3.9372 3.9676 3.9966 4.0241 4.0502
13.5000 ~ 4.0749 4.0984 4.1208 4.1422 4.1626
14.0000 ~ 4.1820 4.2007 4.2190 4.2370 4.2546
14.5000 ~ 4.2719 4.2888 4.3054 4.3215 4.3374
15.0000 ~ 4.3529 4.3680 4.3827 4.3972 4.4112
15.5000 ( 4.4249 4.4382 4.4512 4.4638 4.4761
16.0000 ) 4.4880 4.4997 4.5112 4.5226 4.5339
16.5000 ~ 4.5451 4.5561 4.5670 4.5778 4.5884
17.0000 ~ 4.5989 4.6093 4.6196 4.6297 4.6397
17.5000 ~ 4.6496 4.6594 4.6690 4.6785 4.6879
18.0000 ( 4.6971 4.7062 4.7152 4.7241 4.7328
18.5000 ~ 4.7414 4.7499 4.7582 4.7665 4.7746
19.0000 ~ 4.7825 4.7904 4.7981 4.8057 4.8131
19.5000 ( 4.8205 4.8277 4.8347 4.8417 4.8485
20.0000 ~ 4.8552 4.8618 4.8684 4.8750 4.8815
20.5000 ~ 4.8880 4.8945 4.9010 4.9074 4.9139
21.0000 ~ 4.9202 4.9266 4.9329 4.9392 4.9455
21.5000 ~ 4.9518 4.9580 4.9642 4.9704 4.9766
22.0000 ~ 4.9827 4.9888 4.9949 5.0010 5.0070
' S/N: 621605B06A8F
PondPack Ver. 7.5 (765)
CPT Engineering & Surveying, Inc.
Compute Time: 10:23:00 Date: 01/26/2007
1

Type.... Synthetic Cumulative Depth Page 3.02
Name.... TypeII 24hr Tag: Pre.10 Event: 10 yr
Fite.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Title...
Storm... 10-Year, 24-Hour
TypeII 24hr Tag: Pre.10
CUMULATIVE RAINFALL DEPT HS (in)
' Time
hrs ~ Output Time increment =
~ Time on left represents time for .1000 hrs
first value
in each row.
22.5000 ~ 5.0130 5.0190 5.0249 5.0308 5.0368
23.0000 ~ 5.0426 5.0485 5.0543 5.0601 5.0659
23.5000 ~ 5.0716 5.0774 5.0831 5.0887 5.0944
24.0000 ~ 5.1000

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f
S/N: 62160S606ASF CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007
1

Type.... Synthetic Cumulative Depth
Name.... TypeII 24hr Tag: Pre100 Page 3.03
Event: 100 yr
Fite..., C:\HAE STAD\PPKW\RAI NFALL\SCSTYPES.RNF
Title... 100-Ye
Storm... TypeTI ar, 24-Hour
24hr Tag:
Pre100
CUMUL ATIVE RAINFALL DEPTHS (in )
Time ~
hrs ~ Outpu
Time on left t Time incr
represents ement = .1000
time for first
- hrs
value in
__-
--
each row.
-_
--_--
_--- -I----
.0000 ~
.5000 ~
1.0000 ~
1.5000 ~
2.0000 ~
2.5000 ~
3.0000 ~
3.5000 ~
4.0000 ~
4.5000 ~
5.0000 ~
5.5000 ~
6.0000 ~
6.5000 ~
7.0000 ~
7.5000 ~
8.0000 ~
8.5000 ~ ---.0000__--_
.0385
.078$
.1210
.1650
.2110
.2588
.3085
.3600
.4144
.4725
.5344
.6000
.6694
.7425
.8194
.9000
.9919 _--0076-_--
.0464
.0871
.1296
.1741
.2204
.2686
.3186
.3706
.4257
.4846
.5472
.6136
.6837
.7576
.8352
.9169
1.0125 ---.0152 __-_
.0544
.0954
.1384
.1832
.2299
.2784
.3289
.3813
.4372
.4968
.5602
.6273
.6982
.7728
.8512
.9345
1.0339 0229
.0624
.1039
.1472
.1924
.2394
.2884
.3392
.3922
.4488
.5092
.5733
.6412
.7128
.7882
.8673
.9529
1.0560 0306
.0706
.1124
.1561
.2016
.2491
.2984
.3496
.4032
.4606
.5217
.5866
.6552
.7276
.8037
.8836
.9720
1.0789
9.0000 ~ 1.1025 1.1265 1.1505 1.1745 1.1985
9.5000 ~
10.0000 ~ 1.2225
1.3575 1.2471
1.3884 1.2729
1.4211 1.2999
1.4556 1.3281
1.4919
10.5000 ~
11.0000 ~
11.5000 ~
12.0000 ~ 1.5300
1.7625
2.1225
4.9725 1.5705
1.8201
2.3013
5.1147 1.6140
1.8849
2.6577
5.2398 1.6605
1.9569
3.2309
5.3478 1.7100
2.0361
4.2590
5.4387
12.5000 ~
13.0000 ~
13.5000 ~
14.0000 ~
14.5000 ~ 5.5125
5.7900
5.9925
6.1500
6.2822 5.5758
5.8347
6.0270
6.1775
6.3071 5.6352
5.8773
6.0600
6.2045
6.3314 5.6907
5.9178
6.0915
6.2309
6.3552 5.7423
5.9562
6.1215
6,2568
6.37$5
15.0000 ~
15.5000 ~
16.0000 ~ 6.4013
6.5072
6.6000 6.4235
6.5268
6.6172 6.4452
6.5459
6.6341 6.4664
6.5645
6.6509 6.4871
6.5825
6.6675
16.5000 ~
17.0000 ~
17.5000 ~ 6.6839
6.7631
6.$377 6.7001
6.7784
6.8520 6.7162
6.7935
6.8662 6.7320
6.8084
6.8801 6.7477
6.8231
6.8939
18.0000 ~ 6.9075 6.9209 6.9341 6.9472 6.9600
18.5000 ~
19.0000 ~ 6.9727
7.0331 6.9851
7.0447 6.9974
7.0560 7.0095
7.0672 7.0214
7.0781
19.5000 ~ 7.0889 7.0995 7.1099 7.1201 7.1302
20.0000 ~
20.5000 ~
21.0000 ( 7.1400
7.1883
7.2356 7.1498
7.1978
7.2450 7.1594
7.2074
7.2543 7.1691
7.2168
7.2636 7.1787
7.2263
7.2728
21.5000 ~ 7.2821 7.2912 7.3004 7.3094 7.3185
22.0000 ~ 7.3275 7.3365 7.3454 7.3544 7.3632

S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007
1

Type.... Synthetic Cumulative Depth
Name.... TypeII 24hr Tag: Pre100 Page 3.04
Event: 100 yr
Fite.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Titte... 100-Year, 24-Hour
Storm... TypeII 24hr Tag: Pre100
CUMULATIVE RAINFALL DEPT HS (in)
Time ~ Output Time increment =
hrs ~ Time on left represents time for .1000 hrs
first value
in each row.
22.5000 ( 7.3721 7.3808 7.3896
23.0000 ~ 7.4156 7'.4243 7.4328
23.5000 ~ 7.4583 7.4667 7.4751 7.3983
7.4414
7.4834 7.4070
7.4498
7.4918
24.0000 ~ 7.5000

1
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S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

Type.... Tc Calcs Page 4.01
Name.... TC (PRE)
Fite.... F:\PR0IECTS\424-04\CALCS\POND1-PRE.PPW
Title... Tc (Pre)
TIME OF CONCENTRATION CALCULATOR
.........................................................................
Tc (Pre)
Segment #1: Tc: TR-55 Sheet
Description: Sheet Ftow
Mannings n .1500
Hydraulic Length 167.00 ft
' 2yr, 24hr P 3.5000 in
Slope .030000 ft/ft
Avg.Vetocity .23 ft/sec
Segment #1 Time: .2001 hrs

Segment #2: 7c: TR-55 Shallow
Description: Shallow Conc Ftow
( Hydraulic Length 517.00 ft
Slope .068000 ft/ft
Unpaved
Avg.Vetocity 4.21 ft/sec
Segment #2 Time: .0341 hrs

2342
hrs
Total
Tc:
i _
_
_~_
_

n
u

1
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: O1/26J2007

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Type.... Tc Calcs Page 4.02
Name.... TC (PRE)
File.... F:\PROJECTS\424-04\CALCS\POND1-PRE.PPW
Title... Tc (Pre)
Tc Equations used.,.
___= SCS TR-55 Sheet Flow ______________________________________________
Tc = (.007 ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n =Mannings n
Lf = Ftow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, ft/ft
___= SC5 TR-55 Shallow Concentrated Flow _______________________________
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V =Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf =Flow length, ft
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

