20081348 Ver 1_More Info Received_20081016

Mitchell Environmental, P.A.
October 16, 2008
aq o8-134$
Mrs. Lia M. Gilleski & Mr. Joseph Gyamfi
US DWQ - 401 WQC Unit
2321 Crabtree Boulevard, Suite 250
Raleigh, North Carolina 27604
Re: Cedar Chest Subdivision (Wake County - Neuse River Basin)
Request for more information
Dear Mrs. Gilleski & Mr. Gyamfi,
As discussed in the meeting on 10/14/2008 we have enclosed all of the information.
• The 10' wide easement consists of a 6' wide stone channel and 2' of easement space on
either side. 10' wide is the narrowest easement that will allow any equipment to access
the area. There is a cross section of the channel in trapezoidal design on the plans.
• The rain garden has been updated to the new specifications. Included is an additional
plant species and removal of mulch to the design. A detailed rain gutter specification has
been included as well as calculations for the cistern and by-pass. The O& M agreement
has been updated and the original signed copies are enclosed.
• Level Spreader # 2 has been updated to be located closer to the riparian 50' buffer line.
The reason the bioretention cell supplement worksheet has been filled out by hand is that
the excel worksheet is only for a 1 year storm and is protected so cannot be filled out for
a 2 year storm.
• The bare soil below level spreader # 3 as discussed will have sod up to the edge of the
stream.
Please feel free to call me if you have any questions or concerns regarding the attached PCN
application or if you need any additional information. Thank you.
Sincerely,
Rd"o FJ6-
Robin Eddy
Scott Mitchell
1;2 pm
VJU
J C 12008
i Et?k, tjJi ER („UPL'.[
\?dam E , ?t? A"!C STaRtA?n, WI ER Br7A+?CH
PO Box 341 Fuquay-Varina, North Carolina 27526
Office: 919-557-4682 Fax: [phone]

n a emm
PROGRAM
September 30, 2008
Leonard Woodall
Toxey Drive, LLC
702 Oberlin Road, Ste 410
Raleigh, NC 27605 Expiration of Acceptance: July 2, 2009
Project: Cedar Chest Subdivision County: Wake
The purpose of this letter is to notify you that the North Carolina Ecosystem Enhancement Program (NCEEP) is willing to accept
payment for impacts associated with the above referenced project. Please note that this decision does not assure that the payment will
be approved by the permit issuing agencies as mitigation for project impacts. It is the responsibility of the applicant to contact these
agencies to determine if payment to the NCEEP will be approved.
This acceptance is valid for nine months from the date of this letter and is not transferable. If we have not received a copy of the
issued 404 Permit/401 Certification/CAMA permit within this time frame, this acceptance will expire. It is the applicant's
responsibility to send copies of the permits to NCEEP. Once NCEEP receives a copy of the permit(s) an invoice will be issued based
on the required mitigation in that permit and payment must be made prior to conducting the authorized work. The amount of the In
Lieu Fee to be paid to NCEEP by an applicant is calculated based upon the Fee Schedule and policies listed at www.nceep.net.
Based on the information supplied by you the impacts that may require compensatory mitigation are summarized in the following
table.
River
Basin CU
Location Stream (feet) Wetlands (acres) Buffer I
(Sq. Ft.) Buffer It
(Sq. Ft.)
Cold Cool Warm Riparian Non-Riparian Coastal Marsh
Impacts Neuse 03020201 0 0 0 0 0 0 0 1,900
Credits Neuse 03020201 0 0 0 0 0 0 0 2,850
Upon receipt of payment, EEP will take responsibility for providing the compensatory mitigation. If the regulatory agencies require
mitigation credits greater than indicated above, and the applicant wants NCEEP to be responsible for the additional mitigation, the
applicant will need to submit a mitigation request to NCEEP for approval prior to permit issuance. The mitigation will be performed
in accordance with the Memorandum of Understanding between the N. C. Department of Environment and Natural Resources and the
U. S. Army Corps of Engineers dated November 4, 1998.
If you have any questions or need additional information, please contact Valerie Mitchener at [phone].
Sincerely,
William 7GHmore, PE
Director.
cc: Cyndi Karoly, NCDWQ Wetlands/401 Unit
Jamie Shern, USACE-Raleigh
Eric Kulz, NCDWQ-Raleigh
Robin Eddy, agent
File
Rt?-StoYGl?L?F?... l?;? ,l,K?... PYo&4e trtl?j 0" St7a&
&\-
W01WR
North Carolina Ecosystem Enhancement Program, 1652 Mail Service Center, Raleigh, NC 27699-1652 / 919-715-0476 / www.nceep.net

2B .0250 (Randleman Rules and Water Supply Buffer Requirements), or other (please
identify )? Yes ® No ?
2. If "yes", identify the square feet and acreage of impact to each zone of the riparian buffers.
If buffer mitigation is required calculate the required amount of mitigation by applying the
buffer multipliers.
Zone* Impact
(square feet) Multiplier Required
Mitigation
1 8,293 3 (2 for Catawba)
2 5,323 1.5 2,738
Total 13,616 2,738
* Zone 1 extends out 30 feet perpendicular from the top of the near bank of channel; Zone 2 extends an
additional 20 feet from the edge of Zone 1.
3. If buffer mitigation is required, please discuss what type of mitigation is proposed (i.e.,
Donation of Property, Riparian Buffer Restoration / Enhancement, or Payment into the
Riparian Buffer Restoration Fund). Please attach all appropriate information as identified
within 15A NCAC 2B .0242 or .0244, or .0260. None proposed
XI. Stormwater (required by DWQ)
Describe impervious acreage (existing and proposed) versus total acreage on the site. Discuss
stormwater controls proposed in order to protect surface waters and wetlands downstream from
the property. If percent impervious surface exceeds 20%, please provide calculations
demonstrating total proposed impervious level. The site total is 4.79 acres. The existing
impervious areas are 0.28 Ac. The proposed impervious areas are 1.29 Ac. 27%. Storage
chambers stormtrap system) and level spreaders designed per DWQ guidelines will be utilized.
See stormwater plan (pg. 7) for full details for calculations on nitrogen and bpydown payment.
XII. Sewage Disposal (required by DWQ)
Clearly detail the ultimate treatment methods and disposition (non-discharge or discharge) of
wastewater generated from the proposed project, or available capacity of the subject facility.
The site will utilize the local municipal sewer & water.
XIII. Violations (required by DWQ)
Is this site in violation of DWQ Wetland Rules (15A NCAC 2H.0500) or any Buffer Rules?
Yes ? No
Is this an after-the-fact permit application? Yes ? No
Page 12 of 13

4n ameme i,
PROGRAM
September 30, 2008
Leonard Woodall
Toxey Drive, LLC
702 Oberlin Road, Ste 410
Raleigh, NC 27605 Expiration of Acceptance: July 2, 2009
Project: Cedar Chest Subdivision County: Wake
The purpose of this letter is to notify you that the North Carolina Ecosystem Enhancement Program (NCEEP) is willing to accept
payment for impacts associated with the above referenced project. Please note that this decision does not assure that the payment will
be approved by the permit issuing agencies as mitigation for project impacts. It is the responsibility of the applicant to contact these
agencies to determine if payment to the NCEEP will be approved.
This acceptance is valid for nine months from the date of this letter and is not transferable. If we have not received a copy of the
issued 404 Permit/401 Certification/CAMA permit within this time frame, this acceptance will expire. It is the applicant's
responsibility to send copies of the permits to NCEEP. Once NCEEP receives a copy of the permit(s) an invoice will be issued based
on the required mitigation in that permit and payment must be made prior to conducting the authorized work. The amount of the In
Lieu Fee to be paid to NCEEP by an applicant is calculated based upon the Fee Schedule and policies listed at www.nceep.net.
Based on the information supplied by you the impacts that may require compensatory mitigation are summarized in the following
table.
River
Basin CU
Location Stream (feet) Wetlands (acres) Buffer I
(Sq. Ft.) Buffer 11
(Sq. Ft.)
Cold Cool Warm Riparian Non-Riparian Coastal Marsh
Impacts Neuse 03020201 0 0 0 0 0 0 0 1,900
Credits Neuse 03020201 0 0 0 0 0 0 0 21850
Upon receipt of payment, EEP will take responsibility for providing the compensatory mitigation. If the regulatory agencies require
mitigation credits greater than indicated above, and the applicant wants NCEEP to be responsible for the additional mitigation, the
applicant will need to submit a mitigation request to NCEEP for approval prior to permit issuance. The mitigation will be performed
in accordance with the Memorandum of Understanding between the N. C. Department of Environment and Natural Resources and the
U. S. Army Corps of Engineers dated November 4, 1998.
If you have any questions or need additional information, please contact Valerie Mitchener at [phone].
Sincerely,
William 7Gilmore, PE
Director,
cc: Cyndi Karoly, NCDWQ Wetlands/401 Unit
Jamie Shern, USACE-Raleigh
Eric Kulz, NCDWQ-Raleigh
Robin Eddy, agent
File
K"tDr&iL5... El2Gtaf'GCU?... PYDtt'&ing 0" Stag
-6? 6"
ASIA&
North Carolina Ecosystem Enhancement Program, 1652 Mail Service Center, Raleigh, NC 27699-1652 / 919-715-0476 1 www.nceep.net

2B .0250 (Randleman Rules and Water Supply Buffer Requirements), or other (please
identify _ )? Yes ® No ?
2. If "yes", identify the square feet and acreage of impact to each zone of the riparian buffers.
If buffer mitigation is required calculate the required amount of mitigation by applying the
buffer multipliers.
Zone's Impact
(square feet) Multiplier Required
Mitigation
1 8,293 3 (2 for Catawba)
2 5,323 1.5 2,738
Total 13,616 2,73 8
* Zone 1 extends out 30 feet perpendicular from the top of the near bank of channel; Zone 2 extends an
additional 20 feet from the edge of Zone 1.
3. If buffer mitigation is required, please discuss what type of mitigation is proposed (i.e.,
Donation of Property, Riparian Buffer Restoration / Enhancement, or Payment into the
Riparian Buffer Restoration Fund). Please attach all appropriate information as identified
within 15A NCAC 2B .0242 or .0244, or .0260. None proposed
XI. Stormwater (required by DWQ)
Describe impervious acreage (existing and proposed) versus total acreage on the site. Discuss
stormwater controls proposed in order to protect surface waters and wetlands downstream from
the property. If percent impervious surface exceeds 20%, please provide calculations
demonstrating total proposed impervious level. The site total is 4.79 acres. The existing
impervious areas are 0.28 Ac. The proposed impervious areas are 1.29 Ac. 27%. Storage
chambers (stormtrap system) and level spreaders designed per DWQ guidelines will be utilized.
See stormwater plan (pg. 7) for full details for calculations on nitrogen and buydown payment.
XII. Sewage Disposal (required by DWQ)
Clearly detail the ultimate treatment methods and disposition (non-discharge or discharge) of
wastewater generated from the proposed project, or available capacity of the subject facility.
The site will utilize the local municipal sewer & water.
XIII. Violations (required by DWQ)
Is this site in violation of DWQ Wetland Rules (15A NCAC 2H .0500) or any Buffer Rules?
Yes ? No
Is this an after-the-fact permit application? Yes ? No
Page 12 of 13
Permit Number: 08 -- 15q6
(to be provided by DWQ)
Drainage Area Number:
Filter Strip, Restored Riparian Buffer and Level Spreader
Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
- Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
- Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary.
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after every storm event greater than 1.0 inch (or 1.5 inches if in a Coastal County).
Records of operation and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: How I will remediate the problem:
The entire filter strip Trash/ debris is present. Remove the trash/ debris.
system
The flow splitter device The flow splitter device is Unclog the conveyance and dispose
(if applicable) clogged. of an sediment off-site.
The flow splitter device is Make any necessary repairs or
damaged. replace if damage is too large for
repair.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3
Page 1 of 4
BMP element: Potential problem: How I will remediate the problem:
The Swale and the level The swale is clogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and water
bypassed it. until it is established. Provide lime
and a one-time fertilizer application.
Trees or shrubs have begun to Remove them.
grow on the swale or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control.
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material.
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable). approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip. restabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species. possible. If pesticide is used, do not
allow it to get into the receiving
water.
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet. 401 Oversight Unit at 919-733-1786.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3
Page 2 of 4

Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the performance
of the maintenance procedures listed above. I agree to notify DWQ of any problems with
the system or prior to any changes to the system or responsible parry.
Project name:Cedar Chest Subdivision
BMP drainage area number:Drainage areas 2 and 3
Print name: ?e c2ngk ,f 4/. ",o% // ?D,
Title: /hAn..vG?rl
Address: 70 -2/a Al.'jdAle- 27`O,T
Phone: 9/1 132 4"41411 /I
Signature:
Date:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lots have been sold and a resident of the subdivision has been named the president.
I, ? O U- R. CC.N15W , a Notary Public for the State of
Q(3 rl-?\ CCt-T6 I+ n?,; County of 14Rkc , do hereby certify that
L C-O 'Yl Otis 6- W0 d CU- i - iC. personally appeared before me this 14{
day of 0 C 4u h t%y' , )-008 , and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My commission expires,
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3
Page 3 of 4
10 - aA - 1?10 l,)

Permit Number:
(to be provided by DWQ)
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev. 3
Page 4 of 4
Permit Number: 08 - 13 418
to be provided by DWQ
Drainage Area Number:
Rain Garden Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a
known set location. Any deficient BMP elements noted in the inspection will be corrected,
repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety
of the public, and the removal efficiency of the BMP.
Important operation and maintenance procedures:
Immediately after the rain garden cell is established, the plants will be watered twice
weekly if needed until the plants become established (commonly six weeks).
Snow, mulch or any other material will NEVER be piled on the surface of the rain
garden cell.
Heavy equipment will NEVER be driven over the rain garden cell.
Special care will be taken to prevent sediment from entering the rain garden cell. Once a
year, a soil test of the soil media will be conducted.
After the rain garden cell is established, I will inspect it once a month and within 24 hours
after every storm event greater than 1.0 inches (or 1.5 inches if in a Coastal County).
Records of operation and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall be
repaired immediately.
BNW element: Potential problemse How I will remediate the problem:
The entire BMP Trashf debris is resent. Remove the trash/debris.
The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to
rain garden cell erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
The inlet device: pipe, The pipe is clogged (if Unclog the pipe. Dispose of the
stone verge or swale applicable). sediment off-site.
The pipe is cracked or Replace the pipe.
otherwise damaged (if
applicable).
Erosion is occurring in the Regrade the swale if necessary to
swale (if applicable). smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
Stone verge is clogged or Remove sediment and clogged
covered in sediment (if stone and replace with clean stone.
applicable).
Form SW401-Rain garden O&M-Rev.3 Page I of 4
BMP element: Potential problems: How I will remediate the problem:
The pretreatment area Flow is bypassing Regrade if necessary to route all
pretreatment area and/ or flow to the pretreatment area.
gullies have formed. Restabilize the area after grading.
Sediment has accumulated to Search for the source of the
a depth greater than three sediment and remedy the problem if
inches. possible. Remove the sediment and
restabilize the pretreatment area.
Erosion has occurred. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
Weeds are present. Remove the weeds, preferably by
hand.
The rain garden cell: Best professional practices Prune according to best professional
vegetation show that pruning is needed practices.
to maintain optimal plant
health.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessary.
Tree stakes/wires are present Remove tree stake/wires (which
six months after planting. can kill the tree if not removed).
The rain garden cell: Mulch is breaking down or Spot mulch if there are only random
soils and mulch has floated away. void areas. Replace whole mulch
layer if necessary. Remove the
remaining much and replace with
triple shredded hard wood mulch at
a maximum depth of three inches.
Soils and/ or mulch are Determine the extent of the clogging
clogged with sediment. - remove and replace either just the
top layers or the entire media as
needed. Dispose of the spoil in an
appropriate off-site location. Use
triple shredded hard wood mulch at
a maximum depth of three inches.
Search for the source of the
sediment and remedy the problem if
possible.
An annual soil test shows that Dolomitic lime shall be applied as
pH has dropped or heavy recommended per the soil test and
metals have accumulated in toxic soils shall be removed,
the soil media. disposed of properly and replaced
with new planting media.
Form SW401-Rain garden O&M-Rev.3 Page 2 of4
BMP element Potential problems How I will remediate the problem
The underdrain system (if
applicable Clogging has occurred. Wash out the underdrain system
The drop inlet Clogging has occurred. Clean out the drop inlet. Dispose of the
sediment off-site.
The drop inlet is damaged. Repair or replace the drop inlet.
Erosion or other signs of damage Contact the NC Division of Water
The receiving water have occurred at the outlet. Quality 401 Oversight Unit at 919-
733-1786.

Sample Operation and Maintenance Provisions for Water Harvesting Systems
BMP element: Potential blame: How to remediate the lam:
The entire system A component of the system is Make any necessary repairs or replace if
damaged or leaking, damage is too large for repair.
Water is flowing out of the Check system for clogging and damage. Repair
overflow pipe during a as needed so the design volume is stored
design rainfall or smaller properly without discharging during a design
(usually a 1" or 1.5" rainfall). storm
Check that the pump is operating properly and
that the water is actually being used at the
volume designed.
If it is still not operating properly, then consult
an expert
The captured roof area Excess debris or sediment is Remove the debris or sediment as soon as
resent on the rooftop. possible.
The gutter system Gutters are clogged, or water Unclog and remove debris. May need to install
is backing up out of the gutter screens to prevent future clogging.
tter system.
Rooftop runoff not making it Correct the positioning or installation of gutters.
into gutter system. Replace if necessary to capture the roof runoff.
The cistern Sediment accumulation of 5% Remove sediment
or more of the des" volume.
Algae growth is present Do not allow sunlight to penetrate the cistern.
inside the cistern. Treat the water to remove /prevent algae-
Mosquitoes in the cistern. Check screens for damage and repair/replace.
Treat with'm uito dunks' if necessary.
The screens and filters Debris and/or sediment has Search for the source of the debris/sediment
accumulated. Screens and and remedy the problem if possible.
filters are clogged. Clean/clear debris/sediment from screen or
filter. Replace if it cannot be cleaned.
BMP element: Potential problems: How to remediate the roblem:
The pump Pump is not operating Check to see if the system is clogged and flush if
properly. necessary. If it is still not operating, then
consult an expert.
The overflow pipe Erosion is evident at the Stabilize immediately.
overflow dis -har oint
The overflow i is dogged. Undo or replace if it cannot be unclogged.
The outflow i is damaged. Repair or replace the pipe.
The secondary water Not operating properly. -
Consult an expert
su
Form SW401-Rain garden O&M-Rev.3 Page 3 of 4
BMP element Potential problems How I will remediate the problem
The underdrain system (if
applicable Clogging has occurred. Wash out the underdrain system
The drop inlet Clogging has occurred.

The drop inlet is damaged. Clean out the drop inlet. Dispose of the
sediment off-site.
Repair or replace the drop inlet.
The receiving water Erosion or other signs of damage
have occurred at the outlet. Contact the NC Division of Water Quality
401 Oversight Unit at 919-733-1786.

Form S W401-Rain garden O&M-Rev.3 Page 3 of 4
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the performance of
the maintenance procedures listed above. I agree to notify DWQ of any problems with the
system or prior to any changes to the system or responsible party.
Project name: Cedar Chest Subdivision _
BMP drainage area number: Lot 8 Rain Garden _
Printname: 1-cf 1va.,?? f'' _
Title:
Address: -7G1 0,24Wzw //O,oD ?fY/fc.21v /?141e, /VL?7lG1?
Phone: 5/s cp-qa K/Y
Signature:
Date: /G//y???? -
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots
have been sold and a resident of the subdivision has been named the president.
I, o ui- r, ? aA\ I &C ., a Notary Public for the State of
County of yyf okt , do hereby certify that
Le a-h kxz W 6 46-1$Aonally appeared before me this l ++I--N
day of 0 L+ b-( ,f ?fi 0 'and acknowledge the due execution of the
forgoing rain garden maintenance requirements. Witness my hand and official seal,
: ? ( V?
SEAL
My commission expires

Form SW401-Rain garden I&M-Rev. 2 Page 4 of4
Exp C)2- 134%
Cedar Chest Subdivision
Table of Contents
Backup Calculations
General Info "C" Factor tables
Existing conditions
Proposed conditions
Precipitation Table
Lot 8 Runoff Volume Calculations
Time of Concentration table
Area 1(A) Stormwater calculations
Area 2(B) Stormwater calculations
Underdrain Calculation
Area 2 Level Spreader
Stormwater Calculations
Level Spreader designed for 10yr storm
Area 3 Level Spreader
Stormwater Calculations
Level Spreader designed for 10yr storm
L?
UE, .y? fER.QUP.L??''
?? i U?iv?S A^'•V SrORPA`'?',?:FEi 8t?''a?!?ii
Composite "C" Factor
Cedar Chest Lot 8
Existn condtion
Type of Cover Area SF Area AC "C" factor Area*C
Bldg 0.00 1 0.00
Drives 0.00 0.95 0.00
Lawn 11, 372.00 0.26 0.2 0.05

0.05
Total Drainage Area
Composite "C"
Composite "C" Factor
Cedar Chesst
Existing Condition
11, 372.00 0.26
Area 2
0.20
Type of Cover Area SF Area AC "C factor Area*C
Ex. Bldg 3318 0.08 1 0.08
Ex. Drives 8191 0.19 0.95 0.18
Bldg 0.00 1 0.00
Road 0.00 0.95 0.00
Sidewalk 0.00 0.95 0.00
Lawn 92,960.00 2.13 0.2 0.43
0.68
Total Drainage Area
Composite "C"
Composite "C" Factor
Cedar Chesst
Existing Condition
104,469.00 2.40
Area 3
0.28
Type of Cover Area SF Area AC "C factor Area*C
Ex. Bldg 5026 0.115 1 0.12
Ex. Drives 1371 0.031 0.95 0.03
Bldg 0.00 1 0.00
Road 0.00 0.95 0.00
Sidewalk 0.00 0.00 0.95 0.00
Lawn 90,949.00 2.088 0.2 0.42
0.56
Total CA
Total CA
Total Drainage Area 97,346.00 2.23
Composite "C" 0.25
Composite "C" Factor
Cedar Chest Lot 8
Proposed
Type of Cover Area SF Area AC "C factor Area"C
Bldg 4,200.00 0.10 1 0.10
Drives 730.00 0.02 0.95 0.02
Lawn 6,442.00 0.15 0.2 0.03

