20081095 Ver 2_Stormwater Info_20090227

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r:) ,r;,:;:- r"A:ir lr=-."i ...", /,':; f ---. '-
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Uti 1011
FEB .2 7 20G.9 L,

HORVATH

DENR - WATER Q['AUT'r
WETl.AJ~DS AND STORMWATER BRJI}lC:-:

ASSOCIATES

CIVIL ENGINEERS PLANNERS LANDSCAPE ARCHITECTS

Greenway
Level Spreader Calculations
January 7, 2009
Job 0511

\D)g@~uWg~
\;.~
ij>~ JAN 2 8 Z009

Dt.NR . WAYt:F ~~~r BRftNCH
WETLANDS ~NO SlORM~ f"

North Curolina Tennessee

16 Consultant Place, Suite 201 537 Market Street Suite LL20
Durham, NC 27707 Chattanooga, TN 37402
P 919.490.4990 / f 919.490.8953 P 423,266.4990 / f 423.266.5700

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GREENWAY
LEVEL SPREADER DESIGN NARRATIVE
PLUNGE POOL DESIGN NARRATIVE

Greenway
Chandler Road
Durham, North Carolina
Horvath Associates Project #: 0511.2
June 6, 2007
Revised August 6, 2007
Revised January 7, 2009

Prepared for: Cimland, LLC
18 West Colony Place, Suite 140
Durham, North Carolina 27705
[phone]

Prepared by: Horvath Associates, P .A.
Engineers - Planners - Landscape Architects
P.O. Box 51806
Durham, North Carolina 27717
[phone]

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TABLE OF CONTENTS

1. NARRATIVE
2. NC DWQ LEVEL SPREADER SUPPLEMENTS
3. DESIGN SUMMARIES
4. VELOCITY DISSIPATOR DESIGN
5. LS 2 LOW FLOW ORIFICE CALCULATIONS
6. LEVEL SPREADER AERIAL PHOTOS
7. PHOTOS OF FILTER STRIPS
8. OPERATIONS AND MAINTENANCE AGREEMENTS

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NARRATIVE

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GREENWAY
LEVEL SPREADER DESIGN NARRATIVE
PLUNGE POOL DESIGN NARRATIVE

General Description

Greenway is a proposed multi-family project consisting of town homes,
apartments, and the associated streets and utilities. The 14.33-acre site is
located north of NC Hwy 98, off Chandler Road, and between Chandler Road
and Little Lick Creek Tributary A. The site is located in the Neuse River Basin and
the F/ J-B watershed protection district. The development plan for this project
predates watershed protection rules and certain flood plain ordinances. For this
reason, the project is exempt from 85% TSS removal and watershed protection
buffers. Nitrogen loading calculations and l-year peak flow calculations are
included in the stormwater impact analysis, along with analysis of the peak flow
resulting from the 2- and 1 a-year storm events.

As explained in the SIA, detention of the 1-, 2-, and 1 a-year storm events is
unnecessary, because lack of detention will have no negative impact on the
site.

This submittal is part of a construction document-level design package. This
narrative and calculations describe the design of the two storm pipe outlets
associated with the Greenway development.

Revisions

· Storm CAD was previously used to size the low flow pipe discharging into
the level spreader. HydroCAD is now utilized to size the pipe and it is
specified as a la-inch diameter DIP.

· Photos have been added that clearly demonstrate the filter strips for both
the level spreader and plunge pool consist of dense vegetation. The level
spreader length was designed based on a forested filter strip, therefore its
length will be more than adequate for a filter strip with dense ground
cover.

· The topography on sheet C41 a has been updated based on additional
survey shots taken in the field from the level spreader and plunge pool to
the top of stream bank.

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Site Hydrology

Consult the most recently approved stormwater impact analysis, which is
included with the design package submittal.

Two level spreaders are designed according to North Carolina Division of Water
Quality's "Level Spreader Design Guidelines, Final Version, effective date
January 1,2007." LS 1 is located near the northeastern property corner, and LS 2
is located near the southeastern property corner. Level spreaders are the best
stormwater management practice because they will improve water quality
without significantly affecting the existing drainage patterns. The diffuse flow
discharge will also reduce potential erosion.

The first, LS 1, is a preformed scour hole, and the second, LS 2, incorporates a
design that utilizes a level spreader with an upstream bypass structure. This
structure, CB 65, separates the flow into two hydraulically separate outlets: a
level spreader and a velocity dissipator. LS 1 is an on-line device, so it will route
all storms. LS 2 will handle the runoff resulting from the one inch per hour storm,
which is the water-quality design event for this stormwater BMP. Additional flow
will be diverted using the bypass structure; the overflow will pass through a
velocity dissipator and into the adjacent stream buffer or wetlands.

level Spreader Design

The level spreaders (LS 1 & 2) are located at the end of curb and gutter storm
drain networks. Both level spreaders outlet on to extremely flat slopes, due in
part to their proximity to the floodway.