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Type.... Runoff CN-Area Page 5.01
Name.... POND #1 (PRE)
File.... F:\PROJECTS\424-04\CAICS\POND1- PRE.PPW
Title... Pond #1: (Pre-developed)
RUNOFF CURVE NUMBER DATA
Pond #1: (Pre-developed)
----------------------------------
------
---------
-------------------------
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN
Woods good hydrologic condition 70 4.960 70.00
Grass, good hydrologic condition 74 2.930 74.00
Impervious Areas 98 .490 98.00
COMPOSITE AREA & WEIGHTED CN ---> 8.380 73.04 (73)
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

Type.... SCS Unit Hyd. Summary Page 6.01
Name.... PRE-DEV Tag: Pre.10 Event: 10 yr
Fite.... F:\PROJECTS\424-04\CALCS\POND1-PRE.PPW
Storm... TypeII 24hr Tag: Pre.10
SCS UNIT HYDROGRAPH METHOD
STORM EVENT: 10 year storm
Duration = 24.0000 hrs Rain Depth = 5.1000 in
Rain Dir = C:\HAESTAD\PPKW\RAINFALL\
Rain Fite -ID = SCSTYPES.RNF - TypeII 24hr
Unit Hyd Type = Default Curvilinear
HYG Dir F:\PROJECTS\424-04\CALCS\
HYG File - ID = P1-PRE.HYG - PRE-DEV Pre.10
Tc = .2342 hrs
Drainage Area = 8.380 acres Runoff CN= 73

Computational Time Increment .03123 hrs
Computed Peak Time 12.0243 hrs
Computed Peak Ftow = 24.44 cfs
Time Increment for HYG Fite = .0167 hrs
Peak Time, Interpolated Output = 12.0239 hrs
Peak Ftow, Interpolated Output = 24.42 cfs
DRAINAGE AREA

-------------------
ID:Pond #1 (Pre)
CN 73
Area = 8.380 acres
5 = 3.6986 in
0.25 = .7397 in
Cumulative Runoff
-------------------
2.3591 in
1.647 ac-ft
HYG Volume... 1.648 ac-ft (area under HYG curve)
***** UNIT HYDROGRAPH PARAMETERS *****
Time Concentration, Tc = .23424 hrs (ID: Tc (Pre))
Computational Incr, Tm = .03123 hrs = 0.20000 Tp
Unit Hyd. Shape Factor = 483.432 (37.46% under rising limb)
K 483.43/645.333, K = .7491 (also, K = 2/(1+(Tr/Tp))
Receding/Rising, Tr/Tp = 1.6698 (solved from K = .7491)
Unit peak, qp = 40.53 cfs
Unit peak time Tp = .15616 hrs
Unit receding limb, Tr = .62464 hrs
Total unit time, Tb = .78080 hrs

1
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

_ Type.... SCS Unit Hyd. Summary Page 6.02
Name.... PRE-DEV Tag: Pre100 Event: 100 yr
Fite.... F:\PROJECTS\424-04\CALCS\POND1-PRE.PPW
Storm... TypelI 24hr Tag: Pre100
SCS UNIT HYDROGRAPH METHOD
Mm STORM EVENT: 100 year storm
Duration = 24.0000 hrs Rain Depth = 7.5000 in
Rain Dir = C:\HAESTAD\PPKW\RAINFALL\
Rain Fite -ID = SCSTYPES.RNF - TypeII 24hr
r Unit Hyd Type = Default Curvilinear
HYG Dir = F:\PROJECTS\424-04\CALCS\
HYG Fite - ID = P1-PRE.HYG - PRE-DEV Pre100
~ Tc = .2342 hrs
Drainage Area = 8.380 acres Runoff CN= 73
Computational Time Increment - .03123 hrs
Computed Peak Time = 12.0243 hrs
Computed Peak Ftow = 45.44 cfs
'r Time Increment for HYG File = .0167 hrs
Peak Time, Interpolated Output = 12.0239 hrs
Peak Ftow, Interpolated Output = 45.41 cfs
•
_ DRAINAGE AREA
,.~ ID:Pond #1 (Pre)
CN = 73
- Area = 8.380 acres
S = 3.6986 in
~ 0.25 .7397 in
`- Cumulative Runoff
-------------------
ra
4.3696 in
3.051 ac-fit
.~ HYG Volume... 3.052 ac-ft (area under HYG curve)
~- ***** UNIT HYDROGRAPH PARAMETERS *****
+~ Time Concentration, Tc = .23424 hrs (ID: Tc (Pre))
Computational Incr, Tm = .03123 hrs = O.Z0000 Tp
~ Unit Hyd. Shape Factor = 483.432 (37.46% under rising limb)
K = 483.43/645.333, K = .7491 (also, K = Z/(1+(Tr/Tp))
_ Receding/Rising, Tr/Tp = 1.6698 (solved from K = .7491)
.. Unit peak, qp = 40.53 cfs
Unit peak time Tp = .15616 hrs
Unit receding limb, Tr = .62464 hrs
Total unit time, Tb = .78080 hrs
~.
w
5/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:23:00 Date: 01/26/2007

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WET DETENTION POND DESIGN
WET DETENTION POND #1
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WET DETENTION POND #1
WET DETENTION POND
DESIGN ROUTING

Table of Contents
Table of Contents
1
********************** MASTER SUMMARY **********ss*:********
Watershed....... Master Network Summary ............. 1.01
*************** NETWORK SUMMARIES (DETAILED) ***************
Watershed....... Dev.10
Executive Summary (Nodes) .......... 2.01
Watershed....... Dev100
Executive Summary (Nodes) .......... 2.02
****************** DESIGN STORMS SUMMARY *******************
HP Storms....... Design Storms ...................... 3.01
********************** RAINFALL DATA ********:**************
TypelI 24hr.... Dev.10
Synthetic Cumulative Depth ......... 4.01
TypeII 24hr.... Dev100
Synthetic Cumulative Depth ......... 4.03
********************** CN CALCULATIONS ****s****************
POND #1 (POST).. Runoff CN-Area ..................... 5.01
***:******************* POND VOLUMES ***********************
POND #1......... Vol: Elev-Area ..................... 6.01
S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Table of Contents
Table of Contents (continued)
ii
******************** OUTLET STRUCTURES *********************
OUTLET DEVICE... Outlet Input Data .................. 7.01
*********************** POND ROUTING *********:*************
POND #1......... Pond E-V-Q Table ................... 8.01
POND #1 OUT Dev.10
Pond Routing Summary ............... 8.02
POND #1 OUT Dev100
Pond Routing Summary ............... 8.03
S/N: 621605B06A8F CPT Engineering & Surveying. Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Master Network Summary Page 1.01
Name.... Watershed
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
MASTER DESIGN STORM SUMMARY
Default Network Design Storm File, ID HP.RNQ HP Storms
Total
Depth Rainfall
Return Event in Type RNF File RNF ID
------------ ------ ---------------- -------- ----------------
Dev.10 5.1000 Synthetic Curve SCSTYPES TypeII 24hr
Dev100 7.5000 Synthetic Curve SCSTYPES TypeII 24hr
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
Storage
Node ID--------- Type Event ---ac=ft-- Trun
*OUTLET JCT 10 2.248
*OUTLET JCT 100 4.045
POND #1 IN POND 10 2.706
POND #1 IN POND 100 4.521
POND #1 OUT POND 10 2.248
1.216
POND #1 OUT POND 100 4.045
1.667
POST-DEVELOPED AREA 10 2.706
POST-DEVELOPED AREA 100 4.521
Max
Qpeak Qpeak Max WSEL Pond
---hrs--- --cfs--- ---ft--- ---ac_ft-
12.0741 20.13
12.0240 57.02
11.9238 50..31
11.923$ 82.11
12.0741 20.13 850.69
12.0240 57.02 851.85
11.9238 50.31
11.9238 82.11
S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

Type.... Executive Summary (Nodes)
Name.... Watershed Page 2.01
Event: 10 yr
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Storm.,. TypeI2 24hr Tag: Dev.10
NETWORK SUMMARY
-- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
' DEFAULT Design Storm File,ID = HP.RNQ HP Storms
Storm Tag Name = Dev.10
Description: 10-Year, 24-Hour
-----------
-------------
----------------

' ----------------------------
Data Type, File, ID = Synthetic Storm
Storm Frequency = 10 yr SCSTYPES.RNF TypeII 24hr
Total Rainfall Depth= 5.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step=
.1000 hrs End= 24.0000 hrs
HYG Vol Qpeak Qpeak Max WSEL
-hrs---
Trun_
ac_ft
Type
ID
Node --cfs--- ---ft----
--
---
---------
-
-
Outfalt OUTLET JCT 2.248 -
12.0741 20.13