0.14
Total Drainage) 11,372.00 0.26
Composite "C" 0.54
Composite "C" Factor
Cedar Chesst Area 2
Proposed Conditions
Type of Cover Area SF Area AC "C" factor Area*C
Ex. Bldg 2648 0.06 1 0.06
Ex. Drives 1027 0.02 0.95 0.02
Bldg 20,000.00 0.46 1 0.46
Road 9,171.00 0.21 0.95 0.20
Sidewalk 2,516.00 0.06 0.95 0.05
Lawn 69,107.00 1.59 0.2 0.32
1.11
Total Drainage 1 104,469.00 2.40
Composite "C" 0.46
Composite "C" Factor
Cedar Chesst Area 3
Proposed Conditions
Type of Cover Area SF Area AC "C" factor Area* C
Ex. Bldg 4356 0.10 1 0.10
Ex. Drives 980 0.02 0.95 0.02
Bldg 15,000.00 0.34 1 0.34
Road 4,550.00 0.10 0.95 0.10
Sidewalk 0.00 0.00 0.95 0.00
Lawn 72,460.00 1.66 0.2 0.33
0.90
Total CA
Total CA
Total Drainage) 97,346.00 2.23
Composite "C" 0.40
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0

POINT PRECIPITATION '`? ?
FREQUENCY ESTIMATES j
FROM NOAA ATLAS 14 ll nl N
RALEIGH NC STATE UNIV, NORTH CAROLINA (31-7079) 35.7944 N 78.6989 W 400 feet
from "Precipitation-Frequency Atlas of the United States" NOAA Atlas 14, Volume 2, Version 3
G.M_ Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. 12iley
NOAH, National Weather Service, Silver Spring, Maryland, 2004
Extracted: Mon Sep 22 2008
Confidence Limits Seasonality Location Maps ! Other Info. GIS data ` -Maps Docs 9 Retum to State Map §
Precipitation Intensity Estimates (in/hr)
ARI*
5 min 10 15 30 60 120
3 h
6 h 12 24 48 4 7 10 20 30 45 60

(years)
min
min
min
min
min r r
hr
hr
hr
day
day
day
day
day
day
da
1 4.82 3.86 3.21 2.20 1.37 0.80 0.56 0.34 0.20 0.12 0.07 0.04 0.03 0.02 0.01 0.01 0.01 0.01
2 5.64 4.51 3.78 2.61 1.64 0.96 0.68 0.41 0.24 0.14 0.08 0.05 0.03 0.02 0.02 0.01 0.01 0.01
5 6.49 5.20 4.38 3.11 2.00 1.18 0.84 0.50 0.30 0.18 0.10 0.06 0.04 0.03 0.02 0.02 0.01 0.01
10 7.21 5.76 4.86 3.52 2.29 1.36 0.97 0.59 0.35 0.21 0.12 0.07 0.04 0.03 0.02 0.02 0.01 0.01
25 7.94 6.34 5.35 3.96 2.64 1.59 1.15 0.70 0.42 0.25 0.14 0.08 0.05 0.04 0.02 0.02 0.02 0.01
50 8.48 6.76 5.70 4.30 2.91 1.78 1.29 0.79 0.47 0.28 0.16 0.09 0.06 0.04 0.03 0.02 0.02 0.01
100 8.98 7.13 6.01 4.60 3.17 1.95 1.44 0.88 0.53 0.31 0.18 0.10 0.06 0.05 0.03 0.02 0.02 0.02
200 9.38 7.44 6.26 4.87 3.42 2.13 1.59 0.97 0.59 0.35 0.19 0.11 0.07 0.05 0.03 0.02 0.02 0.02
500 9.84 7.78 6.53 5.20 3.73 2.36 1.79 1.10 0.68 0.39 0.22 0.12 0.08 0.06 0.04 0.03 0.02 0.02
1000 10.20 8.03 6.72 5.44 3.97 2.55 1.95 1.21 0.75 0.43 0.24 0.13 0.08 0.06 0.04 0.03 0.02 0.02
* These precipitation frequency estimates are based on a partial duration series. ARI is the Average Recurrence Interval.
Please refer to NOAA Atlas 14 Document for more information. NOTE: Formatting forces estimates near zero to appear as zero.
* Upper bound of the 90% confidence interval
Precipitation Intensity Estimates (in/hr)
ARI** 5 10 15 30 60 120 3 6 12 24 48 4 7 10 20 30 45 60
(years) min min min min min min hr hr hr hr hr day day day day day day day
1 5.27 4.21 3.50 2.40 1.50 0.88 0.62 0.37 0.22 0.13 0.07 0.04 0.03 0.02 0.01 0.01 0.01 0.01
2 6.16 4.93 4.13 2.85 1.79 1.05 0.74 0.45 0.26 0.16 0.09 0.05 0.03 0.03 0.02 0.01 0.01 0.01
5 7.08 5.66 4.78 3.39 2.18 1.29 0.92 0.55 0.33 0.19 0.11 0.06 0.04 0.03 0.02 0.02 0.01 0.01
10 7.85 6.28 5.29 3.83 2.50 1.49 1.07 0.64 0.38 0.23 0.13 0.07 0.05 0.04 0.02 0.02 0.01 0.01
25 8.65 6.89 5.83 4.32 2.87 1.74 1.26 0.76 0.45 0.27 0.15 0.08 0.05 0.04 0.03 0.02 0.02 0.01
50 9.24 7.36 6.21 4.67 3.17 1.94 1.41 0.86 0.51 0.30 0.17 0.09 0.06 0.05 0.03 0.02 0.02 0.02
100 9.76 7.75 6.53 5.00 3.45 2.13 1.57 0.96 0.58 0.34 0.19 0.10 0.07 0.05 0.03 0.02 0.02 0.02
200 10.22 8.11 6.82 5.31 3.72 2.33 1.73 1.06 0.64 0.37 0.21 0.11 0.07 0.05 0.03 0.03 0.02 0.02
500 10.73 8.48 7.12 5.66 4.06 2.58 1.95 1.20 0.73 0.42 0.23 0.13 0.08 0.06 0.04 0.03 0.02 0.02
1000 11.14 8.77 7.34 5.94 4.34 2.78 2.13 1.32 0.81 0.46 0.26 0.14 0.09 0.06 0.04 0.03 0.02 0.02
' The upper bound of the confidence interval at 90% confidence level is the value which 5% of the simulated quantile values for a given frequency are greater than.
These precipitation frequen cy estimates are based on a partial duration series. ARI is the Average Recurrence Interval .
Please refer to NOAA Atlas 1 4 Document for more information. NOTE: Formatting prevents estimates near zero to appear as zero
.
* Lower bound of the 90% confidence interval
Precipitation Intensity Estimates (in/hr)
ARI** 5 10 15 30 60 120 3 6 12 24 48 4 7 10 20 30 45 60
(years) min min min min min min hr hr hr hr hr day day day day day day day
1 4.43 3.53 2.95 2.02 1.26 0.73 0.52 0.31 0.18 0.11 0.06 0.04 0.02 0.02 0.01 0.01 0.01 0.01
2 5.18 4.14 3.47 2.40 1.50 0.88 0.62 0.37 0.22 0.13 0.08 0.04 0.03 0.02 0.02 0.01 0.01 0.01
5 5.96 4.78 4.03 2.86 1.83 1.07 0.76 0.46 0.27 0.17 0.10 0.05 0.03 0.03 0.02 0.01 0.01 0.01
10 6.60 5.28 4.46 3.23 2.10 1.24 0.89 0.54 0.32 0.20 0.11 0.06 0.04 0.03 0.02 0.02 0.01 0.01
25 7.26 5.78 4.88 3.62 2.41 1.44 1.04 0.63 0.38 0.23 0.13 0.07 0.05 0.04 0.02 0.02 0.01 0.01
50 7.72 6.14 5.18 3.90 2.65 1.60 1.16 0.71 0.43 0.26 0.15 0.08 0.05 0.04 0.03 0.02 0.02 0.01
9/22/2008 3:33 PM
Permit Number
(to be provided by DWQ)

??
s of WATEq
A
?
NCDENR O e w ?t"'j'• -~c
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
BIORETENTION CELL SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part ill) must be printed, filled out and submitted along with all of the required information.
1. PROJECT INFORMATION
Project name Cedar Chest Subdivision
Contact name Carl Simmons
Phone number 919-833-0830
Date October 13, 2008
Drainage area number Lot 8 Rain Garden
It. -DESIGN INFORMATION
Site Characteristics
Drainage area 11,372 ft2
Impervious area 6,000 ft
Percent impervious 52.8% %
Design rainfall depth 1.0 inch
Peak Flow Calculations
Is pre/post control of the 1-yr, 24-hr peak flow required? y (Y or N)
1-yr, 24-hr runoff depth in
Tyr, 24-hr intensity 5• G4 in/hr
Pre-developmentt.yr, 24-hr peak flow 0.:30 ft3/sec
Post-development,-yr, 24-hr peak flow 0 . f3) ft3/sec
Pre/Postl; yr, 24-hr peak control 0.25 ft3/sec
Storage Volume: Non-SA Waters
Minimum volume required "0 ft3
Volume provided E5 7_,Z ft3
Storage Volume: SA Waters
1.5' runoff volume ft3
Pre-development 1-yr, 24-hr runoff ft3
Post-development 1-yr, 24-hr runoff ft 3
Minimum volume required 0 ft3
Volume provided ft3
Cell Dimensions
Ponding depth of water 9 ° inches
Ponding depth of water U 15' 0.00 ft
Surface area of the top of the bioretention cell &1161 ft2
Length: •3& ft
Width: ??f ± ft
-or- Radius ft
Soils Report Summary
Drawdown time, ponded volume °I hr
Drawdown time, to 24 inches below surface Z4 hr
Drawdown time, total: 0 hr
In-situ soil:
Soil permeability in/hr
Planting media soil:
Soil permeability I in/hr
Soil composition
% Sand (by weight)
Form SW401-Bioretention-Rev.4 Parts 1 and II. Design Summary, Page 1 of 2
Permit Number:
(to be provided by DWQ)
% Fines (by weight)
% Organic (by weight)
Phosphorus Index (P-Index) of media
Basin Elevations
Temporary pool elevation
Planting elevation (top of the mulch)
Bottom of the cell
Planting depth
Depth of mulch
SHWT elevation
8-12.4
'7C,
Total: 0%
V>--Zo (unitless)
-174.16 fmsl
274, U fmsl
C) fmsl
3 ° oft
3 inches
^v fmsl
Are underdrains being installed? I (Y or N)
How many clean out pipes are being installed? is
What factor of safety is used for sizing the underdrains? (See
BMP Manual Section 12.3.6)
Additional distance between the bottom of the planting media and 0 ft
the bottom of the cell to account for underdrains
Bottom of the cell required 11o 0 fmsl
Distance from bottom to SHWT -?. 0 ft
Type of bioretention cell (answer "Y" to only one of the two
following questions):
Is this a grassed cell? Y (Y or N)
Is this a cell with trees/shrubs? r• i (Y or N)
Planting Plan
Number of tree species 0
Number of shrub species 0
Number of herbaceous groundcover species l is Additional Information

