SW3200201_Calcs_20200511

BREC, P.A. Dollar General – Store #21867 1
DOLLAR GENERAL – STORE #21867
NEWTON, NC
HYDROLOGIC AND HYDRAULIC ANALYSIS REPORT

Prepared By:
BREC, P.A.
1520 Meadowview Drive
Wilkesboro, NC 28697
NCBELS Firm #C-3448
[phone]
[e-mail]
Prepared For:
Teramore Development, LLC
Joe Strickland, Dir. of Ops., NC
214 Klumac Rd., Ste. 101
Salisbury, NC 28144
[phone]
[e-mail]
Project Site:
TBD Providence Mill Road
Newton, NC

4 May 2020

Justin Church, PE
Principal Engineer

BREC, P.A. Dollar General – Store #21867 2
Table of Contents
1.0 General Information ........................................................................................ 3 
2.0 Methodology ................................................................................................... 3 
2.1 Curve Number Calculations 3 
2.2 Time of Concentration Calculations 4 
2.3 Rainfall Data 5 
2.4 Pipe Design 6 
2.4.1 Outlet Design 6 
2.5 Hydrology Calculations 7 
2.6 Modified Curve Number Calculations 8 
2.7 Sand Filter Design 8 
2.7.1 Chamber and Filter Sizing 9 
2.7.2 Underdrain Sizing 9 
2.7.3 Anti-floatation Calculations 10 
3.0 Results .......................................................................................................... 11 
Appendix ............................................................................................................. 12 

List of Figures
Figure 1 - System Storage of First Flush ............................................................ 11 
List of Tables
Table 1 - Pre-Construction Drainage Area ............................................................ 3 
Table 2 - Post-Construction Drainage Areas ........................................................ 4 
Table 3 - Pre-Construction ToC ............................................................................ 5 
Table 4 - Post-Construction ToC ........................................................................... 5 
Table 5 - NOAA Rainfall Depths ........................................................................... 5 
Table 6 - NOAA Rainfall Intensity ......................................................................... 5 
Table 7 - Composite Rational Coefficients ............................................................ 6 
Table 8 - Pipe Design Summary ........................................................................... 6 
Table 9 - Riprap Outlet Stone Sizing ..................................................................... 7 
Table 10 - Riprap Apron Dimensions .................................................................... 7 
Table 11 - Modified SCS Curve Numbers ............................................................. 8 
Table 12 - Sand Filter State-Storage .................................................................... 9 
Table 13 - Pipe Design Table ............................................................................. 12 

BREC, P.A. Dollar General – Store #21867 3
1.0 General Information

This document contains hydrologic and hydraulic calculations demonstrating
compliance with post-construction state and local stormwater regulations for the
construction of a 9,100 𝑓𝑡ଶ Dollar General retail store at the intersection of
Providence Mill Road and NC Highway 16 in Newton, NC. Specifically, regulations
for this area require water quality treatment of the first flush ሺ1"ሻ storm.

The subject tract is composed of a partially wooded vacant lot. No jurisdictional
features are present on the site. The site is almost entirely composed of CaB soils
which are hydrologic soil group A. Post construction stormwater requirements will
be satisfied with an above ground sand filter which is approved by NCDEQ as a
primary stormwater control measure (SCM).
2.0 Methodology

One pre-construction drainage area and six post-construction drainage areas
covering the subject tract and adjacent off-site areas were identified. See
plansheets for delineation. The pre-construction drainage area outlets at
OUTFALL-1 located at an existing NCDOT drainage ditch in the northeast corner
of the site. All proposed impervious areas are routed to the sand filter for treatment
prior to discharge. Two drainage areas, POST-CON:4 and POST-CON:6, are not
routed to the sand filter due to topographic limitations.

2.1 Curve Number Calculations

Composite SCS curve numbers were calculated as weighted averages using
values of 49 for fair grass coverage (pre-construction) and 39 for good grass
coverage (post-construction, maintained), 30 for wooded areas, and 98 for
impervious surfaces in HSG A soils.