LS 1 will use a preformed scour hole to dissipate flow. The scour hole consists of a
riprap plunge pool surrounded by a channel reinforced with turf reinforcement
matting (TRM). The riprap is sized using the runoff resulting from the 1 O-year storm,
as per NC DENR guidelines. The reinforced channel is sized so that the required
level spreader length is measured along the outside crest of the channel. Plan
details are shown on sheet C41 o.

LS 2 will utilize a bypass structure with a low-flow orifice and a high-flow orifice.
The high-flow orifice will pass lower-frequency storm events into a velocity
dissipator, which will discharge into the floodway. The low-flow orifice will route
the l"/hr water quality storm through an 8"-diameter ductile iron pipe section
and into a riprap fore bay, which is sized at 0.2% of the contributing impervious
area. The forebay will overflow into an adjacent grass channel, with a concrete
lip set at a constant elevation to distribute and disperse the flow. Plan details are
shown on sheet C41 O.

Soil tests were not performed at the proposed level spreader location, so

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infiltration has not been incorporated into design calculations. However,
infiltration is expected to be minimal.

Plunae Pool Velocity Dissipator Desian

The outfalls at HW 1 &2 will utilize plunge pool velocity dissipators. This structure
will reduce the velocity and sediment transport ability of the outlet flows. The
plunge pools were designed using the NYDOT method outlined in the NCDENR
Erosion and Sediment Control manual. The design storm is the 1 Q-year rainfall
event. Hydraulic calculations to determine the outlet flow were performed using
StormCAD pipe modeling software, which uses the Rational Method.

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MethodolOQV

· The cover conditions downstream of the level spreader are a mixture of forested
and dense ground cover vegetation or grassed floodplain. The "Level Spreader
Design Guidelines" specifies a level spreader length of 65, 50, or 40 feet per 1 cfs
of discharge resulting from the 1" /hr storm event based on a vegetated buffer
depth of 50, 100, and 150 feet, respectively, and 13 feet per cfs of grass buffer.
The attached photos show the grassed floodplain at LS 2.

· Design calculations are summarized in the appended Level Spreader Design
Summary.

· The peak flows were derived using StormCAD v05.06.012.00 software, which uses
the Rational Method. Runoff coefficients (C values) were determined according
to the site plan and anticipated lot impervious area, and a time of
concentration of 5 minutes was assumed in all cases.

· The low flow pipe discharging to the level spreader LS 2 is sized using HydroCAD.
· Soils are all HSG 'D' soils, according to the NRCS Soil Survey Atlas of Durham
County.

· Consult the most recently approved SIA for more information on hydrology.

· Topography in the vicinity of the level spreaders was developed using a
combination of spot elevations from the original field survey of the entire site
and spot elevations that were taken from the level spreaders to the top of bank
after a DWQ request for more information.

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NC DWQ LEVEL SPREADER
SUPPLEMENTS

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

II. PROJECT INFORMATION
Project name
Contact name
Phone number
Date
Drainage area number

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fJ /, () N G[. fOb t-

AVA
HCDENR

Greenway
John Schrum
[phone]
September 29, 2008
4.2

L:5 /

r1~Of V,Afl'-9oC-
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I". DESIGN INFORMATION
For level Spreaders Receiving Flow From a BMP
Type of BMP
Drawdown flow from the BMP

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 inlhr storm
Time of concentration
Rainfall intensity, 1 O-yr storm
Peak flow from the 1 O-yr storm

56,628,00
31,800,00
56,16
0,67
0,87
5,00

6,29

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)

N
N
N
Y

ft
ft
71.00 ft
71.00 ft
300,60 fmsl
299,00 fmsl
2.25 % OK
N (Y orN) OK
Jt L~ 1. I~ 1\ PREFOR"",&.D SUJVJ2.
168.00 sq ft OK H OL-/~ . ~fE f)f5Utv' tJtll1 t1N< Y
65 Wcfs fO~ f)ETA/L-~.
N (Y orN)
Y (Y orN)
N (Y orN)
5,36 cfs There is too much flow to be handled by a level spreader,
N (YorN) A bypass device is not needed.

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 DesignJt"
Forebay surface area
Feet of level lip needed per cfs
Answer 'V' to one of the following:
Length based on the 1 inlhr storm?
Length based on the 1 O-yr storm?
Length based on the BMP discharge rate?
Design flow
Is a bypass device provided?

Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.5

ff
ff
%

cfs

min
7.22 in/hr
cfs

(YorN)
(YorN)
(YorN)
(Y or N) Please complete filter strip characterization below.

Parts I. and II. Design Summary, page 1 of 2

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Length of the level lip
Are level spreaders in series?

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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 1 O-yr storm
Channel lining material

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58.00
N

ft
(Y or N)

(YorN)
(YorN)

ft
ft
ft
ft
efs

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Level spreader is not long enough. 1-' -t l-1 -i' /7

Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.
Do not complete this section of the worksheet.

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Fonn SW401-Level Spreader. Fitter Strip, Restored Riparian Buffer-Rev,5

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Parts I. and II. Design Summary, page 2 of 2

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111I. REQUIRED ITEMS CHECKLIST

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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.