Does volume in excess of the design volume bypass the (Y or N)
bioretention cell?
Does volume in excess of the design volume flow evenly distributed (Y or N)
through a vegetated filter?
What is the length of the vegetated filter? ft
Does the design use a level spreader to evenly distribute flow?
Is the BMP located at least 30 feet from surface waters (50 feet if
SA waters)?
Is the BMP located at least 100 feet from water supply wells?
Are the vegetated side slopes equal to or less than 3:1?
Is the BMP located in a recorded drainage easement with a
recorded access easement to a public Right of Way (ROW)?
Inlet velocity (from treatment system)
Y (Y or N) (A4 e ej4rj ffIn4s
(Y or N)
(Y or N)
Y (Y or N)
?e, (Y or N)
ft I ft/sec
Is the area surrounding the cell likely to undergo development in (Y or N)
the future?
Are the slopes draining to the bioretention cell greater than 20%? ?A (Y or N)
Is the drainage area permanently stabilized? Aj (Y or N)
Pretreatment Used
(Indicate Type Used with an "X" in the shaded cell)
Gravel and grass
(81inches gravel followed by 3-5 It of grass)
Grassed swale
Forebay
Other
Form SW401-Bioretention-Rev.4 Parts I and II. Design Summary, Page 2 of 2
Pennft No:
(to be assigned by DWQ)
Ill. REQUIRED ITEMS "CHECKLIST
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.
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),
Cell dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
- Recorded drainage easement and public right of way (ROW),
Clean out pipe locations,
Overflow device, and
Boundaries of drainage easement.
2. Plan details (1' = 30' or larger) for the bioretention cell shaving:
Cell dimensions
Pretreatment system,
High flow bypass system,
Maintenance access,
Recorded drainage easement and public right of way (ROW),
Design at ultimate build-out,
Off-site drainage (if applicable),
Clean out pipe locations,
- Overflow device, and
Boundaries of drainage easement.
Indicate the P-Index between 10 and 30
JAY?- '15 3. Section view of the bioretention cell (1" = 20' or larger) showing:
The source nursery for the plants, and
Fonn SW401-Bioretention-Rev.4
-Side slopes, 3:1 or lower
- Underdrain system (if applicable), and
Bioretention cell layers (ground level and slope, pre-treatment, ponding depth, mulch depth, fill media
depth, washed sand, filter fabric (or choking stone if applicable), #57 stone, underdrains (if applicable),
SHWT level(s), and overflow structure]
4. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The
by completing
results of the soils report must be verified in the field by DWQ, & submitting the soils
ble
investigation request form. County soil maps are not an accept source of soils information. All
tests of
elevations shall be in feet mean sea level (fmsl). Results of soils both the planting soil and the in
situ soil must include:
-Soil permeability,
-Soil composition (% sand, % fines, % organic), and
- P-index.
tied individual
5. A detailed planting plan (1" = 20' or larger) prepared by a quali showing:
A variety of suitable species,
-
-Sizes, spacing and locations of plantings,
- Total quantity of each type of plant specified,
- A planting detail,
-Fertilizer and watering requirements to establish vegetation.
cations
6. An assurance that the installed system will meet design specifi upon initial operation once the
project is complete and the entire drainage area is stabilized.
ll be protected from sediment until the
7. A construction sequence that shows how the bioretention cell wi
entire drainage area is stabilized.
applicable).
iln? ?r f 8. The supporting calculations (inducting underdrain calculations, if
(I&M)
9. A copy of the signed and notarized inspection and maintenance agreement.
10. A copy of the deed restriction.
Part III, Page 7 of 1
e--) 0574 C,%
G Cr?c?
/l 3 70 moo' l::7
'o •?5?
/? y ' ??)0153 G1. 5-Z7
5z7
26- }
?- 46
Loo
Lo"ale, ( 5
NCDENR Stormwater BMP Manual Chapter Revised 09-28-07
allows the user to select from one of NOAA's numerous data stations throughout the
state. Then, the user can ask for precipitation intensity and view a table that displays
precipitation intensity estimates for various annual return intervals (ARIs) (1 year
through 1000 years) and various storm durations (5 minutes through 60 days).
The requirements of the applicable stormwater program will determine the appropriate
values for ARI and storm duration. If the design is for a level spreader that is receiving
runoff directly from the drainage area, then the value for I should simply be one inch
per hour (more information on level spreader design in Chapter 8).
3.3. Runoff Volume
Many stormwater programs have a volume control requirement; that is, capturing the
first 1 or 1.5 inches of stormwater and retaining it for 2 to 5 days. There are two primary
methods that can be used to determine the volume of runoff from a given design storm:
the Simple Method (Schueler,1987) and the discrete SCS Curve Number Method (NRCS,
1986). Both of these methods are intended for use at the scale of a single drainage area.
Stormwater BMPs shall be designed to treat a volume that is at least as large as the
volume calculated using the Simple Method. If the SCS Method yields a greater volume,
then it can also be used.
3.3.1. Simple Method
The Simple Method uses a minimal amount of information such as watershed drainage
area, impervious area, and design storm depth to estimate the volume of runoff. The
Simple Method was developed by measuring the runoff from many watersheds with
known impervious areas and curve-fitting a relationship between percent
imperviousness and the fraction of rainfall converted to runoff (the runoff coefficient).
This relationship is presented below:
Rv = 0.05 +0.9 * IA
Where: Rv = Runoff coefficient [storm runoff (in)/storm rainfall (in)], unitless
IA = Impervious fraction [impervious portion of drainage area (ac)/
drainage area (ac)], unitless.
Once the runoff coefficient is determined, the volume of runoff that must be controlled is
given by the equation below:
V=3630*RD*R,*A
Where: V = Volume of runoff that must be controlled for the design storm (W)
RD = Design storm rainfall depth (in) (Typically, 1.0" or 1.5")
A = Watershed area (ac)
Stormwater Management and Calculations 3-3 July 2007
Bwokffdge
Runoff Calc
1-*T797:17Cui
i"'c
wens
DOWNTOWN
NEIGHBORHOOD
SINGLE FAMILY.
'AULTI UNITS, DET
MULTI 11NFFS, ATT
ar Rainfall linens' ID- WMBTWL:
low 0.699 LUSHT AREAS
Flow 0.9 HEAVY AREAS
(PARKS, CEMETARIES
:PLAYGROUNDS
RAILROAD YARD AREAS
UNIMPROVED AREAS
?TREM-
Solving for Time of Concentration
Kinematic Wave Theory
Length of overland flow kRRUM] feet --Sorface.'M4I n
Manni s"n"forsurface 0240 Smtiolh Surface 0.011
-rage watershed slo pe n. Rt. Fallow - 005D
0.7-095 ~.onstant alpha 2778 Cultivated,-20%-Residue 0.060
-0,5-0.7 c "Islam m MIMMI CtiHlvated :7096=Res idue- 0.170
Weighted Runoff Coefficient 04789231 1 Grass,Short -0.150
0.3-0.5 Grasse P e e ".0.240
0.4-08 -Grass 'Bermuda "-0:410
0.&0.75 - 'Woodscu m `x0.400
0.2504 ` ?Woods, Dense <^0.800
0.5-4) A -.-?Trail Time of Duration (Rainfall Intensity(IDF) (Calculation 0 Time of Concentration
1) _0-0.9 dnaea)
N' i (ncheanwur) I. (-.t.)
0,1-0.25 _
htl c//hdsanws.noaa. ov/hdsc/fds/orb/nc fds.htmI
020.35 4.13
0.2-0.4 F` 4:51
0.1-0.3 fs '. 4.83
ASPHALT 0.7-0.95 8.53
CONCRETE 0.M9 i5 r 8.04
BRICK _ 0.7-0.85 - 931
`DRIVES AND WALK6 D]5-0.85 11.24
?ROSES 015-1185 13.85
'LAMM; M swim 18.99
SANDY:SOIL, FLAT, 2% 0.05-0,1
SANDY SOIL, AVE. 2-7% 0.1-015 Enter the Rainfall Intensity Values for the Corresponding Times of Duration from the NWS hyperlink provided.
SANDY SOIL, STEEP, 71,6 015-0 2 Select the Trial Time of Duration that is a ual to or less than the calculated Time of Concentration, or the Calculated 1
of Concentration U less than 6 minutes. This is [he overland now component of the Time of Concentration.
-4 Overland Flow tc I?n,nec;?
HEAVYSOIL;FLAT, 2% 0,13-0.17
HEAVY SOIL, AVE.. 2-7% 0.1&0.22 Calculate he shallow concentrated now component of the Time of Concentration.
HEAVY 301L, STEEP, ,.7%, 0.250.35 Calculate channel how coin nent of ime of Concentration.
'AaI`dCULTURAL LAnD: r< Sum these three components. This ,!W total Time of Concentration.
fl4RE PACYED 5(111.
SMOOTH 0.3-0.e Shallow Concentrated Flow (Channel Flow
ROUGH, 0.2-0.5
UUL iJ yA7 D, FhU1i'-1 (Paved
HEAW;801C'tJO CROP, - 0.3-0.6 Flow Length Flow Le h
HEAVY SOIL WfTHCROP . 0.2-0.5 81opa Slope
'SANDY 501L NO CROP 02-0.4 plc (mirMes) 0.0 H raulic Radius JJJM?
SANDY:SOILNTH CROP 0.1-0.25 i Un d Mimmd s n MUM
PASTURE f_ Le h Ic (mw,wesl 0.4
HEAVY SOIL 0.15-0a5 Lope
'SANDY .SOIL 0.050.25 SIC ^ ? ? 0.0
`aNDODLAND6 ...'0:05.0:25
Total Time of Concentration 4.5
Revised !!/1/2006 TGH
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SPREADER #3.
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Project: New.GPW OF raleigh ncsu.IDF 6 hyd's 10-13-2008
Hydrograph Summary Report
Page 1
Hyd.
No. Hydrograph
type
(origin) Peak
now
(cfs) Time
interval
(min) Time to
peak
(min) Volume