For pre-construction drainage areas, the composite curve number is calculated as:

𝐶𝑁௖௢௠௣೛ೝ೐ ൌ ሺ𝐴௜௠௣ 𝑥 98 ൅𝐴௚௥௔௦௦ 𝑥 49 ൅𝐴௪௢௢ௗ௘ௗ 𝑥 30ሻ
𝐴௧௢௧௔௟

Table 1 - Pre-Construction Drainage Area
Name 𝑨𝒕𝒐𝒕𝒂𝒍
(acres)
𝑨𝒊𝒎𝒑
(acres)
𝑨𝒈𝒓𝒂𝒔𝒔
(acres)
𝑨𝒘𝒐𝒐𝒅𝒆𝒅
(acres) 𝑪𝑵𝒄𝒐𝒎𝒑𝒑𝒓𝒆
PRE-CON:1 2.62 0.19 1.42 1.01 45.3

BREC, P.A. Dollar General – Store #21867 4
For post-construction drainage areas, the composite curve number is calculated
as:
𝐶𝑁௖௢௠௣௢௦௜௧௘೛೚ೞ೟ ൌ ሺ𝐴௜௠௣ 𝑥 98 ൅𝐴௚௥௔௦௦ 𝑥 39 ൅𝐴௪௢௢ௗ௘ௗ 𝑥 30ሻ
𝐴௧௢௧௔௟

Table 2 - Post-Construction Drainage Areas
Name 𝑨𝒕𝒐𝒕𝒂𝒍
(acres)
𝑨𝒊𝒎𝒑
(acres)
𝑨𝒈𝒓𝒂𝒔𝒔
(acres)
𝑨𝒘𝒐𝒐𝒅𝒆𝒅
(acres) 𝑪𝑵𝒄𝒐𝒎𝒑𝒑𝒐𝒔𝒕
POST-CON:1+ 0.21 0.21 0.00 0.00 98.0
POST-CON:2+ 0.28 0.19 0.09 0.00 79.6
POST-CON:3+ 0.30 0.28 0.02 0.00 93.5
POST-CON:4+ 0.20 0.00 0.20 0.00 39.0
POST-CON:5 0.95 0.13 0.82 0.00 47.2
POST-CON:6 1.48 0.07 1.41 0.00 41.6

+ Routed through sand filter prior to discharge.

2.2 Time of Concentration Calculations

Time of concentration values for vegetated drainage areas were evaluated using
the segmental, lag, and FAA equations with a design value selected from the range
produced by these equations. All majority impervious drainage areas less than
one acre were assigned a design time of concentration value of five minutes.

𝑇௖೗ೌ೒ ሺ௛௥ሻ ൌ 𝑙଴.଼ ሺ𝑆൅1ሻ଴.଻
1,140√𝑌

𝑙ൌ𝑓𝑙𝑜𝑤 𝑙𝑒𝑛𝑔𝑡ℎ ሺ𝑓𝑡ሻ
𝑌ൌ𝑎𝑣𝑔.𝑤𝑎𝑡𝑒𝑟𝑠ℎ𝑒𝑑 𝑙𝑎𝑛𝑑 𝑠𝑙𝑜𝑝𝑒 ሺ%ሻ
𝑆ൌ𝑚𝑎𝑥 𝑟𝑒𝑡𝑒𝑛𝑡𝑖𝑜𝑛 𝑝𝑜𝑡𝑒𝑛𝑡𝑖𝑎𝑙 ൌ ൬1,000
𝐶𝑁൰ െ 10