' POND #1 IN POND 2.706
POND #1 OUT POND 2.248 11.9238
12.0741 50.31
20.13 850.69
POST-DEVELOPED AREA 2.706 11.9238 50.31
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' S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 bate: 04/16/2007

Type.... Executive Summary (Nodes) Page 2.02
Name.... Watershed Event: 100 yr
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Storm... TypeII 24hr Tag: Dev100
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
' DEFAULT Design Storm File,ID = HP.RNQ HP Storms
' Storm Tag Name = Dev100
Description: 100-Year, 24-Hour
-----------
-------------
----------------

' ----------------------------
Data Type, File, ID = Synthetic Storm
Storm Frequency = 100 yr SCSTYPES.RNF TypeII 24hr
Total Rainfall Depth= 7.5000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs En d= 24.0000 hrs
HYG Vol Qpeak Qpeak Max WSEL
hrs---
Truny
ac_ft
Type
ID
Node --cfs--- ---ft----
--
---
---------
-
-
Outfall OUTLET JCT 4.045 --
12.0240 57.02
POND #1 IN POND 4.521 11.9238 82.11
POND #1 OUT POND 4.045 12.0240 57.02 851.85
POST-DEVELOPED AREA 4.521 11.9238 82.11
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' S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Design Storms Page 3.01
Name.... HP Storms
File.... C:\HAESTAD\PPKW\RAINFALL\HP.RNQ
Title... Alexandria Park Apartments
NC Hwy 68 & Whites Mill Road
Blue Ridge Companies, Inc.
Pond #1 (Post-developed)
DESIGN STORMS SUMMARY
Design Storm File,ID = HP.RNQ HP Storms
Storm Tag Name = Dev.10
Description_-10_Year_-24_Hour-----------------------------------------
Data Type, File, ID = Synthetic Storm SCSTYPES.RNF TypeII 24hr
Storm Frequency = 10 yr
Total Rainfall Depth= 5.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
Storm Tag Name = Dev100
Descriptian~-100=Year_-24_Hour----------------------------------------
Data Type, File, ID = Synthetic Storm SCSTYPES.RNF TypeIl 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 7.5000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007
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Type.... Synthetic Cumulative Depth Page 4.01
Name.... TypeII 24hr Tag: Dev.10 Event: 10 yr
File.... C:\HAESTAD\PPKW\RAI NFALL\SCSTY PES.RNF
Title... 10~-Year, 24-Hour
Storm... TypeII 24hr Tag: Dev.10
CUMUL ATIVE RAINF ALL DEPTHS (in )
Time ~ Outpu t Time incr ement = .1000 hrs
hrs ~ Ti me on left represents time for first value
-
---- in each row.
-------------
---------i------
.0000 -----------
.0000 -----------
.0052 --------------
.0103 -
-
.0156 .0208
.5000 ~ .0262 .0315 .0370 .0424 .0480
1.0000 ~ .0536 .0592 .0649 .0706 .0764
1.5000 ~ .0823 .0881 .0941 .1001 .1061
2.0000 ~ .1122 .1184 .1245 .1308 .1371
2.5000 ~ .1435 .149$ .1563 .1628 .1694
3.0000 ~ .1760 .1826 .1893 .1961 .2029
3.5000 ~ .2098 .2166 .2236 .2306 .2377
4.0000 ~ .2448 .2520 .2593 .2667 .2742
4.5000 ~ .2818 .2895 .2973 .3052 .3132
5.0000 ~ .3213 .3295 .3378 .3462 .3548
5.5000 ~ .3634 .3721 .3809 .3898 .3989
6.0000 ~ .4080 .4172 .4266 .4360 .4455
6.5000 ~ .4552 .4649 .474$ .4847 .4948
7.0000 ~ .5049 .5152 .5255 .5360 .5465
7.5000 ~ .5572 .5679 .5788 .5898 .6008
8.0000 ~ .6120 .6235 .6355 .6480 .6610
8.5000 ~ .6745 .6885 .7030 .7181 .7336
9.0000 ~ .7497 .7660 .7823 .7987 .8150
9.5000 ~ .8313 .8480 .8656 .8839 .9031
10.0000 ~ .9231 .9441 .9663 .9898 1.0145
10.5000 ~ 1.0404 1.0679 1.0975 1.1291 1.1628
11.0000 ~ 1.1985 1.2377 _1.2817 1.3307 1.3845
11.5000 ~ 1.4433 1.5649 1.8072 2.1970 2.8961
12.0000 ~ 3.3813 3.4780 3.5631 3.6365 3.6983
12.5000 f 3.7485 3.7915 3.8319 3.8697 3.9048
13.0000 ~ 3.9372 3.9676 3.9966 4.0241 4.0502
13.5000 ~ 4.0749 4.0984 4.1208 4.1422 4.1626
14.0000 ~ 4.1820 4.2007 4.2190 4.2370 4.2546
14.5000 E 4.2719 4.2888 4.3054 4.3215 4.3374
15.0000 ( 4.3529 4.3680 4.3827 4.3972 4.4112
15.5000 ~ 4.4249 4.4382 4.4512 4.4638 4.4761
16.0000 ( 4.4880 4.4997 4.5112 4.5226 4.5339
16.5000 ~ 4.5451 4.5561 4.5670 4.5778 4.5884
17.0000 ~ 4.5989 4.6093 4.6196 4.6297 4.6397
17.5000 ~ 4.6496 4.6594 4.6690 4.6785 4.6879
18.0000 ~ 4.6971 4.7062 4.7152 4.7241 4.7328
18.5000 ~ 4.7414 4.7499 4.7582 4.7665 4.7746
19.0000 ~ 4.7825 4.7904 4.7981 4.8057 4.8131
19.5000 ~ 4.8205 4.8277 4.8347 4.8417 4.8485
20.0000 E 4.8552 4.8618 4.8684 4.8750 4.8815
20.5000 ~ 4.8880 4.8945 4.9010 4.9074 4.9139
21.0000 ~ 4.9202 4.9266 4.9329 4.9392 4.9455
21.5000 ~ 4.9518 4.9580 4.9642 4.9704 4.9766
22.0000 ~ 4.9827 4.9888 4.9949 5.0010 5.0070
5/N: 621605B06A8F
PondPack Ver. 7.5 (765)
CPT Engineering & Surveying, Inc.
Compute Time: 16:02:09 Date: 04/16/2007
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Type.... Synthetic Cumulative Depth Page 4.02
Name.... TypelI 24hr Tag: Dev.10 Event: 10 yr
Fite.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Title... 10-Year, 24-Hour
Storm... TypeII 24hr Tag: Dev.10
CUMULATIVE RAINFALL DEPTHS (in)
Time ~ Output Time increment = .1000 hrs
hrs ~ Time on left represents time for first value in each row.
22.5000 ~ 5.0130 5.0190 5.0249 5.0308 5.0368
23.0000 ~ 5.0426 5.0485 5.0543 5.0601 5.0659
23.5000 ( 5.0716 5.0774 5.0831 5.0887 5.0944
24.0000 { 5.1000
5/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Synthetic Cumulative Depth Page 4.03
Name.... TypeiI 24hr Tag: Dev100 Event: 100 yr
File.... C:\HAE STAD\PPKW\RAI NFALL\SCSTY PES.RNF
Title... 10!0-Ye ar, 24-Hour
Storm... TypeII 24hr Tag: Dev100
CUMULATIVE RAINF ALL DEPTHS (in)
Time { Output Time incr ement = .1000 hrs
hrs { Time on left represents time for first value in each row.
.0000 { .0000 .0076 .0152 .0229 .0306
.5000 ( .0385 .0464 .0544 .0624 .0706
1.0000 { .0788 .0871 .0954 .1039 .1124
1.5000 { .1210 .1296 .1384 .1472 .1561
2.0000 { .1650 .1741 .1832 .1924 .2016
2.5000 ( .2110 .2204 .2299 .2394 .2491
3.0000 { .2588 .2686 .2784 .2884 .2984
3.5000 { .3085 .3186 .3289 .3392 .3496
4.0000 { .3600 .3706 .3813 .3922 .4032
4.5000 { .4144 .4257 .4372 .4488 .4606
5.0000 { .4725 .4846 .4968 .5092 .5217
5.5000 { .5344 .5472 .5602 .5733 .5866
6.0000 { .6000 .6136 .6273 .6412 .6552
6.5000 ( .6694 .6837 .6982 .7128 .7276
7.0000 { .7425 .7576 .7728 .7882 .8037
7.5000 { .8194 .8352 .8512 .8673 .8836
8.0000 { .9000 .9169 .9345 .9529 .9724
8.5000 { .9919 1.0125 1.0339 1.0560 1.0789
9.0000 { 1.1025 1.1265 1.1505 1.1745 1.1985
9.5000 { 1.2225 1.2471 1.2729 1.2999 1.3281
10.0000 { 1.3575 1.3884 1.4211 1.4556 1.4919
10.5000 { 1.5300 1.5705 1.6140 1.6605 1.7100
11.0000 { 1.7625 1.8201 1.8849 1.9569 2.0361
11.5000 { 2.1225 2.3013 2.6577 3.2309 4.2590
12.0000 { 4.9725 5.1147 5.2398 5.3478 5.4387
12.5000 { 5.5125 5.5758 5.6352 5.6907 5.7423
13.0000 { 5.7900 5.8347 5.8773 5.9178 5.9562
13.5000 { 5.9925 6.0270 6.0600 6.0915 6.1215
14.0000 { 6.1500 6.1775 6.2045 6.2309 6.2568
14.5000 { 6.2822 6.3071 6.3314 6.3552 6.3785
15.0000 { 6.4013 6.4235 6.4452 6.4664 6.4871
15.5000 { 6.5072 6.5268 6.5459 6.5645 6.5825
16.0000 { 6.6000 6.6172 6.6341 6.6509 6.6675
16.5000 { 6.6839 6.7001 6.7162 6.7320 6.7477
17.0000 { 6.7631 6.7784 6.7935 6.8084 6.8231
17.5000 { 6.8377 6.8520 6.8662 6.8801 6.8939
18.0000 { 6.9075 6.9209 6.9341 6.9472 6.9600
18.5000 { 6.9727 6.9851 6.9974 7.0095 7.0214
19.0000 { 7.0331 7.0447 7.0560 7.0672 7.0781
19.5000 { 7.08$9 7.0995 7.1099 7.1201 7.1302
20.0000 { 7.1400 7.1498 7.1594 7.1691 7.1787
20.5000 { 7.1883 7.1978 7.2074 7.2168 7.2263
21.0000 ( 7.2356 7.2450 7.2543 7.2636 7.2728
21.5000 { 7.2821 7.2912 7.3004 7.3094 7.3185
22.0000 { 7.3275 7.3365 7.3454 7.3544 7.3632
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Synthetic Cumulative Depth Page 4.04
Name.... TypeII 24hr Tag: Dev100 Event: 100 yr
File.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Title... 100-Year, 24-Hour
Storm... TypeII 24hr Tag: Dev100
CUMULATIVE RAINFALL DEPTHS (in)
Time ~ Output Time increment = .1000 hrs
hrs ~ Time on left represents time for first value in each row.
22.5000 ~ 7.3721 7.3808 7.3896 7.3983 7.4070
23.0000 ~ 7.4156 7.4243 7.4328 7.4414 7.4498
23.5000 ~ 7.4583 7.4667 7.4751 7.4834 7.4918
24.0000 ~ 7.5000
5/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 1765) Compute Time: 16:02:09 Date: 04/16/2007
1