(cult) Return
period
(yrs) Inflow
hyd(s) Maximum
elevation
(ft) Maximum
storage
(cult) Hydrograph
description
1 Rational 0.24 1 5 71 2 - - -- Lot 8 area 1 pre
2 Rational 0.53 1 5 160 2 - - -- Lot 8 area 1 post
3 Reservoir 0.19 1 8 160 2 2 281.35 90 Lt 8 area 1 w.stor
4 Rational 0.30 1 5 91 10 -- - Lot 8 area 1 pre Q
5 Rational 0.68 1 5 204 10 - - --- Lot 8 area 1 post
6 Reservoir 0.23 1 8 204 10 5 281.91 123 010 post w. storag
Proj. file: New.GPW OF file: raleigh ncsu.IDF Run date: 10-13-2008
Reservoir Report Page 1
English
Reservoir No. 1 - Lt 8 pipe storage
Pond Data
Pipe diameter = 2.00 ft
Stage / Storage Table
Stage Elevation
ft ft
0.00 280.00
0.20 280.20
0.40 280.40
0.60 280.60
0.80 280.80
1.00 281.00
1.20 281.20
1.40 281.40
1.60 281.60
1.80 281.80
2.00 282.00
Pipe length = 40.0 ft Invert elevation = 280.00 ft
Contour area Incr. Storage Total storage
sgft cult cuft
00 0 0
00 7 7
00 11 18
00 14 32
00 15 47
00 16 63
00 16 79
00 15 94
00 14 108
00 11 119
00 6 126
Culvert / Orifice Structures
[A] [B] [C] [D]
Rise in = 3.0 0.0 0.0 0.0
Span in = 3.0 0.0 0.0 0.0
No. Barrels = 1 0 0 0
Invert El. ft = 280.00 0.00 0.00 0.00
Length ft = 20.0 0.0 0.0 0.0
Slope % = 1.00 0.00 0.00 0.00
N-Value = .013 .000 .000 .000
Ord. Coeff. = 0.60 0.00 0.00 0.00
Multi-Stage = ---- No No No
Weir Structures
[A]
Crest Len ft = 0.0
Crest El. ft = 0.00
Weir Coeff. = 0.00
Eqn. Exp. = 0.00
Multi-Stage = No
[B] [C] [D]
0.0 0.0 0.0
0.00 0.00 0.00
0.00 0.00 0.00
0.00 0.00 0.00
No No No
Tailwater Elevation = 0.00 ft
Note: All outflows have been analyzed under inlet and outlet control.
Stage / Storage / Discharge Table
Stage Storage Elevation Clv A Clv B Clv C Clv D Wr A Wr B Wr C Wr D Discharge
It cult ft cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.00 0 280.00 0.00 --- --- -- -- -- -- --- 0.00
0.20 7 280.20 0.06 -- -- - -- --- -- --- 0.06
0.40 18 280.40 0.10 - --- --- -- --- -- --- 0.10
0.60 32 280.60 0.13 - -- - -- -- -- -- 0.13
0.80 47 280.80 0.15 --- - -- --- - --- -- 0.15
1.00 63 281.00 0.16 - --- -_ __ __ W 0.16
1.20 79 281.20 0.18 --- --- - -- -- - -- 0.18
1.40 94 281.40 0.20 --- --- - --- --- -- -- 0.20
1.60 108 281.60 0.21 -- -- --- - --- - --- 0.21
1.80 119 281.80 0.22 - --- - - -- -- -- 0.22
2.00 126 282.00 0.24 - -- --- --- -- --- --- 0.24
Hydrograph Plot
English
Hyd. No. 1
Lot 8 area 1 pre
Hydrograph type = Rational Peak discharge = 0.24 cfs
Storm frequency = 2 yrs Time interval = 1 min
Drainage area = 0.2 ac Runoff coeff. = 0.2
Intensity = 5.64 in Time of conc. (Tc) = 5 min
I-D-F Curve = raleigh ncsu.IDF Reced. limb factor = 1

Total Volume = 71 cult
Hydrograph Plot
Hyd. No. 2
Lot 8 area 1 post
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 2 yrs
= 0.2 ac
= 5.64 in
= raleigh ncsu.IDF
English
Peak discharge = 0.53 cfs
Time interval = 1 min
Runoff coeff. = 0.45
Time of conc. (Tc) = 5 min
Reced. limb factor= 1
Total Volume = 160 cult
Hydrograph Plot
English
Hyd. No. 3
Lt 8 area 1 w.storage
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Inflow hyd. No. = 2
Max. Elevation = 281.35 ft
Peak discharge
Time interval
Reservoir name
Max. Storage
= 0.19 cfs
= 1 min
= Lt 8 pipe stora
= 90 cuft
Storage Indication method used.
Total Volume = 160 cuft

3-Re
servoir -
2Yr-Qp
=0.19 cf ?I
s

0.
/ Hyd. 2
0.
w
v 0.
CY

i
0.
0
. / Hyd. 3
0
.
2 0 3 0 4 0
i
i
Time (mi
n)

i I

0
0 1 0
Hydrograph Plot
English
Hyd. No. 4
Lot 8 area 1 pre Q10
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 10 yrs
= 0.2 ac
= 7.20 in
= raleigh ncsu.IDF
Peak discharge = 0.30 cfs
Time interval = 1 min
Runoff coeff. = 0.2
Time of conc. (Tc) = 5 min
Reced. limb factor= 1
Total Volume = 91 cult
4 - Rational -10 Yr - Qp = 0.30 cfs
0.4
0
CY 0,
0.
0.

2
?
A
i
1 i
-
-

0 Z
F-7
I
0 2 4 6 8 10
/ Hyd. 4
Time (min)
Hydrograph Plot
English
Hyd. No. 5
Lot 8 area 1 post Q10
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 10 yrs
= 0.2 ac
= 7.20 in
= raleigh ncsu.IDF
Peak discharge = 0.68 cfs
Time interval = 1 min
Runoff coeff. = 0.45
Time of conc. (Tc) = 5 min
Reced. limb factor= 1
Total Volume = 204 cult
6 - Rational -10 Yr - Qp = 0.68 cfs
0.8-
0.6-
0.4-
0.2-
0.0
0

i I
2 4
6 8 10
/ Hyd. 5
Time (min)
Hydrograph Plot
English
Hyd. No. 6
Q 10 post w. storage
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Inflow hyd. No. = 5
Max. Elevation = 281.91 ft
Peak discharge
Time interval
Reservoir name
Max. Storage
= 0.23 cls
= 1 min
= Lt 8 pipe stora
= 123 cult
storage Indication method used. Total Volume = 204 cult
amp
4
ZI
Project: New.GPW IDF: raleigh ncsu.IDF 6 hyd's 10-13-2008
Hydrograph Summary Report
Page 1
Hyd.
No. Hydrograph
type
(origin) Peak
flow
(cfs) Time
interval
(min) Time to
peak
(min) Volume

(cult) Return
period
(yrs) Inflow
hyd(s) Maximum
elevation
(ft) Maximum
storage
(cult) Hydrograph
description
1 Rational 0.06 1 5 17 2 - - -- Lot 8 area 2 pre
2 Rational 0.28 1 5 84 2 - - - Lot 8 area 2 post
3 Reservoir 0.06 1 9 84 2 2 280.23 63 Area 2 w. cistem
4 Rational 0.07 1 5 22 10 - - ---- Lot 8 area 2 pre Q
5 Rational 0.36 1 5 107 10 - - - LOt 8 area 2 post
6 Reservoir 0.06 1 9 107 10 5 281.25 83 Areq 2 w. cistem
Proj. file: New.GPW IDF file: raleigh ncsu.IDF T Run date: 10-13-2008
Reservoir Report Page 1
English
Reservoir No. 1 - Cistern
Pond Data
Bottom area = 19.6 sqft
Stage / Storage Table
Stage Elevation
ft ft
0.00 277.00
0.45 277.45
0.90 277.90
1.35 278.35
1.80 278.80
2.25 279.25
2.70 279.70
3.15 280.15
3.60 280.60
4.05 281.05
4.50 281.50
Side slope = 0.0:1 Bottom elev. = 277.00 ft Depth = 4.50 ft
Contour area Incr. Storage Total storage
sgft cuft cuft
20 0 0
20 9 9
20 9 18
20 9 26
20 9 35
20 9 44
20 9 53
20 9 62
20 9 71
20 9 79
20 88
Culvert / Orifice Structures
[A] [B] [C] [D]
Rise in = 1.5 0.0 0.0 0.0
Span in = 1.5 0.0 0.0 0.0
No. Barrels = 1 0 0 0
Invert El. ft = 277.00 0.00 0.00 0.00
Length ft = 15.0 0.0 0.0 0.0
Slope % = 1.00 0.00 0.00 0.00
N -Value = .013 .000 .000 .000
Orif. Coeff. = 0.60 0.00 0.00 0.00
Multi-Stage = -- No No No
Weir Structures
[A] [B] [C] [D]
Crest Len ft = 0.0 0.0 0.0 0.0
Crest El. ft = 0.00 0.00 0.00 0.00
Weir Coeff. = 0.00 0.00 0.00 0.00
Eqn. Exp. = 0.00 0.00 0.00 0.00
Multi-Stage = No No No No
Tallwater Elevation = 0.00 ft
We: All outflows have been analyzed under inlet and outlet control.
Stage / Storage / Discharge Table
Stage Storage Elevation Clv A Civ B Civ C Clv D Wr A Wr B Wr C Wr D Discharge
ft cult ft cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.00 0 277.00 0.00 0.00
0.45 9 277.45 0.02 -- -- - --- -- -- - 0.02
0.90 18 277.90 0.03 - -- -- --- - --- -- 0.03
1.35 26 278.35 0.04 - - -- -- --- --- --- 0.04
1.80 35 278.80 0.04 --- 0.04
2.25 44 279.25 0.05 --- - --- - -- --- - 0.05
2.70 53 279.70 0.05 -- -- - -- -- -- -- 0.05
3.15 62 280.15 0.06 - - -- --- -- - - 0.06
3.60 71 280.60 0.06 - - --- - - --- - 0.06
4.05 79 281.05 0.06 - --- -- - - - - 0.06
4.50 88 281.50 0.07 --- --- --- --- --- --- --- 0.07
Hydrograph Plot
English
Hyd. No. 1
Lot 8 area 2 pre
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 2 yrs
= 0.1 ac
= 5.64 in
= raleigh ncsu.IDF
Peak discharge = 0.06 cfs
Time interval = 1 min
Runoff coeff. = 0.2
Time of conc. (Tc) = 5 min
Reced. limb factor= 1
Total Volume = 17 cult
1 - Rational - 2 Yr - Qp = 0.06 cfs
0.06
0.(
0.(
0.(
0.(
0.(
0.(
i
r5 --- -L - i 1

13 - --- - f-- -
r

0
0 2 4 6 8 11
/ Hyd. 1
Time (min)
Hydrograph Plot
English
Hyd. No. 2
Lot 8 area 2 post
Hydrograph type = Rational Peak discharge = 0.28 cfs
Storm frequency = 2 yrs Time interval = 1 min
Drainage area = 0.1 ac Runoff coeff. = 0.99
Intensity = 5.64 in Time of conc. (Tc) = 5 min
I-D-F Curve = raleigh ncsu.IDF Reced. limb factor= 1
Total Volume = 84 cult
2 - Rational - 2 Yr - Qp = 0.28 cfs
0.30
0.2
0.20-
JOE
0.1 / Hyd. 2
CY
0.1
0.05-
0.0.
6 8 10
Time (min)
I
I
i
j
{
I

0 2 4 0
Hydrograph Plot
English
Hyd. No. 3
Area 2 w. cistern
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Inflow hyd. No. = 2
Max. Elevation = 280.23 ft
Peak discharge
Time interval
Reservoir name
Max. Storage
= 0.06 cfs
= 1 min
= Cistern
= 63 cuft
storage Indication method used.
3 - Reservoir - 2 Yr - Qp = 0.06 cfs
0.30
0.2!
0.21
CY 0.1!
0.1(
0.0:
0.0(

i T

0 1 0 2 0 3 0 4 0 50 61
Total Volume = 84 cult
/ Hyd. 2
/ Hyd. 3
Time (min)
Hydrograph Plot
English
Hyd. No. 4
Lot 8 area 2 pre Q10
Hydrograph type = Rational
Storm frequency = 10 yrs
Drainage area = 0.1 ac
Intensity = 7.20 in
I-D-F Curve = raleigh ncsu.IDF
Peak discharge = 0.07 cfs
Time interval = 1 min
Runoff coeff. = 0.2
Time of conc. (Tc) = 5 min
Reced. limb factor= 1
Total Volume = 22 cuR
I

