20061292 Ver 2_More Info Received_20110616

11111 11111 Jill 1111 FAST LANE PICKUP DATE t I PICKUP TIME
36627 DRIVER # OF PIECES-/WEIGHT _
1jAM E D-A Z"-'
BILL TO ' 'SHIPPER' RECEIVER 3RD PARTY
NEXT DAY CAR VAN ROUND TRIP CHARGES
FROM S & EC
11010 RAVEN RIDGE ROAD
RALEIGH, NC 27614
846-5900
PROJECTI_ ?r?
SIGNATURE ` l PRINT
828-0303
TO
COMPANY NAME
STREET ADDRESS!-,, 0 N. (I i?tjy
CITY ST t. ZIP,--, 4:,u
CONTACT NAME < r c:) 1 1,141
?7 S / L. L J r .-?-!` , . r
PHONE # ?;bq- L2
w DATE i r TIME
Environmental Consultants, PA
Road • Raleigh, North Carolina 27614 • Phone: [phone] • Fax: [phone]
www.SandEC.com
June 15, 2011
S&EC Project # 11258.P1
DWQ #: EXP 06-1292v2
NC Department of Environment and Natural Resources
Division of Water Quality
Wetlands, Buffers, Stormwater, Compliance and Permitting Unit (WeBSCaPe)
Attn: Karen Higgins/Lia Gilleski
512 N. Salisbury Street (9th floor)
Raleigh, NC 27604
Re: Request for More Information Response-EXPRESS REVIEW
Fairfield Farms Subdivisions (Sections 4, 5 & 6)
Cumberland County, NC
To Ms. Higgins and Mrs. Gilleski:
l?? n
r '(f?UJ/?
l0l?
On June 7, 2011, S&EC received a copy of the Request for More Information letter for the
Fairfield Farms Subdivision (Sections 4, 5 & 6). Since that time, the project engineer has been
working on the requested information. As such, please see the attached response letter from
Moorman, Kizer & Reitzel, Inc. along with referenced attachments.
We anticipate that this answers all of the DWQ's questions in order to complete the final review
process requested for the written concurrence of Water Quality Certification 3821. If you have
any further questions or any additional explanation is needed, please don't hesitate to call.
Sincerely,
SOIL & ENVIRONMENTAL CONSULTANTS, PA
Debbie Edwards
Environmental Specialist
ENGINEERS •
PLANNERS ?
SURVEYORS
MOORN! KIZER & REITZEL, INC.
June 14, 2011
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Wetlands, Buffers, Stormwater, Compliance and Permitting Unit
1650 Mail Service Center
Raleigh, North Carolina 27699-1650
Attn: Ms. Ua Gilleski
Re: Fairfield Farms Subdivision (Sections 4, 5 and 6)
DWQ #: EXP. 06-1292v2
Ms. Gilleski:
115 Broadfoot Ave.
P.O. Box 53774
Fayetteville, NC 28305
[phone]
Fax:[phone]
www.mkrinc.com
We are in receipt of your letter dated June 7, 2011, and offer the following responses to your
comments:
1) Wet/and Impacts: Lots 64 and 109 show portions of the proposed houses being
constructed on steep fill slopes It appears that these lots are not realistically
developable without additional lot fill or retaining walls Please revise the fill on these
lots and update the PCN wetland impacts if additional wetland impacts are necessary.
Conversations with the developer indicate that the overwhelming majority of the homes built in
previous sections of the subdivision are over crawl spaces, and it is certainly possible to build a
home on slopes as shown by utilizing a crawl space design or retaining walls. Also, please
remember that the lot layout drawings are meant to shown that a home could be built on the
lot, not what is actually proposed. It is possible that a floor plan could be designed to better fit
the lot.
It should also be noted that the perimeter of the wetlands to be preserved shall be protected by
installing continuous silt fence along and outside of the delineated wetland boundary, and that
no construction activity shall be allowed in any wetland area that is not specifically permitted.
This is indicated on the revised Grading Plans and on the Erosion Control Plan.
2) Please provide documentation that you have permission to place rip rap from the outlet
of the wet pond on the Tonya Strickland property.
The graphics for the rip rap apron were not drawn to scale. The apron can be installed without
extending onto the adjacent property, and the graphics have been revised to reflect the actual
design. (Please see Item #3 below.)
3) Please provide velocity calculations for the 10-storm discharge from both wet ponds,
and the sizing information for the energy dissipater pads. In particular, please ensure
that the discharge velocity from pond 2 to the adjacent wetland is less than 2fps
Velocity calculations and energy dissipater sizing for all discharge points are attached.
Response to DWQ WeRScaPe Comments
Fairfield Farms, Section 4, 5 & 6
June 14, 2011
4) Please show the permanent pole top and bottom elevations of the vegetated shelf in
the plan views for both wet detention basins (and probably hatch the shelf differently).
Moreover, please correct the discrepancy in the permanent pool elevation for wet pond
1(126.5 vs 127) so that both the report and the grading plan match.
The requested information has been added to the plans, the normal pool areas and vegetated
shelf have been re-hatched to be more clearly understood and the elevation discrepancies have
been corrected.
5) The width at the top of the forebay berm measures 4 tt in the plan view and not the 5
ft indicated in the cross section. Please revise the grading to ensure a minimum of 5 ft.
The grading has been revised as requested. Please note that the additional width for the
forebay weir reduced the volume of the temporary pool (VWQ) to less than the minimum
required. The discharge control weir elevation has therefore been raised to provide additional
storage volume. A revised PondPack report and Narrative of Design are attached.
I trust that these responses will satisfy your request for more information. If you should have
additional comments or questions, please do not hesitate to contact me or Mr. Jimmy Kizer at
[phone].
Thank you for your assistance with this project.
Respectfully submitted,
Reitzel, Inc.
Mo man, Kizer &
Blake Ball
Senior Civil Designer
Attachments: 2 copies Revised Plan Sheets
2 copies Revised Narrative
2 copies Revised Wet Detention Basin Supplement for Basin 1
2 copies Revised PondPack report for Basin 1 - Developed Condition
2 copies each velocity calculations and rip rap dissipater calculations
Cc: File 98-1702-01
Brolanco (Mr. Dohn Broadwell, Sr.)
Soil and Environmental Consultants, PA (Mr. Bob Zarzecki)
g. Icurrentjobslbrolanco corporationl98-1702-01 fairfield farm - future sectionsicorrespondencelsection fourlresponse to dwq wetlands 9june2011.doc
2
Narrative of Design
for
Stormwater Management Facilities
At
Fairfield Farms Subdivision
Sections Four, Five & Six
Brolanco Corporation
Carver's Creek Township
Cumberland County, North Carolina
May 2011
Revised June 2011
Prepared by.,
Moorman, Kizer & Reitzel, Inc.
NC Firm License F-0106
P.O. Box 53774
115 Broadfoot Avenue
Fayetteville, North Carolina 28305
[phone]
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Proiect Description
The project involves the construction of up to 110 lots on West Summerchase Road off of Ramsey
Street, at the rear of the existing Fairfield Farms Subdivision. Work will include sewer and water for
Public Works Commission, storm drainage for the City of Fayetteville and streets to City of
Fayetteville standards with 27 foot back to back asphalt pavement with concrete curb and gutter.
Due to portions of the streets being designed in very deep cut, this project will include lot
aradina. The in areas of deep roadway cut, lots will be graded to eliminate steep banks from the
lots to the street and create a more favorable house construction area. In area where the building
envelopes are below street grade, the lots will, to the maximum extent possible, be filled to direct
runoff from impervious surfaces toward the streets, where it will be collected and conveyed to the
treatment facilities. The wet detention basin will be sized to accommodate the maximum impervious
area allowed by the Homeowner's Association documents and treat the runoff to remove 90% of the
Total Suspended Solids (TSS). There are some areas that cannot be drained to the Wet Detention
Basin, but by treating the runoff from the majority of the site to remove 90% of the TSS, rather
than the required minimum of 85%, the "average" removal rate will meet the 85% minimum.
All construction projects exceeding one acre in area, as this project does, are required to comply
with the National Pollution Discharge Elimination System (NPDES) Phase II Stormwater Program.
The City of Fayetteville (NC) is the "Regulated Entity", and has adopted a Stormwater Control
Ordinance and related development regulations, in part, to meet the requirements of the Phase II
Program (Sec.23-20(b)).
To determine the design requirements for compliance with the various ordinances, the project must
be classified in regards to the receiving watercourse designation, the proposed use and the
impervious cover expected at buildout.
Desian Reauirements
The City of Fayetteville Stormwater Ordinance and Water Supply Watershed Management and
Protection Ordinance require that the peak stormwater discharge rates for High Density Projects
within the "non-Critical" Water Supply Watershed Protection Area be limited to the predeveloped
rate, and that the discharge from the runoff produced by a one-inch rainfall event be treated to
remove a minimum of 85 percent of the Total Suspended Solids conveyed. The primary treatment
system will be Wet Detention Basins in accordance with the Water Supply Watershed Management
and Protection Ordinance. The stored volume must be released over a period of at least two days,
but less than five days. The design and construction of the stormwater management facilities must
be in accordance with the requirements of the North Carolina Department of Environment and
Natural Resources, Division of Water Quality (NC DENR-DWQ) Stormwater Best Management
Practices Manual (BMP Manual).
Existing topography dictates that the project will require two Wet Detention Basins. The larger
basin, designated as Basin 1, is located near the southeastern corner of the project, and the smaller
basin, designated as Basin 2, is located near the northwestern corner of the property. The peak flow
analysis will be performed at the two main discharge points from the site. Discharge Point 1 will
represent the flow that leaves the site near the southeastern corner of the project, near Basin 1.
Discharge Point 2 will represent the flow that leaves the site near the northwestern corner of the
project, near Basin 2.
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April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Existing Conditions
Site Description
The site is located at the western end of the previously developed phases of Fairfield Farms
Subdivision, west of Ramsey Street (U. S. Highway 401 North), north of Andrews Road and South of
McCloskey Road. The site has been timbered in the past, and is mostly wooded with medium sized
pines and scrub oaks in "fair" condition (some leaf litter and brush). Existing grades vary from 0.5%
to 12%. The majority of the site drains from west to east towards the existing subdivision, into an
existing swale which flows to the south. A small portion at the northwestern corner of the property
drains towards the north. A drainage map is attached.
There are jurisdictional wetlands on the site, as shown on the attached copy of the Wetlands Map
signed by a representative of the U.S. Army Corps of Engineers (USACE) on February 26, 2004. The
proposed wetlands impact areas are as shown on the attached Wetlands Impact Map, dated
February 27, 2008. A copy of the General Permit (Nationwide Permit 29) under Section 404 of the
Clean Water Act (33 USC 1344) to impact up to 0.488 acres of Jurisdictional Wetlands, dated
September 25, 2008 (SAW-2003-01163) is attached.
Adiacent Property
The adjacent property to the east is the existing Fairfield Farms Subdivision with existing single
family homes and is zoned R10. Property to the north is zoned PND (Planned Neighborhood
Development - Conditional Use) and R10 and is currently undeveloped. The property to the west is
owned by the State of North Carolina and the Nature Conservancy and will not be developed. The
property to the south is developed as large single family home tracts with existing homes, but is
zoned PND. The only offsite area tributary to the proposed stormwater management facilities is a
small area to the west, within the property owned by the State and Nature Conservancy to the west
of the site.
Soils
The Natural Resources Conservation Service (NRCS) Web Soil Survey was used to determine the
predominant soils on the site. The soils shown in this project area are as follows, listed according to
the coverage on the site:
Vauduse loamy sand, 8 to 15 peroent dopes (VaD, N39% owe-age, Hydrologic Group C)
Gilead loamy sand, 2 to 8 percent slope (GdB, N30% coverage, Hydrologic Group C)
Candor sand,l to 8 percent slopes (CaB, N 17% aoverage, Hydrologic Group A)
Johnston loam QT, N60/o ooverage, Hydrologic Group D)
Blaney loamy sand, 8 to 15 percent slopes (BaD, N20/o coverage, Hydrologic Group B)
Blaney loamy sand, 2 to 8 percent slopes (BaB, N30/o overage, Hydrologic Group B)
Pantego loam (Pg, N3% oa)erage, Hydrologic Group B/D)
A copy of the Web Soils Report and an excerpt from the Cumberland-Hoke Soil Survey for the area
is attached.
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April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Watershed Classification
The receiving watercourses are tributaries of Carvers Creek (Cape Fear Basin, Stream Index No.18-
24), which is currently classified as WS-IV, B waters. This is a Water Supply Watershed designation,
which is confirmed by review of the City of Fayetteville Watershed Protection Map. Therefore the
project is also subject to the Watershed Protection Ordinance of the City of Fayetteville, which limits
the density and impervious cover of the development in addition to the water quality and peak
discharge requirements of the Stormwater Ordinance.
Proposed Developed Condition
The proposed use is detached single family residential. The project will include up to 110 single
family lots.
The proposed impervious cover will be estimated using the design areas of roadway and sidewalk
and an estimate of the areas to be covered by homes, driveways, porches, etc. as follows:
This project covers a total area of 2,381,318 square feet (54.668 acres). Areas outside of the project
boundaries that are tributary to the Wet Detention Basins cover 135,623 square feet (3.113 acres).
Areas within the boundaries of the project that are not tributary to the Wet Detention Basins cover
262,376 square feet (6.023 acres).
The proposed streets (27' back of curb to back of curb with 24" "rolled" curb and gutter) will cover
207,522 square feet (4.764 acres) and the proposed public sidewalk will cover 27,073 square feet
(0.622 acres). Assuming half of the lots will have sidewalk along the frontage, the average driveway
length within the rights of way is 9.5 feet (11.5' w/sidewalk & 7.5' w/o). At 25' wide, there will be
26,125 square feet of driveway (25'W x 9.5L x 110 Lots) within the rights of way. This totals
260,720 square feet (5.985 acres) of impervious cover for the rights of way.
A typical lot will include a detached residence with an average impervious cover of 2,550 square
feet, a 25 foot wide by 31 foot long drive (775 square feet), a 4 foot wide by 35 foot long walkway
(140 square feet) and a 10 foot by 12 foot patio (120 square feet). This is a total of 3,585 square
feet of impervious area per lot, which will be rounded up to 4,000 square feet for calculation
purposes to take into account the installation of storage sheds, additional walkways and other
hardscape by homeowners. The maximum impervious cover of 4,000 square feet per lot will be
mandated by restrictive covenants in the Homeowner's Association documents. For 110 lots, this
equates to 440,000 square feet (10.101 acres) of impervious area for the lots within the project.
Adding the 440,000 square feet of impervious cover from the lot construction to the 260,720 square
feet of impervious cover in the streets and sidewalks results in a maximum total impervious cover of
700,720 square feet (16.086 acres) for the development, or 29.43% coverage. Developments within
the Water Supply Watershed Protection Areas with 24% or greater coverage, or those with curb,
gutter and storm drainage are considered High Density developments for purposes of determining
the stormwater management requirements under the Watershed Protection Ordinance.
For purpose of estimating the runoff from the developed site, it is assumed that, with protective
covenants in the Homeowners Association documents, the condition of the wooded areas within the
wetlands not impacted by construction, and the offsite area within the property to the west owned
by the State of North Carolina and the Nature Conservancy will improve over time from "fair"
4 of 17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
condition to "good" condition (leaf litter or brush cover over the majority of the area). It is further
assumed that lot areas and rights of way outside of the wetland areas that are not covered with
impervious surface will be cleared or maintained as "open space" (lawns, landscaping, etc.) in
"good" condition.
The total right of way area is 365,194 square feet. The rights of way will include 260,720 square
feet of impervious cover, as outlined above. The areas within the rights of way will be calculated as
71.39% impervious and 28.61% "open space". Because the location of the driveways is not set, the
impervious cover percentage will be used to determine runoff potential from all areas within rights
of way.
The lot areas, excluding the stormwater management areas, that are not protected as wetlands
cover 1,547,329 square feet. Using the previously calculated 440,000 square feet of impervious
cover for the lots, the average impervious cover for the lot areas is 28.44%. Because the location of
the improvements on each lot are not set, the impervious cover percentage will be used to
determine runoff potential from all areas within lots that are not protected as wetlands.
The areas within the lots dedicated to stormwater management contain 116,639 square feet (2.678
acres). 101,277 square feet will be used to construct and maintain the wet detention basin and will
considered "open space" in "good" condition for the purpose of runoff calculations. The remaining
15,362 square feet of this area are protected wetlands, and will be left undisturbed.
Areas that are protected as wetlands cover 265,544 (6.096 acres) square feet. These areas are
currently covered with small pines and "scrub" oak with some brush and leaf litter covering the soil
and are classified as being in "fair" condition for the predeveloped condition. With protective
covenants, the area should revert to a more natural state, with a good cover of leaf litter or brush
and will be classified as being in "good" condition for the developed condition.
The remaining 101,974 square feet (2.341 acres) of the site will be "open space". 70,511 square
feet will be used as drainage easements. The open space areas will be modeled as lawn and
landscaping in "good" condition.
Design of Stormwater Management Facilities
The Best Management Practices manual outlines the requirements for the design of wet detention
basins for water quality purposes. The requirements are met as follows:
Required Surface Area
The required surface are of the permanent pool is based on the size and impervious cover of the
area tributary to the basin and the average depth of the basin. The drainage areas and impervious
cover for each of the basins are as follows:

Basin Drainage Area
A SF Impervious Area
SF Impervious Cover
Ia
Basin 1 1,987,431 598,404 30.11
Basin 2 2671134 70,982 26.57
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April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
The BMP Manual requires that the permanent pool elevation be within 0.5' of the Seasonal High
Water Table. The seasonal high water table was determined by KAM Engineering Services. A copy of
the report is attached. The lower of the two values given for each basin were used to determine if
additional measures would be required to prevent adverse impacts to wetlands, surface waters or
groundwater elevations. The seasonal high water elevations and corresponding permanent pool
elevations for each basin are as follows:
Relation of Seasonal High Water Table to Permanent Pool

Basin Seasonal High Water
Table Elevation 1 Seasonal High Water
Table Elevation 2 Proposed Permanent
Pool Elevation
Basin 1 127.2 130.3 127.00
Basin 2 164.6 161.3 161.50
The basins were modeled in AutoCAD with and the stage/storage values were calculated from the
areas of the contours. The proposed grading for the basins is shown on the attached plans. The
calculated storage capacities for the basins are shown in the tables below.
Basin 1 Stage/Storage

tage

epth
(FT)
Forebay
Surface
Area
(SF)
Forebay
Incremental
Volume
(CF)
Forebay
Total
Volume
(CF) Non-
Forebay
Surface
Area
(SF) Non-
Forebay
Incremental
Volume
(CF) Non-
Forebay
Total
Volume
(CF)
Total
Surface
Area
(SF)

Total
Volume
(CF)

omments
120.00 -1.00 2,605 0 0 12,744 0 0 15,349
121.00 0.00 3,417 3,002 3,002 14,158 13,445 13,445 17,575 16,446 Top of Sediment Storage
122.00 1.00 3,930 3,671 6,672 15,628 14,887 28,332 19,558 35,004
123.00 2.00 4,496 4,210 10,882 17,155 16,386 44,717 21,651 55,600
124.00 3.00 5,033 4,762 15,644 18,739 17,941 62,658 23,772 78,303
125.00 4.00 5,622 5,325 20,969 20,379 19,553 82,212 26,001 103,181
126.00 5.00 6,236 5,926 26,895 22,075 21,221 103,433 28,311 130,328
126.50 5.50 6,552 3,197 30,092 22,945 11,254 114,687 29,497 144,779 Toe of Safety Bench
127.00 6.00 6,875 3,356 33,448 32,800 13,863 128,550 39,675 161,999 Permanent Pool
127.50 6.50 36,160 17,233 145,784 36,160 179,232 Top of Safety Bench
128.00 7.00 37,480 18,409 164,193 37,480 197,641
128.50 7.50 38,725 19,050 183,243 38,326 216,691
128.60 7.60 39,005 3,886 183,911 39,005 214872 Top of Riser
129.00 8.00 40,738 19,864 203,107 40,738 236,555
129.50 8.50 41,826 20,640 223,747 41,826 257,195
130.00 9.00 42,919 21,186 244,933 42,919 278,381
131.00 10.00 45,164 44,037 288,969 45,164 322,417
132.00 11.00 47,992 46,571 335,540 47,992 368,988
133.00 12.00 50,351 49,166 384,706 50,351 418,154 To of Dike
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Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Basin 2 Stage/Storage

tage

epth
(FT)
Forebay
Surface
Area
(SF)
Forebay
Incremental
Volume
(CF)
Forebay
Total
Volume
(CF) Non-
Forebay
Surface
Area
(SF) Non-
Forebay
Incremental
Volume
(CF) Non-
Forebay
Total
Volume
(CF)
Total
Surface
Area
(SF)

Total
Volume
(CF)

omments
155.00 -1.00 218 0 0 296 0 0 514 0
156.00 0.00 312 0 0 709 0 0 1,021 0 Top/ Sediment Storage
157.00 1.00 420 365 365 1,268 975 975 1,688 1,340
158.00 2.00 541 480 844 1,914 1,580 2,555 2,455 3,399
159.00 3.00 675 607 1,451 2,588 2,242 4,797 3,262 6,248
160.00 4.00 820 746 2,197 3,294 2,934 7,731 4,114 9,928
161.00 5.00 979 899 3,096 4,021 3,651 11,382 5,000 14,478 Toe of Vegetated Shelf
161.50 5.50 1,063 510 3,606 5,302 2,323 13,706 6,365 17,312 Permanent Pool
162.00 6.00 7,856 3,269 16,974 7,856 20,581 Top of Vegetated Shelf
162.60 6.60 8,533 4,915 21,889 8,533 25,496 Top of Riser
163.00 7.00 8,995 3,505 25,395 8,995 29,001
163.50 7.50 9,586 4,645 30,039 9,586 33,646 Emergency Spillway
164.00 8.00 10,191 4,944 34,983 10,191 38,589
165.00 9.00 11,444 10,811 45,794 11,444 49,401 Top of Dike
The average depth is calculated using Method 2 from the BMP manual. Method 2 is as follows:
d - 0.25 x ?1 + f?bot shelf + C Abot shelf + Abot pond X C Depth
ave -
Aperm _ pool 2 Abot _ shelf
where:
ddVe = average depth in feet rounded to closest 0.5 foot
Abot shelf = area at bottom of vegetated shelf (includes forebay) in Square Feet
Apertn pool = area at Permanent Pool elevation (includes forebay) in Square Feet
Abot pond = area of bottom of pond at top of sediment storage (does not include forebay) in
Square Feet
Depth = depth between bottom of vegetated shelf and top of sediment storage
For each basin, the calculations are as follows:
Description Basin 1 Basin 2
Permanent Pool Elevation (ft, MSL) 127.00 161.50
Permanent Pool Area (A erm ool )(SF) 32,799 6,635
Bottom of Vegetated Shelf Elevation (ft, MSL) 126.50 161.00
Bottom of Shelf Area (Abot shelf) (SF) 29,078 5,000
Bottom of Pond Elevation (ft, MSL) 121.00 156.00
Bottom of Pond Area (Abot ond)(SF) 14158 709
Depth (Bottom of Shelf-Bottom of Pond)(ft) 5.50 5.00
Average Depth (Method 2)(ft) 4.561 (4.5) 3.301(3.5)
7 of 17
A,orll 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
From the Surface Area/Drainage Area tables (SA/DA) for 90% Total Suspended Solid (TSS) removal,
the reauired ratios for each basin are as follows:
Description Basin 1 Basin 2
Impervious Cover (%) 30 27
Average Depth (ft) 4.5 3.5
SA/DA ratio (%) (min) 1.50 1.65
Drainage Area (SF) 1,987,434 267,134
Minimum Surface Area Required (SF) 29,812 4,408
Surface Area Provided (SF) 32,799 6,365
SA/DA ration (%) provided 1.65(OK) 2.38(OK)
Reauired Storaae (Water Ouality)
The required volume of water to be stored (Water Quality Volume) is equal to the runoff from the
first 1 inch of a storm event, and is calculated as follows:
VwQ = 3630 xRDxRvxA
where:
VwQ = Water Quality Volume (Cubic Feet)
3630 = cubic feet per acre inch
RD = Rainfall Depth (inches)
R, = Runoff Depth (inches per inch of rainfall)
A = Drainage Area (acres)
and;
Rv = 0.05 + 0.9(Ia )
where:
Ia = Impervious Cover Ratio
The required water quality storage volume (VWQ) is for the first one inch of rainfall (RD =1'). The
following table summarized the required volume calculations.
Basin Basin 1 Basin 2
Drainage Area (SF) 1,987,431 267,134
Drainage Area (A) (Acres) 45.625 6.133
Impervious Area (SF) 598,404 69,504
Impervious Cover Ratio (Ia) .3011 .2657
Runoff Depth (R,)(in./in of rainfall) 0.3210 0.2842
Required Water Quality Volume (VW Q)( ft3) 53,162 5,915
Quality Volume (Vw) Provided ( ft3) 56,909 (OK) 8,184 (OK)
The preceding calculations support that the basins have been designed with adequate surface area
and volume to provide 90% removal of Total Suspended Solids.
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April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
The requirements of the ordinance state that the runoff from the Built-Upon Area (BUA) be treated
to remove 85% of the total suspended solids. Review of the calculations above shows that of 77,720
square feet of proposed impervious area, runoff from 669,386 square feet is directed to the wet
detention basins (95.5% of the total). Treating that runoff to capture 90% of the TSS results in an
overall capture rate of approximately 86%, which meets the intent of the ordinance.
Hydraulic Calculations
The hydraulic performance must be analyzed to determine if the stored volume is released at an
appropriate rate; and that the basins are adequately designed to attenuate the peak flow from the
developed condition to no more that the peak rate from the predeveloped condition for the design
storms, and to safely accommodate the flows from larger storms up to the 100-year 24-hour event.
Runoff Calculations
The performance of the basin will be calculated using precipitation data from the National Weather
Service (NOAH-NWS) with Type II distribution for the 1-year, 10-year, 25-year and 100-year storm
events. Hydrographs will be developed for both the predeveloped and developed condition. The 1-
year and 10-year storm hydrographs for the predeveloped condition will be compared to the
hydrographs for the same storms to determine compliance with the peak flow attenuation
requirements. The hydrographs for the developed condition of the areas tributary to the basins will
be routed through the basins to develop hydrographs representing the attenuated flow from the
basins. These hydrographs will be added to those from the areas that are not tributary to the basin
to determine the peak discharge from the site, as a whole, for the developed condition. The peak
discharge for the developed condition may not exceed that from the predeveloped condition.
The hydrographs for the 25-year and 100-year storm events will be used to determine the adequacy
of the outlet structure and emergency spillway.
The drainage areas were modeled using the NRCS (formerly SCS) method in PondPack M (Bentley
Systems). The required information includes the drainage areas and subareas, the existing and
proposed ground cover to determine a composite Runoff Curve Number and the time of
concentration for each of the subareas.
The drainage areas for both the existing (predeveloped) and proposed (developed) conditions were
delineated in AutoCAD and curve numbers assigned based on the conditions outlined above. Please
reference the drainage area map for the location of the subareas. A summary of the data used to
determine the runoff curve number for the project is as follows.
9of17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Runoff Curve Number Calculation
Predeveloped Condition

Draina a Area
Subarea
Area SF Curve
Number
Not Tributary 1
Woods Fair Condtion "A" Soils 7,183 36
Woods Fair Condtion "B" Soils 21 60
Woods Fair Condtion "C" Soils 43,161 73
Woods Fair Condtion "D" Soils 54,825 79
Total 105,190 74

Not Tributary 2
Woods Fair Condtion "C" Soils 74,364 73
Woods Fair Condtion "D" Soils 22,598 79
Total 96,963 74

Not Tributary 3
Woods Fair Condtion "B" Soils 20,487 60
Woods Fair Condtion "C" Soils 15,770 73
Woods Fair Condtion, "D" Soils 23,977 79
Total 60,235 71

Tributary to Basin 1
Newly Graded, "A" Soils 34,857 77
Woods Fair Condtion, "A" Soils 219,792 36
Woods Fair Condtion, "B" Soils 59,357 60
Woods Fair Condtion, "C" Soils 1,574,753 73
Woods Fair Condtion, "D" Soils 98,675 79
Total 1,987,434 69

