SW4161101_HISTORICAL FILE_20161130

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO. SW
DOC TYPE ❑ CURRENT PERMIT
❑ APPROVED PLANS
�P HISTORICAL FILE
<❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE��(p
YYYYMMDD

DRAINAGE REPORT
CEI Engineering Associates, Inc.
2025 Centre Pointe Blvd., Suite 210
Mendota Heights, MN 55120
Tel. [phone]
The Broadway Group
Foscoe, NC
CEI Project No. 29595.0
November 17, 2016
P� A Ct,Rp<�:'
SEAL =
NC Department of
Environmental Quality
ReceGEC 0 5 2016
Winston-Salem
Regional office
Received
NOV 3 0 2016
-- Land Quality Section1-
Asheville

The Broadway Group — Foscoe, NC
PROJECT DESCRIPTION
The project site is approximately 2.16 acres and is located approximately 260' west of Church
Road (NCSR 1559) on the south side of NC-105 in Foscoe, NC. The proposed project involves
commercial development disturbing 2.13 acres and generating 1.20 acres of impervious surface
consisting of the construction of a 1-story retail building (10,900 SF) and related parking and
drive areas. The project will include subsurface utility construction consisting of a sanitary
service connection, private water well, and storm sewer pipes for routing runoff to a dry
detention basin.
Construction is planned for two phases. The first phase would consist of construction of the dry
detention basin and a temporary berm along the east property line so that all Phase I construction
runoff is diverted to the permanent treatment basin. The proposed building and parking area will
be collected with a series of catch basins and routed to the detention basin located at the south
end of the site. Phase 2 construction involves construction of an east access drive and
supplementary detention basin for runoff from the drive lane. Both basins are proposed to outlet
to the ditch along Church Road to the east, similar to existing conditions.
Existing Condition:
The site is currently undeveloped and consists of native grass cover. It is bound to the north by
highway NC-105, commercial properties to the west and east, and an aggregate -surfaced storage
lot to the south. Currently all runoff sheet drains from west to east to an existing ditch along
Church Road at the east end of the site, ultimately draining to Watauga River.
Soils:
On -site soils consist of Reddies loam (sandy loam) up to 26" depth atop gravelly sands. Subsoils
were characterized as HSG B for design of the proposed detention basin.
Stormwater Management:
Design was based on the standards set forth by Watauga County and North Carolina state
regulations as found in the NC DEQ Stormwater Design Manual. A dry detention basin was
selected for the site BMP and was designed to manage the peak Flow from the 1-, 25-, and 100-
year, 24-hour rainfall events to less than existing conditions. The basin was also designed for
water quality to treat runoff from I" over the entire disturbed site area plus an additional 25% of
storage volume for sediment deposition.
Pre-treatment:
Permanent pre-treatment of the runoff is proposed with 3 foot sumps on each of the inlet
structures. Silt fence and inlet protection will also be implemented to provide temporary erosion
control during construction activities. Erosion control and construction sequencing is
summarized on the erosion control plans.

Runoff Rate Comparison:
The tables below summarize the comparison of peak discharge rates from pre -development to
post -development conditions.
Peak Release Rates(CFS)
Storm Event(24-hr)
Pre-Dev.
Post-Dev.
1-year
1.45
1.26
25-year
6.90
4.24
100-year
10.36
6.41
Detention Basin Summa
Total Disturbed Area
= 92,700 SF or 2.13 acres
Temporary Pool Volume
= I "/12 x 92,700 SF = 7,725 CF
Sediment Storage Volume
= 25% x 7,725 CF = 1,931 CF
Total Water Quality Volume Required
= 7,725 + 1,931 = 9,656 CF
Provided Total Storage Volume (at elev. 3011.50') = 20,009 CF
Basin Top
Emergency Overflow
100-year FI W L
Outlet (10" PVC exiting OCS-I
Basin Bottom
= 3012.50'
= 301 1.50'
= 3010.99'
to the east) = 3008.50'
= 3008.50'

Pre -A
4
NC-105
P re-C
On -site ET
Pre-B
Existing Total
Off -site
Subcat Reach on Link Routing Diagram for Foscoe NC —Broadway Group 11-17-16
Prepared by CEI Engineering Associates Inc, Printed 11/1812016
HydroCAD® 10.00-15 s/n 02540 0 2015 HydroCAD Software Solutions LLC

Foscoe NC —Broadway Group 11-17-16
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 2
Area Listing (selected nodes)
Area CN Description
(sq-ft) (subcatchment-numbers)
88,339 69 50-75% Grass cover, Fair, HSG B (Pre-B, Pre-C)
16,451 98 Unconnected pavement, HSG B (Pre -A, Pre-B, Pre-C)
104,790 74 TOTAL AREA

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 3
Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentPre-A: NC-105 Runoff Area=3,668 sf 100.00% Impervious Runoff Depth=2.67"
Tc=5.0 min CN=98 Runoff=0.36 cfs 816 cf
SubcatchmentPre-B: Off -site Runoff Area=10,718 sf 29.00% Impervious Runoff Depth=0.80"
Flow Length=100' Slope=0.0300'/' Tc=8.0 min UI Adjusted CN=73 Runoff=0.31 cfs 711 cf
SubcatchmentPre-C: On -site Runoff Area=90,404 sf 10.70% Impervious Runoff Depth=0.70"
Flow Length=300' Slope=0.0200'P Tc=22.6 min UI Adjusted CN=71 Runoff=1.32 cfs 5,300 cf
Reach ET: Existing Total
Inflow=1.45 cfs 6,828 cf
Outflow=1.45 cfs 6,828 cf
Total Runoff Area = 104,790 sf Runoff Volume = 6,828 cf Average Runoff Depth = 0.78"
84.30% Pervious = 88,339 sf 15.70% Impervious = 16,451 sf

Foscoe NC_Broadway Group 11-17-16 Type 1/ 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment Pre -A: NC-105
Runoff = 0.36 cfs @ 11.96 hrs, Volume= 816 cf, Depth= 2.67"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf) CN Description
3,668 98 Unconnected pavement HSG B
3,668 98 100.00% Impervious Area
3,668 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Pre -A: NC-105
Hydrograph
0.38;O36-
0.34,
-
o.oe
us
r
0.32'.
.. r.
0.3-
0.28'
r
-
0.24'
J2 0.22-
0.2_
r _.
0 0.18-
_ -
LL
0.16
0.14-
r
0.12'.
0.1-
"
a.08,
r r
0.06d
0.044
Type II 24-hr
1-Year Rainfall=2.90
Runoff Area=3,668 sf
Runoff'Volume=816 cf
Runoff Depth=2.67"
.Tc=5.0 min
CN=98
60 62 64 66 68 70
Time (hours)
❑ Runott