Type.... Runoff CN-Area Page 5.01
Name.... POND #1 (POST)
Fite.... F:\PROJECTS\424-04\CALCS\POND1- POST.PPW
Title... Pond #1 (Post-developed)
RUNOFF CURVE NUMBER DATA
Pond #1 (Post-developed)
----------------------------------------
----------
------------------------
Impervious
Area Adjustment Adjusted
Soil/Surfac:e Description CN acres %C %UC CN
Impervious Areas 98 6.050 98.00
Open space, good condition 61 3.610 61.00
COMPOSITE AREA & WEIGHTED CN ---> 9.660 84.17 (84)
S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Vol: Elev-Area Page 6.01
Name.... POND #1
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Title... Pond #1
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft) (sq.in) (acres) (acres)
----------- (ac-ft)
---------- (ac-ft)
-------------
-----------
847.00 ----------------------
----- .2850 -----
.0000 .000 .000
848.00 ----- .3090 .8908 .297 .297
849.00 ----- .3330 .9628 .321 .618
850.00 ----- .3580 1.0363 .345 .963
852.00 ----- .4090 1.1497 .766 1.730
853.00 ----- .4360 1.2673 .422 2.152
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Areal + sq.rt.(Area1*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
5/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Outlet Input Data Page 7.01
Name.... OUTLET DEVICE
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Title... Outlet Structure
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 847.00 ft
Increment = .50 ft
Max. Elev.= 853.00 ft
OUTLET CONNECTIVITY
~***********~*s****~*~*****************~*~*~**
---> 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 ST ---> TW .000 853.000
TW SETUP, DS Channel
S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

Type.... Outlet Input Data
Name.... OUTLET DEVICE
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Title... Outlet Structure
OUTLET STRUCTURE INPUT DATA
Structure ID = ST
Structure Type = User Defined Table
------------------------------------
ELEV-FLOW RATING TABLE
Elev, ft Flow, cfs
--------- ---------
847.00 .00
847.50 .07
848.00 .10
848.50 .12
849.00 .15
849.50 3.35
850.00 9.18
850.50 16.73
851.00 25.66
851.50 36.22
852.00 66.37
852.50 102.07
853.00 142.56
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFACE 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
Page 7.02
51N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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Type.... Pond E-V-Q Table Page 8.01
Name.... POND #1
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
LEVEL POOL ROUTING DATA
HYG Dir = F:\PROJECTS\424-04\CALCS\
Inflow HYG file = P1-POST.HYG - POND #1 IN Dev.10
Outflow HYG file = P1-POST.HYG - POND #1 OUT Dev.10
Pond Node Data = POND #1
Pond Volume Data = POND #1
Pond Outlet Data = OUTLET DEVICE
No Infiltration
INITIAL CONDITIONS
Starting WS Elev = 847.00 ft
Starting Volume = .000 ac- ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0167 hrs
Elevation Outflow Storage Area Infilt. Q Total 25/t + 0
ft cfs ac_ft acres cfs cfs ---cfs--
----
-------
847.00 -------
--
.00 --
-
.000 ---- ---
.2850 ----
----
.00 ----
-----
.00 --
.00
847.50 .07 .145 .2969 .00 .07 210.86
848.00 .10 .297 .3090 .00 .10 430.37
848.50 .12 .454 .3209 .00 .12 658.57
849.00 .15 .618 .3330 .00 .15 895.47
849.50 3.35 .787 .3454 .00 3.35 1144.42
850.00 9.18 .963 .3580 .00 9.18 1405.06
850.50 16.73 1.145 .3704 .00 16.73 1676.49
851.00 25.66 1.334 .3831 .00 25.66 1958.38
851.50 36.22 1.528 .3959 .00 36.22 2251.14
852.00 66.37 1.730 .4090 .00 66.37 2572.89
852.50 102.07 1.938 .4224 .00 102.07 2909.77
853.00 142.56 2.152 .4360 .00 142.56 3261.22
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007
1

Type.... Pond Routing Summary
Name.... POND #1 OUT Tag: Dev.10
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Storm... TypeII 24hr Tag: Dev.10
LEVEL POOL ROUTING SUMMARY
HYG Dir = F:\PROJECTS\424-04\CALCS\
Inflow HYG file = P1-POST.HYG - POND #1 IN Dev.10
Outflow HYG file = P1-POST.HYG - POND #1 OUT Dev.10
Pond Node Data = POND #1
Pond Volume Data = POND #1
Pond Outlet Data = OUTLET DEVICE
No Infiltration
INITIAL CONDITIONS
-------g- --------
Startin WS Elev ----------------
= 847.00 ft
Starting Volume - .000 ac-ft
Starting tlutflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0167 hrs
INFLOW/OUTFLOW HYDROGRAPH SUMMARY
Peak Inflaw = 50.31 cfs at 11.9238 hrs
Peak Outflow = 20_13 -cfs at 12.0741 hrs
--------------------
--
-------------------
Peak Elevation = ---
850.69 ft
Peak-Storage_=___---- _--1_216 -ac_ft_----_-__!_-__--__
MA55 BALANCE (ac-ft)
-
------
------------------
-
+ Initial Vol = .000
+ HYG Vol IN 2.706
- Infiltration = .000
HYG Vol OUT 2.248
- Retained Vol = .458
Unrouted Vol = - 000 ac-ft (.003% of Inflow Volume)
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Event: 10 yr
t S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