Tributary to Basin 2
Newly Graded "A" Soils 62,230 77
Woods Fair Condtion, "A" Soils 65,580 36
Woods Fair Condtion, "B" Soils 36,380 60
Woods Fair Condtion, "C" Soils 78,937 73
Woods Fair Condtion, "D" Soils 24,008 79
Total 267,134 64
10 of 17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
broianco Corporation
Developed Condition
Not Tributary 1
Impervious Cover 13,271 98
Basin Lot "C" Soils 257 74
Basin Lot "D" Soils 7,450 80
Open Space Good Condition "A" Soils 2,133 39
Open Space Good Condition, "B" Soils 15 61
Open Space Good Condition "C" Soils 20,831 74
Open Space Good Condition, "D" Soils 10,420 80
Woods Good Condtion "A" Soils 4,203 30
Woods Good Condtion "C" Soils 13,794 70
Woods Good Condtion "D" Soils 32,816 77
Total 105,190 76

Not Tributary 2
Impervious Cover 7,520 98
Drainage Swale "C" Soils 50,797 74
Drainage Swale "D" Soils 19,705 80
Open Space Good Condition "C" Soils 16,863 74
Open Space Good Condition "D" Soils 2,064 80
Total 96,949 77

Not Tributary 3
Impervious Cover 10,544 98
Basin Lot "B" Soils 9,727 61
Basin Lot "C" Soils 1,951 74
Basin Lot "D" Soils 11,479 80
Open Space Good Condition "B" Soils 7,700 61
Open Space Good Condition "C" Soils 9,892 74
Open Space Good Condition "D" Soils 8,944 80
Total 60,237 76

Tributary to Basin 1
Impervious Cover 598,404 98
Basin Lot "B" Soils 30,794 61
Basin Lot "C" Soils 15,751 74
Basin Lot "D" Soils 894 80
Open Space Good Condition "A" Soils 125,774 39
Open Space Good Condition "C" Soils 817,904 74
Open Space Good Condition "D" Soils 65,338 80
Woods Good Condtion "A" Soils 55,420 30
Woods Good Condtion "B" Soils 28,563 55
Woods Good Condtion "C" Soils 248,588 70
Total 1,987,431 77
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April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation

Tributary to Basin 2
Impervious Cover 70,982 98
Basin Lot "C" Soils 1,424 74
Basin Lot "D" Soils 21,549 80
Open Space Good Condition "A" Soils 60,030 39
Open Space Good Condition "B" Soils 15,095 61
Open Space Good Condition "C" Soils 47,314 74
Open Space Good Condition "D" Soils 1,487 80
Woods GoodCondtion "A" Soils 34,102 30
Woods Good Condtion "B" Soils 15,151
55

The Time of Concentration for each subarea is calculated using the SCS Lag method for overland
flow and, if applicable, a calculated flow time in the storm drainage system from the StormCAD
model. The results are as follows:
Predeveloned Time of Concentration

Subarea Hydraulic
Length
(ft)
Slope
(ft/ft)
Runoff Curve
Number Time of
Concentration
(Min.)
Not Tributary 1 648 0.039 74 14
Not Tributary 2 2715 0.012 74 78
Not Tributary 3 1250 0.035 72 26
Tributary to Basin 1 1637 0.042 72 29
Tributary to Basin 2 1362 0.033 72 28
Develoned Time of Concentration