0
0$
4-R
ational
-10Yr-Qp= i
0.07 cfs
.
0.
i

0 / Hyd. 4
.
CY j
i
0.02-
0
.
6 8 10
Time (min)

i
I

0
0 2 4 0
Hydrograph Plot
English
Hyd. No. 5
LOt 8 area 2 post Q10
Hydrograph type = Rational Peak discharge = 0.36 cfs
Storm frequency = 10 yrs Time interval = 1 min
Drainage area = 0.1 ac Runoff coeff. = 0.99
Intensity = 7.20 in Time of conc. (Tc) = 5 min
I-D-F Curve = raleigh ncsu.IDF Reced. limb factor= 1
Total Volume = 107 cult
Hydrograph Plot
English
Hyd. No. 6
Areq 2 w. cistern Q10
Hydrograph type = Reservoir Peak discharge = 0.06 cfs
Storm frequency = 10 yrs Time interval = 1 min
Inflow hyd. No. = 5 Reservoir name = Cistern
Max. Elevation = 281.25 ft Max. Storage = 83 cuft
Storage Indication method used. Total Volume = 107 cult
6 - Reservoir -10 Yr - Qp = 0.06 cfs
0.
0.
-102
0.
CJ
0.
0.1
/ Hyd. 5
/ Hyd. 6
Time (min)
0 20 40 60 80

?.f

i
514- = fD

?f

Bmokridge,
Runoff Calc
Rd Basin Number Solving for Time of Concentration
image Area 1 Kinematic Wave Theory
Method for Flow {NNpEF.yoEFFICIEN7
Vn UOE &
?satcae:
DOWNTOWN AREAS 03-085
NEIGHBORHOOD AREAS 00.7
5 REa1DCIrilAL:
Weighted Runoff Coefficient 0.483958 Gri1b5's 1 6'hon >r0150
SINGLE FAMILY AREAS 0 M.5 Gress, Dow r 40340
MULTI UNITS, DETACHED 0.4-0.6 - rGrm;Senhuda ;0.410
d 'MULTI UNITE, ATTACHED :0.&D 75 .WoWS;;I; t - OADD
2
SUBURBAN .6.25-04 ' 00ods;Deoee Ic- .-0
.
ONUSTRY.IL
2 LIGHT AREAS
0.50.-8
Trail Time of Duration
Rainfall Intensily(IDF) Calculation of Time of Concentration
4 H EAVY AREAS ! =0.6-0.9
'.PARKS, CEMETARIES 0.1 X0.25
i PLAYGROUNDS 0.20.35
`4RAILROAD YARD AREAS 0.2-0.4 9.48
UNIMPROVED AREAS 0 10.15
'STREifrfi
ASPHALT 07.0.05
0 13.71
CONCRETE 0,&095 16.89
.BRICK - 0,7-0E5 19.34
,DRIVES AND WALKS C:75-O L5
19.213
..,ROOFS 075-0,85
.. 29.08
;LAw $:
SANDY SOILFLAT, 29A, 0.(KID 1
SANDY SOIL, AVE.,.2-7f8, ? 0.1-0,15 I Enter the Rainfall Intensity Values for the Corresponding Times of Duration from the NWS hyperlink provided.
SANDY SOIL, STEEP, Thy 0.15,0 2 Select the Trial Time of Duration that is equal to or less than the calculated Time of Concentration, or the Calculated I
I m Concentration if less than 5 minrr tes. This is the overland now component of the Time of Concentration.
I0-nand Flow Itc (mi-l
HEAVY SOIL, FLAT. 2`- 0.13-0.17
HEAVY SOIL. AVE., _-7% 01& 0-22 ; . I Calculate the shallow concentrated flow component of the Time of Concentration.
HEAVY SOIL, STEEP, 7% 0.25-0.35 : Calculate the channel flow component of the Time of Concentration.
:A13WLJt.TURA4 LAND-. '.. I Sum these three components. This is the total Time of Concentration.
flN2r. P4CKF1)301L
SMOOTH D.3-0 6 :( Shallow Concentrated Flow (Channel Flow
ROUGH 0205
-. cu[7Na1E1m s -?1 ,Paved
HEAVY SOIL NO CROP 0.3-0.6 Flow Len h Flow Len. th l
HEAVYSOIL WITH CROP -0.2-0.5 ( slope Slo e
SANDY COIL NO CROP 02 0A I tc lrninueesl 0.0 Hydraulic Radius l
ANDY SOIL WITH CROP 0.1-025 [Unpaved Manninsn
aASru,Re Flow Length to (mom} 0.4
HEAVY BOIL, 0.15-0,45 : Slope
SANOYS011 00°1, - tc(rnrwbcl 0.6
v,WOODLuANDEI I 0(08-015 ...
Total Time of Concentration 11.0
car h of overland flow QlM teet 'Surfeee.Manhl n '
Mannings "n" for surface
f Ave watershed slo c:D140
h.m. :Su/1aca -
Fellow OA11
-0.050
Constant al a 1.843 ivaled e ' Residue O:OBo
Constant I WNW Cult"ed > 20%'ResAi a ` - -1o.i7o

Revised 11/12006 TGH
WDENR
OF W A TF,?
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
LEVEL SPREADER, FILTER STRIP AND RESTORED RIPARIAN BUFFER SUPPLEMENT
This form must be completely filled out, printed and submitted.
DO NOT FORGET TO ATTACH THE REQUIRED ITEMS CHECKLIST AND ALL REQUIRED ITEMS (NEXT WORKSHEET)!
1. PROJECT` INFORMATION`
Project name Cedar Chest
Contact name Cadl Simmons
Phone number 833-0830
Date September 23, 2008
Drainage area number Area 2
II. DESIGN-INFORMATION
For Level Spreaders Receiving Flow From a BMP
Type of BMP Underground Dry Detention
Drawdown flow from the BMP 3.81 cfs
For Level Spreaders Receiving Flow from the Drainage Area
Drainage area
Impervious surface area
Percent impervious
Rational C coefficient
Peak flow from the 1 in/hr storm
Time of concentration
Rainfall intensity, 10-yr storm
Peak flow from the 10-yr storm
Where Does the Level Spreader Discharge?
To a grassed bioretention cell?
To a mulched bioretention cell?
To a wetland?
To a filter strip or riparian buffer?
Other (specify)
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass
Width of dense ground cover
Width of wooded vegetation
Total width
Elevation at downslope base of level lip
Elevation at top of bank of the receiving water
Slope (from level lip to to top of bank)
Are any draws present?
Level Spreader Design
Forebay surface area
Feet of level lip needed per cfs
Answer "Y" to one of the following:
Length based on the 1 in/hr storm?
Length based on the 10-yr storm?
Length based on the BMP discharge rate?
Design flow
Is a bypass device provided?
Do not complete this section of the worksheet
ft2 Do not complete this section of the worksheet.
ft2 Do not complete this section of the worksheet.
% Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
cfs Do not complete this section of the worksheet.
min
in/hr Do not complete this section of the worksheet.
cfs Do not complete this section of the worksheet.
N (Y or N)
N (Y or N)
N (Y or N)
Y (Y or N) Please complete filter strip characterization below.
70.00 ft
ft
ft
70.00 ft
266.00 fmsl
263.00 fmsl
4.29 % OK
N (Y or N) OK
sq ft No forebay is needed.
13 ft/cfs
N (Y or N)
Y (Y or N)
Y (Y or N)
3.81 cfs
N (Y or N)
A bypass device is not needed.
Form SW401-Level Spreader, Fier Strip, Restored Riparian Buffer-Rev.5 Parts I. and If. Design Summary, page 1 of 2
Length of the level lip
Are level spreaders in series?
Bypass Channel Design (if applicable)
Does the bypass discharge through a wetland?
Does the channel enter the stream at an angle?
Dimensions of the channel (see diagram below):
M
B
W
y
Peak velocity in the channel during the 10-yr storm
Channel lining material
Do not complete this section of the worksheet

------------
M
50.00 ft #VALUE!
N (Y or N)
(Y or N) Do not complete this section of the worksheet.
(Y or N) Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
ft Do not complete this section of the worksheet,
ft Do not complete this section of the worksheet.
ft Do not complete this section of the worksheet.
ft Do not complete this section of the worksheet.
cfs Do not complete this section of the worksheet.

M
Form SW401-Level Spreader, Fitter Strip, Restored Riparian Buffer-Rev.5 Parts I. and It. Design Summary, page 2 of 2
III. REQUIRED ITEMS.CHECKLIST
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.
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),
- Forebay (if applicable),
High flow bypass system,
Maintenance access,
- Proposed drainage easement and public right of way (ROW), and
Boundaries of drainage easement.
at 2. Plan details (1" = 30' or larger) for the level spreader showing:
- Forebay (if applicable),
- High flow bypass system,
- One foot topo lines between the level lip and top of stream bank,
- Proposed drainage easement, and
- Design at ultimate build-out.
3. Section view of the level spreader (1" = 20' or larger) showing:
- Underdrain system (if applicable),
- Level lip,
- Upslope channel, and
- Downslope filter fabric.
2t 4. A date-stamped photograph of the filter strip that clearly shows the type of vegetation that is present.
5. A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized.
iz(_ 6. The supporting calculations.
'P C-- 7. A copy of the signed and notarized operation and maintenance (0&M) agreement.
8. A copy of the deed restrictions (if required).
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5 Part III, page 1 of 1
Hydrograph Summary Report
Page 1
Hyd.
No. Hydrograph
type
(origin) Peak
flow
(oft) Time
interval
(min) Time to
peak
(min) Volume

(cult) Return
period
(Yrs) Inflow
hyd(s) Maximum
elevation
(ft) Maximum
storage
(tuft) Hydrograph
description
1 Rational 2.93 1 11 1,937 2 - Gaddy 2yr pre 2c
2 Rational 4.82 1 11 3,182 2 - - - Gaddy 2yr post 2c
3 Reservoir 2.33 1 17 3,182 2 2 284.76 1,657 Area 2 with storag
4 Rational 3.81 1 11 2,517 10 ---- Gaddy 10yr pre 2c
5 Rational 6.27 1 11 4,135 10 - - Gaddy 10yr post 2c
6 Reservoir 3.81 1 15 4,135 10 5 285.34 2,007 Area 2c with stor
Proj. file: Area 2c.GPW IlDF file: raleigh ncsu.IDF Run date: 09-23-2008
Hydrograph Plot
English
Hyd. No. 1
Gaddy 2yr pre 2c
Hydrograph type = Rational
Storm frequency = 2 yrs
Drainage area = 2.4 ac
Intensity = 4.37 in
I-D-F Curve = raleigh ncsu.IDF
Peak discharge = 2.93 cfs
Time interval = 1 min
Runoff coeff. = 0.28
Time of conc. (Tc) = 11 min
Reced. limb factor= 1
Total Volume = 1,937 cult
2.',
2.1
a
CJ 1.
1.(
0.:
3.0
0. 0
1 - Rational - 2 Yr - Qp = 2.93 cfs

i
I
I
' I
0
5 10 15 20 25
/ Hyd. 1
Time (min)
Hydrograph Plot
English
Hyd. No. 2
Gaddy 2yr post 2c
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 2 yrs
= 2.4 ac
= 4.37 in
= raleigh ncsu.IDF
Peak discharge = 4.82 cfs
Time interval = 1 min
Runoff coeff. = 0.46
Time of conc. (Tc) = 11 min
Reced. limb factor = 1
Total Volume = 3,182 cult
2 - Rational - 2 Yr - Qp = 4.82 cfs
I 5 ----
H
/ Hyd. 2
w
1
i
0 5 10 15 20 25
Time (min)

i
III j

3
0
Hydrograph Plot
English
Hyd. No. 3
Area 2 with storage
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Inflow hyd. No. = 2
Max. Elevation = 284.76 ft
Peak discharge
Time interval
Reservoir name
Max. Storage
= 2.33 cfs
= 1 min
= Storage tank
= 1,657 cuft
Storage Indication method used.
Total Volume = 3,182 cult
3 - Reservoir - 2 Yr - Qp = 2.33 cfs
5
I
j / Hyd. 2
I
I
' N
y-
I V
CY
I
I
/ Hyd. 3
i
i
0 50 100 150
Time (min)
4