Type.... Pond Routing Summary Page 8.03
Name.... POND #1 OUT Tag: Dev10O Event: 100 yr
File.... F:\PROJECTS\424-04\CALCS\POND1-POST.PPW
Storm... TypeII 24hr Tag: Dev100
LEVEL POOL ROUTING SUMMARY
HYG Dir = F:\PROJECTS\424-04\CALCS\
Inflow HYG file = P1-POST.HYG - POND #1 IN Dev100
Outflow HYG file = P1-POST.HYG - POND #1 OUT Dev100
Pond Node Data = POND #1
Pond Volume Data = POND #1
Pond Outlet Data = OUTLET DEVICE
No Infiltration
INITIAL CONDITIONS
Starting WS Elev 847.00 ft
Starting Volume = .000 ac-ft
Starting Outflow = .00 cfs
Starting ]:nfiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0167 hrs

INFLOW/OUTFLOW HYDROGRAPH SUMMARY

Peak Inflow = 82.11 cfs at 11.9238 hrs
Peak Outflow = 57.02 cfs at
------------- 12.0240 hrs
------------
------------------
Peak Elevation ----------
= 851.85 ft
Peak_Storage_=____ ______1_667_ac_ft____'_ ____________
MASS BALANCE (ac-f t)
-----
------------------
+ Initial Vol = ---
.000
+ HYG Vol IN = 4.521
- Infiltration = .000
- HYG Vol OUT = 4.045
- Retained Vol = .476
r Unrouted Vol = - 000 ac-ft (.008% of Inflow Volume)
r~

1
r S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

Appendix A
Index of Starting Page Numbers for ID Names
----- H -----
HP Storms... 3.01
----- 0 -----
OUTLET DEVICE... 7.01
----- P --~---
POND #1... 6.01, 8.01, 8.02, 8.03
POND #1 (POST)... 5.01, 4.01, 4.03
----- W --~---
Watershed... 1.01, 2.01, 2.OZ

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S/N: 6Z1605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:02:09 Date: 04/16/2007

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WET DETENTION POND DESIGN
WET DETENTION POND #1
POND VOLUMES
PERMANENT WATER QUALITY SURFACE AREA
TEMPORARY WATER QUALITY STORAGE PROVIDED

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1
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WET DETENTION POND DESIGN
WET DETENTION POND #Z
PRE-DEVELOPMENT
HYDROLOGIC ANALYSIS
1

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Table of Contents
Table of Contents
1
********************** MASTER SUMMARY **********************
Watershed....... Master Network Summary ............. 1.01
*************** NETWORK SUMMARIES (DETAILED) ***************
Watershed....... Pre.10
Executive Summary (Nodes) .......... 2.01
Watershed....... Pre100
Executive Summary (Nodes) .......... 2.02
********************** RAINFALL DATA ****************~~*****
TypeII 24hr.... Pre.10
Synthetic Cumulative Depth ......... 3.01
TypeII 24hr.... Pre100
Synthetic Cumulative Depth ......... 3.03
*********s************ TC CALCULATIONS *********************
TC (PRE)........ Tc Calcs ........................... 4.01
********************** CN CALCULATIONS *********************
POND #2 (PRE)... Runoff CN-Area ..................... 5.01
******************** RUNOFF HYDROGRAPHS ********************
PRE-DEV......... Pre.10
SCS Unit Hyd. Summary .............. 6.01
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007

Table of Contents ~~
Table of Contents (continued)
PRE-DEV......... Pre100
SCS Unit Hyd. Summary .............. 6.02
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007

Type.... Executive Summary (Nodes) Page 2.01
Name.... Watershed Event: 10 yr
Fite.... F:\PROJECTS\424-04\CALCS\POND2-PRE.PPW
Storm... TypelI 24hr Tag: Pre.10
i NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank-None; L=Left; R=Rt; LR~Left & Rt)
`' DEFAULT Design Storm Fite,ID = HP.RNQ HP Storms
Storm Tag Name = Pre.10
--------
24_Hour-
10_Year_
Description+ ------------- ----------------
-
-
-
Data Type, Fite, ID = Synthetic Storm SCSTYPES.RNF TypeII 24hr
Storm Frequency = 10 yr
Total Rainfall Depth = 5.1000 in
Duration Multiplier = 1
Resulting Duration 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
HYG Vol Qpeak Qpeak Max WSEL
-Trun_--hrs---
ac_ft
Type
ID
Node --cfs--- ---ft----
-
---
---------
-
-
Outfall OUTLET JCT 2.501 12.1910 24.24
PRE-DEV AREA 2.501 12.1910 .24.24

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S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007

L Type....
Name.... Synthetic Cumulative Depth
TypeII 24hr Tag: Pre100 Page 3.04
Event: 100 yr
File.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Title...
Storm... 100-Year, 24-Hour
TypeII 24hr Tag: Pre100
CUMULATIVE RAINFALL DEPT HS (in)
Time
hrs ~ Output Time increment =
Time on left represents time for
i .1000 hrs
first value
in each row.
-------------
---
--
22.5000 ----
-
----------------------------
~ 7.3721 7.3808 7.3896 ------------
7.3983 -
7.4070
23.0000 ~ 7.4156 7.4243 7.4328 7.4414 7.4498
23.5000 ~ 7.4583 7.4667 7.4751 7.4834 7.4918
24.0000 I 7.5000

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S/N: 621605606A8F CPT Engineering & Surveying, Inc.
Por.dPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007
1

Type.... Runoff CN-Area Page 5.01
Name.... POND #2 (PRE)
File....
Title... F:\PROJECTS\424-04\CALCS\POND2-PRE.PPW
Pond #2: (Pre-developed)
RUNOFF CURVE NUMBER DATA
Pond #2: (Pre-developed)
w
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Soil/Surface Description
--------------------------------
Woods,good hydrologic condition
Grass, good hydrologic condition
Impervious Areas
Impervious
Area Adjustment Adjusted
CN acres %C %UC CN
---
----
70 ---------
4.830 ----- ----- ---
70.00
74 3.300 74.00
98 2.600 98.00
COMPOSITE AREA & WEIGHTED CN ---> 10.730 78.01 (78)
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007
1

Type.... SCS Unit Hyd. Summary Page 6.01
Name.... PRE-DEV Tag: Pre.10 Event: 10 yr
File.... F:\PROJECTS\424-04\CALCS\POND2-PRE.PPW
Storm... TypeII 24hr Tag: Pre.10
SCS UNIT HYDROGRAPH METHOD
STORM EVENT: 10 year storm
Duration = 24.0000 hrs Rain Depth = 5.1000 in
Rain Dir = C:\HAESTAD\PPKW\RAINFALL\
Rain File -ID = SCSTYPES.RNF - TypeII 24hr
Unit Hyd Type = Default Curvilinear
' HYG Dir = F:\PROJECTS\424-04\CALCS\
HYG File - ID = P2-PRE.HYG - PRE-DEV Pre.10
Tc = .5342 hrs
Drainage Area = 10.730 acres Runoff CN= 78

Computational Time Increment = .07122 hrs
~, Computed Peak Time 12.1787 hrs
Computed Peak Ftow 24.31 cfs
Time Increment for HYG File .0167 hrs
Peak Time, Interpolated Output = 12.1909 hrs
Peak Flow, Interpolated Output 24.24 cfs
_________________pRAINAGE AREA =____________

-------------------
ID:Pond #2 (Pre)
CN 78
Area = 10.730 acres
S = 2.8205 in
0.25 = .5641 in
Cumulative Runoff
-------------------
2.7968 in
2.501 ac-ft
HYG Volume... 2.501 ac-ft (area under HYG curve)
***** UNIT HYDROGRAPH PARAMETERS *****
Time Concentration, Tc = .53416 hrs (ID: Tc (Pre))
Computational Incr, Tm = .07122 hrs = 0.20000 Tp
Unit Hyd. Shape Factor = 483.432 (37.46% under rising limb)
K = 483.43/645.333, K = .7491 (also, K = 2/(1+(Tr/Tp))
Receding/Rising, Tr/Tp = 1.6698 (solved from K = .7491)
Unit peak, qp = 22.76 cfs
Unit peak time Tp = .35610 hrs
Unit receding limb, Tr = 1.42442 hrs
Total unit time, Tb = 1.78052 hrs

' S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007

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Type.... SCS Unit Hyd. Summary Page 6.02
Name.... PRE-DEV Tag: Pre100 Event: 100 yr
File.... F:\PROJECTS\424-04\CALCS\POND2-PRE.PPW
Storm... TypeII 24hr Tag: Pre100
SCS UNIT HYDROGRAPH METHOD
STORM EVENT: 100 year storm
Duration = 24.0000 hrs Rain Depth = 7.5000 in
Rain Dir = C:\HAESTAD\PPKW\RAINFALL\
Rain Fite -ID = SCSTYPES.RNF - TypeII 24hr
Unit Hyd Type =Default Curvilinear
HYG Dir = F:\PROJECTS\424-04\CALCS\
HYG Fite - ID = P2-PRE.HYG - PRE-DEV Pre100
Tc = .5342 hrs
Drainage Area = 10.730 acres Runoff CN= 78
Computational Time Increment = .07122 hrs
Computed Peak Time = 12.1787 hrs
Computed Peak Ftow = 42.95 cfs
Time Increment for HYG File .0167 hrs
Peak Time, Interpolated Output = 12.1909 hrs
Peak Flow, Interpolated Output 42.77 cfs