Subarea Hydraulic
Length
(ft)
Slope
(ft/ft) Runoff
Curve
Number Overland
Time
(Min.) System
Time
(Min.) Time of
Concentration
(Min.)
Not Tributary 1 648 0.039 72 14 n/a 14
Not Tributary 2 2715 0.012 74 78 n/a 78
Not Tributary 3 1250 0.035 72 16 n/a 26
Tributary to Basin 1 308 0.017 72 12.1 13.8 26
Tributary to Basin 2 507 0.011 74 22.1 1.1 23
The following table provides a summary of the peak discharges for each of the modeled storms.
Complete results are included in the attached Pond Pack printouts,
12 of 17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Basin 1 Predeveloped Peak Discharge Rates
Description 1-year
Storm 10-year
Storm 25-year
Storm 100-year
Storm
Basin 1 Peak Flow CFS 22.18 89.73 126.36 192.31
Basin 1 Time to Peak Min 732 732 732 730
Not Tributary 2 Peak Flow CFS 0.81 2.66 3.64 5.36
Not Tributary 2 Time to Peak Min 766 766 758 758
Not Tributary 3 Peak Flow (CFS) 0.88 3.20 4.44 6.63
Not Tributary 3 Time to Peak Min 730 730 730 728
Discharge Point 1 Peak Flow* CFS 23.40 94.25 132.65 201.77
Discharge Point 1 Time to Peak Min 732 732 732 730
*Please note that the total peak discharge does not equal the sum of the peak discharges from the
subareas due to the difference in times to peak.
Basin 2 Predeveloped Peak Discharge Rates
Description 1-year
Storm 10-year
Storm 25-year
Storm 100-year
Storm
Basin 2 Peak Flow CFS 1.81 9.83 14.54 23.16
Basin 2 Time to Peak (Min) 734 730 730 730
Not Tributary 1 Peak Flow CFS 2.64 8.40 11.36 16.50
Not Tributary 1 Time to Peak (Min) 722 722 722 722
Discharge Point 2 Peak Flow* CFS 3.79 16.28 23.36 35.84
Discharge Point 2 Time to Peak (Min) 726 726 726 726
*Please note that the total peak discharge does not equal the sum of the peak discharges from the
subareas due to the difference in times to peak.
Outlet Structure Desian
Basin 1
The outlet structure for Basin 1 consists of a concrete box riser with 60" x 60" interior dimensions.
The top of the structure is to be set at elevation 130.80. A 6-inch diameter drawdown pipe will be
installed in the riser at the normal pool elevation of 127.00 and will extend to 12 inches below the
normal pool to minimize clogging during drawdown periods. The drawdown pipe will have an orifice
3.125 inches (3-1/8") in diameter to control the drawdown rate. 2-foot wide rectangular weirs are to
be cut into each side of the riser with inverts of 128.60. These four weirs will control the 1-year and
10-year peak flows. The basin volume between the control weir elevation of 128.60 and the normal
pool elevation of 127.00 is the treatment volume and equals 56,909 cubic feet, which exceeds the
required minimum of 53,131 cubic feet. Flow from the riser structure will be conveyed using a 48"
reinforced concrete pipe (RCP) with an upstream invert of 123.00 (at the riser) and a downstream
invert of 122.36. The riser structure shall have an anti-vortex/trash rack assembly provided that will
extend from elevation 131.50 (above the maximum water elevation for the 25-year storm) to
elevation 126.50 (6" below the normal pool elevation). An emergency spillway will be provided to
minimize the chance of catastrophic failure of the dike. This spillway will be a 20 feet wide broad
crested trapezoidal weir, with 3:1 side slopes, and will have a weir elevation of 131.40. The top of
dike elevation is 133.00.
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April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Basin 2
The outlet structure for Basin 2 consists of a corrugated aluminum riser with a diameter of 30
inches. The top of the riser is to be set at elevation 162.60. A 4-inch diameter drawdown pipe will
be installed in the riser at the normal pool elevation of 161.50 and will extend to 12 inches below
the normal pool to minimize clogging during drawdown periods. The drawdown pipe will have an
orifice 4.00 inches (4') in diameter to control the drawdown rate. The basin volume between the
top of riser elevation of 162.60 and the normal pool elevation of 161.50 is the treatment volume and
equals 8,184 cubic feet, which exceeds the required minimum of 8,016 cubic feet. Flow from the
riser structure will be conveyed using a 60 foot long, 24" diameter corrugated aluminum pipe with
an upstream invert of 157.00 (at the riser) and a downstream invert of 156.40. The riser structure
shall have an anti-vortex/trash rack assembly provided that will extend from elevation 163.30
(above the maximum water elevation for the 25-year storm) to elevation 161.00 (6" below the
normal pool elevation). An emergency spillway will be provided to minimize the chance of
catastrophic failure of the dike. This spillway will be a 20 feet wide broad crested trapezoidal weir,
with 3:1 side slopes, and will have a weir elevation of 163.50. The top of dike elevation is 165.00.
Buoyancy Calculations
The outlet structures must be designed so as to be negatively buoyant with a minimum safety factor
of 1.1. The uplift is calculated using the outside dimensions of the structure and the weight is
calculated based on the volume and unit weight of the construction materials.
Basin 1
The inside dimension of the precast concrete structure is 5.0' square. The height is 130.80' (top of
riser, ignoring the weirs) minus 123.00 (invert out of 48" reinforced concrete pipe culvert), or 7.80.
With a 6-inch thick bottom slab and 6-inch thick walls, the outside dimensions are 6.0'x 6.0'x 8.30'.
The uplift is calculated based on the weight an equal volume of water displaced at 62.4 pounds per
cubic foot as follows:.
Uplift = (6.0'x 6.0'x 8.3) x 62.4 PCF
= 298.8 CF x 62.4 PCF
= 18,645 pounds
The weight of the structure is the displaced volume less the inside volume times the unit weight of
concrete. The unit weight of concrete is 150 pounds per cubic foot.
Weight = ((6.0'x 6.0'x 8.3? - (5.0'x 5.0'x 7.8')) x 150 PCF
_ (298.8 CF - 195.0 CF) x 150 PCF
= 15,570 pounds
Additional volume is to provide for ballast concrete. The structure will be deepened by 3.7 feet
(12.0' total depth) to provide this volume. The additional inside volume will be filled with concrete.
Calculations including the additional depth are as follows:
Uplift = (6.0'x 6.0'x 12.0') x 62.4 PCF
= 432.0 CF x 62.4 PCF
= 26,957 pounds
14 of 17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Weight = ((6.0'x 6.0'x 12.0 - (5.0'x 5.0'x 11.5 + (5.0'x 5.0'x 3.7')) x 150 PCF
_ (432.0 CF - 287.5 CF + 92.5) x 150 PCF
= 35,550 pounds (1.32 safety factor> 1.1 (OK))
Basin 2
The inside dimension of the corrugated aluminum pipe structure is 30 inches (2.50 in diameter (14
gauge with 3" x 1" corrugation). The height is 162.60' (top of riser) minus 157.00' (invert out of 24"
corrugated aluminum pipe culvert), or 5.6. The uplift is calculated based on the weight an equal
volume of water displaced at 62.4 pounds per cubic foot as follows:.
Uplift = [(II x (2.5?2)/4)x 5.61 x 150 PCF
= 27.5 CF x 62.4 PCF
= 1,716 pounds
The weight of the structure is negligible (approximately 64 pounds) and will be ignored.
A 4.0' x 4'0' x 2.0' cast-in-place concrete base will be provided to provide ballast. Calculations are
based on the submerged weight (in water) of concrete.
Weight = (4.0'x 4.0'x 2.0') x (150 - 62.4) PCF
= 32.0 CF x 87.6 PCF
= 2,803 pounds (1.63 safety factor>1.1 (OK))
Peak Flow Attenuation (Pre/Post Analysis)
The developed condition flows tributary to the basins was routed through the basins with the
following results:
Basin 1
Return Event Peak Flow In
(CFS) Peak Flow Out
(CFS) Time to Peak
(Out) (Min) Maximum Water Surface
Elevation (ft, MSL)
1-year 43.62 9.58 768 129.13
10-year 128.51 84.06 740 130.87
25-year 171.60 130.90 738 131.44
100-year 245.97 205.21 736 132.23
Basin 2
Return Event Peak Flow In
(CFS) Peak Flow Out
(CFS) Time to Peak
(Min) Maximum Water Surface
Elevation (ft, MSL)
1-year 2.67 .18 996 162.61
10-year 12.51 8.55 738 163.09
25-year 18.00 15.03 734 163.32
100-year 27.99 21.53 734 163.82
15 of 17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
Discharge Point 1 Developed Peak Discharge Rates
Description 1-year 10-year 25-year 100-year
Basin 1 Peak Flow Out (CFS) 9.58 84.06 130.90 205.21
Basin 1 Time to Peak (Out) (Min) 768 740 738 736
Not Tributary 2 Peak Flow (CFS) 0.99 2.95 3.96 5.71
Not Tributary 2 Time to Peak (Min) 766 758 758 756
Not Tributary 3 Peak Flow (CFS) 1.26 3.80 5.11 7.37
Not Tributary 3 Time to Peak (Min) 730 730 728 728
Discharge Point 1 Peak Flow* (CFS) 10.84 88.83 137.53 215.11
Discharge Point 1 Time to Peak (Min) 764 740 738 736
*Please note that the total peak discharge does not equal the sum of the peak discharges from the
subareas due to the difference in times to peak.
Discharge Point 2 Developed Peak Discharge Rates (CFS)
Description 1-year 10-year 25-year 100-year
Basin 2 Peak Flow Out (CFS) 2.67 8.55 17.00 26.66
Basin 2 Time to Peak (Out) (Min) 730 738 728 728
Not Tributary 1 Peak Flow (CFS) 2.96 8.85 11.83 16.97
Not Tributary 1 Time to Peak (Min) 724 722 722 722
Discharge Point 2 Peak Flow* (CFS) 2.96 11.76 21.64 36.13
Discharge Point 2 Time to Peak (Min) 724 734 730 724
*Please note that the total peak discharge does not equal the sum of the peak discharges from the
subareas due to the difference in times to peak.
The table below compares the predeveloped condition peak flows to the developed condition peak
flows, and indicates that the basins, as designed, meet the requirements of the ordinance.
Pre/Post Comparison
1-year Return Storm 10-year Return Storm
Discharge 1 Discharge 2 Discharge 1 Discharge 2
Predevelo ed 23.40 3.79 94.25 16.28
Developed 10.84 (OK) 2.96 (OK) 88.83 (OK) 11.76 (OK)
Drawdown
The basins must be designed to release the stored water quality volume over a period of two to five
days (48 to 120 hours). The average drawdown rate is calculated using the following formula:
Q = CA4 2gHo
where.
Q = flow in CFS
Co = coefficient of discharge (unitless)=0.60
A = orifice area in square feet
g = gravity (ft/sect) = 32.2 ft/sect
Ho = driving head (Maximum head / 3) in feet
16 of 17
April 12, 2011
Stormwater Management Plan
Fairfield Farms Subdivision
Phases Four, Five & Six
Broianco Corporation
The table below summarized the results of these calculations.
Basin Basin 1 Basin 2
Orifice Diameter in 3.375 1.375
Orifice Area (SF) 0.0668 0.0103
Water Quality Elevation Ew ft MSL 128.60 162.60
Permanent Pool Elevation (Epp)(ft, MSL) 127.00 161.50
Driving Head Ew Epp /3 ft 0.5333 0.3667
Average Orifice Flow CFS 0.2185 0.0319
Water Quality Volume (CF) 56,909 8,184
Drawdown Time Hrs 72.36 OK 71.31 OK
SUMMARY
The City of Fayetteville Stormwater Ordinance and Water Supply Watershed Management and
Protection Ordinance require that the peak stormwater discharge rates for High Density Projects
within the "non-Critical" Water Supply Watershed Protection Area be limited to the predeveloped
rate, and that the discharge from the runoff produced by a one-inch rainfall event be treated to
remove a minimum of 85 percent of the Total Suspended Solids conveyed. The primary treatment
system will be Wet Detention Basins in accordance with the Water Supply Watershed Management
and Protection Ordinance. The stored volume must be released over a period of at least two days,
but less than five days. The design and construction of the stormwater management facilities must
be in accordance with the requirements of the North Carolina Department of Environment and
Natural Resources, Division of Water Quality (NC DENR-DWQ) Stormwater Best Management
Practices Manual (BMP Manual).
The preceding calculations support that the stormwater management facilities, specifically wet
detention basins, are properly sized and configured to meet the requirements of stormwater peak
flow attenuation. The peak stormwater discharge for the entire site, in developed condition, is less
than the peak discharge for the predeveloped condition for the one-year and ten-year storm events,
as required by the ordinance.
The attached Construction Drawings indicate that the stormwater runoff from the Built-Upon Area is,
to the greatest extent possible, to be collected and treated before release. The basins are designed
to capture and treat the runoff from the one-inch of rainfall event. The storm drainage system
captures the runoff from approximately 95.5% of the maximum impervious area within the project,
and the wet detention basins are designed in accordance with the BMP Manual for 90% removal of
Total Suspended Solids (TSS). The resulting reduction in TSS for the site as a whole should be
approximately 86%, which meets the 85% requirement of the ordinance.
The stored volume from the first one inch of rainfall is released in approximately three days, which
meets the requirements of the ordinance to release the volume over two to five days.
Therefore, the Stormwater Management Plan for Fairfield Farms, Section Four, Five & Six, as
designed, meets the requirements set forth in the City of Fayetteville Stormwater Ordinance and
Water Supply Watershed Management and Protection Ordinance.
17 of 17
April 12, 2011
Designed By: BGB Date:
Checked By: JMKjr Date:
Company: MKR, Inc.
Project Name: Fairfield Farms Section 4-6
Project No.: 98-1702-01
Site Location (City/Town) Fayetteville, NC
Culvert Id. Basin 1 Out
Total Drainage Area (acres) 45.6
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe. If the tailwater depth is less
than half the outlet pipe diameter. it is classified nunimdun tailwater condition.
If it is greater than half the pipe diameter. it is classified maximum condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a miniiumn tailwater condition unless reliable flood stage elevations
shoe- otherwise-
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum/Maximum tailwater?
Discharge (cfs)
Velocity (ft./s)
48
21
Min TW (Fig. 8.06a)
84.1
11.8
Step 2. Based on the tallwater conditions deternuned in step 1. enter Figure
8.06a or Figure 8.06b, and determine d5o riprap size and minimum apron length
(L',). The d,. size is the median stone size in a well-graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape. and the
apron width at the outlet end from the same figure used in Step '.
Minimum TW
Maximum TW
Figure 8.06a Figure 8.06b
Riprap d50, (ft.) 12
User Input Data
Calculated Value
Reference Data
Minimum apron length, La (ft.) 26
Apron width at pipe outlet (ft.) 12
Apron shape
Apron width at outlet end (ft.) 30
Step 4. Determine the maximiun stone diameter:
d,, = 1.5 x dFo
Minimum TW
Max Stone Diameter, dmax (ft.) 18
Step 5. Deternune the apron thickness:
Apron thickness = 1.5 x dmax
Apron Thickness(ft.)
Minimum TW
27
12
4
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making it level for the 1111inIM M
length, Ld. from Figure 8.06a or FieLUe 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured- Keep the
apron as straight as possible and align it with the flow of the receiving stream.
Make any necessary. alignment bends near the pipe outlet so that the entrance
into the receiving stream is straight-
Some locations may require linung of the entire channel cross section to assure
stability.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessary (9ppen-r*x 8.05). Where overfalls exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 8068
13-Jun-11
13-Jun-11
Permit No.
(to be provided by DWQ)
©?,?'?
? F WA7F
OHO 9QG
t? r
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part III) must be printed, filled out and submitted along with all of the required information.
Project name Fairfield Farms Section 4, 5 & 6
Contact person James Kizer, Jr./ Blake Ball
Phone number 910-484-5191
Date Revised 14June2011
Drainage area number Basin 1
II. DESIGN INFORMATION
Site Characteristics
Drainage area 1,987,431 ft2
Impervious area, post-development 598,404 ft2
% impervious 30.11 %
Design rainfall depth 1.0 in
Storage Volume: Non-SA Waters
Minimum volume required 53,162 ft3 OK
Volume provided 56,909 ft3
OK, volume provided is equal to or in excess of volume required.
Storage Volume: SA Waters
1.5" runoff volume ft3
Pre-development 1-yr, 24-hr runoff ft3
Post-development 1-yr, 24-hr runoff ft3
Minimum volume required ft3
Volume provided ft3
Peak Flow Calculations
Is the pre/post control of the lyr 24hr storm peak flow required? Y (Y or N)
1-yr, 24-hr rainfall depth 3.0 in
Rational C, pre-development 0.18 (unitless)
Rational C, post-development 0.46 (unitless)
Rainfall intensity: 1-yr, 24-hr storm 0.13 in/hr OK
Pre-development 1-yr, 24-hr peak flow 1.07 ft3/sec
Post-development 1-yr, 24-hr peak flow 2.73 ft3/sec
Pre/Post 1-yr, 24-hr peak flow control 1.66 ft3/sec
Elevations
Temporary pool elevation 128.60 fmsl
Permanent pool elevation 127.00 fmsl
SHWT elevation (approx. at the perm. pool elevation) 127.20 fmsl
Top of 1 Oft vegetated shelf elevation 127.50 fmsl
Bottom of 1 Oft vegetated shelf elevation 126.50 fmsl
Sediment cleanout, top elevation (bottom of pond) 121.00 fmsl
Sediment cleanout, bottom elevation 120.00 fmsl
Sediment storage provided 1.00 ft
Is there additional volume stored above the state-required temp. pool? N (Y or N)
Elevation of the top of the additional volume fmsl
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Parts I. & II. Design Summary, Page 1 of 3
Permit No.
(to be provided by DWQ)
Surface Areas
Area, temporary pool
Area REQUIRED, permanent pool
SA/DA ratio
Area PROVIDED, permanent pool, Apsnn pW
Area, bottom of 1 Oft vegetated shelf, Abot shelf
Area, sediment cleanout, top elevation (bottom of pond), Abotyond
Volumes
Volume, temporary pool
Volume, permanent pool, Vpennyool
Volume, forebay (sum of forebays if more than one forebay)
Forebay % of permanent pool volume
SA/DA Table Data
Design TSS removal
Coastal SA/DA Table Used?
Mountain/Piedmont SA/DA Table Used?
SA/DA ratio
Average depth (used in SA/DA table):
Calculation option 1 used? (See Figure 10-2b)
Volume, permanent pool, Vpennyool
Area provided, permanent pool, Als-,ool
Average depth calculated
Average depth used in SA/DA, d.„ (Round to nearest 0.5ft)
Calculation option 2 used? (See Figure 10-2b)
Area provided, permanent pool, Als-,ool
Area, bottom of 1 Oft vegetated shelf, Abot shelf
Area, sediment cleanout, top elevation (bottom of pond), Abotyond
"Depth" (distance b/w bottom of 1 Oft shelf and top of sediment)
Average depth calculated
Average depth used in SA/DA, d.„ (Round to nearest 0.5ft)
Drawdown Calculations
Drawdown through orifice?
Diameter of orifice (if circular)
Area of orifice (if-non-circular)
Coefficient of discharge (CD)
Driving head (Ho)
Drawdown through weir?
Weir type
Coefficient of discharge (C.)
Length of weir (L)
Driving head (H)
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Storage volume discharge rate (through discharge orifice or weir)
Storage volume drawdown time
Additional Information
Vegetated side slopes
Vegetated shelf slope
Vegetated shelf width
Length of flowpath to width ratio
Length to width ratio
Trash rack for overflow & orifice?
Freeboard provided
Vegetated filter provided?
Recorded drainage easement provided?
Capures all runoff at ultimate build-out?
Drain mechanism for maintenance or emergencies is
Form SW401-Wet Detention Basin-Rev.8-9/17/09
39,005 ftz
29,811 ftz
1.50 (unitless)
32,799 ftz OK
29,078 ftz
13,445 ftz
56,909 ft3 OK
157,963 ft3
30,962 ft3
19.6% % OK
90 %
N (Y or N)
Y (Y or N)
1.50 (unitless)
N (Y or N)
157,963 ft3
32,799 ftz
ft Need 3 ft min.
ft
Y (Y or N)
32,799 ftz
29,078 ftz
13,445 ftz
5.50 ft
4.56 ft OK
4.5 ft OK
Y (Y or N)
3.38 in
inz
0.60 (unitless)
0.53 ft
N (Y or N)
(unitless)
(unitless)
ft
ft
1.07 ft3/sec
2.73 ft3/sec
0.22 ft3/sec
3.02 days OK, draws down in 2-5 days.
3 :1 OK
10 :1 OK
10.0 ft OK
3 :1 OK
3.0 :1 OK
Y (Y or N) OK
1.6 ft OK
N (Y or N) OK
Y (Y or N) OK
N (Y or N) Required to capture all runoff from the ultimate build-out
Drain Valve and portable pump
Parts I. & II. Design Summary, Page 2 of 3
Permit No.
(to be provided by DWQ)
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No.
JMK Jr. 26 & 27 of 27 1. Plans (1" 50' or larger) of the entire site showing:
Design at ultimate build-out,
Off-site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
JMK Jr. 23 of 27 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
Maintenance access,
Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
Basin cross-section,
Vegetation specification for planting shelf, and
Filter strip.
JMK Jr. 5 of 27 3. Section view of the wet detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and outlet structures.
JMK Jr. 5 of 27 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
JMK Jr. narrative pg 6 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
JMK Jr. 5 of 27 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
JMK Jr. narrative 7. The supporting calculations.
JMK Jr. attached 8. A copy of the signed and notarized operation and maintenance (0&M) agreement.
JMK Jr. attached 9. A copy of the deed restrictions (if required).
JMK Jr. attached 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County
soil maps are not an acceptable source of soils information.
Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III. Required Items Checklist, Page 3 of 3
Designed By: BGB Date:
Checked By: JMKjr Date:
Company: MKR, Inc.
Project Name: Fairfield Farms Section 4-6
Project No.: 98-1702-01
Site Location (City/Town) Fayetteville, NC
Culvert Id. Basin 2 Out
Total Drainage Area (acres) 6.13
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe. If the tailwater depth is less
than half the outlet pipe diameter. it is classified nunimdun tailwater condition.
If it is greater than half the pipe diameter. it is classified maxmi nun condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a mi'm'ni un tailwater condition unless reliable flood stage elevations
shoe- otherwise-
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum/Maximum tailwater?
Discharge (cfs)
Velocity (ft./s)
24
11
Min TW (Fig. 8.06a)
8.2
4.2
Step 2. Based on the tallwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d5o riprap size and minimum apron length
(L',). The d,. size is the median stone size itn a well-graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape. and the
apron width at the outlet end from the same figure used in Step Z.
Minimum TW
Maximum TW
Figure 8.06a Figure 8.06b
Riprap d50, (ft.) 0.42
User Input Data
Calculated Value
Reference Data
Minimum apron length, La (ft.) 13
Apron width at pipe outlet (ft.) 6
Apron shape
Apron width at outlet end (ft.) 15
Step 4. Determine the nlaximtuln stone diameter:
dl,%=1.5xdFo
Minimum TW
Max Stone Diameter, dmax (ft.) 0.63
Step 5. Determine the apron thickness:
Apron thickness = 1.5 x d..
Apron Thickness(ft.)
Minimum TW
0.945
6
2
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making, it level for the 11111111 UM
length, Ld. from Flowe 8_06a or Figure 8.06b. Extend the apron farther
downstrearn and along channel banks tintil stability is assured- Keep the
apron as straight as possible and align it with the flow of the receiving stream.
Make any necessary alignment bends near the pipe outlet so that the entrance
into the receiving stream is straight-
Some locations may require lining of the entire channel cross section to assure
stability.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessary (9ppV7(*a- 3.05). Waere overfalls exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 806.8
13-Jun-11
13-Jun-11
FAIRFIELD FARMS - Basin 1 Developed Condition
Project Summary
Title FAIRFIELD FARMS
Engineer M KR\bgb
Company Moorman, Kizer &
Reitzel, Inc.
Date 6/1/2010
Notes Basin 1 - Developed Condition
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Table of Contents
Fayetteville
Basin 1 (Developed)
Not Tributary 2
Not Tributary 3
Basin 1 (Developed)
Not Tributary 2
Not Tributary 3
Basin 1 (Developed)
Not Tributary 2
Not Tributary 3
User Notifications
Master Network Summary
TypeII 24hr (3.0 in)
Time-Depth Curve
Time-Depth Curve
Time-Depth Curve
Time-Depth Curve
TypeII 24hr (3.0 in)
Time of Concentration
Calculations
TypeII 24hr (3.0 in)
Time of Concentration
Calculations
TypeII 24hr (3.0 in)
Time of Concentration
Calculations
TypeII 24hr (3.0 in)
Runoff CN-Area
TypeII 24hr (3.0 in)
Runoff CN-Area
TypeII 24hr (3.0 in)
Runoff CN-Area
TypeII 24hr (3.0 in)
Unit Hydrograph
Summary
Unit Hydrograph
Summary
Unit Hydrograph
Summary
Unit Hydrograph
Summary
TypeII 24hr (3.0 in)
Unit Hydrograph
Summary
Unit Hydrograph
Summary
Unit Hydrograph
Summary
Unit Hydrograph
Summary
TypeII 24hr (3.0 in)
Unit Hydrograph
Summary
2
3
5
7
9
11
13
15
17
19
20
21
22
24
26
28
30
32
34
36
38
Table of Contents
Unit Hydrograph 40
Summary
Unit Hydrograph 42
Summary
Unit Hydrograph 44
Summary
Basin 1 TypeII 24hr (3.0 in)
Elevation-Area Volume 46
Curve
Volume Equations 47
Basin 1 Outlet TypeII 24hr (3.0 in)
Composite Rating Curve 48
Outlet Input Data 59
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: User Notifications
No user
User Notifications? notifications
generated.
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Master Network Summary
Catchments Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (min) (ft3/s)
(years) (ft')
Basin 1 (Developed) Developed 1-yr 1 179,685 730.000 43.62
Basin 1 (Developed) Developed 10-yr 10 507,402 728.000 128.51
Basin 1 (Developed) Developed 25-yr 25 677,107 728.000 171.60
Basin 1 (Developed) Developed 100-yr 100 975,903 728.000 245.97
Not Tributary 2 Developed 1-yr 1 8,765 766.000 0.99
Not Tributary 2 Developed 10-yr 10 24,752 758.000 2.95
Not Tributary 2 Developed 25-yr 25 33,030 758.000 3.96
Not Tributary 2 Developed 100-yr 100 47,606 756.000 5.71
Not Tributary 3 Developed 1-yr 1 5,163 730.000 1.26
Not Tributary 3 Developed 10-yr 10 14,908 730.000 3.80
Not Tributary 3 Developed 25-yr 25 19,991 728.000 5.11
Not Tributary 3 Developed 100-yr 100 28,969 728.000 7.37
Node Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (min) (ft3/s)
(years) (ft')
Out Developed 1-yr 1 190,298 768.000 10.84
Out Developed 10-yr 10 543,706 740.000 88.83
Out Developed 25-yr 25 726,762 738.000 137.53
Out Developed 100-yr 100 1,049,100 736.000 215.11
Pond Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (min) (ft3/s)
(years) (ft')
Maximum Maximum
Water Pond Storage
Surface (ft')
Elevation
(ft)
Basin 1 (IN) Developed 1- 1 179,685 730.000 43.62 (N/A) (N/A)