Initials
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Pagel Plan
Sheet No.
(~/ 1/ ()

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uf 1()

KEr'oP--{
):.c(() R T

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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), ,f; D ~ 1
- 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" = 3D' 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.

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,

6, The supporting calculations,

7, A copy of the signed and notarized operation and maintenance (O&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

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

II. PROJECT INFORMATION
Project name
Contact name
Phone number
Date
Drainage area number

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A\TA.
NCDENR

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L GVG-v 5f({~/Jf)~e J.

0' WAT~".9

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D '<

Greenway
John Schrum

[phone]
September 29. 2008
3.2

III. DESIGN INFORMATION
For level Spreaders Receiving Flow From a BMP
Type of BMP
Drawdown flow from the BMP

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For Level Spreaders Receiving Flow from the Drainage Area
Drainage area
I mpervious surface area
Percent impervious
Rational C coefficient
Peak flow from the 1 in/hr storm
Time of concentration
Rainfall intensity, 1 O-yr storm
Peak flow from the 1 O-yr storm

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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)

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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?

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Level Spreader Design
Forebay surface area
Feet of level lip needed per cfs
Answer "V" to one of the following:
Length based on the 1 inlhr storm?
Length based on the 1 O-yr storm?
Length based on the BMP discharge rate?
Design flow
Is a bypass device provided?

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Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev,5

cfs

183,387.60
95,832.00
52.26
0,64
2,69
5.00

ft2
ft2
%

cfs

19.45

min
7.22 inlhr
cfs

(YarN)
(Y orN)
(Y orN)
(Y or N) Please complete filter strip characterization below.

Y

50,00 ft
fl
ft
50,00 ft
299,50 fmsl
297,00 fmsl
5,00 % OK
N (Y or N) OK
192,00 sq ft OK
13 flIcfs
Y (YorN)
(Y orN)
(YarN)
2.71 cfs
Y (YarN) OK

Parts I. and II. Design Summary, page 1 of 2

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Length of the level lip
Are level spreaders in series?

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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 1 O-yr storm
Channel lining material

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36.00 ft Level spreader length OK.
N (Y orN)
N (Y orN)
Y (Y orN)
ft
ft
ft
ft
cfs

w

y

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:4
,
,
.

B

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Form SW401-Level Spreader, Filter Strip. Restored Riparian Buffer-Rev.S

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Parts I. and II, Design Summary. page 2 of 2

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111I. 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.

If/ORT
If/oil
/
/1/~~

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Initials
,~2h'
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(11/"),
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Pagel Plan
Sheet No.
c4/tJ

c1/ti

{/1 It,

f! f ftie T
,~
{11 ?'

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), 'Sp ~1.
- 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.

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,

6. The supporting calculations,

7. A copy of the signed and notarized operation and maintenance (O&M) agreement.

8, A copy of the deed restrictions (if required).

Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev,5

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Part III, page 1 of 1

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DESIGN SUMMARIES

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0511.2 Level Spreader Design Summary.xls
LS 1

Preformed Scour Hole Design Summary

Adapted from DWQ Level Spreader Design Guidelines, Final Version, eff. Jon 1, 2007

Preformed Scour Hole ID
End Section ID
End Section Diameter (in)
Drainage Point (see SIA)
Drainage Area (acres)
Composite Rational 'e' value
(see storm pipe design report)
1 "jhr flow (ets)
Max. Allowable 10-Year Discharge for 18" Pipe (ets)
1 O-year storm event peak flow (ets)

LS 1
HW1
18
DP 4.2
1.30

0.67

0.87
10.00

"'~.hi

Cover type
Vegetated buffer distance to stream (ft)

grassed
71

Min. Allowable Base Width of Scour Hole (ft)
Provided Base Width of Scour Hole (ft)

4.5
8

John Schrum, PE
10/7/2008

Note: 'LS l' is a plunge pool with a level spreader apron as a NC DWQ design option

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0511.2 Level Spreader Design Summary.xls
LS2

John Schrum, PE
10/7/2008

Level Spreader Design Summary
Adapted from DWQ Level Spreader Design Guidelines, Final Version, eff. Jon 1, 2007

Level Spreader ID

End Section ID

Drainage Point (see SIA)

Drainage Area (acres)

Composite Rational'C' value
(see storm pipe design report)

1 "/hr flow (cfs)

1 O-year storm event peak flow

LS 2
HW2
DP 3.2
4.21

0.64

#/lit ~.(,q
~11.45

Cover type

Vegetated buffer distance to stream (ft)

Length of level spreader per 1 cfs (ft/cfs)

Required level spreader length (ft)

Provided level spreader length (ft)

grassed

50
13
35
36

Impervious area to level spreader (sq ft)
Required forebay size (0.2% imperv.) (sq ft)
Provided forebay area (sq ft)
Crest Elevation

95,832
192
200
299.50

Note: 'LS l' is a plunge pool with a level spreader apron as a NC DWQ design option

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0511,2 C-Value Calcs,xls

1 0/8/2008
Matt Jones

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Project:
Date:

Greenway
10/8/2008

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Calculations for Runoff Coefficients
Note: Type C Soils were usedfor the calculations, Thefollowing runoff coefficients are for
the 2 and] 0 year storms. Multiply by a factor of ],] to obtain the 25 year coefficients.