DRAINAGE AREA
ID:Pond #2 (Pre)
CN = 78
Area = 10.730 acres
S = 2.8205 in
0.25 = .5641 in

i
~l
Cumulative Runoff
-------------------
4.9308 in
4.409 ac-ft
HYG Volume... 4.409 ac-ft (area under HYG curve)
***** UNIT HYDROGRAPH PARAMETERS *****
Time Concentration, Tc = .53416 hrs (ID: Tc (Pre))
Computational Incr, Tm = .07122 hrs = 0.20000 Tp
Unit Hyd. Shape Factor = 483.432 (37.46 under rising limb)
K = 483.43/645.333, K = .7491 (also, K = 2/(1+(Tr/Tp))
Receding/Rising, Tr/Tp = 1.6698 (solved from K = .7491).
Unit peak, qp = 22.76 cfs
Unit peak time Tp = .35610 hrs
Unit receding limb, Tr = 1.42442 hrs
Total unit time, Tb = 1.78052 hrs

t
5/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007
1

Appendix A
Index of Starting Page Numbers for ID Names
----- P -----
POND #2 (PRE)... 5.01
PRE-DEV Pre.10... 6.01, 6.02
----- T -----
TC (PRE)... 4.01, 3.01, 3.03
----- W -----
Watershed... 1.01, 2.01, 2.02
a-1
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 10:34:35 Date: 01/26/2007

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WET DETENTION POND DESIGN
WET DETENTION POND #2
1

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STAGE-DISCHARGE FOR OVERFLOW WEIR
Project: Alexandria Park Apartments
Location: Wet Detention Pond #2
NC Hwy 68 & Whites Mill Road
' High Point, N.C.
Developer: Blue Ridge Companies
' Input Data:
Overflow Weir #1 Overflow Weir #Z
' Cw=
Elev.= 3.00 in.
849 Spillway crest Cw= 3.00 in.
Elev.= 850.5 Spillway crest
L= 3 ft., Weir length L= 12 ft., Weir length
Water Quality Release (orifice)
D= 2.5 in.
Elev.= 847 Invert elev. of release
Cd= 0.60 Orifice Coefficient
Emergency Spillway Dam Overtopping

' Cw= 3.00 in. Cw= 3.00 in.
Elev.= 0 Emerg. spillway crest Elev.= 853 Top of dam
L= 0 ft., Weir length L= 237 ft., Weir length

Sta a Increment
g 0.50 ft.
'

1 2 3 4 5 8 7 8 9
Stage WQ Weir #1 Weir #2 Combined Principal Emergency Dam Total
release Weir Spillway Spillway Overtopping Outflow
[ft.] [cfs] [cfs] [cfs] - _ [cfs] [cfs] [cfs] [cfs] [cam]
847.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
847.50 0.10 0.00 0.00 0.00 0.10 0.00 0.00 0.10
848.00 0.16 0.00 0.00 0.00 0.16 0.00 0.00 0.16
848.50 0.19 0.00 0.00 0.00 0.19 0.00 0.00 0.19
' 849.00 0.23 0.00 0.00 0.00 0.23 0.00 0.00 0.23
849.50 0.25 3.18 0.00 3.18 3.44 0.00 0.00 3.44
850.00 0.28 9.00 0.00 9.00 9.28 0.00 0.00 9.28
850.50 0.30 16.53 0.00 16.53 16.84 0.00 0.00 16.84
851.00 0.32 25.46 12.73 25.46 25.78 0.00 0.00 25.78
851.50 0.34 35.58 36.00 36.00 36.34 0.00 0.00 36.34
852.00 0.36 46.77 66.14 66.14 66.50 0.00 0.00 66.50
852.50 0.38 58.93 101.82 101.82 102.20 0.00 0.00 102.20
853.00 0.40 72.00 142.30 142.30 142.70 0.00 0.00 142.70
853.50 0.41 85.91 187.06 187.06 187.48 0.00 251.38 438.85
854.00 0.43 100.62 235.72 235.72 236.15 0.00 711.00 947.15
854.50 0.45 116.09 288.00 288.00 288.45 0.00 1306.19 1594.64
1 855.00 0.46 132.27 343.65 343.65 344.11 0.00 2011.01 2355.13
1
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WET DETENTION POND #2
WET DETENTION POND
DESIGN ROUTING
1

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Table of Contents
Table of Contents
'i
********************** MASTER SUMMARY **********************
Watershed....... Master Network Summary ............. 1.01
*************** NETWORK SUMMARIES (DETAILED) ***************
Watershed....... Dev.10
Executive Summary (Nodes) .......... 2.01
Watershed....... Dev100
Executive Summary (Nodes) .......... 2.02
****************** DESIGN STORMS SUMMARY *******************
HP Storms....... Design Storms ...................... 3.01
********************** RAINFALL DATA ***********************
TypeII 24hr.... Dev.10
Synthetic Cumulative Depth ......... 4.01
TypeII 24hr.... Dev100
Synthetic Cumulative Depth ......... 4.03
*****:**************** CN CALCULATIONS *********************
POND #2 (POST).. Runoff CN-Area ..................... 5.01
*********************** POND VOLUMES ***********************
POND #2......... Vol: Elev-Area ..................... 6.01
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Table of Contents
Table of Contents (continued)
11
******************** OUTLET STRUCTURES *********************
OUTLET DEVICE... Outlet Input Data .................. 7.01
*****~***************** POND ROUTING ~****~***********:*****
POND #2......... Pond E-V-Q Table ................... 8.01
POND #2 OUT Dev.10
Pond Routing Summary ............... 8.02
POND #2 OUT Dev100
Pond Routing Summary ............... 8.03
S/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

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Type.... Master Network Summary Page 1.01
Name.... Watershed
File.... F:\PROJECTS\424-04\CALCS\POND2-POST.PPW
MASTER DESIGN STORM SUMMARY
Default Network Design Starm File, ID HP.RNQ HP Storms
Total
Depth Rainfall
Return Event in Type RNF File RNF ID
------------ ------ ---------------- -------- ----------------
Dev.10 5.1000 Synthetic Curve SCSTYPES TypeII 24hr
Dev100 7.5000 Synthetic Curve SCSTYPES TypeII 24hr
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
Storage
Node ID ------- Type Event ---ac_ft-- Trun
*OUTLET JCT 10 2.202
*OUTLET JCT 100 4.153
POND #2 IN POND 10 2.833
POND #2 IN POND 100 4.816
POND #2 OUT POND 10 2.202
1.417
POND #2 OUT POND 100 4.153
2.195
POST-DEVELOPED AREA 10 2.833
POST-DEVELOPED AREA 100 4.816
Max
Qpeak Qpeak Max WSEL Pand
---hrs--- cfs ft ---ac=ft-
12.1409 9.85
12.0741 34.76
11.9238 53.01
11.9238 88.30
12.1409 9.85 850.04
12.0741 34.76 851.43
11.9238 53.01
11.9238 88.30
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Type.... Executive Summary (Nodes) Page 2.01
Name.... Watershed Event: 10 yr
File.... F:\PROJECTS\424-04\CALCS\POND2-POST.PPW
Storm... TypeII 24hr Tag: Dev.10
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = HP.RNQ HP Storms
Storm Tag Name = Dev.10
Description: 10-Year, 24-Hour
---------------------------------------
Data Type, File, ID = Synthetic Storm
Storm Frequency = 10 yr -------------
SCSTYPES.RNF ----------------
TypeII 24hr
Total Rainfall Depth= 5.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs En d= 24.0000 hrs
HYG Vol Qpeak Qpeak Max WSEL
-Node-ID--------- Type ---ac_ft--Trunk--hrs--- --cfs--- ---ft----
Outfall OUTLET JCT 2.202 12.1409 9.85
' POND #2 IN POND 2.833
POND #2 OUT POND 2.202 11.9238
12.1409 53.01
9.85 850.04
POST-DEVELOPED AREA 2.833 11.9238 53.01