Basin 1 Developed 1- 1 176
370 768.000 9.58 129.13 237
622
(OUT) yr , ,
Basin 1 (IN) Developed 10- 10 507,402 728.000 128.51 (N/A) (N/A)

Basin 1 Developed 10- 10 504
046 740.000 84.06 130.87 312
601
(OUT) yr , ,
Basin 1 (IN) Developed 25- 25 677,107 728.000 171.60 (N/A) (N/A)

Basin 1
OUT Developed 25- 25 673,741 738.000 130.90 131.44 338,529
(
) yr
Basin 1 (IN) Developed 100 100 975,903 728.000 245.97 (N/A) (N/A)
-yr
Bentley Systems, Inc. Haestad Methods Solution
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Bentley PondPack V8i
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Page 3 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Master Network Summary
Pond Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (min) (ft3/s)
(years) (ft')
Maximum Maximum
Water Pond Storage
Surface (ft')
Elevation
(ft)
Basin 1 I Developed 100 I 100 I 972,525 I 736.000 I 205.21 I 132.23 I 375,835
(OUT) -yr
Bentley Systems, Inc. Haestad Methods Solution
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Page 4 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 1 years
Label: Fayetteville Storm Event: TypeII 24hr (3.0 in)
Time-Depth Curve: TypeII 24hr (3.0 in)
Label TypeII 24hr (3.0
in)
Start Time 0.000 min
Increment 6.000 min
End Time 1,440.000 min
Return Event 1 years
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
0.000 0.0 0.0 0.0 0.0 0.0
30.000 0.0 0.0 0.0 0.0 0.0
60.000 0.0 0.0 0.0 0.0 0.0
90.000 0.0 0.1 0.1 0.1 0.1
120.000 0.1 0.1 0.1 0.1 0.1
150.000 0.1 0.1 0.1 0.1 0.1
180.000 0.1 0.1 0.1 0.1 0.1
210.000 0.1 0.1 0.1 0.1 0.1
240.000 0.1 0.1 0.2 0.2 0.2
270.000 0.2 0.2 0.2 0.2 0.2
300.000 0.2 0.2 0.2 0.2 0.2
330.000 0.2 0.2 0.2 0.2 0.2
360.000 0.2 0.2 0.3 0.3 0.3
390.000 0.3 0.3 0.3 0.3 0.3
420.000 0.3 0.3 0.3 0.3 0.3
450.000 0.3 0.3 0.3 0.3 0.4
480.000 0.4 0.4 0.4 0.4 0.4
510.000 0.4 0.4 0.4 0.4 0.4
540.000 0.4 0.5 0.5 0.5 0.5
570.000 0.5 0.5 0.5 0.5 0.5
600.000 0.5 0.6 0.6 0.6 0.6
630.000 0.6 0.6 0.6 0.7 0.7
660.000 0.7 0.7 0.8 0.8 0.8
690.000 0.9 0.9 1.1 1.3 1.7
720.000 2.0 2.1 2.1 2.2 2.2
750.000 2.2 2.2 2.3 2.3 2.3
780.000 2.3 2.3 2.4 2.4 2.4
810.000 2.4 2.4 2.4 2.5 2.5
840.000 2.5 2.5 2.5 2.5 2.5
870.000 2.5 2.5 2.5 2.6 2.6
900.000 2.6 2.6 2.6 2.6 2.6
930.000 2.6 2.6 2.6 2.6 2.7
960.000 2.7 2.7 2.7 2.7 2.7
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 1 years
Label: Fayetteville
Storm Event: TypeII 24hr (3.0 in)
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
990.000 2.7 2.7 2.7 2.7 2.7
1,020.000 2.7 2.7 2.7 2.7 2.7
1,050.000 2.8 2.8 2.8 2.8 2.8
1,080.000 2.8 2.8 2.8 2.8 2.8
1,110.000 2.8 2.8 2.8 2.8 2.8
1,140.000 2.8 2.8 2.8 2.8 2.9
1,170.000 2.9 2.9 2.9 2.9 2.9
1,200.000 2.9 2.9 2.9 2.9 2.9
1,230.000 2.9 2.9 2.9 2.9 2.9
1,260.000 2.9 2.9 2.9 2.9 2.9
1,290.000 2.9 2.9 2.9 2.9 2.9
1,320.000 3.0 3.0 3.0 3.0 3.0
1,350.000 3.0 3.0 3.0 3.0 3.0
1,380.000 3.0 3.0 3.0 3.0 3.0
1,410.000 3.0 3.0 3.0 3.0 3.0
1,440.000 3.0 (N/A) (N/A) (N/A) (N/A)
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 10 years
Label: Fayetteville Storm Event: TypeII 24hr (5.5 in)
Time-Depth Curve: TypeII 24hr (5.5 in)
Label TypeII 24hr (5.5
in)
Start Time 0.000 min
Increment 6.000 min
End Time 1,440.000 min
Return Event 10 years
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
0.000 0.0 0.0 0.0 0.0 0.0
30.000 0.0 0.0 0.0 0.0 0.1
60.000 0.1 0.1 0.1 0.1 0.1
90.000 0.1 0.1 0.1 0.1 0.1
120.000 0.1 0.1 0.1 0.1 0.1
150.000 0.2 0.2 0.2 0.2 0.2
180.000 0.2 0.2 0.2 0.2 0.2
210.000 0.2 0.2 0.2 0.2 0.3
240.000 0.3 0.3 0.3 0.3 0.3
270.000 0.3 0.3 0.3 0.3 0.3
300.000 0.3 0.4 0.4 0.4 0.4
330.000 0.4 0.4 0.4 0.4 0.4
360.000 0.4 0.5 0.5 0.5 0.5
390.000 0.5 0.5 0.5 0.5 0.5
420.000 0.5 0.6 0.6 0.6 0.6
450.000 0.6 0.6 0.6 0.6 0.7
480.000 0.7 0.7 0.7 0.7 0.7
510.000 0.7 0.7 0.8 0.8 0.8
540.000 0.8 0.8 0.8 0.9 0.9
570.000 0.9 0.9 0.9 1.0 1.0
600.000 1.0 1.0 1.0 1.1 1.1
630.000 1.1 1.2 1.2 1.2 1.3
660.000 1.3 1.3 1.4 1.4 1.5
690.000 1.6 1.7 2.0 2.4 3.1
720.000 3.7 3.8 3.9 3.9 4.0
750.000 4.1 4.1 4.1 4.2 4.2
780.000 4.3 4.3 4.3 4.4 4.4
810.000 4.4 4.4 4.5 4.5 4.5
840.000 4.5 4.5 4.6 4.6 4.6
870.000 4.6 4.6 4.7 4.7 4.7
900.000 4.7 4.7 4.7 4.8 4.8
930.000 4.8 4.8 4.8 4.8 4.8
960.000 4.9 4.9 4.9 4.9 4.9
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 10 years
Label: Fayetteville Storm Event: TypeII 24hr (5.5 in)
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
990.000 4.9 4.9 4.9 5.0 5.0
1,020.000 5.0 5.0 5.0 5.0 5.0
1,050.000 5.0 5.0 5.1 5.1 5.1
1,080.000 5.1 5.1 5.1 5.1 5.1
1,110.000 5.1 5.1 5.2 5.2 5.2
1,140.000 5.2 5.2 5.2 5.2 5.2
1,170.000 5.2 5.2 5.2 5.2 5.2
1,200.000 5.3 5.3 5.3 5.3 5.3
1,230.000 5.3 5.3 5.3 5.3 5.3
1,260.000 5.3 5.3 5.3 5.3 5.4
1,290.000 5.4 5.4 5.4 5.4 5.4
1,320.000 5.4 5.4 5.4 5.4 5.4
1,350.000 5.4 5.4 5.4 5.4 5.5
1,380.000 5.5 5.5 5.5 5.5 5.5
1,410.000 5.5 5.5 5.5 5.5 5.5
1,440.000 5.5 (N/A) (N/A) (N/A) (N/A)
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 25 years
Label: Fayetteville Storm Event: TypeII 24hr (6.7 in)
Time-Depth Curve: TypeII 24hr (6.7 in)
Label TypeII 24hr (6.7
in)
Start Time 0.000 min
Increment 6.000 min
End Time 1,440.000 min
Return Event 25 years
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
0.000 0.0 0.0 0.0 0.0 0.0
30.000 0.0 0.0 0.0 0.1 0.1
60.000 0.1 0.1 0.1 0.1 0.1
90.000 0.1 0.1 0.1 0.1 0.1
120.000 0.1 0.2 0.2 0.2 0.2
150.000 0.2 0.2 0.2 0.2 0.2
180.000 0.2 0.2 0.2 0.3 0.3
210.000 0.3 0.3 0.3 0.3 0.3
240.000 0.3 0.3 0.3 0.3 0.4
270.000 0.4 0.4 0.4 0.4 0.4
300.000 0.4 0.4 0.4 0.5 0.5
330.000 0.5 0.5 0.5 0.5 0.5
360.000 0.5 0.5 0.6 0.6 0.6
390.000 0.6 0.6 0.6 0.6 0.6
420.000 0.7 0.7 0.7 0.7 0.7
450.000 0.7 0.7 0.8 0.8 0.8
480.000 0.8 0.8 0.8 0.8 0.9
510.000 0.9 0.9 0.9 0.9 1.0
540.000 1.0 1.0 1.0 1.0 1.1
570.000 1.1 1.1 1.1 1.2 1.2
600.000 1.2 1.2 1.3 1.3 1.3
630.000 1.4 1.4 1.4 1.5 1.5
660.000 1.6 1.6 1.7 1.7 1.8
690.000 1.9 2.1 2.4 2.9 3.8
720.000 4.4 4.6 4.7 4.8 4.9
750.000 4.9 5.0 5.0 5.1 5.1
780.000 5.2 5.2 5.2 5.3 5.3
810.000 5.3 5.4 5.4 5.4 5.5
840.000 5.5 5.5 5.5 5.6 5.6
870.000 5.6 5.6 5.6 5.7 5.7
900.000 5.7 5.7 5.7 5.8 5.8
930.000 5.8 5.8 5.8 5.9 5.9
960.000 5.9 5.9 5.9 5.9 5.9
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 25 years
Label: Fayetteville
Storm Event: TypeII 24hr (6.7 in)
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
990.000 6.0 6.0 6.0 6.0 6.0
1,020.000 6.0 6.0 6.1 6.1 6.1
1,050.000 6.1 6.1 6.1 6.1 6.1
1,080.000 6.2 6.2 6.2 6.2 6.2
1,110.000 6.2 6.2 6.2 6.3 6.3
1,140.000 6.3 6.3 6.3 6.3 6.3
1,170.000 6.3 6.3 6.3 6.4 6.4
1,200.000 6.4 6.4 6.4 6.4 6.4
1,230.000 6.4 6.4 6.4 6.4 6.4
1,260.000 6.5 6.5 6.5 6.5 6.5
1,290.000 6.5 6.5 6.5 6.5 6.5
1,320.000 6.5 6.5 6.6 6.6 6.6
1,350.000 6.6 6.6 6.6 6.6 6.6
1,380.000 6.6 6.6 6.6 6.6 6.6
1,410.000 6.7 6.7 6.7 6.7 6.7
1,440.000 6.7 (N/A) (N/A) (N/A) (N/A)
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve Return Event: 100 years
Label: Fayetteville Storm Event: TypeII 24hr (8.7 in)
Time-Depth Curve: TypeII 24hr (8.7 in)
Label TypeII 24hr (8.7
in)
Start Time 0.000 min
Increment 6.000 min
End Time 1,440.000 min
Return Event 100 years
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
0.000 0.0 0.0 0.0 0.0 0.0
30.000 0.0 0.1 0.1 0.1 0.1
60.000 0.1 0.1 0.1 0.1 0.1
90.000 0.1 0.1 0.2 0.2 0.2
120.000 0.2 0.2 0.2 0.2 0.2
150.000 0.2 0.3 0.3 0.3 0.3
180.000 0.3 0.3 0.3 0.3 0.3
210.000 0.4 0.4 0.4 0.4 0.4
240.000 0.4 0.4 0.4 0.5 0.5
270.000 0.5 0.5 0.5 0.5 0.5
300.000 0.5 0.6 0.6 0.6 0.6
330.000 0.6 0.6 0.6 0.7 0.7
360.000 0.7 0.7 0.7 0.7 0.8
390.000 0.8 0.8 0.8 0.8 0.8
420.000 0.9 0.9 0.9 0.9 0.9
450.000 0.9 1.0 1.0 1.0 1.0
480.000 1.0 1.1 1.1 1.1 1.1
510.000 1.1 1.2 1.2 1.2 1.2
540.000 1.3 1.3 1.3 1.4 1.4
570.000 1.4 1.4 1.5 1.5 1.5
600.000 1.6 1.6 1.6 1.7 1.7
630.000 1.8 1.8 1.9 1.9 2.0
660.000 2.0 2.1 2.2 2.3 2.4
690.000 2.5 2.7 3.1 3.7 4.9
720.000 5.7 5.9 6.1 6.2 6.3
750.000 6.4 6.4 6.5 6.6 6.6
780.000 6.7 6.7 6.8 6.8 6.9
810.000 6.9 7.0 7.0 7.0 7.1
840.000 7.1 7.1 7.2 7.2 7.2
870.000 7.3 7.3 7.3 7.3 7.4
900.000 7.4 7.4 7.5 7.5 7.5
930.000 7.5 7.5 7.6 7.6 7.6
960.000 7.6 7.6 7.7 7.7 7.7
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time-Depth Curve
Label: Fayetteville
Return Event: 100 years
Storm Event: TypeII 24hr (8.7 in)
CUMULATIVE RAINFALL (in)
Output Time Increment = 6.000 min
Time on left represents time for first value in each row.
Time Depth Depth Depth Depth Depth
(min) (in) (in) (in) (in) (in)
990.000 7.7 7.7 7.8 7.8 7.8
1,020.000 7.8 7.8 7.9 7.9 7.9
1,050.000 7.9 7.9 7.9 8.0 8.0
1,080.000 8.0 8.0 8.0 8.0 8.0
1,110.000 8.1 8.1 8.1 8.1 8.1
1,140.000 8.1 8.1 8.2 8.2 8.2
1,170.000 8.2 8.2 8.2 8.2 8.2
1,200.000 8.3 8.3 8.3 8.3 8.3
1,230.000 8.3 8.3 8.3 8.3 8.4
1,260.000 8.4 8.4 8.4 8.4 8.4
1,290.000 8.4 8.4 8.4 8.4 8.5
1,320.000 8.5 8.5 8.5 8.5 8.5
1,350.000 8.5 8.5 8.5 8.6 8.6
1,380.000 8.6 8.6 8.6 8.6 8.6
1,410.000 8.6 8.6 8.6 8.7 8.7
1,440.000 8.7 (N/A) (N/A) (N/A) (N/A)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time of Concentration Calculations Return Event: 10 years
Label: Basin 1 (Developed) Storm Event: TypeII 24hr (3.0 in)
Time of Concentration Results
Segment #1: User Defined Tc
Time of Concentration 13.800 min