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Runoff Coefficient = 0.95 x (Impervious Area SF / Drainage Area SF) +
0.30 x (Pervious Area SF / Drainage Area SF)

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Example CB50 = 0.95 x (1,742 SF / 2,178 SF) + 0.30 x (436 /2,178) = 0.82
Imperv. Area= 0.95 Pervious Area =

0.30 Assuming "e" soils

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Inlet # Outfall Drainal!:e Drainal!:e Imnervious Imnervious Imnervious Imnervious Pervious Pervious Pervious Runoff Runoff
BMP ID Area Area (SF) Surface Surface Surface Surface Surface Surface Surface Coefficient Coefficient
(Acres) Area Area (SF) Area (%) =0.95 * % Area (SF) Area (%) =0.30 * % Imn+ Perv. 25YR
(Acres) 10vr
CB50 LS 2 0.05 2,178 0.04 1,742 80% 0.76 436 20% 0,06 0.82 0.90
RCCB52 L82 1.00 43,560 0.22 9,583 22% 0,21 33,977 78% 0,23 0.44 0.49
CB53 LS2 0.12 5,227 0,06 2614 50% 0.48 2,614 50% 0.15 0.63 0.69
CB54 LS 2 0,04 1,742 0,02 871 50% 0.48 871 50% 0.15 0,63 0,69
CB55 L82 0.13 5,663 0.04 1,742 31% 0.29 3,920 69% 0,21 0,50 0.55
CB56 L82 0,07 3,049 0,04 1,742 57% 0,54 1307 43% 0.13 0,67 0,74
CB57 LS 2 0,02 871 0.01 436 50% 0.48 436 50% 0.15 0,63 0.69
CB58 L82 0.05 2,178 0.04 1,742 80% 0.76 436 20% 0,06 0.82 0,90
CB59 LS 2 0.15 6,534 0.11 4,792 73% 0.70 1,742 27% 0,08 0.78 0,85
CB60 L82 0.11 4,792 0,08 3,485 73% 0,69 1,307 27% 0,08 0,77 0.85
CB61 LS 2 0.05 2,178 0.04 1742 80% 0.76 436 20% 0,06 0.82 0,90
RCCB62 L82 0,75 32,670 0.39 16,988 52% 0.49 15,682 48% 0.14 0,64 0,70
CB63 L82 0,05 2,178 0.04 1,742 80% 0.76 436 20% 0,06 0.82 0.90
CB64 L82 0,05 2,178 0.04 1,742 80% 0.76 436 20% 0,06 0.82 0,90
CB65 LS 2 0.04 1,742 0,03 1,307 75% 0,71 436 25% 0,08 0.79 0.87
CB66 L82 0.13 5,663 0.07 3,049 54% 0,51 2,614 46% 0.14 0,65 0,72
CB67 LS 2 0,22 9,583 0.11 4.792 50% 0.48 4,792 50% 0.15 0,63 0.69
RL67 L82 0,11 4,792 0.11 4,792 100% 0,95 0 0% 0,00 0,95 1.05
CB68 L82 0,16 6,970 0,11 4,792 69% 0.65 2,178 31% 0.09 0.75 0,82
RCCB69 LS 2 0.41 17,860 0.25 10,890 61% 0,58 6,970 39% 0.12 0.70 0,77
CB72 LS 2 0.19 8,276 0,11 4,792 58% 0,55 3,485 42% 0,13 0,68 0.74
CB73 L82 0.23 10,019 0.16 6,970 70% 0,66 3,049 30% 0,09 0.75 0.83
RL73 LS2 0,08 3,485 0,08 3,485 100% 0.95 0 0% 0.00 0.95 1.05
CB75 LS 1 0,03 1,089 0,02 871 80% 0,76 218 20% 0.06 0,82 0,90
CB76 LS 1 0.28 12,197 0.13 5,663 46% 0.44 6,534 54% 0.16 0.60 0,66
CB77 L81 0.10 4,356 0,08 3,485 80% 0.76 871 20% 0.06 0.82 0,90
CB79 LS 1 0.07 3,049 0,04 1,742 57% 0,54 1,307 43% 0,13 0,67 0,74
CB80 L81 0,05 2,178 0.04 1,742 80% 0.76 436 20% 0.06 0.82 0,90
CB81 L81 0,25 10,890 0.14 6,098 56% 0,53 4,792 44% 0,13 0,66 0,73
CB82 LS 1 0,25 10,890 0.19 8,276 76% 0.72 2,614 24% 0.07 0.79 0,87
RCCB86 L81 0,27 11,761 0,09 3,920 33% 0.32 7,841 67% 0,20 0,52 0.57

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LS 1
Total Area to LS 1 =
Impervious Area to LS 1 =
Composite C- Value =

1.30
0.73
0.67

Acres

Acres

LS2
Total Area to LS 2 =
Impervious Area to LS 2 =
Composite C- Value =

4.21
2.20
0.64

Acres

Acres

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VELOCITY DISSIPATOR DESIGN

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051 i.2 Level Spreader Design Summary
HW1

Ben Thayer, EI
6/5/2007

Velocity Dissipator Calculations Vi / PIPIES.EXIE
NRCD Land Quality Section - Pipe Design

Entering the following values will provide you with the expected outlet
velocity and depth of flow in a pipe, assuming the Mannings roughness
number is constant over the entire length of the pipe.