3 --- i
I
I

I
i
? I
1 ?

i i
0
Hydrograph Plot
English
Hyd. No. 4
Gaddy 10yr pre 2c
Hydrograph type = Rational Peak discharge = 3.81 cfs
Storm frequency = 10 yrs Time interval = 1 min
Drainage area = 2.4 ac Runoff coeff. = 0.28
Intensity = 5.67 in Time of conc. (Tc) = 11 min
I-D-F Curve = raleigh ncsu.IDF Reced. limb factor= 1
Total Volume = 2,517 cuft
1 ?
4 - Rational -10 Yr - Qp = 3.81 cfs
r
3 -- 1- -
I
'
2 --- --? / Hyd. 4 j
CY
;
{
I
i
0
0 5 10 15 20 25
Time (min)
Hydrograph Plot
English
Hyd. No. 5
Gaddy 10yr post 2c
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 10 yrs
= 2.4 ac
= 5.67 in
= raleigh ncsu.IDF
Peak discharge = 6.27 cfs
Time interval = 1 min
Runoff coeff. = 0.46
Time of conc. (Tc) = 11 min
Reced. limb factor= 1
Total Volume = 4,135 cult
j
6 - Rational -10 Yr - Qp = 6.27 cfs
I
H
/ Hyd. 5
a I
I
i
i
0 5 10 15 20 25
I
Time (min)
I
? i
?I I
i
I

0 i

Brookddge
Runoff Cale
Ana
Revised 111112006
r Sohdng for Time of Concentration
Kinematic Wave Theory
r 1`JOFF:r?Ft' GEW
- 1 L Lenoth of overland flow FAMMfeel Surface,Mann •n
ent "D3 II L - Q Mannin s "n" for surface : D"240 SmooftSurfaoe -0:911
SUIP1ES8: Avers awatershed slo ff./ft. Fallow 0.050
erd - .DOWNTOWN-AREAS( .07-0.95 :onstanl el a 1.756 Cultivated -70%R ue 0:080
NEIGHBORHOOD AREAS 0.5-07 N::onsiani m Cu > R -0;170
ant -0.95 RESIDERTA.: Weighted Runoff Coefficient 0.390098 Grass,JS 111 0:150
SINGLE-FAMILY AREAS -0.345 -GR96Q .:_4,240
ent IWAL71 UNITS. DETACHED 04-06 ,.Grass"8ertmda '0:470
nt 0.3991 [ MULTI UNITS; ATTACHED D.C-0.75 Woods'LI Itt' 0 DO
SUBURBAN 4 Woods, Dense =a:80O-
I MWSTPoEL
4.386 LIGHT AREAS 0510,8 (Trail rime of Duration ( (Rainfall Int-ity(IDFI (Calculation of Time of Concentration
HEAVY AREAS O-e-O.D ?r (rnraras) (Ir>hour) tc (rrunums)
'PARKS, CEMEfARIES D.1-0.25 htt ://hdscnws.noaa, ov/hdsc/tdsrorb/nc to hi rd
'P1AY4ROLINDS '02.035 ' - 8.84
RAILROAD YARD AREAS tf 1 9.67
UNIMPROVED ARFAS : :0.1-b 3 rk 1035
fsrRttirs: 11.78
,A3PFil LT ;D 7.095 13.99
'.CONCRETE 0;8:0.1)5 17.24
BRICK '-0:7-0.65 19.73
.DRIVES AND WALKS Y075-0.85 19.95-
':ROJFS .0.75-0.85 29.87
;"vam: 38.40
SANDY -SOIL FLAT 1 2%
SANDY SOIL, AVE., 2 7% .:0.1.0.15 Entar the Rainfall Intensity Values for the Corresponding Times of Duration from the NWS hyperlink provided.
SANDY SOIL STEEP, 7%i 0.15=02 !Select the Tnaf Time of Duration that is a i al to or less than the calculated Time of Concentration, or the Calculauad 1
of Concentration if less than 5 minutes. This is the overland flow component of the Time of Concentration.
Dvedand Flow ?tc lm.u,res)
HEAVY SOIL, FLAT, 2% 0 13-0:17 -
HEAVY SOIL, AVE.;.2-791, - .0.18-0.22 <;. l Calculate the shallow concentrated flow component of the Time of Concentration.
HEAVY. SOIL, STEEP, 7% 0.250.35 <. Calculate the channel flow componem of the Time of Concentration.
'?AGfM:uLT9AU. LAND: ,I Sum these three comporcents. This is the total Time of Concentration.
E FE PAGY<EP SCN.
SMOOTH 0,3-0K 13hallow Concemrited Flow (Channel Flow
'ROUGH 02-0.S
CLLP'17EDRa' Paved
HEAVY SOIL NO CROP -0.3-08 'Flow Len th Flow Len h
HEAVYSOIL WITH CROP 0.2-0 3 910pe 30
SANDY SOIL NU CROP 0,20,4 a.(mnules) 0.0 H mulic Radius
SANDY SOIL WITH CROP '.0:1-025 Unpaved Man * a,,
P187uae IFlow Len h Ic (minmec) 0.0
HEAVY SOIL 0.15.045 rlnia)
SANDY SOIL 0 .OL-i)25 -J-) 0.6•
WOODLANDS x.0,05-0,2.5
Total Time of Concentration ( 10.6
TGH
-` A
NCDENR
v
> I L./W\J? r
o -?
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
LEVEL SPREADER, FILTER STRIP AND RESTORED RIPARIAN BUFFER SUPPLEMENT
This form must be completely filled out, printed and submitted.
DO NOT FORGET TO ATTACH THE REQUIRED ITEMS CHECKLIST AND ALL REQUIRED ITEMS (NEXT WORKSHEET)!
I. PROJECT INFORMATION
Project name Cedar Chest
Contact name Cadl Simmons
Phone number 833-0830
Date September 23, 2008
Drainage area number Area 3
II. DESIGNINFORMATION
For Level Spreaders Receiving Flow From a BMP
Type of BMP Underground Dry Detention
Drawdown flow from the BMP 3.09 cfs
For Level Spreaders Receiving Flow from the Drainage Area Do not complete this section of the worksheet.
Drainage area ft2 Do not complete this section of the worksheet.
Impervious surface area ftz Do not complete this section of the worksheet.
Percent impervious % Do not complete this section of the worksheet.
Rational C coefficient Do not complete this section of the worksheet.
Peak flow from the 1 in/hr storm cfs Do not complete this section of the worksheet.
Time of concentration min
Rainfall intensity, 10-yr storm in/hr Do not complete this section of the worksheet.
Peak flow from the 10-yr storm cfs Do not complete this section of the worksheet.
Where Does the Level Spreader Discharge?
To a grassed bioretention cell? N (Y or N)
To a mulched bioretention cell? N (Y or N)
To a wetland? N (Y or N)
To a filter strip or riparian buffer? Y (Y or N) Please complete filter strip characterization below
Other (specify)
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass 70.00 ft
Width of dense ground cover ft
Width of wooded vegetation ft
Total width 70.00 ft
Elevation at downslope base of level lip 282.50 fmsl
Elevation at top of bank of the receiving water 276.00 fmsl
Slope (from level lip to to top of bank) 9.29 %
Are any draws present? N (Y or N)
Level Spreader Design
Forebay surface area sq ft
Feet of level lip needed per cis 13 ft/cfs
Answer "Y" to one of the following:
Length based on the 1 in/hr storm? N (Y or N)
Length based on the 10-yr storm? Y (Y or N)
Length based on the BMP discharge rate? Y (Y or N)
Design flow 3.09 cfs
Is a bypass device provided? N (Y or N)
Level spreaders must be placed in series.
OK
No forebay is needed.
A bypass device is not needed.
Form SW401-Level Spreader, Fitter Strip, Restored Riparian Buffer-Rev.5 Parts I. and II. Design Summary, page 1 of 2
Length of the level lip 50.00 ft #VALUE!
Are level spreaders in series? N (Y or N)
Bypass Channel Design (if applicable)
Does the bypass discharge through a wetland? (Y or N) Do not complete this section of the worksheet.
Does the channel enter the stream at an angle? (Y or N) Do not complete this section of the worksheet.
Dimensions of the channel (see diagram below): Do not complete this section of the worksheet.
M ft Do not complete this section of the worksheet.
B ft Do not complete this section of the worksheet.
W ft Do not complete this section of the worksheet.
y ft Do not complete this section of the worksheet.
Peak velocity in the channel during the 10-yr storm cfs Do not complete this section of the worksheet.
Channel lining material Do not complete this section of the worksheet.

t
Y
-
t
? -------------
M
M
i B i
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev. 5 Parts I. and II. Design Summary, page 2 of 2
III. REQUIRED ITEMS CHECKLIST
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.
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),
- Forebay (if applicable),
- High flow bypass system,
- Maintenance access,
- Proposed drainage easement and public right of way (ROW), and
- Boundaries of drainage easement.
2. Plan details (1" = 30' or larger) for the level spreader showing:
- Forebay (if applicable),
- High flow bypass system,
- One foot topo lines between the level lip and top of stream bank,
- Proposed drainage easement, and
- Design at ultimate build-out.
J VIC,- r? 3. Section view of the level spreader (1" = 20' or larger) showing:
- Underdrain system (if applicable),
- Level lip,
- Upslope channel, and
- Downslope filter fabric.
4. A date-stamped photograph of the filter strip that clearly shows the type of vegetation that is present.
5. A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized.
C C_- 6. The supporting calculations.
P-C 7. A copy of the signed and notarized operation and maintenance (0&M) agreement.
8. A copy of the deed restrictions (if required).
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev-5 Part III, page 1 of 1
Hydrograph Summary Report
Page 1
Hyd.
No. Hydrograph
type
(origin) Peak
flow
(cfs) Time
interval
(min) Time to
peak
(min) Volume

(cult) Return
period
(yrs) Inflow
hyd(s) Maximum
elevation
(ft) Maximum
storage
(cult) Hydrograph
description
1 Rational 2.43 1 11 1,607 2 - - ----- Gaddy 2yr pre 3
2 Rational 3.90 1 11 2,571 2 - Gaddy 2yr post 3
3 Reservoir 2.18 1 16 2,571 2 2 284.78 1,392 Area 3 with storag
4 Rational 3.16 1 11 2,088 10 - - Gaddy 10yr pre 3
5 Rational 5.06 1 11 3,341 10 - ---- - Gaddy 10yr post 3
6 Reservoir 3.09 1 15 3,341 10 5 285.28 1,639 Area 3 with storag
Proj. file: Area 3.GPW OF file: raleigh ncsu.IDF Run date: 09-23-2008
Hydrograph Plot
English
Hyd. No. 1
Gaddy 2yr pre 3
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 2 yrs
= 2.2 ac
= 4.37 in
= raleigh ncsu.IDF
Peak discharge = 2.43 cfs
Time interval = 1 min
Runoff coeff. = 0.25
Time of conc. (Tc) = 11 min
Reced. limb factor = 1
Total Volume = 1,607 cult
I
1 - Rational - 2 Yr - Qp = 2.43 cfs
j 2.5
i
i
2. j
/ Hyd. 1
C1
1.
I
0.0
j
0 5 10 15 20 25
i
i
Time (min)
t