Segment #2: SCS Lag
Hydraulic Length 308.00 ft
CN 72.000
Slope 0.017 ft/ft
Average Velocity 0.42 ft/s
Segment Time of 12.108 min
Concentration

Time of Concentration (Composite)
Time of Concentration 25
908 min
(Composite) .
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time of Concentration Calculations
Label: Basin 1 (Developed)
==== User Defined
Tc = Value entered by user
Where: Tc= Time of concentration, hours
==== SCS Lag
Tc = 0.000877 * (Lf**0.8) * ((1000/CN)-9)**0.7) * (Sf**-0.5)
Tc= Time of concentration, hours
Where: Lf= Flow length, feet
CN= SCS Curve Number
Sf= Slope, ft/ft
Return Event: 10 years
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time of Concentration Calculations
Label: Not Tributary 2
Time of Concentration Results
Segment #1: SCS Lag
Hydraulic Length 2,715.00 ft
C N 74.000
Slope 0.012 ft/ft
Average Velocity 0.58 ft/s
Segment Time of 77.694 min
Concentration

Time of Concentration (Composite)
Time of Concentration 77
694 min
(Composite) .
Return Event: 10 years
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time of Concentration Calculations Return Event: 10 years
Label: Not Tributary 2
==== SCS Lag
Tc = 0.000877 * (Lf**0.8) * ((1000/CN)-9)**0.7) * (Sf**-0.5)
Tc= Time of concentration, hours
Where: Lf= Flow length, feet
CN= SCS Curve Number
Sf= Slope, ft/ft
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time of Concentration Calculations
Label: Not Tributary 3
Time of Concentration Results
Segment #1: SCS Lag
Hydraulic Length 1,250.00 ft
CN 72.000
Slope 0.035 ft/ft
Average Velocity 0.81 ft/s
Segment Time of 25.577 min
Concentration