10-Year Outflow, Q (cfs) =
Slope, S (%) =
Pipe Dia., D (in.) =
Manning's n Value =

Flow Depth (ft.)
Velocity, V (ft/s)

5.36
8.00
18
0.013

~'" -'" ~
(J J'l ~

75

NRCD Land Quality Section
NYDOT Dissipator Design Results

Pipe Dia., Do (ft.) = 1.50
Outlet Velocity, V 0 (fps) = 12.7 5
Apron Length, LA (ft.) = 0

Average Dia. Stone Thickness
(inches) Class (inches)
4 A 12
8 B 18
>> 10 1 24 <<
14 2 36
Width,W = LA + Do Thickness = 1.5 * DMAX
Width, W = 13.5 ft.
SAY: 14.0 ft.
fiNAl DIMENSIONS:
Length, L (ft.) = 12.0
Width, W (ft.) = 14.0
Depth, D (in.) = 24 (NCDENR Erosion & Sed. Cant. Manual ~8.06.6)
Stone Class = 1 (NCDOT Std. S 1042)

*Cells in red denote required inputs from PIPES.exe outputs

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051'\ ,2 Level Spreader Design Summary
HW2

Ben Thayer, EI
6/5/2007

\fe~odtv Dissipater Calcuraftiens w/ PIPIES.IEXE
NRCD Land Quality Section - Pipe Design

Entering the following values will provide you with the expected outlet
velocity and depth of flow in a pipe, assuming the Marinings roughness
number is constant over the entire length of the pipe.

10-Year Outflow, Q (efs) =
Slope, S (%) =
Pipe Die., D (in.) =
Manning's n Value =

16.11
8.00
24
0.013

Flow Depth (fL)
Velocity, V (ft/s)

:"1 J "
\l.'f) c)

'1 t:er'~:7

NRCD Land Quality Section
NYDOT Dissipator Design Results

Pipe Dia., Do (ft.) =
Outlet Velocity, V 0 (fps) =
Apron Length, LA (ft.) =

2.00
16.97

"" Il
L)

Average Dia. Stone Thickness
(inches) Class (inches)
4 A 12
8 B 18
>> 10 1 24 <<
14 2 36
Width,W = LA + Do Thickness = 1.5 * DMAX
Width, W = 18.0 ft.
SAY: 18.0 ft.
F!NAl DIMENSIONS:
Length, L (ft.) = 16.0
Width, W (ft.) = 18.0
Depth, D (in.) = 24 (NCDENR Erosion & Sed. Cant. Manual ~8.06.6)
Stone Class = 1 (NCDOT Std. s 1 042)

*Cells in red denote required inputs from PIPES.exe outputs

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LS 2 LOW FLOW ORIFICE
CALCULATIONS

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(Subcav
\'--.-.J

Bypass CB65 (To
HW2/LS2)

I--i
IReach!
L-.'

/\
/Pond\
L_~____~__...i

Drainage Diagram for 0511.2 Bypass Design
Prepared by Horvath Associates, PA 8/6/2007
HydroCAD@7,10 sIn 003899 @2005 HydroCAD Software Solutions LLC

~

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S:\Drawings\05\0511\Project Calcs\Greenway (Phase 2)\HydroCAD Bypass Design\
0511.2 Bypass Design Type 1/24-hr Water Quality Rainfall=1.00"
Prepared by Horvath Associates, P.A. Page 2
HydroCAD@ 7.10 sin 003899 @ 2005 HydroCAD Software Solutions LLC 8/6/2007

Subcatchment 1 S: TO CB65

Runoff =

2.72 cfs @ 11.96 hrs, Volume=

0.132 af, Depth> 0,79"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs
Type II 24-hr Water Quality Rainfall=1.00"

Area (ac) CN Description
2.010 98 Impervious Area, Onsite

Tc Length
(min) (feet)
5.0

Slope Velocity Capacity Description
(Nfl) (Nsec) (cfs)

Direct Entry,

Subcatchment 1 S: TO CB65

Hydrograph

3--

2'

Type II 24-hr Water Quality
Rainfall=1.00"
Runoff Area=2.010 ac
Runoff Volume=O.132 af
Runoff Depth>O.79"
Tc=5.0 min
CN=98

.!!1
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........._'--.,~"-~-~._------

.........