Foscoe NC Broadway Group 11-17-16 Type/if 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment Pre-B: Off -site
Runoff = 0.31 cfs @ 12.01 hrs, Volume= 711 cf, Depth= 0.80"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf)
CN
Add
Description
3,108
98
Unconnected pavement, HSG B
7,610
69
50-75% Grass cover, Fair, HSG B
10,718
77
73
Weighted Average, UI Adjusted
7,610
69
69
71.00% Pervious Area
3,108
98
98
29.00% Impervious Area
3,108
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
8.0 100 0.0300 0.21 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Pre-B: Off -site
Hydrograph
0.327
o.3v
-� Type 1124-h r
cis
0.3'
0.26'.
.1-Year-Rainfall=2.90"
0.26 1_
- - ' - - -Runoff Area=10,718 sf
0.24-
0.22-.
-.
Runoff Volume=711 cf
F
Runoff Depth=0.80"
018
.2 0.16
.'. Flow
0.12-
,Length=100'.
�.. Slope=0.0300 '/'
°.,
Tc=8.0 min
008
UI Adjusted CN=73
0.04-
i
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment Pre-C: On -site
Runoff = 1.32 cfs @ 12.18 hrs, Volume= 5,300 cf, Depth= 0.70"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf)
CN
Adj
Description
9,675
98
Unconnected pavement, HSG B
80,729
69
50-75% Grass cover, Fair HSG B
90,404
72
71
Weighted Average, UI Adjusted
80,729
69
69
89.30% Pervious Area
9,675
98
98
10.70% Impervious Area
9,675
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
22.6 300 0.0200 0.22 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Pre-C: On -site
Hydrograph
ums
Type II 24-hr
1-Year Rainfall=2.90"
Runoff Area=90,404 sf
Runoff Volume='5,300 cf
Runoff Depth=0.70"
.2 Flow Length=300'
Slope=0.0200 '/'
Tc=22.6 min
UI Adjusted CN=71
4 6 8 10 12 14 15 18 20 22 24 26 28 30 32 34 36 38 41
Time (hours)
Runoff

Foscoe NC Broadway Group 11-17-16 Type lI 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 7
Summary for Reach ET: Existing Total
Inflow Area = 104,790 sf, 15.70% Impervious, Inflow Depth = 0.78" for 1-Year event
Inflow = 1.45 cfs @ 12.18 hrs, Volume= 6,828 cf
Outflow = 1.45 cfs @ 12.18 hrs, Volume= 6,828 cf, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Reach ET: Existing Total
Hydrograph
® InFlow
❑ Outtlow
Time (hours(

Foscoe NC_Broadway Group 11-17-16 Type // 24-hr 25-Year Rainfall=6.13'
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 8
Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentPre-A: NC-105 Runoff Area=3,668 sf 100.00% Impervious Runoff Depth=5.89"
Tc=5.0 min CN=98 Runoff=0.76 cfs 1,801 cf
SubcatchmentPre-B: Off -site Runoff Area=10,718 sf 29.00% Impervious Runoff Depth=3.20"
Flow Length=100' Slope=0.0300'/' Tc=8.0 min UI Adjusted CN=73 Runoff=1.30 cfs 2,855 cf
SubcatchmentPre-C: On -site Runoff Area=90,404 sf 10.70% Impervious Runoff Depth=3.00"
Flow Length=300' Slope=0.0200'/' Tc=22.6 min UI Adjusted CN=71 Runoff=6.42 cfs 22,630 cf
Reach ET: Existing Total
Inflow=6.90 cfs 27,286 cf
Outflow=6.90 cfs 27,286 cf
Total Runoff Area = 104,790 sf Runoff Volume = 27,286 cf Average Runoff Depth = 3.12"
84.30% Pervious = 88,339 sf 15.70% Impervious = 16,451 sf

Foscoe NC_Broadway Group 11-17-16 Type // 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment Pre -A: NC-105
Runoff = 0.76 cfs @ 11.96 hrs, Volume= 1,801 cf, Depth= 5.89"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (so CN Description
3,668 98 Unconnected pavement, HSG B
3,668 98 100.00% Impervious Area
3,668 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Pre -A: NC-105
Hydrograph
0.6- 0.7e0s - -- - - - - -'
0.75- - Type II 24-hr
°' 25-Year Rainfall=6.13"
Runoff Area=3,668 sf
0.55-
0.5Runoff Volume=1,801 cf
0.45' " - : _ .Runoff Depth=5.89"
LL
°' Tc=5.0 min
0.3 CN=98
0.25'.
0.2-
0.15-
i2 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)
❑ Runott

Foscoe NC_Broadway Group 11-17-16 Type 1/ 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD010.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 10
Summary for Subcatchment Pre-B: Off -site
Runoff = 1.30 cfs @ 12.00 hrs, Volume= 2,855 cf, Depth= 3.20"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (sf)
CN
Adj
Description
3,108
98
Unconnected pavement, HSG B
7,610
69
50-75% Grass cover, Fair, HSG B
10,718
77
73
Weighted Average, UI Adjusted
7,610
69
69
71.00% Pervious Area
3,108
98
98
29.00% Impervious Area
3,108
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (f /ft) (ft/sec) (cfs)
8.0 100 0.0300 0.21 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Pre-B: Off -site
Hydrograph
❑ Runoti
1 30 ds
Type II 24-hr
25-Year Rainfall=6.13"
Runoff Area=10,718 sf
Runoff Volume='2,855 cf
Runoff Depth=3.20"
Flow Length=100'
Slope=0.0300 '/'
Tc=8.0 min
UI Adjusted CN=73
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type 1124-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment Pre-C: On -site
Runoff = 6.42 cfs @ 12.16 hrs, Volume= 22,630 cf, Depth= 3.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type 11 24-hr 25-Year Rainfall=6.13"
Area (sf)
CN
Ad*
Description
9,675
98
Unconnected pavement, HSG B
80,729
69
50-75% Grass cover, Fair, HSG B
90,404
72
71
Weighted Average, UI Adjusted
80,729
69
69
89.30% Pervious Area
9,675
98
98
10.70% Impervious Area
9,675
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
22.6 300 0.0200 0.22 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Pre-C: On -site
Hydrograph
7 - O Runott
eez cis
Type II 24-hr
6 25-Year Rainfall=613"
6: Runoff Area=90,404 sf
Runoff .Volume=22,630 cf
4- x Runoff Depth=3.,00"
'Flow Length=300'
3 Slope=0.0200 T
2- Tc=22.6 min
UI Adjusted CN=71
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 36 4(
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 12
Summary for Reach ET: Existing Total
Inflow Area = 104,790 sf, 15.70% Impervious, Inflow Depth = 3.12" for 25-Year event
Inflow = 6.90 cfs @ 12.13 hrs, Volume= 27,286 cf
Outflow = 6.90 cfs @ 12.13 hrs, Volume= 27,286 cf, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 his, dt= 0.01 hrs
Reach ET: Existing Total
Hydrograph
® Inflow
—11
❑ Outflow
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours(

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 13
Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentPre-A: NC-105 Runoff Area=3,668 sf 100.00% Impervious Runoff Depth=7.66"
Tc=5.0 min CN=98 Runoff=0.98 cfs 2,341 cf
SubcatchmentPre-B: Off -site Runoff Area=10,718 sf 29.00% Impervious Runoff Depth=4.72"
Flow Length=100' Slope=0.0300'f Tc=8.0 min UI Adjusted CN=73 Runoff=1.91 cfs 4,217 cf
SubcatchmentPre-C: On -site Runoff Area=90,404 sf 10.70% Impervious Runoff Depth=4.49"
Flow Length=300' Slope=0.0200'/' Tc=22.6 min UI Adjusted CN=71 Runoff=9.66 cfs 33,845 cf
Reach ET: Existing Total
Inflow=10.36 cfs 40,403 cf
Outflow=10.36 cfs 40,403 cf
Total Runoff Area = 104,790 sf Runoff Volume = 40,403 cf Average Runoff Depth = 4.63"
84.30% Pervious = 88,339 sf 15.70% Impervious = 16,451 sf