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t S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Type.... Executive Summary (Nodes) Page 2.02
Name.... Watershed Event: 100 yr
File.... F:\PROJECTS\424-04\CALCS\POND2-POST.PPW
Storm... TypeII 24hr Tag: Dev100
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
i DEFAULT Design Storm File,ID = HP.RNQ HP Storms
Storm Tag Name = Dev100
Description: 100-Year, 24-Hour
---------------------------------------
-------------
----------------
Data Type, File, ID Synthetic Storm
Storm Frequency = 100 yr SCSTYPES.RNF TypeII 24hr
Total Rainfall Depth 7.5000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs En d= 24.0000 hrs
HYG Vol Qpeak Qpeak Max WSEL
Node
Trun_
hrs
ID
Type
ac=ft cfs
ft
-
-
---------
---
--
Outfall OUTLET JCT 4.153 --
---
12.0741 ----
--
--- ---
34.76
POND #2 IN POND 4.816
POND #Z OUT POND 4.153 11.9238
12.0741 88.30
34.76 851.43
POST-DEVELOPED AREA 4.816 11.9238 88.30

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,' S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Type.... Design Storms
Name.... HP Storms
Fite.... C:\HAESTAD\PPKW\RAINFALL\HP.RNQ
Title... Alexandria Park Apartments
NC Hwy 68 & Whites Milt Road
Blue Ridge Companies, Inc.
Pond #2 (Post-developed)
DESIGN STORMS SUMMARY
Design Storm File,ID = HP.RNQ HP Storms
Page 3.01
Storm Tag Name = Dev.10
Description__10_Year~_24_Hour___-r-_--_____^_______________`__________
Data Type, File, ID = Synthetic Storm SCSTYPES.RNF TypeTI 24hr
Storm Frequency = 10 yr
Total Rainfall Depth= 5.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
Storm Tag Name = Dev100
Description__100_Year__24_Hour________________________________^____-__
Data Type, File, ID = Synthetic Storm SCSTYPES.RNF TypeIl 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 7.5000 in
Duration Multiplier = 1
Resulting Duration = 24..0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
J

51N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

~YNe.... ~yi~~~~e~ ~~ ~umu~a~ ivC vcN~n
Name.... TypeII 24hr Tag: Dev.10 ~ age -.
Event: 10 yr
File.... C:\HAESTAD\PPKW\RAI
Title... 10-Year, 24-Hour NFALL\SCSTY PES.RNF
Storm... TypeII 24hr Tag: Dev.10
CUMUL ATIVE RAINF ALL DEPTHS (in )
Time ~ Output Time incr ement = .1000 hrs
hrs ~ Ti me on left represents time for first value in each row.

' ---------i------
.0000 -----------
.0000 -----------
.0052 --------------
.0103 -------
.0156 -------------
.0208
.5000 ~ .0262 .0315 .0370 .0424 .0480
1.0000 ~ .0536 .0592 .0649 .0706 .0764
1.5000 ~
2.0000 ~ .0823
.1122 .0881
.1184 .0941
.1245 .1001
.1308 .1061
.1371
2.5000 ~ .1435 .1498 .1563 .1628 .1694
3.0000 ~ .1760 .1826 .1893 .1961 .2029
3.5000 ~ .2098 .2166 .2236 .2306 .2377
4.0000 ~ .2448 .2520 .2593 .2667 .2742
4.5000 ~ .2818 .2895 .2973 .3052 .3132
5.0000 ~
5.5000 ~ .3213
.3634 .3295
.3721 .3378
.3809 .3462
.3898 .3548
.39$9
6.0000 ~ .4080 .4172 .4266 .4360 .4455
6.5000 ~ .4552 .4649 .4748 .4847 .4948
7.0000 ~
7.5000 ~ .5049
.5572 .5152
.5679 .5255
.5788 .5360
.5898 .5465
.6008
8.0000 ~ .6120 .6235 .6355 .6480 .6610
8.5000 ~ .6745 .6885 .7030 .7181 .7336
9.0000 ~
9.5000 ~ .7497
.8313 .7660
.8480 .7823
.8656 .7987
.8839 .8150
.9031
10.0000 ~ .9231 .9441 .9663 .9898 1.0145
10.5000 ~ 1.0404 1.0679 1.0975 1.1291 1.1628
11.0000 ~ 1.1985 1.2377 1.2817 1.3307 1.3845
11.5000 ~ 1.4433 1.5649 1.8072 2.1970 2.8961
12.0000 ~ 3.3813 3.4780 3.5631 3.6365 3.6983
12.5'000 ~
13.0000 ~ 3.7485
3.9372 3.7915
3.9676 3.8319
3.9966 3.8697
4.0241 3.9048
4.0502
13.5000 ~ 4.0749 4.09$4 4.1208 4.1422 4.1626
14.0000 ~ 4.1820 4.2007 4.2190 4.2370 4.2546
14.5000 ~
15.0000 ~ 4.2719
4.3529 4.2888
4.3680 4.3054
4.3827 4.3215
4.3972 4.3374
4.4112
15.5000 ~ 4.4249 4.4382 4.4512 4.4638 4.4761
16.0000 ~ 4.4880 4.4997 4.5112 4.5226 4.5339
16.5000 ~ 4.5451 4.5561 4.5670 4.5778 4.5884
17.0000 ~ 4.5989 4.6093 4.6196 4.6297 4.6397
17.5000 ~ 4.6496 4.6594 4.6690 4.6785 4.6879
18.0000 ~
18.5000 ~ 4.6971
4.7414 4.7062
4.7499 4.7152
4.7582 4.7241
4.7665 4.7328
4.7746
19.0000 ~ 4.7825 4.7904 4.7981 4.8057 4.8131
19.5000 ~ 4.8205 4.8277 4.8347 4.8417 4.8485
20.0000 ~
20.5000 ( 4.$552
4.8880 4.8618
4.8945 4.8684
4.9010 4.8750
4.9074 4.8815
4.9139
21.0000 ~ 4.9202 4.9266 4.9329 4.9392 4.9455
21.5000 ~ 4.9518 4.9580 4.9642 4.9704 4.9766
22.0000 ~ 4.9827 4.9888 4.9949 5.0010 5.0070

1
S/N: 621605B06A8F
PondPack Ver. 7.5 (765)
CPT Engineering & Surveying, Inc.
Compute Time: 16:17:38 Date: 04/16/2007

Type.... Synthetic Cumulative Depth Page 4.02
Name.... TypeII 24hr Tag: Dev.10 Event: 10 yr
File.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Title...
Storm... 10-Year, 24-Hour
TypeII 24hr Tag: Dev.10
CUMULATIVE RAINFALL DEPT HS (in)
Time
hrs ~ Output Time increment =
~ Time on left represents time for .1000 hrs
first value
in each row.
22.5000 ~ 5.0130 5.0190 5.0249 5.0308 5.0368
23.0000 ~ 5.0426 5.0485 5.0543 5.0601 5.0659
23.5000 ~ 5.0716 5.0774 5.0831 5.0887 5.0944
24.0000 ~ 5.1000