-----~_...>...,-----"'--<.-

o
10 11

12
Time (hours)

13

1- Runoff~

14

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S:\Drawings\05\0511 \Project Calcs\Greenway (Phase 2)\HydroCAD Bypass Design\
0511.2 Bypass Design Type 1/24-hr Water Quality Rainfal/=1.00"
Prepared by Horvath Associates, P.A. Page 3
HydroCAD@ 7.10 sIn 003899 @ 2005 HydroCAD Software Solutions LLC 8/6/2007

Time Precip. Excess
(hours) (inches) (inches)
0.00 0.00 0.00
0.50 0.01 0.00
1.00 0.01 0.00
1,50 0.02 0.00
2.00 0.02 0.00
2.50 0.03 0.00
3.00 0.03 0.00
3.50 0.04 0.00
4.00 0.05 0.00
4.50 0.06 0.00
5.00 0.06 0.00
5.50 0.07 0.00
6.00 0,08 0.01
6,50 0.09 0.01
7.00 0.10 0.01
7.50 0.11 0.02
8.00 0.12 0.02
8.50 0.13 0.03
9.00 0.15 0.04
9.50 0.16 0.05
10.00 0.18 0.06
10.50 0.20 0.07
11.00 0.24 0.09
11,50 0.28 0.13
12.00 0.66 0.47
12.50 0.73 0.54
13.00 0.77 0.57
13,50 0.80 0.60
14.00 0.82 0.62
14.50 0,84 0.63
15.00 0.85 0.65
15.50 0.87 0.66
16.00 0.88 0.68
16.50 0.89 0.69
17.00 0.90 0.70
'17.50 0.91 0.71
18.00 0.92 0,71
18.50 0.93 0.72
19.00 0.94 0.73
19.50 0.95 0,74
20.00 0,95 0.74
20.50 0.96 0.75
21.00 0.96 0.76
21.50 0.97 0.76
22.00 0.98 0.77
22.50 0.98 0,77
23.00 0.99 0,78
23.50 0.99 0.79
24.00 H)D 0.79

Hydrograph for Subcatchment 15: TO CBS5

Runoff
(cfs)
0.00
0,00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.Q1
0.01
0.01
0.01
0.02
0,02
0,02
0,03
0.04
0.04
0.05
0.07
0,10
0.18
2.27
0.20
0.13
0.10
0.07
0.07
0,06
0.05
0.05
0.04
0.04
0.04
0.04
0.03
0.03
0.03
0.03
0.03
0.02
0,02
0.02
0.02
0.02
,0.02
0.02

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S:\Drawings\05\0511\Project Calcs\Greenway (Phase 2)\HydroCAD Bypass Design\
0511.2 Bypass Design Type 1/24-hr Water Quality Rainfal/=1.00"
Prepared by Horvath Associates, P.A. Page 4
HydroCAD@ 7,10 sin 003899 @ 2005 HydroCAD Software Solutions LLC 8/6/2007

Pond 3P: Bypass CB65 (To HW2ILS2)

Inflow Area =
Inflow =
Outflow =
Primary =
Secondary =

2.010 ac, Inflow Depth> 0.79"
2.72 cfs @ 11.96 hrs, Volume=
2.72 cfs @ 11.96 hrs, Volume=
2.72 cfs @ 11.96 hrs, Volume=
0.00 cfs @ 0.00 hrs, Volume=

for Water Quality event
0.132 af
0,132 af, Atten= 0%, Lag= 0.0 min
0.132 af
0.000 af

Routing by Stor-Ind method, Time Span= 0.00-24,00 hrs, dt= 0.01 hrs
Peak Elev= 301.79' @ 11.96 hrs
Plug-Flow detention time= (not calculated: outflow precedes inflow)
Center-of-Mass deL time= (not calculated: outflow precedes inflow)

Device
#1

Outlet Devices
10.0" x 59.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 299.50' S= 0.0136 'I' Cc= 0.900 n= 0.012 Steel, smooth
24.0" x 32.0'long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 300.00' S= 0.0625 'I' Cc= 0.900
n= 0,013 Concrete pipe, bends & connections

Routing
Primary

Invert
300.30'

#2

Secondary 302.00'

Primary OutFlow Max=2.71 cfs @ 11.96 hrs HW=301.78' (Free Discharge)
"t...-1=Culvert (Inlet Controls 2.71 cfs @ 5.0 fps)

Secondary OutFlow Max=O.OO cfs @ 0.00 hrs HW=300.30' (Free Discharge)
"t...-2=Culvert (Controls 0.00 cfs)

Pond 3P: Bypass CB65 (To HW2JLS2)

Hydrograph

3-

-Inflow
-Outflow
- Primary
- Secondary

Inflow Area=2.010 ac
Peak Elev=301.79'

2
~
~
~
0
u:
1

;
14

'---
---------------.