Foscoe NC Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment Pre -A: NC-105
Runoff = 0.98 cfs @ 11.96 hrs, Volume= 2,341 cf, Depth= 7.66"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (so CN Description
3,668 98 Unconnected pavement, HSG B
3,668 98 100.00% Impervious Area
3,668 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Pre -A: NC-105
Hydrograph
Type II 24-hr
100-Year Rainfall=7.96"
Runoff Area=3,668 sf
Runoff Volume=2,341 cf
Runoff,Depth=7.66"
Tc=5.0 min
CN=98
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 4(
Time (hours)
❑ RunoR

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 15
Summary for Subcatchment Pre-B: Off -site
Runoff = 1.91 cfs @ 11.99 hrs, Volume= 4,217 cf, Depth= 4.72"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (sf)
CN
Adi
Description
3,108
98
Unconnected pavement, HSG B
7,610
69
50-75% Grass cover, Fair, HSG B
10,718
77
73
Weighted Average, UI Adjusted
7,610
69
69
71.00% Pervious Area
3,108
98
98
29.00% Impervious Area
3,108
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
8.0 100 0.0300 0.21 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
II
Subcatchment Pre-B: Off -site
Hydrograph
Type II 24-hr
100-Year Rainfall=7.90"
Runoff Area=10,718 sf
Runoff Volume=4,217 cf
Runoff ,Depth =4.72"
Flow'Length=100'
Slope=0.0300 '/'
Tc -8.0 min
UI Adjusted CN=73
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7,90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 16
Summary for Subcatchment Pre-C: On -site
Runoff = 9.66 cfs @ 12.15 hrs, Volume= 33,845 cf, Depth= 4.49"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (so
CN
Adi
Description
9,675
98
Unconnected pavement, HSG B
80,729
69
50-75% Grass cover, Fair, HSG B
90,404
72
71
Weighted Average, UI Adjusted
80,729
69
69
89.30% Pervious Area
9,675
98
98
10.70% Impervious Area
9,675
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (f /ft) (f /sec) (cfs)
22.6 300 0.0200 0.22 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Pre-C: On -site
Hydrograph
❑Runoff
Type II 24-hr
9 100-Year Rainfall=7.90"
6- Runoff Area=90,404 sf
Runoff Volume=33,845 cf
6 Runoff Depth=4.49"
0 5- Flow Length=30,0`
LL
4- _ S160e=0.0200'1r1r
3_ Tc=22.6 min
UI Adjusted CN=71
2-
o
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 62 54 66 66 60 62 64 68 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 17
Summary for Reach ET: Existing Total
Inflow Area = 104,790 sf, 15.70% Impervious, Inflow Depth = 4.63" for 100-Year event
Inflow = 10.36 cfs @ 12.13 hrs, Volume= 40,403 cf
Outflow = 10.36 cfs @ 12.13 hrs, Volume= 40,403 cf, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Reach ET: Existing Total
Hydrograph
® Inflow
❑ OUMOW
Time (hours)

Post-C
9
On -site
Post-B
Ott -site 1 P
Detention Basin
Post -A
NC-105 Post-E
/hutch Rd.
2P UT
Access Roadwe post-F
Basin \ Undetain d Total
Undetained
Post-D
On -site access road
PT
Proposed Total
Subcat Reach on Link

Foscoe NC_Broadway Group 11-17-16
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 2
Area Listing (selected nodes)
Area CN Description
(sq-ft) (subcatchment-numbers)
49,273 69 50-75% Grass cover, Fair, HSG B (Post-B, Post-C, Post-D, Post-F)
55,517 98 Unconnected pavement, HSG B (Post -A, Post-B, Post-C, Post-D, Post-E,
Post-F)
104,790 84 TOTAL AREA

Foscoe NC_Broadway Group 11-17-16 Type // 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 3
Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentPost-A: NC-105 Runoff Area=3,668 sf 100.00% Impervious Runoff Depth=2.67"
Tc=5.0 min CN=98 Runoff=0.36 cfs 816 cf
SubcatchmentPost-B: Off -site Runoff Area=10,718 sf 29.00% Impervious Runoff Depth=0.80"
Flow Length=100' Slope=0.0300 T Tc=8.0 min UI Adjusted CN=73 Runoff=0.31 cfs 711 cf
SubcatchmentPost-C: On -site Runoff Area=63,548 sf 63.21% Impervious Runoff Depth=1.65"
Flow Length=90' Slope=0.01007 Tc=11.4 min CN=87 Runoff=3.52 cfs 8,749 cf
SubcatchmentPost-D: On -site access road Runoff Area=21,352 sf 36.40% Impervious Runoff Depth=1.18"
Tc=5.0 min CN=80 Runoff=1.07 cfs 2,092 cf
SubcatchmentPost-E: Church Rd. Runoff Area=650 sf 100.00% Impervious Runoff Depth=2.67"
Tc=5.0 min CN=98 Runoff=0.06 cfs 145 cf
SubcatchmentPost-F: Undetained Runoff Area=4,854 sf 3.09% Impervious Runoff Depth=0.62"
Tc=5.0 min UI Adjusted CN=69 Runoff=0.12 cfs 250 cf
Reach PT: Proposed Total Inflow=1.26 cfs 12,760 cf
Outflow=1.26 cfs 12,760 cf
Pond 1P: Detention Basin Peak EIev=3,009.32' Storage=4,464 cf Inflow=3.82 cfs 9,460 cf
Primary=0.43 cfs 9,459 cf Secondary=0.00 cfs 0 cf Outflow=0.43 cfs 9,459 cf
Pond 2P: Access Road Swale Basin Peak EIev=3,008.09' Storage=486 cf Inflow=1.07 cfs 2,092 cf
Primary=0.55 cfs 2,092 cf Secondary=0.00 cfs 0 cf Outflow=0.55 cfs 2,092 cf
Link UT: Undetained Total
Inflow=0.53 cfs 1,210 cf
Primary=0.53 cfs 1,210 cf
Total Runoff Area = 104,790 sf Runoff Volume = 12,762 cf Average Runoff Depth = 1.46"
47.02% Pervious = 49,273 sf 52.98% Impervious = 55,517 sf

Foscoe NC_Broadway Group 11-17-16 Type/1 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment Post -A: NC-105
Runoff = 0.36 cfs @ 11.96 hrs, Volume= 816 cf, Depth= 2.67"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (so CN Description
3,668 98 Unconnected pavement, HSG 6
3,668 98 100.00% Impervious Area
3,668 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Post -A: NC-105
Hydrograph
0 RunOR
0.36'
.
a.3e
as
Type II 24-fir
0.34-
,
°03
1=Year Rainfall=2.90"
0.281
_ -
Runoff.Area=3,668 sf
0.26-.-'----
024
Runoff,V61ume=816 cf
E 0.22
Runoff Depth=2.67"
0.16'
:: :Tc=5.0 min
0.147
-
CN=98
0.12'
------
- --- , -.---
0.1-
0.08;
0.0s0.04
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 41
Time (hours(