Time of Concentration (Composite)
Time of Concentration 25
577 min
(Composite) .
Return Event: 10 years
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Time of Concentration Calculations Return Event: 10 years
Label: Not Tributary 3
==== SCS Lag
Tc = 0.000877 * (Lf**0.8) * ((1000/CN)-9)**0.7) * (Sf**-0.5)
Tc= Time of concentration, hours
Where: Lf= Flow length, feet
CN= SCS Curve Number
Sf= Slope, ft/ft
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Runoff CN-Area Return Event: 10 years
Label: Basin 1 (Developed) Storm Event: TypeII 24hr (3.0 in)
Runoff Curve Number Data
Soil/Surface Description CN Area C UC Adjusted CN
(ft2) (%) (%)
Impervious Areas - Paved parking lots,
roofs, driveways, Streets and roads - Soil 98.000 598,404 0.0 0.0 98.000
A
Open space (Lawns,parks etc.) - Good 61.000 30
794 0.0 0.0 61.000
condition; grass cover > 75% - Soil B ,
Open space (Lawns,parks etc.) - Good 74.000 15
751 0.0 0.0 74.000
condition; grass cover > 75% - Soil C ,
Open space (Lawns,parks etc.) - Good 80
000 894 0
0 0
0 80
000
condition; grass cover > 75% - Soil D . . . .
Woods - good - Soil A 30.000 55,420 0.0 0.0 30.000
Woods - good - Soil B 55.000 28,563 0.0 0.0 55.000
Woods - good - Soil C 70.000 248,588 0.0 0.0 70.000
Open space (Lawns,parks etc.) - Good 39.000 125
774 0.0 0.0 39.000
condition; grass cover > 75% - Soil A ,
Open space (Lawns,parks etc.) - Good 74.000 817
904 0.0 0.0 74.000
condition; grass cover > 75% - Soil C ,
Open space (Lawns,parks etc.) - Good 80.000 65
338 0.0 0.0 80.000
condition; grass cover > 75% - Soil D ,
COMPOSITE AREA & WEIGHTED CN ---> (N/A) 1,987,430 (N/A) (N/A) 77.009
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Runoff CN-Area Return Event: 10 years
Label: Not Tributary 2 Storm Event: TypeII 24hr (3.0 in)
Runoff Curve Number Data
Soil/Surface Description CN Area C UC Adjusted CN
(ft2) (%) (%)
Impervious Areas - Paved parking lots,
roofs, driveways, Streets and roads - Soil 98.000 7,520 0.0 0.0 98.000
A
Open space (Lawns,parks etc.) - Good 74.000 50
797 0.0 0.0 74.000
condition; grass cover > 75% - Soil C ,
Open space (Lawns,parks etc.) - Good 80.000 19
705 0.0 0.0 80.000
condition; grass cover > 75% - Soil D ,
Open space (Lawns,parks etc.) - Good 74.000 16
863 0.0 0.0 74.000
condition; grass cover > 75% - Soil C ,
Open space (Lawns,parks etc.) - Good 80.000 2
064 0.0 0.0 80.000
condition; grass cover > 75% - Soil D ,
COMPOSITE AREA & WEIGHTED CN ---> (N/A) 96,949 (N/A) (N/A) 77.209
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Runoff CN-Area Return Event: 10 years
Label: Not Tributary 3 Storm Event: TypeII 24hr (3.0 in)
Runoff Curve Number Data
Soil/Surface Description CN Area C UC Adjusted CN
(ft2) (%) (%)
Impervious Areas - Paved parking lots,
roofs, driveways, Streets and roads - Soil 98.000 10,544 0.0 0.0 98.000
A
Open space (Lawns,parks etc.) - Good 61.000 727
9 0.0 0.0 61.000
condition; grass cover > 75% - Soil B ,
Open space (Lawns,parks etc.) - Good 74.000 1
951 0.0 0.0 74.000
condition; grass cover > 75% - Soil C ,
Open space (Lawns,parks etc.) - Good 80.000 11
479 0.0 0.0 80.000
condition; grass cover > 75% - Soil D ,
Open space (Lawns,parks etc.) - Good 61.000 7
700 0.0 0.0 61.000
condition; grass cover > 75% - Soil B ,
Open space (Lawns,parks etc.) - Good 74.000 9
892 0.0 0.0 74.000
condition; grass cover > 75% - Soil C ,
Open space (Lawns,parks etc.) - Good 80.000 8
944 0.0 0.0 80.000
condition; grass cover > 75% - Soil D ,
COMPOSITE AREA & WEIGHTED CN ---> (N/A) 60,237 (N/A) (N/A) 76.474
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 1 years
Label: Basin 1 (Developed) Storm Event: TypeII 24hr (3.0 in)
Storm Event TypeII 24hr(3.0
in)
Return Event 1 years
Duration 7,200.000 min
Depth 3.0 in
Time of Concentration 25
908 min
(Composite) .
Area (User Defined) 1,987,430 ft2
Computational Time 3.454 min
Increment
Time to Peak (Computed) 728.885 min
Flow (Peak, Computed) 44.01 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 730
000 min
Interpolated Output) .
Flow (Peak Interpolated 43.62 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 1,987,430 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 1
1 in
(Pervious) .
Runoff Volume (Pervious) 179,683 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 179,685 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
908 min
(Composite) .
Computational Time 3.454 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Basin 1 (Developed)
Return Event: 1 years
Storm Event: TypeII 24hr (3.0 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 119.72 ft3/s
Unit peak time, Tp 17.272 min
Unit receding limb, Tr 69.089 min
Total unit time, Tb 86.361 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
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Page 23 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 10 years
Label: Basin 1 (Developed) Storm Event: TypeII 24hr (5.5 in)
Storm Event TypeII 24hr(5.5
in)
Return Event 10 years
Duration 7,200.000 min
Depth 5.5 in
Time of Concentration 25
908 min
(Composite) .
Area (User Defined) 1,987,430 ft2
Computational Time 3.454 min
Increment
Time to Peak (Computed) 728.885 min
Flow (Peak, Computed) 129.83 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 728
000 min
Interpolated Output) ,
Flow (Peak Interpolated 128.51 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 1,987,430 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 3
1 in
(Pervious) .
Runoff Volume (Pervious) 507,393 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 507,402 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
908 min
(Composite) .
Computational Time 3.454 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Basin 1 (Developed)
Return Event: 10 years
Storm Event: TypeII 24hr (5.5 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 119.72 ft3/s
Unit peak time, Tp 17.272 min
Unit receding limb, Tr 69.089 min
Total unit time, Tb 86.361 min
Bentley Systems, Inc. Haestad Methods Solution
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 25 years
Label: Basin 1 (Developed) Storm Event: TypeII 24hr (6.7 in)
Storm Event TypeII 24hr(6.7
in)
Return Event 25 years
Duration 7,200.000 min
Depth 6.7 in
Time of Concentration 25
908 min
(Composite) .
Area (User Defined) 1,987,430 ft2
Computational Time 3.454 min
Increment
Time to Peak (Computed) 728.885 min
Flow (Peak, Computed) 173.10 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 728
000 min
Interpolated Output) ,
Flow (Peak Interpolated 171.60 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 1,987,430 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 4
1 in
(Pervious) .
Runoff Volume (Pervious) 677,093 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 677,107 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
908 min
(Composite) .
Computational Time 3.454 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Basin 1 (Developed)
Return Event: 25 years
Storm Event: TypeII 24hr (6.7 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 119.72 ft3/s
Unit peak time, Tp 17.272 min
Unit receding limb, Tr 69.089 min
Total unit time, Tb 86.361 min
Bentley Systems, Inc. Haestad Methods Solution
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 100 years
Label: Basin 1 (Developed) Storm Event: TypeII 24hr (8.7 in)
Storm Event TypeII 24hr(8.7
in)
Return Event 100 years
Duration 7,200.000 min
Depth 8.7 in
Time of Concentration 25
908 min
(Composite) .
Area (User Defined) 1,987,430 ft2
Computational Time 3.454 min
Increment
Time to Peak (Computed) 728.885 min
Flow (Peak, Computed) 247.72 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 728
000 min
Interpolated Output) ,
Flow (Peak Interpolated 245.97 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 1,987,430 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 5
9 in
(Pervious) .
Runoff Volume (Pervious) 975,882 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 975,903 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
908 min
(Composite) .
Computational Time 3.454 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Basin 1 (Developed)
Return Event: 100 years
Storm Event: TypeII 24hr (8.7 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 119.72 ft3/s
Unit peak time, Tp 17.272 min
Unit receding limb, Tr 69.089 min
Total unit time, Tb 86.361 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 1 years
Label: Not Tributary 2 Storm Event: TypeII 24hr (3.0 in)
Storm Event TypeII 24hr(3.0
in)
Return Event 1 years
Duration 7,200.000 min
Depth 3.0 in
Time of Concentration 77
694 min
(Composite) .
Area (User Defined) 96,949 ft2
Computational Time 10.359 min
Increment
Time to Peak (Computed) 766.578 min
Flow (Peak, Computed) 0.99 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 766
000 min
Interpolated Output) .
Flow (Peak Interpolated 0.99 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 96,949 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 1
1 in
(Pervious) .
Runoff Volume (Pervious) 8,765 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 8,765 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 77
694 min
(Composite) .
Computational Time 10.359 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 2
Return Event: 1 years
Storm Event: TypeII 24hr (3.0 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 1.95 ft3/s
Unit peak time, Tp 51.796 min
Unit receding limb, Tr 207.183 min
Total unit time, Tb 258.979 min
Bentley Systems, Inc. Haestad Methods Solution
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Page 31 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 10 years
Label: Not Tributary 2 Storm Event: TypeII 24hr (5.5 in)
Storm Event TypeII 24hr(5.5
in)
Return Event 10 years
Duration 7,200.000 min
Depth 5.5 in
Time of Concentration 77
694 min
(Composite) .
Area (User Defined) 96,949 ft2
Computational Time 10.359 min
Increment
Time to Peak (Computed) 756.219 min
Flow (Peak, Computed) 2.95 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 758
000 min
Interpolated Output) .
Flow (Peak Interpolated 2,95 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 96,949 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 3
1 in
(Pervious) .
Runoff Volume (Pervious) 24,751 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 24,752 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 77
694 min
(Composite) .
Computational Time 10.359 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 32 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 2
Return Event: 10 years
Storm Event: TypeII 24hr (5.5 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 1.95 ft3/s
Unit peak time, Tp 51.796 min
Unit receding limb, Tr 207.183 min
Total unit time, Tb 258.979 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 33 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 25 years
Label: Not Tributary 2 Storm Event: TypeII 24hr (6.7 in)
Storm Event TypeII 24hr(6.7
in)
Return Event 25 years
Duration 7,200.000 min
Depth 6.7 in
Time of Concentration 77
694 min
(Composite) .
Area (User Defined) 96,949 ft2
Computational Time 10.359 min
Increment
Time to Peak (Computed) 756.219 min
Flow (Peak, Computed) 3.96 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 758
000 min
Interpolated Output) .
Flow (Peak Interpolated 3.96 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 96,949 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 4
1 in
(Pervious) .
Runoff Volume (Pervious) 33,029 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 33,030 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 77
694 min
(Composite) .
Computational Time 10.359 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 34 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 2
Return Event: 25 years
Storm Event: TypeII 24hr (6.7 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 1.95 ft3/s
Unit peak time, Tp 51.796 min
Unit receding limb, Tr 207.183 min
Total unit time, Tb 258.979 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 35 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 100 years
Label: Not Tributary 2 Storm Event: TypeII 24hr (8.7 in)
Storm Event TypeII 24hr(8.7
in)
Return Event 100 years
Duration 7,200.000 min
Depth 8.7 in
Time of Concentration 77
694 min
(Composite) .
Area (User Defined) 96,949 ft2
Computational Time 10.359 min
Increment
Time to Peak (Computed) 756.219 min
Flow (Peak, Computed) 5.72 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 756
000 min
Interpolated Output) .
Flow (Peak Interpolated 5.71 ft3/s
Output)
Drainage Area
SCS CN (Composite) 77.000
Area (User Defined) 96,949 ft2
Maximum Retention
3
0 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 5
9 in
(Pervious) .
Runoff Volume (Pervious) 47,605 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 47,606 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 77
694 min
(Composite) .
Computational Time 10.359 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 36 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 2
Return Event: 100 years
Storm Event: TypeII 24hr (8.7 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 1.95 ft3/s
Unit peak time, Tp 51.796 min
Unit receding limb, Tr 207.183 min
Total unit time, Tb 258.979 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 37 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 1 years
Label: Not Tributary 3 Storm Event: TypeII 24hr (3.0 in)
Storm Event TypeII 24hr(3.0
in)
Return Event 1 years
Duration 7,200.000 min
Depth 3.0 in
Time of Concentration 25
577 min
(Composite) .
Area (User Defined) 60,237 ft2
Computational Time 3.410 min
Increment
Time to Peak (Computed) 729.806 min
Flow (Peak, Computed) 1.27 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 730
000 min
Interpolated Output) .
Flow (Peak Interpolated 1.26 ft3/s
Output)
Drainage Area
SCS CN (Composite) 76.000
Area (User Defined) 60,237 ft2
Maximum Retention
3
2 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 1
0 in
(Pervious) .
Runoff Volume (Pervious) 5,163 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 5,163 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
577 min
(Composite) .
Computational Time 3.410 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 38 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 3
Return Event: 1 years
Storm Event: TypeII 24hr (3.0 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 3.68 ft3/s
Unit peak time, Tp 17.052 min
Unit receding limb, Tr 68.206 min
Total unit time, Tb 85.258 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 39 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 10 years
Label: Not Tributary 3 Storm Event: TypeII 24hr (5.5 in)
Storm Event TypeII 24hr(5.5
in)
Return Event 10 years
Duration 7,200.000 min
Depth 5.5 in
Time of Concentration 25
577 min
(Composite) .
Area (User Defined) 60,237 ft2
Computational Time 3.410 min
Increment
Time to Peak (Computed) 729.806 min
Flow (Peak, Computed) 3.82 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 730
000 min
Interpolated Output) .
Flow (Peak Interpolated 3.80 ft3/s
Output)
Drainage Area
SCS CN (Composite) 76.000
Area (User Defined) 60,237 ft2
Maximum Retention
3
2 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 3
0 in
(Pervious) .
Runoff Volume (Pervious) 14,908 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 14,908 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
577 min
(Composite) .
Computational Time 3.410 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 40 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 3
Return Event: 10 years
Storm Event: TypeII 24hr (5.5 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 3.68 ft3/s
Unit peak time, Tp 17.052 min
Unit receding limb, Tr 68.206 min
Total unit time, Tb 85.258 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 41 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 25 years
Label: Not Tributary 3 Storm Event: TypeII 24hr (6.7 in)
Storm Event TypeII 24hr(6.7
in)
Return Event 25 years
Duration 7,200.000 min
Depth 6.7 in
Time of Concentration 25
577 min
(Composite) .
Area (User Defined) 60,237 ft2
Computational Time 3.410 min
Increment
Time to Peak (Computed) 729.806 min
Flow (Peak, Computed) 5.12 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 728
000 min
Interpolated Output) ,
Flow (Peak Interpolated 5.11 ft3/s
Output)
Drainage Area
SCS CN (Composite) 76.000
Area (User Defined) 60,237 ft2
Maximum Retention
3
2 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 4
0 in
(Pervious) .
Runoff Volume (Pervious) 19,991 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 19,991 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
577 min
(Composite) .
Computational Time 3.410 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 42 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 3
Return Event: 25 years
Storm Event: TypeII 24hr (6.7 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 3.68 ft3/s
Unit peak time, Tp 17.052 min
Unit receding limb, Tr 68.206 min
Total unit time, Tb 85.258 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 43 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary Return Event: 100 years
Label: Not Tributary 3 Storm Event: TypeII 24hr (8.7 in)
Storm Event TypeII 24hr(8.7
in)
Return Event 100 years
Duration 7,200.000 min
Depth 8.7 in
Time of Concentration 25
577 min
(Composite) .
Area (User Defined) 60,237 ft2
Computational Time 3.410 min
Increment
Time to Peak (Computed) 726.395 min
Flow (Peak, Computed) 7.38 ft3/s
Output Increment 2.000 min
Time to Flow (Peak 728
000 min
Interpolated Output) ,
Flow (Peak Interpolated 7.37 ft3/s
Output)
Drainage Area
SCS CN (Composite) 76.000
Area (User Defined) 60,237 ft2
Maximum Retention
3
2 in
(Pervious) .
Maximum Retention
0
6 in
(Pervious, 20 percent) .
Cumulative Runoff
Cumulative Runoff Depth 5
8 in
(Pervious) .
Runoff Volume (Pervious) 28,970 ft3
Hydrograph Volume (Area under Hydrograph curve)
Volume 28,969 ft3
SCS Unit Hydrograph Parameters
Time of Concentration 25
577 min
(Composite) .
Computational Time 3.410 min
Increment
Unit Hydrograph Shape 483.432
Factor
K Factor 0.749
Receding/Rising, Tr/Tp 1.670
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Cente r [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 44 of 65
Watertown, CT 06795 US A [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Unit Hydrograph Summary
Label: Not Tributary 3
Return Event: 100 years
Storm Event: TypeII 24hr (8.7 in)
SCS Unit Hydrograph Parameters
Unit peak, qp 3.68 ft3/s
Unit peak time, Tp 17.052 min
Unit receding limb, Tr 68.206 min
Total unit time, Tb 85.258 min
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 45 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Elevation-Area Volume Curve Return Event: 10 years
Label: Basin 1 Storm Event: TypeII 24hr (3.0 in)
Elevation Planimeter Area Al+A2+sqr Volume Volume (Total)
(ft) (ftz) (ftz) (A1*A2) (ft') (ft')
(ftz)
120.00 0.0 15,349 0 0 0
121.00 0.0 17,237 48,852 16,284 16,284
122.00 0.0 19,205 54,636 18,212 34,496
123.00 0.0 21,256 60,665 20,222 54,718
124.00 0.0 23,389 66,942 22,314 77,032
125.00 0.0 25,603 73,463 24,488 101,520
126.00 0.0 27,899 80,228 26,743 128,262
126.50 0.0 29,078 85,459 14,243 142,506
127.00 0.0 32,799 92,760 15,460 157,965
127.50 0.0 36,160 103,398 17,233 175,198
128.00 0.0 37,480 110,454 18,409 193,607
128.50 0.0 38,725 114,302 19,050 212,658
128.60 0.0 39,006 116,596 3,887 216,544
129.00 0.0 40,738 119,607 15,948 232,492
129.50 0.0 41,826 123,842 20,640 253,132
130.00 0.0 42,919 127,114 21,186 274,318
131.00 0.0 45,164 132,110 44,037 318,355
132.00 0.0 47,992 139,713 46,571 364,926
133.00 0.0 50,351 147,500 49,167 414,092
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Volume Equations Return Event: 10 years
Label: Basin 1
Storm Event: TypeII 24hr (3.0 in)
Pond Volume Equations
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2 - Eli) * (Areal + Area2 + sgr(Areal * Area2))
where: ELi, EL2 Lower and upper elevations of the increment
Areal, Area2 Areas computed for ELi, EL2, respectively
Volume Incremental volume between ELi and EL2
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 47 of 65
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet Storm Event: TypeII 24hr (3.0 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error
Elevation (ft3/s) (ft) (ft)
(ft)
120.00 0.00 (N/A) 0.00
120.10 0.00 (N/A) 0.00
120.20 0.00 (N/A) 0.00
120.30 0.00 (N/A) 0.00
120.40 0.00 (N/A) 0.00
120.50 0.00 (N/A) 0.00
120.60 0.00 (N/A) 0.00
120.70 0.00 (N/A) 0.00
120.80 0.00 (N/A) 0.00
120.90 0.00 (N/A) 0.00
121.00 0.00 (N/A) 0.00
121.10 0.00 (N/A) 0.00
121.20 0.00 (N/A) 0.00
121.30 0.00 (N/A) 0.00
121.40 0.00 (N/A) 0.00
121.50 0.00 (N/A) 0.00
121.60 0.00 (N/A) 0.00
121.70 0.00 (N/A) 0.00
121.80 0.00 (N/A) 0.00
121.90 0.00 (N/A) 0.00
122.00 0.00 (N/A) 0.00
122.10 0.00 (N/A) 0.00
122.20 0.00 (N/A) 0.00
122.30 0.00 (N/A) 0.00
122.40 0.00 (N/A) 0.00
122.50 0.00 (N/A) 0.00
122.60 0.00 (N/A) 0.00
122.70 0.00 (N/A) 0.00
122.80 0.00 (N/A) 0.00
122.90 0.00 (N/A) 0.00
123.00 0.00 (N/A) 0.00
123.10 0.00 (N/A) 0.00
123.20 0.00 (N/A) 0.00
123.30 0.00 (N/A) 0.00
123.40 0.00 (N/A) 0.00
123.50 0.00 (N/A) 0.00
123.60 0.00 (N/A) 0.00
123.70 0.00 (N/A) 0.00
123.80 0.00 (N/A) 0.00
123.90 0.00 (N/A) 0.00
124.00 0.00 (N/A) 0.00
124.10 0.00 (N/A) 0.00
124.20 0.00 (N/A) 0.00
Bentley Systems, Inc. Haestad Methods Solution Bentley Pond Pack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 48 of 65
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FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Water Surface
Elevation
(ft)
124.30
124.40
124.50
124.60
124.70
124.80
124.90
125.00
125.10
125.20
125.30
125.40
125.50
125.60
125.70
125.80
125.90
126.00
126.10
126.20
126.30
126.40
126.50
126.60
126.70
126.80
126.90
127.00
127.10
127.20
127.30
127.40
127.50
127.60
127.70
127.80
127.90
128.00
128.10
128.20
128.30
128.40
128.50
98_1702_01 Basin 1 May2010.ppc
6/9/2011
Storm Event: TypeII 24hr (3.0 in)
Flow Tailwater Elevation Convergence Error
(fta/S) (ft) (ft)
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.00 (N/A) 0.00
0.02 (N/A) 0.00
0.06 (N/A) 0.00
0.12 (N/A) 0.00
0.15 (N/A) 0.00
0.18 (N/A) 0.00
0.20 (N/A) 0.00
0.22 (N/A) 0.00
0.24 (N/A) 0.00
0.26 (N/A) 0.00
0.28 (N/A) 0.00
0.29 (N/A) 0.00
0.31 (N/A) 0.00
0.32 (N/A) 0.00
0.33 (N/A) 0.00
0.35 (N/A) 0.00
Bentley S ystems, Inc. Haestad Method s Solution
Center
27 Si emon Company Drive Suite 20 0 W
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Bentley PondPack V8i
[08.11.01.54]
Page 49 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Water Surface
Elevation
(ft)
128.60
128.70
128.80
128.90
129.00
129.10
129.20
129.30
129.40
129.50
129.60
129.70
129.80
129.90
130.00
130.10
130.20
130.30
130.40
130.50
130.60
130.70
130.80
130.90
131.00
131.10
131.20
131.30
131.40
131.50
131.60
131.70
131.80
131.90
132.00
132.10
132.20
132.30
132.40
132.50
132.60
132.70
132.80
98_1702_01 Basin 1 May2010.ppc
6/9/2011
Storm Event: TypeII 24hr (3.0 in)
Flow Tailwater Elevation Convergence Error
(fta/S) (ft) (ft)
0.36 (N/A) 0.00
1.13 (N/A) 0.00
2.53 (N/A) 0.00
4.34 (N/A) 0.00
6.48 (N/A) 0.00
8.90 (N/A) 0.00
11.59 (N/A) 0.00
14.48 (N/A) 0.00
17.62 (N/A) 0.00
20.95 (N/A) 0.00
24.49 (N/A) 0.00
28.18 (N/A) 0.00
32.05 (N/A) 0.00
36.09 (N/A) 0.00
40.24 (N/A) 0.00
44.60 (N/A) 0.00
49.11 (N/A) 0.00
53.74 (N/A) 0.00
58.46 (N/A) 0.00
63.34 (N/A) 0.00
68.37 (N/A) 0.00
73.54 (N/A) 0.00
78.81 (N/A) 0.00
86.09 (N/A) 0.00
95.06 (N/A) 0.00
105.22 (N/A) 0.00
114.35 (N/A) 0.00
121.50 (N/A) 0.00
127.82 (N/A) 0.00
135.41 (N/A) 0.00
144.03 (N/A) 0.00
153.27 (N/A) 0.00
162.19 (N/A) 0.00
171.42 (N/A) 0.00
181.15 (N/A) 0.00
191.41 (N/A) 0.00
202.24 (N/A) 0.00
213.64 (N/A) 0.00
225.63 (N/A) 0.00
238.23 (N/A) 0.00
251.42 (N/A) 0.00
265.23 (N/A) 0.00
279.66 (N/A) 0.00
Bentley S ystems, Inc. Haestad Method s Solution
Center
27 Si emon Company Drive Suite 20 0 W
Waterto wn, CT 06795 USA [phone]
Bentley PondPack V8i
[08.11.01.54]
Page 50 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Water Surface Flow Tailwater Elevation
Elevation (ft3/s) (ft)
(ft)
132.90 I 294.70 I (N/A)
133.00 310.36 (N/A)
Contributing Structures
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
Storm Event: TypeII 24hr (3.0 in)
Convergence Error
(ft)
0.00
0.00
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 51 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Storm Event: TypeII 24hr (3.0 in)
Bentley PondPack V8i
[08.11.01.54]
Page 52 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Storm Event: TypeII 24hr (3.0 in)
Bentley PondPack V8i
[08.11.01.54]
Page 53 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
Bentley Systems, Inc. Haestad Methods Solution
98_1702_01 Basin 1 May2010.ppc Center
6/9/2011 27 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
Storm Event: TypeII 24hr (3.0 in)
Bentley PondPack V8i
[08.11.01.54]
Page 54 of 65
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
(no Q: Weir - 4,Weir - 3,Weir - 2,Weir
- 1,Riser -
1, Drawdown,Culvert,Spi l lway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 55 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Drawdown,Culvert (no Q: Weir -
4,Weir - 3,Weir - 2,Weir - 1,Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 56 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Drawdown,Culvert (no Q: Riser -
1,Spillway)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert (no Q:
Spillway)
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 57 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Composite Rating Curve Return Event: 1 years
Label: Basin 1 Outlet
Composite Outflow Summary
Contributing Structures
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert (no Q:
Spillwa y)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert (no Q:
Spillwa y)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert (no Q:
Spillwa y)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert (no Q:
Spillwa y)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert (no Q:
Spillwa y)
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1,Riser - 1,Drawdown,Culvert,Spillway
Weir - 4,Weir - 3,Weir - 2,Weir -
1.Riser - 1.Drawdown.Culvert.SDillwav
Storm Event: TypeII 24hr (3.0 in)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 58 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Outlet Input Data Return Event: 10 years
Label: Basin 1 Outlet Storm Event: TypeII 24hr (3.0 in)
Requested Pond Water Surface Elevations
Minimum (Headwater) 120.00 ft
Increment (Headwater) 0.10 ft
Maximum (Headwater) 133.00 ft
Outlet Connectivity
Structure Type Outlet ID Direction Outfall E1 E2
(ft) (ft)
Rectangular Weir Weir - 4 Forward Culvert 128.60 133.00
Rectangular Weir Weir - 3 Forward Culvert 128.60 133.00
Rectangular Weir Weir - 2 Forward Culvert 128.60 133.00
Rectangular Weir Weir - 1 Forward Culvert 128.60 133.00
Inlet Box Riser - 1 Forward Culvert 130.80 133.00
Orifice-Circular Drawdown Forward Culvert 127.00 133.00
Culvert-Circular Culvert Forward TW 123.00 133.00
Irregular Weir Spillway Forward TW 131.40 133.00
Tailwater Settings Tailwater (N/A) (N/A)
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 59 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Outlet Input Data
Label: Basin 1 Outlet
Return Event: 10 years
Storm Event: TypeII 24hr (3.0 in)
Structure ID: Riser - 1
Structure Type: Inlet Box
Number of Openings 1
Elevation 130.80 ft
Orifice Area 25.0 ft2
Orifice Coefficient 0.600
Weir Length 20.00 ft
Weir Coefficient 3.00 (ft^0.5)/s
K Reverse 1.000
Manning's n 0.000
Kev, Charged Riser 0.000
Weir Submergence True
Orifice H to crest False
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 60 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Outlet Input Data Return Event: 10 years
Label: Basin 1 Outlet Storm Event: TypeII 24hr (3.0 in)
Structure ID: Culvert
Structure Type: Culvert-Circular
Number of Barrels 1
Diameter 48.0 in
Length 64.00 ft
Length (Computed Barrel) 64.00 ft
Slope (Computed) 0.010 ft/ft