' •,

i i i
I
50
0
Hydrograph Plot
English
Hyd. No. 2
Gaddy 2yr post 3
Hydrograph type = Rational Peak discharge = 3.90 cfs
Storm frequency = 2 yrs Time interval = 1 min
Drainage area = 2.2 ac Runoff coeff. = 0.4
Intensity = 4.37 in Time of conc. (Tc) = 11 min
I-D-F Curve = raleigh ncsu.IDF Reced. limb factor= 1
Total Volume 2,571 cuft
2 - Rational - 2 Yr - Q - 3.90 cfs
4
i
i
/ Hyd. 2
C
10 15 20 25
Time (min)

2 i
i
i

1 I
I
I
0
0 5
Hydrograph Plot
English
Hyd. No. 3
Area 3 with storage
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Inflow hyd. No. = 2
Max. Elevation = 284.78 ft
Peak discharge
Time interval
Reservoir name
Max. Storage
= 2.18 cfs
= 1 min
= tank storage
= 1,392 cuft
Storage Indication method used.
Total Volume= 2,571 cult
3 - Reservoir - 2 Yr - Qp = 2.18 cfs
i
- /Hyd. 2
j v 3
CY I
?
2
/ Hyd. 3
0
0 50 100 150
i
Time (min)
Hydrograph Plot
English
Hyd. No. 4
Gaddy 10yr pre 3
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 10 yrs
= 2.2 ac
= 5.67 in
= raleigh ncsu.IDF
Peak discharge = 3.16 cfs
Time interval = 1 min
Runoff coeff. = 0.25
Time of conc. (Tc) = 11 min
Reced. limb factor = 1
Total Volume = 2,088 cult
Hydrograph Plot
English
Hyd. No. 5
Gaddy 10yr post 3
Hydrograph type
Storm frequency
Drainage area
Intensity
I-D-F Curve
= Rational
= 10 yrs
= 2.2 ac
= 5.67 in
= raleigh ncsu.IDF
Peak discharge = 5.06 cfs
Time interval = 1 min
Runoff coeff. = 0.4
Time of conc. (Tc) = 11 min
Reced. limb factor = 1
Total Volume = 3,341 cult
5 - Rational -10 Yr - Qp = 5.06 cfs
I
/ Hyd. 5 j
d
i
i
0 5 10 15 20 25
Time (min)

i
t

0 i

Hydrograph Plot
English
Hyd. No. 6
Area 3 with storage
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Inflow hyd. No. = 5
Max. Elevation = 285.28 ft
Peak discharge
Time interval
Reservoir name
Max. Storage
= 3.09 cfs
= 1 min
= tank storage
= 1,639 cuft
Storage Indication method used.
Total Volume = 3,341 cult
6 - Reservoir -10 Yr - Qp = 3.09 cfs
6
i i
/Hyd. 5
i
r
i
w
V I
d
!
I
/ Hyd. 6
I 0 50 100 150
Time (min)
i

5 i
- j
!
3

2 I
I I

0 I
Reservoir Report Page 1
English
Reservoir No. 1 - tank storage
Pond Data
Bottom area = 500.0 sqft Side slope = 0.0:1 Bottom elev. = 282.00 ft Depth = 3.50 ft
Stage / Storage Table
Stage Elevation
ft ft
0.00
0.35
0.70
1.05
1.40
1.75
2.10
2.45
2.80
3.15
3.50
282.00
282.35
282.70
283.05
283.40
283.75
284.10
284.45
284.80
285.15
285.50
Contour area Incr. Storage Total storage
sqft cuft cuft
500 0 0
500 175 175
500 175 350
500 175 525
500 175 700
500 175 875
500 175 1,050
500 175 1,225
500 175 1,400
500 175 1,575
500 175 1,750
Culvert / Orifice Structures
[A]
Rise in = 18.0
Span in = 18.0
No. Barrels = 1
Invert El. ft = 282.00
Length ft = 20.0
Slope % = 1.00
N-Value = .013
Orif. Coeff. = 0.60
Multi-Stage = ----
[I3] [C] [D]
6.0 8.0 0.0
6.0 8.0 0.0
1 1 0
282.00 284.00 0.00
1.0 1.0 0.0
1.00 1.00 0.00
.013 .013 .000
0.60 0.60 0.00
Yes Yes No
Weir Structures
[A] [B] [C] [D]
Crest Len ft = 0.0 0.0 0.0 0.0
Crest El. ft = 0.00 0.00 0.00 0.00
Weir Coeff. = 0.00 0.00 0.00 0.00
Eqn. Exp. = 0.00 0.00 0.00 0.00
Multi-Stage = No No No No
Tailwater Elevation = 0.00 ft
Stage / Storage / Discharge Table
Note: All ouHlows have been analyzed under inlet and outlet control.
Stage Storage Elevation CIv A CIv B CIv C CIv D Wr A Wr B Wr C Wr D Discharge
ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.00 0 282.00 0.00 0.00 0.00 0.00
0.35 175 282.35 0.65 0.10 0.00 --- - --- -- --- 0.10
0.70 350 282.70 2.20 0.57 0.00 - - -- - --- 0.57
1.05 525 283.05 3.60 0.78 0.00 - -- -- - -- 0.78
1.40 700 283.40 4.61 0.94 0.00 --- --- - - --- 0.94
1.75 875 283.75 6.97 1.08 0.00 - - -- - - 1.08
2.10 1,050 284.10 9.30 1.20 0.02 -- - --- --- -- 1.22
2.45 1,225 284.45 11.09 1.31 0.17 --- - -- - -- 1.48
2.80 1,400 284.80 12.18 1.38 0.85 - - -- --- -- 2.23
3.15 1,575 285.15 13.18 1.43 1.52 --- - - --- --- 2.95
3.50 1,750 285.50 14.11 1.50 1.82 - - -- --- - 3.32
_ /Ot ? x /Z?f7' x ?I! ?' /05 Gam" = ?BCP q?//u??

6?? ? 41,-? lay'71 4/.) ;e6, ?ia, /,/,4,7 Vcyl??
6 ",/ V/ 4-17 16191/? 1
6? A-O- l Z /V *?
Technical Guidance: Stormwater Treatment Credit for Rainwater Harvesting Systems September 22, 2008
Cistern Overflow Pipe Sizing:
Table 1: Determining overflow pipe diameter for a given captured roof
area (ft2) for select cities
Overflow Pi a Dia.
city '/2' 1 " 2" 2.5" 3" 4"
Asheville 38 157 720 1,170 1,740 3,32
Boone 33 144 631 1,020 1,530 2,91
Charlotte 37 155 710 1,150 1,720 3,28
Elizabeth City 32 132 603 981 1,460 2,78
Fayetteville 33 142 624 1,010 1,510 2,88
Franklin 38 165 724 1,170 1,760, 3,34
Greenville 31 131 598 973 1,450 2,76
Raleigh 38 160 715, 1,160 1,74 3,30
Rock Mount 36 150 687 1,110 1,670 3,17
Wilmington 26 110 498 810 1,210 2,300
Winston-Salem 40 165 756 1,230 1,830 3,49
Modified from Jones, M. P. and Hunt, W. F.

Gutter Sizing:
Table 2: Determining Gutter size for a given gutter slope and captured roof area (ft2) for select cities
Gutter Size for 1/2% Gutter Sloe Gutter Size f or 1% Gutter Slope
City 3" 4" 5" 6" 3" 4" 5" 6"
Asheville 216 457 794 1,210 305 648 1,110 1,720
Boone 189 401 697 110-70- 267 568 980 1,510
harlotte 213 451 784 1,200 301 640 1,100 1,700
Elizabeth City 181 383 665 1,020 255 543 936 1,440
Fa etteville 187 397 689 1,050 264 562 969 1,490
Franklin 217 460 799 1,220 307 652 1,120 1,730
reenville 179 380 660 1,010 253 538 929 1,430
alei h 214 454 789 1,210 303 644 1,110 1,710
ock Mount 206 436 758 1,160 291 618 1,060 1,640
ilmin ton 149 316 550 844 211 449 773 1,190
inston-Salem 227 480 833 1,280 320 680 1,170 1,810
Modified from Jones. M_ P_ and Hunt_ W. F
/Z,/o (O
Page 5 of 8
• Technical Guidance: Stormwater Treatment Credit for Rainwater Harvesting Systems September 22, 2008
Gutter Downspout Sizing:
Table 3: Determining Gutter downspout
diameter for a given captured roof area (ft2) for
select cities
Gutter Downspout Dia.
City 2" 3" 4"
sheville 914 2,790 5,84
oone 802 2,450 5,1201
harlotte 902 2,750 5,76
lizabeth City 765 2,340 4,89
Fa etteviiie 793 2,420 5,06
Franklin 920 2,810, 5,87
reenville 759 2,320 4,85
Ralei h 908 70 5,80
ock Mount 872 r,6 0 5,57
ilmin ton 632 1,930 4,04
inston-Salem 960 2,930 6,1301
Modified from Jones, M. P. and Hunt, W. F.
Operation & Maintenance:
s/
3 //
Important maintenance procedures:
- The roof area will be maintained to reduce the debris and sediment load to the system. Excess
debris can clog the system and lead to bypass of the design storm, and reduced reuse volume.
- To ensure proper operation as designed, a licensed Professional Engineer, Landscape Architect,
or other qualified professional will inspect the system annually.
- The system components will be repaired or replaced whenever they fail to function properly.
- If the outlet is metered, use must be recorded at a minimum of monthly. These records shall be
kept on site for inspection by DWQ.
The system will be inspected by the owner/ operator at least monthly and within 24 hours after each
rain event. Records of operation and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall be repaired
immediately.
Page 6 of 8
Hydrograph Plot
English
Hyd. No. 1
Lot 100yr post
Hydrograph type
Storm frequency
Drainage area
Intensity
1-D-F Curve
= Rational
= 100 yrs
= 0.3 ac
= 8.98 in
= raleigh ncsu.IDF
Peak discharge = 1.26 cfs
Time interval = 1 min
Runoff coeff. = 0.54
Time of conc. (TO = 5 min
Reced. limb factor= 1
Total Volume = 378 cult
1 - Rational -100 Yr - Qp =1.26 dfs
1.5
1.0
/ Hyd. 1
CY
0.5
0.0
0 2 4 6 8 10
Time (min)
Hydrograph Plot
English
Hyd. No. 2
Hydrograph type = Reservoir Peak discharge = 0.00 cfs
Storm frequency = 100 yrs Time interval = 1 min
Inflow hyd. No. = 1 Reservoir name = rain garden
Max. Elevation = 274.49 ft Max. Storage = 378 cuft
Storage MWic bw method used.
Total Volume = 0 cult
2 - Reservoir -100 Yr - Max. El. = 274.49 ft
275.0-
274.8-
r- 274.6
`V
w`
W
W
274.4
27
27
0 5 10 15 20 25
Time (hrs)

4
2
.
4
0
.

a MFUM we Mtfi U.Lb ac
Dixharge
Ifs Peals Flow
Period Vebcity (fpe) Area (sq R.] Hydraric
Raduot) Normal

D
3 0.1 1.75 0.74 0.23 (136
Rods Riprap
S = 0.1000
1 Vf&.4w .OO R 1
Not to Scab
Reach Material T Phase V T Sol Toe Manmg's'n P aible Calalatad Safety Remarks
Staple Pattern pas: V D Sheer Stress (paf) Shear Stress Facto
Straight Rack Riiprap 0.100 267 223 1.19 STABLE
Din