Foscoe NC_Broadway Group 11-17-16 Type 1/ 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment Post-B: Off -site
Runoff = 0.31 cfs @ 12.01 hrs, Volume= 711 cf, Depth= 0.80"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf)
CN
Adl
Description
3,108
98
Unconnected pavement, HSG B
7,610
69
50-75% Grass cover, Fair, HSG B
10,718
77
73
Weighted Average, UI Adjusted
7,610
69
69
71.00% Pervious Area
3,108
98
98
29.00% Impervious Area
3,108
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
8.0 100 0.0300 0.21 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Post-B: Off -site
Hydrograph
O32-
Oi31 c(s
Type II 24-hr
0.3-
0.28.
- ;1-Year Rainfall=2.90"
0.2
_ - -
,- - - - - - - - Runoff Area=10,718 sf -
4-
022-
-- Runoff V61ume=711 -cf
02
Runoff Depth=0.80"
u
- '
0.18
0.16-
LL
Flow Length=100'
0.14-
Slope=0.0300 '/'
012;
Tc=8.0 min
008
UI Adjusted CN=73
0.06-
- -
4 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type Il 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment Post-C: On -site
Runoff = 3.52 cfs @ 12.03 hrs, Volume= 8,749 cf, Depth= 1.65"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf) CN Description
40,169
98
Unconnected pavement, HSG B
23,379
69
50-75% Grass cover, Fair, HSG B
63,548
87
Weighted Average
23,379
69
36.79% Pervious Area
40,169
98
63.21 % Impervious Area
40,169
100.00% Unconnected
Tic Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
11.4 90 0.0100 0.13 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
50 n
3-
u 2-
0
LL
o-
0 2 4 6 8 10 12
Subcatchment Post-C: On -site
Hydrograph
-Type II 24-hr
1-Year Rainfall=2.90"
Runoff Area=63,548 sf
Runoff Volume=8,749 cf
RunoffDepth=1.65"
Flow Length=90'
Slope=0.0100 '/'
;Tc=11.4 min
CN=87
8 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)
O Runoff

Foscoe NC_Broadway Group 11-17-16 Type 1/ 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment Post-D: On -site access road
Runoff = 1.07 cfs @ 11.96 hrs, Volume= 2,092 cf, Depth= 1.18"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf) CN Description
7,772
98
Unconnected pavement, HSG B
13,580
69
50-75% Grass cover, Fair, HSG B
21,352
80
Weighted Average
13,580
69
63.60% Pervious Area
7,772
98
36.40% Impervious Area
7,772
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment Post-D: On -site access road
Hydrograph
❑ Runofl
1.D ds
a
Type II 24-hr
1-Year Rainfall=2.90"
Runoff Area=21,352 sf
Runoff Volume=2,092 cf
Runoff Depth=1.18"
Tc=5.0 min
CN=80
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type II 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment Post-E: Church Rd.
Runoff = 0.06 cfs @ 11.96 hrs, Volume= 145 cf, Depth= 2.67"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (so CN Description
650 98 Unconnected pavement HSG B
650 98 100.00% Impervious Area
650 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (f /sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Post-E: Church Rd.
Hydrograph
0.07-
°.°65-
0.06
Type II':24-fir
tls
0.66-
0.055-
_� �
1-Year Rainfall=2.90"
005
:.
Runoff Area=650 sf
0.045
Runoff;Voltirne=145 cf
°04
0.035-
Runoff Depth=2.6Tr
0
v_ 0.03-
Tc=5.0 min
0.025-
CN=98
0.02-
_
0.015-
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type // 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment Post-F: Undetained
Runoff = 0.12 cfs @ 11.97 hrs, Volume= 250 cf, Depth= 0.62"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 1-Year Rainfall=2.90"
Area (sf)
CN
Adj
Description
150
98
Unconnected pavement, HSG B
4,704
69
50-75% Grass cover, Fair, HSG B
4,854
70
69
Weighted Average, UI Adjusted
4,704
69
69
96.91 % Pervious Area
150
98
98
3.09% Impervious Area
150
100.00% Unconnected
Tc Length
Slope
Velocity Capacity Description
(min) (feet)
(ft/ff)
(ft/sec) (cfs)
5.0
Direct Entry, Tc Min
Subcatchment Post-F: Undetained
Hydrograph
0.13-
O Runal/
012
Type II 24-hr
0.11-
.
1-Ydar Rainfall=2.90r'
01_
0.09
- Runoff Area=4,854sf
0.08-
Ru'noff,V61ume=250_cf
007
Runoff :Depth=0.62'r
LL 0.06-
7c=5.0 min
0.05-
004-
-� - - - - UI Adjusted CN=69
0.03-
ON
- - - - -
12 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1/ 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydrOCAD010.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 10
Summary for Reach PT: Proposed Total
.Inflow Area = 104,790 sf, 52.98% Impervious, Inflow Depth = 1.46" for 1-Year event
Inflow = 1.26 cfs @ 11.99 hrs, Volume= 12,760 cf
Outflow = 1.26 cfs @ 11.99 hrs, Volume= 12,760 cf, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Reach PT: Proposed Total
Hydrograph
13 Inflow
CI OuMow
Time (hours(

Foscoe NC_Broadway Group 11-17-16 Type // 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 © 2015 HydroCAD Software Solutions LLC Page 11
Summary for Pond 1P: Detention Basin
Inflow Area = 74,266 sf, 58.27% Impervious, Inflow Depth = 1.53" for 1-Year event
Inflow = 3.82 cfs @ 12.03 hrs, Volume= 9,460 cf
Outflow = 0.43 cfs @ 12.55 hrs, Volume= 9,459 cf, Atten= 89%, Lag= 31.3 min
Primary = 0.43 cfs @ 12.55 hrs, Volume= 9,459 cf
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Peak Elev= 3,009.32' @ 12.55 hrs Surf.Area= 5,899 sf Storage= 4,464 cf
Plug -Flow detention time=177.0 min calculated for 9,459 cf (100% of inflow)
Center -of -Mass det. time= 176.9 min ( 1,005.4 - 828.4 )
Volume Invert Avail.Storage Storage Description
#1 3,008.50' 29,024 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
3,008.50 5,016 0 0
3,009.00 5,551 2,642 2,642
3,010.00 6,644 6,098 8,739
3,011.00 7,798 7,221 15,960
3,011.50 8,398 4,049 20,009
3,012.00 9,011 4,352 24,362
3,012.50 9,640 4,663 29,024
Device Routing Invert Outlet Devices
#1 Secondary 3,011.50' 10.0' long x 4.0' breadth EO Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66
2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32
#2 Primary 3,008.50' 10.0" Vert. Orifice/Grate C= 0.600
#3 Device 2 3,011.00' 4.0' long x 0.5' breadth Throat Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4 Device 2 3,009.50' 10.0" W x 10.0" H Vert. Orifice/Grate C= 0.600
#5 Device 2 3,008.50' 4.0" W x 4.0" H Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=0.43 cfs @ 12.55 hrs HW=3,009.32' (Free Discharge)
L =Orifice/Grate (Passes 0.43 cfs of 1.67 cfs potential flow)
3=Throat Weir ( Controls 0.00 cfs)
=Orifice/Grate ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 0.43 cfs @ 3.88 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=3,008.50' (Free Discharge)
1=EO Weir ( Controls 0.00 cfs)