--

0-,
10

11

12
Time (hours)

13

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S:\Drawings\05\0511\Project Calcs\Greenway (Phase 2)\HydroCAD Bypass Design\
I 0511.2 Bypass Design Type II 24-hr Water Quality Rainfal/=1.00"
Prepared by Horvath Associates, P.A. Page 5
HydroCAD@ 7.10 sIn 003899 @ 2005 HydroCAD Software Solutions LLC 8/6/2007
I Hydrograph for Pond 3P: Bypass CBSS (To HW2/LS2)
I Time Inflow Elevation Outflow Primary Secondary
(hours) (cfs) (feet) (cfs) (cfs) (cfs)
0.00 0.00 300.30 0.00 0.00 0.00
0.50 0.00 300.30 0.00 0.00 0.00
I 1.00 0.00 300.30 0.00 0.00 0.00
1.50 0.00 300.30 0.00 0.00 0.00
2.00 0.00 300.30 0,00 0.00 0.00
2.50 0.00 300.30 0,00 0.00 0.00
I 3.00 0.00 300.30 0.00 0.00 0.00
3.50 0,00 300.30 0.00 0,00 0.00
4,00 0.00 300.31 0.00 0.00 0.00
I 4,50 0.00 300.32 0.00 0.00 0.00
5.00 0.01 300,34 0,01 0.01 0.00
5.50 0.01 300.34 0.01 0.01 0.00
6.00 0.01 300.35 0.01 0.01 0,00
I 6.50 0.01 300.35 0.01 0.01 0.00
7.00 0,02 300.36 0.02 0.02 0.00
7.50 0.02 300.37 0,02 0.02 0.00
8.00 0.02 300.37 0.02 0.02 0.00
I 8.50 0.03 300.38 0.03 0.03 0.00
9.00 0.04 300.39 0.04 0.04 0.00
9.50 0.04 300.40 0,04 0.04 0.00
10.00 0.05 300.41 0.05 0.05 0.00
I 10.50 0.07 300.43 0,07 0.07 0.00
11.00 0.10 300.46 0.10 0.10 0,00
11.50 IIUS 300.52 0.~8 (US 0.00
12.00 2.27 30~ .4$ 2.27 2.27 0.00
I 12.50 0.20 300,53 0.20 0.20 0.00
13.00 0.13 300.48 0.13 0.13 0.00
13.50 0.10 300.46 0.10 0.10 0,00
I 14.00 0.07 300.44 0.07 0,07 0.00
14.50 0.07 300.43 0.07 0,07 0.00
15,00 0,06 300.42 0.06 0.06 0.00
15,50 0.05 300.41 0,05 0.05 0.00
I 16.00 0.05 300.41 0.05 0.05 0.00
16.50 0.04 300.40 0,04 0,04 0.00
17,00 0.04 300.40 0.04 0,04 0.00
17.50 0.04 300.40 0.04 0.04 0.00
I 18.00 0.04 300.39 0,04 0,04 0.00
18.50 0.03 300.39 0.03 0.03 0.00
19.00 0.03 300.39 0.03 0,03 0.00
19.50 0.03 300.38 0.03 0.03 0.00
I 20.00 0.03 300.38 0,03 0.03 0.00
20.50 0.03 300,38 0,03 0.03 0,00
21.00 0.02 300.38 0.02 0.02 0.00
I 21.50 0.02 300.38 0.02 0.02 0.00
22.00 0.02 300.38 0.02 0.02 0.00
22.50 0.02 300.38 0,02 0.02 0.00
23.00 0.02 300.37 0.02 0.02 0.00
I 23.50 0.02 300,37 0.02 0.02 0.00
24.0C C.02 300.37 0.02 0.02 a.oe
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LEVEL SPREADER AERIAL PHOTOS

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C ,')1
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- ----

{J

0511 LS-2

Page 1

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Ramar~:
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Horvath Associates

GPS Survey
5 June 2007

INPUT
State Plane, NAD83
3200 - North Carolina, U,S, Feet

OUTPUT
UTM, NAD83
17 - 84W to 78W, Meters

LS2

1/1

NorthingN: 3985043.548
EastonglX: 695188.599

NorthingN: 815417.89
E@stinglX: 2048891.43

Convergence: 0 05 43.39171
Scale Factor: 0.999955555

Convergence: 1 16 22.14323
Scale Factor: 1.000069466

Grid Shift (m.): XlEasting = 70685.2, Y/Nortl1ing = 3736503.7

Coq:SCOri '/6.0.1, U.S. Army Corps of t.=ngineers

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I PHOTOS OF FILTER STRIPS
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OPERATIONS AND MAINTENANCE
AGREEMENTS

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Permit Number:
(to be prOVide1; DWQ)
Drainage Area Number: f 2.:

Filter Strip, Restored Riparian Buffer and Level Spreader

Operation and Maintenance Agreement

U-~ i)

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:
The entire filter strip
s stem
The flow splitter device
(if applicable)

Potential roblem:
Trash/ debris is present.

How I will remediate the roblem:
Remove the trash/ debris.

The flow splitter device is
clo ed.
The flow splitter device is
damaged.

Unclog the conveyance and dispose
of an sediment off-site.
Make any necessary repairs or
replace if damage is too large for
re air.

Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3

Page I of3

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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
bypassed it. water until it is established. Provide
lime and a one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslope 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.

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Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3

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Pel'lllit NUlIlher:

'.... "I;;;'j;~;'r.;":;;-:i:i~aT;:j5iTQ)

I m:kmm:Jedge and agree by my signature below that I urn responsible for the
pcrfommnce oCthe maintenance procedures listed abo\"c. I agree 10 notify DWQ OrUllY
problems with the system or prior to any changes to [he system or responsible party.

Pr~iCClnll1l1i.':Grc:cnwa\'
I1AIP drainage area 1l1lmher:4,1

Print IInml~: 41Y11"'J~"v J 1.-1. C; 5.. aAI~ fI1Qg(l/~tt2...______",_._,.._._
Titk:--A1.~M12tE/L., I. M~ dlL. '________
Address:_~:3:3.0_t1B:l24fladS-[Ja,.,.UE._D.ue-1:hM!17-JL,,-C.__.,iJ_?:7Q~
Phone:-9..L9t)73Ea .... 48GB'
Signatllrc:~
Dale: /t2.... c:..I".).Z-

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Nole: The kgally rcsponsibll.' pany should not be a homeowners association unlcs~ more than 501i., of
the 11)!S havc hecn sold and n resident oflhe subdivision has be~n nallled the president.

I. Qa.,meta. W. \.A.)'\ \.=:0 1'\ . a Notary Public for [he Slnte of
Qt)4 -\-\r\ CCl(l)\l (\0. . County of _\(.e:f5D-V\ . do hereby ccrti I): that
51. CJV"o...\g mOLci 5Dv\ personally appeared before me this ~
day of _Q<:::.tDl:>~{ . _L.o05[,. and acknowledge the due execution ofthe
forgoing niter strip. riparian hurler, and/or level spreader maintenance requirements.
Witness my hand and oi1icial seal.

PAMELA W. WILSON
NOTARY PUBLIC
Person County
North Carolina 1_
My Commission Expires \ I ~ \ IjJl\

SEAL

My commission expires

\ { "6 \ I to ~ \

Fonn SWU401.Lc\'c1 Spreader. Filter Strip. Restored Riparian BuITerO&fo."-Rc".J

Page 3 01'3

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Permit Number:
(to be provide1.by DWQ) . "\
Drainage Area Number: g,?- {,LS 2- J

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:
The entire filter strip
s stem
The flow splitter device
(if applicable)

Potential roblem:
Trash/ debris is present.

How I will remediate the roblem:
Remove the trash/ debris.

The flow splitter device is
clo ed,
The flow splitter device is
damaged.

Unclog the conveyance and dispose
of an sediment off-site.
Make any necessary repairs or
replace if damage is too large for
re air.

Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3

Page 1 of3

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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
bypassed it. water until it is established. Provide
lime and a one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslope 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.

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Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer O&M-Rev.3

Page 2 of3

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l'el111il Number:

(jO bL' ImJl'hkd :~r DJI'Q)

r m:knowkdgc- and agree: by my signnlllre below thaI I am n:sponsiblt: for the
perlbmlallcc of the maintenance proceuures listed ~lbo\'c. I agree to nOlilY DWQ or any
problems with the system or prior to any changes to the sy~tC'm or responsible party.

P"ldL'C{ l1ame:Greellwav
BMP drabUlgL' area 1II1mber:3.?

Print name:_CLl!!f~ L~
Titlc:--'.11.e~'f3JZLt_j.dM-M,f~'eL
Addrcss:-.:l:3.$p_~.RGIGt17N ~/lfIdJlIC
Phone: c;..I..9.-:....."3_a:~ -;ZJt4:.~
Sigth1ll1re:__~
Date: /p-41~-t.2S..

6 -~:eA/~ nb~J:5o,J

DuR.JM.1fI1 ).le.,. ;;:27t:'-S-
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Note: The legally responsible party shl1ulll not be a hllI1lCO\\'Il~rs as~ociation unless mort: than 50'~'. or
the lots have been sold and a resident of the subdivision has been named the president.

I. 'VO-I{\.,\ .eJo W. vJ \ \ SOY\ . a Notary Public for the State of
NnL-l(v, rr.1Y"O li. f\C,,-. County of Vex ;X)l{'\ , do herehy certify thut
S. C~v-a.~_ 'fv1(jr riSCY\ personally appeared betore me this -Z;I\::-
day of _D_d-ok,l{ . 2.o0'b . and acknowledge the due execution afthe
Ibrgoing !iller Ntrip, riparian hutTer, and/or level spreader maintenance reqllirem~nts.
Wilness my hand and official seal,

c:-
PAMELA W. WILSON
NOTARY PUBUC
Person County
North Carolina
My C~m~~issi?ll ~ \

SEAL

My commission expires

~ L3JJ 7,0\\

Fonn SWU40 I-Level Spreader. Filler Strip, Restored Riparian ButTer O&M-Re\'.3

Page 300