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5/N: 621605B06A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Type.... Synthetic Cumulative Depth
Name.... TypeII 24hr Tag: Dev100 Page 4.03
Event: 100 yr
File.... C:\HAE STAD\PPKW\RAINFALL\SCSTY PES.RNF
Title... 100-Ye
Storm... TypeII ar, 24-Hour
24hr Tag:
Dev100
CUMULATIVE RAINF ALL DEPTHS (in )
Time ~
hrs
i Output Time incr
Time on left represents ement = .1000
time for first hrs
value in
each row.
---_
---
---
.0000 ~ .0000 .OD76 .0152 .0229 .0306
.5000 ~ .0385 .0464 .0544 .0624 .0706
1.0000 ( .0788 .0871 .0954 .1039 .1124
1.5000 ~ .1210 .1296 .1384 .1472 .1561
2.0000 ~
2.5000 ( .1650
.2110 .1741
.2204 .1832
.2299 .1924
.2394 .2016
.2491
3.0000 ~ .2588 .2686 .2784 .2884 .2984
3.5000 ~ .3085 .3186 .3289 .3392 .3496
4.0000 ~
4.5000 ~ .3600
.4144 .3706
.4257 .3813
.4372 .3922
.4488 .4032
.4606
5.0000 ~ .4725 .4846 .4968 .5092 .5217
5.5000 ~ .5344 .5472 .5602 .5733 .5866
6.0000 ~ .6000 .6136 .6273 .6412 .6552
.` 6.5000 ~ .6694 .6837 .6982 .7128 .7276
7.0000 ~ .7425 .7576 .7728 .7882 .8037
7.5000 ~
8.0000 ~ .8194
.9000 .$352
.9169 .8512
.9345 .8673
.9529 .8836
.9720
8.5000 ~ .9919 1.0125 1.0339 1.0560 1.07$9
9.0000 ~ 1.1025 1.1265 1.1505 1.1745 1.1985
9.5000 ~
10.0000 ~ 1.2225
1.3575 1.2471
1.3884 1.2729
1.4211 1.2999
1.4556 1.3281
1.4919
10.5000 ~ 1.5300 1.5705 1.6140 1.6605 1.710D
11.0000 ~ 1.7625 1.8201 1.8849 1.9569 2.0361
11.5000 ~
12.0000 ~ 2.1225
4.9725 2.3013
5.1147 2.6577
5.2398 3.2309
5.3478 4.2590
5.4387
12.5000 ~ 5.5125 5.5758 5.6352 5.6907 5.7423
13.0000 ~ 5.7900 5.8347 5.8773 5.9178 5.9562
13.5000 ~ 5.9925 6.0270 6.0600 6.0915 6.1215
14.000D ~ 6.1500 6.1775 6.2045 6.2309 6.2568
14.5000 ~ 6.2822 6.3071 6.3314 6.3552 6.3785
15.0000 ~
15.5000 ~ 6.4013
6.5072 6.4235
6.5268 6.4452
6.5459 6.4664
6.5645 6.4871
6.5825
16.0000 ~ 6.6000 6.6172 6.6341 6.6509 6.6675
16.5000 ~ 6.6839 6.7001 6.7162 6.7320 6.7477
17.0000 (
17.5000 ~ 6.7631
6.8377 6.7784
6.8520 6.7935
6.8662 6.8084
6.8801 6.$231
6.8939
18.0000 ( 6.9075 6.9209 6.9341 6.9472 6.9600
18.5000 ~ 6.9727 6.9851 6.9974 7.0095 7.0214
19.0000 ~ 7.D331 7.0447 7.0560 7.0672 7.0781
19.5000 ~ 7.0889 7.0995 7.1099 7.1201 7.1302
20.0000 ~ 7.1400 7.1498 7.1594 7.1691 7.1787
20.5000 ~
21.0000 ~ 7.1883
7.2356 7.1978
7.2450 7.2074
7.2543 7.2168
7.2636 7.2263
7.2728
21.5000 ~ 7.2821 7.2912 7.3004 7.3094 7.3185
22.000D ~ 7.3275 7.3365 7.3454 7.3544 7.3632

S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Type....
Name.... Synthetic Cumulative Depth
TypeII 24hr Tag: Dev100 Page 4.04
Event: 100 yr
File.... C:\HAESTAD\PPKW\RAINFALL\SCSTYPES.RNF
Title...
Storm... 100-Year, 24-Hour
TypeII 24hr Tag: Dev100
CUMULATIVE RAINFALL DEPT HS (in)
Time
hrs ~ Output Time increment =
on left represents time for
Time
i .1000 hrs
first value
in each row.
---
--
22.5000 -
-
----
~ 7.3721 7.3808 7.3896 7.3983 7.4070
23.0000 ( 7.4156 7.4243 7.4328 7.4414 7.4498
I 23.5000 ~ 7.4583 7.4667 7.4751 7.4834 7.4918
24.0000 ~ 7.5000

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S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007
1

Type.... Runoff CN-Area Page 5.01
Name.... POND #2 (POST)
File.... F:\PROJECTS\424-04\CALCS\POND2-
Title... Pond #2 (Post-developed) POST.PPW
RUNOFF CURVE NUMBER DATA

. . ................
Pond•#2 (Post-developed) ................
.... . ..
.........
. .... .
.........................

' ---------------------------------------- --------- -------------------------
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN
Impervious Areas 98 acres
6.130 %C %UC CN
98.00
Open space, good condition 61 4.600 61.00
COMPOSITE AREA & WEIGHTED CN ---> 10.730 82.14 (82)
...........................................................................
...........................................................................
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S/N: 621605B06A8F
PondPack Ver. 7.5 (765)
CPT Engineering & Surveying, Inc.
Compute Time: 16:17:38 Date: 04/16/2007
1

Type.... Vol: Elev-Area Page 6.01
Name.... POND #2
File.... F:\PROJECTS\424-04\CALCS\POND2-POST.PPW
Title... Pond #2
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft) (sq.in) (acres ) (acres)
---------------
- (ac-ft)
------- (ac-fit)
---------------
-----------
847.00 ------------
----- ---------
.3780 -
-
.0000 .000 .000
848.00 .4530 1.2448 .415 .415
849.00 _=_=_ .4910 1.4156 .472 .887
850.00 ----- .5300 1.5311 .510 1.397
852.00 ----- .6150 1.7159 1.144 2.541
853.00 ----- .6610 1.9136 .638 3.179
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Metho d for R eservoir Volumes.
Volume = (1/3) * (E L2-EL1) * (Areal + Areal + sq.rt.( Area1*Area2))
where: EL1, EL2 = Lower and upper elevations of t he increment
Areal,Area2 =Areas computed for EL1, EL2, r espectively
' Volume = Incre mental volume between EL1 and EL2

r

S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

Type.... Pond Routing Summary
Name.... POND #2 OUT Tag: Dev.10
File.... F:\PROJECTS\424-04\CALCS\POND2-POST.PPW
Storm... TypeII 24hr Tag: Dev.10
LEVEL POOL ROUTING SUMMARY
HYG Dir = F:\PROJECTS\424-04\CALCS\
Inflow HYG file = P1-POST.HYG - POND #2 IN
Dev.10
Outflow HYG file = P1-POST.HYG - POND #2 OUT Dev.10
Pond Node Data = POND #2
Pond Volume Data = POND #2
Pond Outlet Data = OUTLET DEVICE
No Infiltration
INITIAL CONDITIONS
Starting WS Elev = 847.00 ft
Starting Volume = .000 ac-ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment = .0167 hrs
INFLOW/OUTFLOW HYDROGRAPH SUMMARY

,~ Peak Inflow = 53.01 cfs at 11.9238
Peak Outflow = 9.85 cfs at 12.1409
-------------- hrs
hrs
----
-----------------------------------
Peak Elevation = 850.04 ft
Peak_Storage____________1_417_ac_ft______________ ____
MA55 BALANCE (ac-ft)
------------
+ Initial Vol --------------
= .000
+ HYG Vol IN = 2.833
- Infiltration = .000
- HYG Vol OUT = 2.202
- Retained Vol = .631
Unrouted Vol = - 000 ac-ft
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(.010% of Inflow Volume)
Page 8.02
Event: 10 yr
5/N: 621605606A$F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007
1

Type.... Pond Routing Summary
Name.... POND #2 OUT Tag: Dev100 Page 8.03
Event: 100 yr
Fite.... F:\PROJECTS\424-04\CALCS\POND2-POST.PPW
Storm... TypeII 24hr Tag: Dev100
LEVEL POOL ROUTING SUMMARY
HYG Dir = F:\PROJECTS\424-04\CALCS\
Inflow HYG file = P1-POST.HYG - POND #2 IN Dev100
Outflow HYG file = P1-POST.HYG - POND #2 OUT Dev100
Pond Node Data = POND #2
Pond Volume Data = POND #2
Pond Outlet Data = OUTLET DEVICE
No Infiltration
INITIAL CONDITIONS
Starting WS Elev 847.00 ft
Starting Volume = .000 ac-ft
Starting Outflow = .00 cfs
Starting Infiltr. _ .00 cfs
Starting Total Qout= .00 cfs
Time Increment - .0167 hrs
INFLOW/OUTFLOW HYDROGRAPH SUMMARY
Peak Inflow = 88.30 cfs at 11.9238 hrs
Peak Outflow = 34.76 cfs at 12.0741
--------------------- hrs
----
----------------------------
Peak Elevation = 851.43 ft
Peak-Storage-_----------2_195-ac_ft-----------^-- ----
MASS-BALANCE-(ac_ft)
+ Initial Vol
+ HYG Voi IN
- Infiltration
- HYG Vol OUT
- Retained Vol
Unrouted Vol

1
.000
4.816
.000
4.153
.663
-.000 ac-ft (.007% of Inflow Volume)
S/N: 621605606A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

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Appendix A
Index of Starting Page Numbers for ID Names
----- H -----
HP Storms... 3.01
----- 0 -----
OUTLET DEVICE... 7.01
----- P -----
POND #2... 6.01, 8.01, 8.02, 8.03
POND #2 (POST)... 5.01, 4.01, 4.03
----- W -----
Watershed... 1.01, 2.01, 2.02
A-1
S/N: 621605806A8F CPT Engineering & Surveying, Inc.
PondPack Ver. 7.5 (765) Compute Time: 16:17:38 Date: 04/16/2007

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WET DETENTION POND DESIGN
WET DETENTION POND #Z
POND VOLUMES

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PERMANENT WATER QUALITY SURFACE AREA
TEMPORARY WATER QUALITY STORAGE PROVIDED

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