6
Foscoe NC_Broadway Group 11-17-16 Type/1 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 12
Pond 1P: Detention Basin
Hydrograph
❑ Inflow
3.8as ❑ Outflow
4-
3-
0 2"
M
Inflow Area=74,266 sf o sew dary
Peak, Elev=3,009.32'
Storage=4,464 cf
6 8 101214 16 18202224262830323436384042444648505254565860626466687072
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type/1 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 13
Summary for Pond 2P: Access Road Swale Basin
Inflow Area = 21,352 sf, 36.40% Impervious, Inflow Depth = 1.18" for 1-Year event
Inflow = 1.07 cfs @ 11.96 hrs, Volume= 2,092 cf
Outflow = 0.55 cfs @ 12.04 hrs, Volume= 2,092 cf, Atten= 49%, Lag= 4.8 min
Primary = 0.55 cfs @ 12.04 hrs, Volume= 2,092 cf
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs / 2
Peak Elev= 3,008.09' @ 12.04 hrs Surf.Area= 1,067 sf Storage= 486 cf
Plug -Flow detention time= 27.7 min calculated for 2,091 cf (100% of inflow)
Center -of -Mass det. time= 27.8 min ( 871.5 - 843.7 )
Volume Invert Avail.Storage Storage Description
#1 3,007.50' 5,395 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
3,007.50 600 0 0
3,008.00 980 395 395
3,009.00 1,960 1,470 1,865
3,010.00 5,100 3,530 5,395
Device Routing Invert Outlet Devices
#1 Secondary 3,009.20' 5.0' long x 4.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66
2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32
#2 Primary 3,007.50' 6.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=0.55 cfs @ 12.04 hrs HW=3,008.09' (Free Discharge)
t2=Orifice/Grate (Orifice Controls 0.55 cfs @ 2.80 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=3,007.50' (Free Discharge)
1=Broad-Crested Rectangular Weir( Controls 0.00 cfs)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 14
Pond 2P: Access Road Swale Basin
Hydrograph
tIDch
19
D
0
'V
0.5,
10
m Inflow
❑ Outflow
Inflow Area=21,352 sf
o se o dary
Peak Elev=3,008.09'
Storage=486 cf
101214 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 6062 64 66
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type // 24-hr 1-Year Rainfall=2.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD010.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 15
Summary for Link UT: Undetained Total
Inflow Area = 9,172 sf, 48.71 % Impervious, Inflow Depth = 1.58" for 1-Year event
Inflow = 0.53 cfs @ 11.96 hrs, Volume= 1,210 cf
Primary = 0.53 cfs @ 11.96 hrs, Volume= 1,210 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Link UT: Undetained Total
Hydrograph
9 Inflow
❑ Primary
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type/1 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 sln 02540 ©2015 HydroCAD Software Solutions LLC Page 16
Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentPost-A: NC-105 Runoff Area=3,668 sf 100.00% Impervious Runoff Depth=5.89"
Tc=5.0 min CN=98 Runoff=0.76 cfs 1,801 cf
SubcatchmentPost-B: Off -site Runoff Area=10,718 sf 29.00% Impervious Runoff Depth=3.20"
Flow Length=100' Slope=0.0300'/' Tc=8.0 min UI Adjusted CN=73 Runoff=1.30 cfs 2,855 cf
SubcatchmentPost-C: On -site Runoff Area=63,548 sf 63.21% Impervious Runoff Depth=4.64"
Flow Length=90' Slope=0.01 007 Tc=11.4 min CN=87 Runoff=9.49 cfs 24,581 cf
SubcatchmentPost-D: On -site access road Runoff Area=21,352 sf 36.40% Impervious Runoff Depth=3.90"
Tc=5.0 min CN=80 Runoff=3.45 cfs 6,937 cf
SubcatchmentPost-E: Church Rd. Runoff Area=650 sf 100.00% Impervious Runoff Depth=5.89"
Tc=5.0 min CN=98 Runoff=0.13 cfs 319 cf
SubcatchmentPost-F: Undetained Runoff Area=4,854 sf 3.09% Impervious Runoff Depth=2.61"
Tc=5.0 min UI Adjusted CN=69 Runoff=0.58 cfs 1,138 cf
Reach PT: Proposed Total Inflow=4.24 cfs 37,630 cf
Outflow=4.24 cfs 37,630 cf
Pond 1P: Detention Basin Peak EIev=3,010.43' Storage=11,688 cf Inflow=10.73 cfs 27,436 cf
Primary=3.02 cfs 27,434 cf Secondary=0.00 cfs 0 cf Outflow=3.02 cfs 27,434 cf
Pond 2P: Access Road Swale Basin Peak EIev=3,009.06' Storage=1,982 cf Inflow=3.45 cfs 6,937 cf
Primary=1.08 cfs 6,937 cf Secondary=0.00 cfs 0 cf Outflow=1.08 cfs 6,937 cf
Link UT: Undetained Total
Inflow=1.48 cfs 3,258 cf
Primary=1.48 cfs 3,258 cf
Total Runoff Area = 104,790 sf Runoff Volume = 37,632 cf Average Runoff Depth = 4.31"
47.02% Pervious = 49,273 sf 52.98% Impervious = 55,517 sf

Foscoe NC_Broadway Group 11-17-16 Type 1l 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 17
Summary for Subcatchment Post -A: NC-105
Runoff = 0.76 cfs @ 11.96 hrs, Volume= 1,801 cf, Depth= 5.89"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (so CN Description
3,668 98 Unconnected pavement, HSG B
3,668 98 100.00% Impervious Area
3,668 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Post -A: NC-105
0.5-
0 04_
.2
0.35-
0.3'
. .
0.25-
0.2-
0.15-
0.1-
Type II 24-hr
25-Year Rainfall=6.13"
Runoff Area=3,668 sf
Runoff,Volume=1,801 cf
Runoff Depth=5.89"
Tc=5.0 min
CN=98
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (houn)

Foscoe NC_Broadway Group 11-17-16 Type Il 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 18
Summary for Subcatchment Post-B: Off -site
Runoff = 1.30 cfs @ 12.00 hrs, Volume= 2,855 cf, Depth= 3.20"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (so
CN
Add
Description
3,108
98
Unconnected pavement, HSG B
7,610
69
50-75% Grass cover, Fair, HSG B
10,718
77
73
Weighted Average, UI Adjusted
7,610
69
69
71.00% Pervious Area
3,108
98
98
29.00% Impervious Area
3,108
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
8.0 100 0.0300 0.21 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Post-B: Off -site
Hydrograph
1.3o M
Type II 24-hr
25-Year Rainfall=6.13"
Runoff Area=10,718 sf
Runoff Volume=2,855 cf
Runoff Depth=3.20"
Flow;Length=100'
Slope=0.0300 /'
Tc=8.0 min
UI Adjusted CN=73
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 4(
Time (hours)
O Runott