Outlet Control Data
Manning's n 0.013
Ke 0.500
Kb 0.005
Kr 0.500
Convergence Tolerance 0.00 ft

Inlet Control Data
Equation Form Form 1
K 0.0098
M 2.0000
C 0.0398
Y 0.6700
T1 ratio (HW/D) 1.155
T2 ratio (HW/D) 1.302
Slope Correction Factor -0.500
Use unsubmerged inlet control 0 equation below T1
elevation.
Use submerged inlet control 0 equation above T2
elevation
In transition zone between unsubmerged and submerged
inlet control,
interpolate between flows at T1 & T2...
T1 Elevation 127.62 ft T1 Flow 87.96 ft3/s
T2 Elevation 128.21 ft T2 Flow 100.53 ft3/s
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 61 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Outlet Input Data Return Event: 10 years
Label: Basin 1 Outlet Storm Event: TypeII 24hr (3.0 in)
Structure ID: Drawdown
Structure Type: Orifice-Circular
Number of Openings 1
Elevation 127.00 ft
Orifice Diameter 3.4 in
Orifice Coefficient 0.600
Structure ID: Spillway
Structure Type: Irregular Weir
Station Elevation
(ft) (ft)
0.00 133.00
4.80 131.40
24.80 131.40
29.60 133.00
Lowest Elevation 131.40 ft
Weir Coefficient 3.00 (ft^0.5)/s
Structure ID: Weir - 1
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 128.60 ft
Weir Length 2.00 ft
Weir Coefficient 3.00 (ft^0.5)/s

Structure ID: Weir -2
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 128.60 ft
Weir Length 2.00 ft
Weir Coefficient 3.00 (ft^0.5)/s

Structure ID: Weir -3
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 128.60 ft
Weir Length 2.00 ft
Weir Coefficient 3.00 (ft^0.5)/s

Structure ID: Weir -4
Structure Type: Rectangular Weir
Number of Openings 1
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 62 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Subsection: Outlet Input Data
Label: Basin 1 Outlet
Return Event: 10 years
Storm Event: TypeII 24hr (3.0 in)
Structure ID: Weir -4
Structure Type: Rectangular Weir
Elevation 128.60 ft
Weir Length 2.00 ft
Weir Coefficient 3.00 (ft^0.5)/s

Structure ID: TW
Structure Type: TW Setup, DS Channel
Tailwater Type Free Outfall

Convergence Tolerances
Maximum Iterations 30
Tailwater Tolerance 0
01 ft
(Minimum) .
Tailwater Tolerance 0
50 ft
(Maximum) .
Headwater Tolerance 0
01 ft
(Minimum) .
Headwater Tolerance 0
50 ft
(Maximum) .
Flow Tolerance (Minimum) 0.001 ft3/s
Flow Tolerance (Maximum) 10.000 ft3/s
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 63 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Index
B
Basin 1 (Developed) (Runoff CN-Area, 10 years)... 19
Basin 1 (Developed) (Time of Concentration Calculations, 10 years)... 13, 14
Basin 1 (Developed) (Unit Hydrograph Summary, 1 years) ...22, 23
Basin 1 (Developed) (Unit Hydrograph Summary, 10 years) ...24, 25
Basin 1 (Developed) (Unit Hydrograph Summary, 100 years) ...28, 29
Basin 1 (Developed) (Unit Hydrograph Summary, 25 years) ...26, 27
Basin 1 (Elevation-Area Volume Curve, 10 years) ...46
Basin 1 (Volume Equations, 10 years) ...47
Basin 1 Outlet (Composite Rating Curve, 1 years) ...48, 49, 50, 51, 52, 53, 54, 55,
56, 57,58
Basin 1 Outlet (Outlet Input Data, 10 years)... 59, 60, 61, 62, 63
F
Fayetteville (Time-Depth Curve, 1 years) ...5, 5,6
Fayetteville (Time-Depth Curve, 10 years) ...7, 7,8
Fayetteville (Time-Depth Curve, 100 years)... 11, 12
Fayetteville (Time-Depth Curve, 25 years) ...9, 10
M
Master Network Summary ...3, 3,4
N
Not Tributary 2 (Runoff CN-Area, 10 years) ...20
Not Tributary 2 (Time of Concentration Calculations, 10 years)... 15, 16
Not Tributary 2 (Unit Hydrograph Summary, 1 years) ...30, 31
Not Tributary 2 (Unit Hydrograph Summary, 10 years) ...32, 33
Not Tributary 2 (Unit Hydrograph Summary, 100 years) ...36, 37
Not Tributary 2 (Unit Hydrograph Summary, 25 years)... 34, 35
Not Tributary 3 (Runoff CN-Area, 10 years) ...21
Not Tributary 3 (Time of Concentration Calculations, 10 years)... 17, 18
Not Tributary 3 (Unit Hydrograph Summary, 1 years) ...38, 39
Not Tributary 3 (Unit Hydrograph Summary, 10 years) ...40, 40,41
Not Tributary 3 (Unit Hydrograph Summary, 100 years) ...44, 44,45
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 64 of 65
Watertown, CT 06795 USA [phone]
FAIRFIELD FARMS - Basin 1 Developed Condition
Not Tributary 3 (Unit Hydrograph Summary, 25 years) ...42, 42,43
U
User Notifications ...2
Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i
98_1702_01 Basin 1 May2010.ppc Center [08.11.01.54]
6/9/2011 27 Siemon Company Drive Suite 200 W Page 65 of 65
Watertown, CT 06795 USA [phone]
Designed By: BGB Date:
Checked By: JMKjr Date:
Company: MKR, Inc.
Project Name: Fairfield Farms Section 4-6
Project No.: 98-1702-01
Site Location (City/Town) Fayetteville, NC
Culvert Id. OF1
Total Drainage Area (acres) 45.6
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe. If the tailwater depth is less
than half the outlet pipe diameter. it is classified nunimdun tailwater condition.
If it is greater than half the pipe diameter. it is classified maxmi nun condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a mi'm'ni un tailwater condition unless reliable flood stage elevations
shoe- otherwise-
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum/Maximum tailwater?
Discharge (cfs)
Velocity (ft./s)
48
21
Min TW (Fig. 8.06a)
110.4
13.5
Step 2. Based on the tallwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d5o riprap size and minimum apron length
(L',). The d,. size is the median stone size itn a well-graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape. and the
apron width at the outlet end from the same figure used in Step Z.
Minimum TW
Maximum TW
Figure 8.06a Figure 8.06b
Riprap d50, (ft.) 1.25
User Input Data
Calculated Value
Reference Data
Minimum apron length, La (ft.) 26
Apron width at pipe outlet (ft.) 12
Apron shape
Apron width at outlet end (ft.) 30
Step 4. Determine the nlaximtuln stone diameter:
dl,%=1.5xdFo
Minimum TW
Max Stone Diameter, dmax (ft.) 1.875
Step 5. Determine the apron thickness:
Apron thickness = 1.5 x d..
Apron Thickness(ft.)
Minimum TW
2.8125
12
4
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making, it level for the 11111111 UM
length, Ld. from Flowe 8.06a or Figure 8.06b. Extend the apron farther
downstrearn and along channel banks tintil stability is assured- Keep the
apron as straight as possible and align it with the flow of the receiving stream.
Make any necessary alignment bends near the pipe outlet so that the entrance
into the receiving stream is straight-
Some locations may require lining of the entire channel cross section to assure
stability.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessary (9ppV7(*a- 3.05). Waere overfalls exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 806.8
13-Jun-11
13-Jun-11
Designed By: BGB Date:
Checked By: JMKjr Date:
Company: MKR, Inc.
Project Name: Fairfield Farms Section 4-6
Project No.: 98-1702-01
Site Location (City/Town) Fayetteville, NC
Culvert Id. OF2
Total Drainage Area (acres) 6.13
Step 1. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe. If the tailwater depth is less
than half the outlet pipe diameter. it is classified nunimdun tailwater condition.
If it is greater than half the pipe diameter. it is classified maxmi nun condition.
Pipes that outlet onto wide flat areas with no defined channel are assumed
to have a mi'm'ni un tailwater condition unless reliable flood stage elevations
shoe- otherwise-
Outlet pipe diameter, Do (in.)
Tailwater depth (in.)
Minimum/Maximum tailwater?
Discharge (cfs)
Velocity (ft./s)
24
11
Min TW (Fig. 8.06a)
11.7
12.2
Step 2. Based on the tallwater conditions determined in step 1. enter Figure
8.06a or Figure 8.06b, and determine d5o riprap size and minimum apron length
(L',). The d,. size is the median stone size itn a well-graded riprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape. and the
apron width at the outlet end from the same figure used in Step Z.
Minimum TW
Maximum TW
Figure 8.06a Figure 8.06b
Riprap d50, (ft.) 0.75
User Input Data
Calculated Value
Reference Data
Minimum apron length, La (ft.) 13
Apron width at pipe outlet (ft.) 6
Apron shape
Apron width at outlet end (ft.) 15
Step 4. Determine the nlaximtuln stone diameter:
dl,%=1.5xdFo
Minimum TW
Max Stone Diameter, dmax (ft.) 1.125
Step 5. Determine the apron thickness:
Apron thickness = 1.5 x d..
Apron Thickness(ft.)
Minimum TW
1.6875
6
2
Maximum TW
0
Maximum TW
0
Step 6. Fit the riprap apron to the site by making, it level for the 11111111 UM
length, Ld. from Flowe 8.06a or Figure 8.06b. Extend the apron farther
downstrearn and along channel banks tintil stability is assured- Keep the
apron as straight as possible and align it with the flow of the receiving stream.
Make any necessary alignment bends near the pipe outlet so that the entrance
into the receiving stream is straight-
Some locations may require lining of the entire channel cross section to assure
stability.
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessary (9ppV7(*a- 3.05). Waere overfalls exist at
pipe outlets or flows are excessive, a plunge pool should be considered, see
page 806.8
13-Jun-11
13-Jun-11