Foscoe NC_Broadway Group 11-17-16 Type /I24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 19
Summary for Subcatchment Post-C: On -site
Runoff = 9.49 cfs @ 12.03 hrs, Volume= 24,581 cf, Depth= 4.64"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (sf) CN Description
40,169
98
Unconnected pavement, HSG B
23,379
69
50-75% Grass cover, Fair, HSG B
63,548
87
Weighted Average
23,379
69
36.79% Pervious Area
40,169
98
63.21 % Impervious Area
40,169
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
11.4 90 0.0100 0.13 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Post-C: On -site
10- 94s cis
Type II 24-hr
25-Year Rainfa11=6.13"
.,Runoff Area=63,548 sf
7- 1Runoff'Volume=24,581 cf 6-Runoff Depth=4.64"
0 5 Flow Length=9,0'
LL
4- - ,- - ;-Slope=0.01010.1/'
3: Tc=11.4 min
:.. CN=87
2
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type 11 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 20
Summary for Subcatchment Post-D: On -site access road
Runoff = 3.45 cfs @ 11.96 hrs, Volume= 6,937 cf, Depth= 3.90"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (sfl CN Description
7,772
98
Unconnected pavement, HSG B
13,580
69
50-75% Grass cover, Fair, HSG B
21,352
80
Weighted Average
13,580
69
63.60% Pervious Area
7,772
98
36.40% Impervious Area
7.772
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment Post-D: On -site access road
Hydrograph
34 do
Type II 24-hr
3_ 25-Year Rainfall-6.13rr
Runoff Area=2,1,352 sf
Runoff Volume=6,937 cf
2 Runoff Depth=3.90rr
Tc=5.0 min
CN-80
0 2 4 6 8 10 12 14 16 18 20 22 24 26 26 30 32 34 36 38 41
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type 11 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 21
Summary for Subcatchment Post-E: Church Rd.
Runoff = 0.13 cfs @ 11.96 hrs, Volume= 319 cf, Depth= 5.89"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (sf) CN Description
650 98 Unconnected pavement HSG B
650 98 100.00% Impervious Area
650 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Post-E: Church Rd.
Hydrograph
0.15-.-i.
0.14-
o.,acn
_ e ... Type 11 24-hr
0.13-
012
25-Year Rainfall=6.13"
0.,1.
Runoff Area=650 sf
OM-
Runoff_Volume=319 cf
r
008
Runoff Depth=5.89"
0 0 m-
LL 0.06-
Tc=5.0 min
0.05-
CN=98
0.04-
0.03
0.02
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 41
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type // 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 22
Summary for Subcatchment Post-F: Undetained
Runoff = 0.58 cfs @ 11.96 hrs, Volume= 1,138 cf, Depth= 2.81"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 25-Year Rainfall=6.13"
Area (sf)
CN
Adi
Description
150
98
Unconnected pavement, HSG B
4,704
69
50-75% Grass cover, Fair, HSG B
4,854
70
69
Weighted Average, UI Adjusted
4,704
69
69
96.91 % Pervious Area
150
98
98
3.09% Impervious Area
150
100.00% Unconnected
Tc Length
Slope
Velocity Capacity Description
(min) (feet)
(f /ft)
(f
/sec) (cfs)
5.0
Direct Entry, Tc Min
Subcatchment Post-F: Undetained
Hydrograph
0 RunoH
0.6-
0.55-
0.5,
0.45-
�u
0.35-
0 0.3-
LL
_
0.25-
0.2-
0.15-
0.1-
'
Type II 24-hr
25-Year Rainfall=6.13"
' Runoff Area=4,854 sf
Runoff Volume=1,138 cf
Runoff Depth=2.81"
Tc=5.0 min
UI Adjusted CN=69
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours(

Foscoe NC Broadway Group 11-17-16 Type/1 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 23
Summary for Reach PT: Proposed Total
Inflow Area = 104,790 sf, 52.98% Impervious, Inflow Depth = 4.31" for 25-Year event
Inflow = 4.24 cfs @ 12.20 hrs, Volume= 37,630 cf
Outflow = 4.24 cfs @ 12.20 hrs, Volume= 37,630 cf, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
3-
Reach PT: Proposed Total
10 Olnflow
Outtlow
Inflow Area=104,790 sf
48 50 52 54 56 58 60 62 64 66 68 70 72

Foscoe NC_Broadway Group 11-17-16 Type 1/ 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 24
Summary for Pond 1P: Detention Basin
Inflow Area = 74,266 sf, 58.27% Impervious, Inflow Depth = 4.43" for 25-Year event
Inflow = 10.73 cfs @ 12.02 hrs, Volume= 27,436 cf
Outflow = 3.02 cfs @ 12.23 hrs, Volume= 27,434 cf, Atten= 72%, Lag= 12.4 min
Primary = 3.02 cfs @ 12.23 hrs, Volume= 27,434 cf
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Peak Elev= 3,010.43' @ 12.23 hrs Surf.Area= 7,138 sf Storage= 11,688 cf
Plug -Flow detention time=134.6 min calculated for 27,430 cf (100% of inflow)
Center -of -Mass det. time= 134.9 min ( 934.0 - 799.2 )
Volume Invert Avail.Storage Storage Description
#1 3,008.50' 29,024 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
3,008.50 5,016 0 0
3,009.00 5,551 2,642 2,642
3,010.00 6,644 6,098 8,739
3,011.00 7,798 7,221 15,960
3,011.50 8,398 4,049 20,009
3,012.00 9,011 4,352 24,362
3,012.50 9,640 4,663 29,024
Device Routing Invert Outlet Devices
#1 Secondary 3,011.50' 10.0' long x 4.0' breadth EO Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66
2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32
#2 Primary 3,008.50' 10.0" Vert. Orifice/Grate C= 0.600
#3 Device 2 3,011.00' 4.0' long x 0.5' breadth Throat Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4 Device 2 3,009.50' 10.0" W x 10.0" H Vert. Orifice/Grate C= 0.600
#5 Device 2 3,008.50' 4.0" W x 4.0" H Vert. Orifice/Grate C= 0.600
Primary OutFlow, Max=3.02 cfs @ 12.23 hrs HW=3,010.43' (Free Discharge)
t =Orifice/Grate (Passes 3.02 cfs of 3.23 cfs potential flow)
3=Throat Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 2.31 cfs @ 3.33 fps)
=Orifice/Grate (Orifice Controls 0.71 cfs @ 6.39 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=3,008.50' (Free Discharge)
t1=EO Weir ( Controls 0.00 cfs)

Foscoe NCrr
_Broadway Group 11-17-16 Type I/ 24-hr 25-Year
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 © 2015 HydroCAD Software Solutions LLC Page 25
Pond 1P: Detention Basin
Hydrograph
® Inflow
m.n d _ .. _ _ _ - ❑ Outtlow
❑ Primary
2. Inflow Area=74,266 sf CISecondary
Peak Elev=3,010.43'
10
Storage=11,688 cf
.0 7-
...
3 .. ..
V• 5_
J02 cis i
3-'
32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1l 24-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 26
Summary for Pond 2P: Access Road Swale Basin
Inflow Area = 21,352 sf, 36.40% Impervious, Inflow Depth = 3.90" for 25-Year event
Inflow = 3.45 cfs @ 11.96 hrs, Volume= 6,937 cf
Outflow = 1.08 cfs @ 12.07 hrs, Volume= 6,937 cf, Atten= 69%, Lag= 6.7 min
Primary = 1.08 cfs @ 12.07 hrs, Volume= 6,937 cf
Secondary= 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs / 2
Peak Elev= 3,009.06' @ 12.07 hrs Surf.Area= 2,139 sf Storage= 1,982 cf
Plug -Flow detention time= 24.2 min calculated for 6,936 cf (100% of inflow)
Center -of -Mass det. time= 24.2 min ( 833.5 - 809.3 )
Volume Invert Avail.Storage Storage Description
#1 3,007.50' 5,395 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
3,007.50 600 0 0
3,008.00 980 395 395
3,009.00 1,960 1,470 1,865
3,010.00 5,100 3,530 5,395
Device Routing Invert Outlet Devices
#1 Secondary 3,009.20' 5.0' long x 4.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66
2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32
#2 Primary 3,007.50' 6.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=1.08 cfs @ 12.07 hrs HW=3,009.06' (Free Discharge)
t2=Orifice/Grate (Orifice Controls 1.08 cfs @ 5.50 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=3,007.50' (Free Discharge)
1=Broad-Crested Rectangular Weir( Controls 0.00 cfs)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 27
Pond 2P: Access Road Swale Basin
Hydrograph
I
(. t
O Inflow
❑ Outflow
0 Primary
Inflow Area=21,352 sf ❑ Secondary
Peak Elev=3,009.06'
Storage=1,982 cf
32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 fit 64 66 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 25-Year Rainfall=6.13"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 28
Summary for Link UT: Undetained Total
Inflow Area = 9,172 sf, 48.71 % Impervious, Inflow Depth = 4.26" for 25-Year event
Inflow = 1.48 cfs @ 11.96 hrs, Volume= 3,258 cf
Primary = 1.48 cfs @ 11.96 hrs, Volume= 3,258 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Link UT: Undetained Total
Hydrograph
ueds 1 0 Primary
°"' Inflow Area=9,172 sf
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 29
Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentPost-A: NC-105 Runoff Area=3,668 sf 100.00% Impervious Runoff Depth=7.66"
Tc=5.0 min CN=98 Runoff=0.98 cfs 2,341 cf
SubcatchmentPost-B: Off -site Runoff Area=10,718 sf 29.00% Impervious Runoff Depth=4.72"
Flow Length=100' Slope=0.0300 7' Tc=8.0 min UI Adjusted CN=73 Runoff=1.91 cfs 4,217 cf
SubcatchmentPost-C: On -site Runoff Area=63,548 sf 63.21% Impervious Runoff Depth=6.35"
Flow Length=90' Slope=0.0100 7' Tc=11.4 min CN=87 Runoff=12.77 cfs 33,640 cf
SubcatchmentPost-D: On -site access road Runoff Area=21,352 sf 36.40% Impervious Runoff Depth=5.53"
Tc=5.0 min CN=80 Runoff=4.80 cfs 9,842 cf
SubcatchmentPost-E: Church Rd. Runoff Area=650 sf 100.00% Impervious Runoff Depth=7.66"
Tc=5.0 min CN=98 Runoff=0.17 cfs 415 cf
SubcatchmentPost-IF: Undetained Runoff Area=4,854 sf 3.09% Impervious Runoff Depth=4.26"
Tc=5.0 min UI Adjusted CN=69 Runoff=0.88 cfs 1,725 cf
Reach PT: Proposed Total Inflow=6.41 cfs 52,179 cf
Outflow=6.41 cfs 52,179 cf
Pond 1P: Detention Basin Peak EIev=3,010.99' Storage=15,859 cf Inflow=14.57 cfs 37,857 cf
Primary=3.78 cfs 37,855 cf Secondary=0.00 cfs 0 cf Outflow=3.78 cfs 37,855 cf
Pond 2P: Access Road Swale Basin Peak EIev=3,009.38' Storage=2,823 cf Inflow=4.80 cfs 9,842 cf
Primary=1.21 cfs 9,415 cf Secondary=0.88 cfs 428 cf Outflow=2.08 cfs 9,842 cf
Link UT: Undetained Total
Inflow=2.03 cfs 4,482 cf
Primary=2.03 cfs 4,482 cf
Total Runoff Area = 104,790 sf Runoff Volume = 52,181 cf Average Runoff Depth = 5.98"
47.02% Pervious = 49,273 sf 52.98% Impervious = 55,517 sf

Foscoe NC Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 30
Summary for Subcatchment Post -A: NC-105
Runoff = 0.98 cfs @ 11.96 hrs, Volume= 2,341 cf, Depth= 7.66"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (sf) CN Description
3,668 98 Unconnected pavement, HSG B
3,668 98 100.00% Impervious Area
3,668 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Post -A: NC-105
Hydrograph
❑ RunOR
Type II 24-hr
100-Year Rainfall=7.90"
Runoff Area=3,668 sf
Runoff Volume-2,341 cf
Runoff Depth=7.66"
Tc=5.0 min
CN=98
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type // 24-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 31
Summary for Subcatchment Post-B: Off -site
Runoff = 1.91 cfs @ 11.99 hrs, Volume= 4,217 cf, Depth= 4.72"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (sf)
CN
Adj
Description
3,108
98
Unconnected pavement, HSG B
7,610
69
50-75% Grass cover, Fair HSG B
10,718
77
73
Weighted Average, UI Adjusted
7,610
69
69
71.00% Pervious Area
3,108
98
98
29.00% Impervious Area
3,108
100.00% Unconnected
Tc Length Slope
iin) (feet) (ft/ft)
8.0 100 0.0300
Description
0.21 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Post-B: Off -site
Hydrograph
;Type II 24-hr
100-Year Rainfall=7.90"
Runoff Area=10,718 sf
Runoff,Volume=4,217 cf
Runoff,Depth=4.72"
Flow. Length=100'
Slope=0.0300 '1'
Tc=8.0 min
UI Adjusted CN=73
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 32
Summary for Subcatchment Post-C: On -site
Runoff = 12.77 cfs @ 12.02 hrs, Volume= 33,640 cf, Depth= 6.35"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (sf) CN Description
40,169
98
Unconnected pavement, HSG B
23,379
69
50-75% Grass cover, Fair, HSG B
63,548
87
Weighted Average
23,379
69
36.79% Pervious Area
40,169
98
63.21 % Impervious Area
40,169
100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (f /ft) (ft/sec) (cfs)
11.4 90 0.0100 0.13 Sheet Flow, Grass sheet flow
Grass: Short n= 0.150 P2= 3.49"
Subcatchment Post-C: On -site
14-
13- 12nch
12- - -. Type II 24-hr
11_ 100-Year Rainfall=7.90"
0- Runoff Area=63,548 sf
9. Run off •Volume=33,640 cf
F Runoff Depth=6:35"
u
Flow: Length=90'
LL 6-
5_ • : S16pe=0.0100 '/'
4_ - Tc=11.4 min
3- CND=87
2- 1 -
-� , r--
4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)
❑ RunoR

Foscoe NC Broadway Group 11-17-16 Type/1 24-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD010.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 33
Summary for Subcatchment Post-D: On -site access road
Runoff = 4.80 cfs @ 11.96 hrs, Volume= 9,842 cf, Depth= 5.53"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (sf)
CN
Description
7,772
98
Unconnected pavement, HSG B
13,580
69
50-75% Grass cover, Fair, HSG B
21,352
80
Weighted Average
13,580
69
63.60% Pervious Area
7,772
98
36.40% Impervious Area
7,772
100.00% Unconnected
Tc Length
Slope Velocity Capacity Description
(min) (feet)
(ft/ft)
(f /sec) (cfs)
5.0
Direct Entry,
f4
Subcatchment Post-D: On -site access road
Hydrograph
Type II 24-hr
100-Year Rainfall=7.90"
Runoff Area=21,352 sf
Rtinoff.Volume=9,842 cf
Runoff Depth=5.53"
Tc=5.0 min
CN=80
�2 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)
O Runoff

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 34
Summary for Subcatchment Post-E: Church Rd.
Runoff = 0.17 cfs @ 11.96 hrs, Volume= 415 cf, Depth= 7.66"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (so CN Description
650 98 Unconnected pavement, HSG B
650 98 100.00% Impervious Area
650 100.00% Unconnected
Tc Length Slope Velocity Capacity Description
(min) (feet) (f /ft) (ft/sec) (cfs)
5.0 Direct Entry, Tc Min
Subcatchment Post-E: Church Rd.
r
0-19- -
0.18-. U,
0.17-
0.157
0.14-
0.13'
0.12
0.11-
0.1
LL0 0.09-
0.07.
0.06-.
0.05
0.04
0.03-
0.02:
Type II 24-hr-
100-Year Rainfall=7.90"
Runoff Area=650 sf
Runoff Volume=415 cf
Runoff Depth=7.66"
Tc=5.0 min
CN=98
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
0 Runofl

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD010.00-15 s/n 02540 @ 2015 Hydro CAD Software Solutions LLC Page 35
Summary for Subcatchment Post-F: Undetained
Runoff = 0.88 cfs @ 11.96 hrs, Volume= 1,725 cf, Depth= 4.26"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Type II 24-hr 100-Year Rainfall=7.90"
Area (sf)
CN
Adj
Description
150
98
Unconnected pavement, HSG B
4,704
69
50-75% Grass cover, Fair HSG B
4,854
70
69
Weighted Average, UI Adjusted
4,704
69
69
96.91 % Pervious Area
150
98
98
3.09% Impervious Area
150
100.00% Unconnected
Tc Length
Slope
Velocity Capacity Description
(min) (feet)
(f /ft)
(f
/sec) (cfs)
5.0
Direct Entry, Tc Min
Subcatchment Post-F: Undetained
Hydrograph
Type 11 24-hr
100-Year Rainfall=7.90"
0.65,
ass-
0.5. -
LL i
0.4
0.35-
0.3-
0.25
0.2+
0.15
Runoff Area=4,854 sf
Runoff Volume=1,725 cf
Runoff Depth=4.26"
Tc=5.0 min
U1 Adjusted CN=69
28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD010.00-15 s/n 02540 © 2015 HydroCAD Software Solutions LLC Page 36
Summary for Reach PT: Proposed Total
Inflow Area = 104,790 sf, 52.98% Impervious, Inflow Depth = 5.98" for 100-Year event
Inflow = 6.41 cfs @ 12.04 hrs, Volume= 52,179 cf
Outflow = 6.41 cfs @ 12.04 hrs, Volume= 52,179 cf, Atten= 0%, Lag= 0.0 min
Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Reach PT: Proposed Total
Hydrograph
® Inflow
❑ Outtlow
Time (hours(

Foscoe NC_Broadway Group 11-17-16 Type 1l 24-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD0 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 37
Summary for Pond 1P: Detention Basin
Inflow Area = 74,266 sf, 58.27% Impervious, Inflow Depth = 6.12" for 100-Year event
Inflow = 14.57 cfs @ 12.02 hrs, Volume= 37,857 cf
Outflow = 3.78 cfs @ 12.24 hrs, Volume= 37,855 cf, Atten= 74%, Lag= 13.1 min
Primary = 3.78 cfs @ 12.24 hrs, Volume= 37,855 cf
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Peak Elev= 3,010.99' @ 12.24 hrs Surf.Area= 7,783 sf Storage= 15,859 cf
Plug -Flow detention time=121.8 min calculated for 37,855 cf (100% of inflow)
Center -of -Mass det. time= 121.7 min ( 912.2 - 790.5 )
Volume Invert Avail.Storage Storage Description
#1 3,008.50' 29,024 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
3,008.50 5,016 0 0
3,009.00 5,551 2,642 2,642
3,010.00 6,644 6,098 8,739
3,011.00 7,798 7,221 15,960
3,011.50 8,398 4,049 20,009
3,012.00 9,011 4,352 24,362
3,012.50 9,640 4,663 29,024
Device Routing Invert Outlet Devices
#1 Secondary 3,011.50' 10.0' long x 4.0' breadth EO Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66
2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32
#2 Primary 3,008.50' 10.0" Vert. Orifice/Grate C= 0.600
#3 Device 2 3,011.00' 4.0' long x 0.5' breadth Throat Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4 Device 2 3,009.50' 10.0" W x 10.0" H Vert. Orifice/Grate C= 0.600
#5 Device 2 3,008.50' 4.0" W x 4.0" H Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=3.78 cfs @ 12.24 hrs HW=3,010.99' (Free Discharge)
t =Orifice/Grate (Orifice Controls 3.78 cfs @ 6.93 fps)
3=Throat Weir ( Controls 0.00 cfs)
=Orifice/Grate (Passes < 3.44 cfs potential flow)
=Orifice/Grate (Passes < 0.81 cfs potential flow)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=3,008.50' (Free Discharge)
t1=E0 Weir ( Controls 0.00 cfs)

Foscoe NC_Broadway Group 11-17-16 Type/1 24-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD®10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 38
Pond 1P: Detention Basin
Hydrograph
❑Inflow
❑ OuMow
Inflow Area=74I r sf o Primary ary
Peak Elev=3,010.99'
Storage=15,859 cf
Time (hours)

Foscoe NC Broadway Group 11-17-16 Type/1 24-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 39
Summary for Pond 2P: Access Road Swale Basin
Inflow Area =
21,352 sf,
36.40% Impervious,
Inflow Depth = 5.53" for 100-Year event
Inflow =
4.80 cfs @
11.96 hrs, Volume=
9,842 cf
Outflow =
2.08 cfs @
12.05 hrs, Volume=
9,842 cf, Atten= 57%, Lag= 5.5 min
Primary =
1.21 cfs @
12.05 hrs, Volume=
9,415 cf
Secondary =
0.88 cfs @
12.05 hrs, Volume=
428 cf
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs / 2
Peak Elev= 3,009.38' @ 12.05 hrs Surf.Area= 3,139 sf Storage= 2,823 cf
Plug -Flow detention time= 24.2 min calculated for 9,841 cf (100% of inflow)
Center -of -Mass det. time= 24.2 min ( 823.6 - 799.3 )
Volume Invert Avail.Storage Storage Description
#1 3,007.50' 5,395 cf Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
3,007.50 600 0 0
3,008.00 980 395 395
3,009.00 1,960 1,470 1,865
3,010.00 5,100 3,530 5,395
Device Routing Invert Outlet Devices
#1 Secondary 3,009.20' 5.0' long x 4.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66
2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32
#2 Primary 3,007.50' 6.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=1.21 cfs @ 12.05 hrs HW=3,009.38' (Free Discharge)
t2=Orifice/Grate (Orifice Controls 1.21 cfs @ 6.14 fps)
Secondary OutFlow Max=0.87 cfs @ 12.05 hrs HW=3,009.38' (Free Discharge)
1=13road-Crested Rectangular Weir(Weir Controls 0.87 cfs @ 1.00 fps)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD® 10.00-15 s/n 02540 ©2015 HydroCAD Software Solutions LLC Page 40
Pond 2P: Access Road Swale Basin
Hydrograph
1f ® Inflow
44eo -N1 ❑ Outflow
0
u.
i
Inflow Area=21,352 sf
o Secmondary
Peak Elev=3,009.38'
Storage=2,823 cf
cls
32 34 36 38 40 42 44 4648 50 52 54 56 506062 64 66 68 70 72
Time (hours)

Foscoe NC_Broadway Group 11-17-16 Type 1124-hr 100-Year Rainfall=7.90"
Prepared by CEI Engineering Associates Inc Printed 11/18/2016
HydroCAD@ 10.00-15 s/n 02540 @ 2015 HydroCAD Software Solutions LLC Page 41
Summary for Link UT: Undetained Total
Inflow Area = 9,172 sf, 48.71% Impervious, Inflow Depth = 5.86" for 100-Year event
Inflow = 2.03 cfs @ 11.96 hrs, Volume= 4,482 cf
Primary = 2.03 cfs @ 11.96 hrs, Volume= 4,482 cf, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Link UT: Undetained Total
Hydrograph
F13 Inflaw
10 Pnmary
Time (hours)