𝑇௖ಷಲಲሺ௠௜௡ሻ ൌ ൫1.8ሺ1.1 െ𝑐ሻ√𝑙൯
𝑌ଵ
ଷ

𝑐ൌ𝑟𝑎𝑡𝑖𝑜𝑛𝑎𝑙 𝑐𝑜𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑡

𝑇௖ ௦௘௚௠௘௡௧௔௟ ሺℎ𝑟ሻ ൌ𝑇௦௛௘௘௧ ൅𝑇௦௖௙
𝑇௦௛௘௘௧ ൌ 0.007ሺ𝑛𝑙ሻ଴.଼
ඥ𝑃ଶ𝑆଴.ସ

BREC, P.A. Dollar General – Store #21867 5
𝑛 ൌ 𝑀𝑎𝑛𝑛𝑖𝑛𝑔
ᇱ 𝑠 𝑐𝑜𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑡
𝑃ଶ ൌ 2𝑦𝑟,24 ℎ𝑟 𝑟𝑎𝑖𝑛𝑓𝑎𝑙𝑙 ሺ𝑖𝑛ሻ
𝑆ൌ𝑠𝑙𝑜𝑝𝑒 ൬𝑓𝑡
𝑓𝑡൰

𝑇௦௖௙ ൌ 𝑙
3,600𝑉

𝑉 ൌ 𝑠ℎ𝑎𝑙𝑙𝑜𝑤 𝑐𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑒𝑑 𝑓𝑙𝑜𝑤 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 ൬𝑓𝑡
𝑠൰

Table 3 - Pre-Construction ToC
Name 𝑳𝒆𝒏𝒈𝒕𝒉
ሺ𝒇𝒕ሻ
𝑺𝒍𝒐𝒑𝒆
ሺ𝒇𝒕ሻ
𝑻𝒄ି𝒄𝒂𝒍𝒄
ሺ𝒎𝒊𝒏ሻ
𝑻𝒄ି𝒂𝒔𝒔𝒖𝒎𝒆𝒅
ሺ𝒎𝒊𝒏ሻ
PRE-CON:1 190 0.02 14-18 16

Table 4 - Post-Construction ToC
Name 𝑳𝒆𝒏𝒈𝒕𝒉
ሺ𝒇𝒕ሻ
𝑺𝒍𝒐𝒑𝒆
ሺ𝒇𝒕ሻ
𝑻𝒄ି𝒄𝒂𝒍𝒄
ሺ𝒎𝒊𝒏ሻ
𝑻𝒄ି𝒂𝒔𝒔𝒖𝒎𝒆𝒅
ሺ𝒎𝒊𝒏ሻ
POST-CON:1 - - - 5
POST-CON:2 - - - 5
POST-CON:3 - - - 5
POST-CON:4 - - - 5
POST-CON:5 135 0.02 9-15 11
POST-CON:6 - - - 5

2.3 Rainfall Data

Rainfall data was taken from NOAA Atlas 14, Volume 2, Version 3 for Concord,
NC. Rainfall depths for each design storm are summarized below.

Table 5 - NOAA Rainfall Depths
Storm 𝑹𝒂𝒊𝒏𝒇𝒂𝒍𝒍 𝑫𝒆𝒑𝒕𝒉 ሺ𝒊𝒏ሻ
First Flush 1.00
1 Year, 24 Hour 2.92

Table 6 - NOAA Rainfall Intensity
Storm 𝑹𝒂𝒊𝒏𝒇𝒂𝒍𝒍 𝑰𝒏𝒕𝒆𝒏𝒔𝒊𝒕𝒚 ሺ𝒊𝒏/𝒉𝒓ሻ
10 Year, 5 Min 7.01

BREC, P.A. Dollar General – Store #21867 6
2.4 Pipe Design

A composite post-construction rational coefficient was also assigned to each post
construction drainage area as needed for pipe design. The composite rational
coefficients were calculated using individual coefficients of 0.86 for impervious
surfaces, 0.10 for grass surfaces, and 0.08 for wooded areas in HSG A soils.

𝐶௖௢௠௣ ൌ 𝐴௜௠௣ 𝑥 0.86 ൅𝐴௚௥௔௦௦ 𝑥 0.10 ൅𝐴௪௢௢ௗ௘ௗ 𝑥 0.08
𝐴௧௢௧௔௟

Table 7 - Composite Rational Coefficients
Name 𝑪𝒄𝒐𝒎𝒑 𝑸𝟏𝟎 ቆ𝒇𝒕𝟑
𝒔ቇ
POST-CONSTRUCTION:1 0.86 1.27
POST-CONSTRUCTION:2 0.62 1.22
POST-CONSTRUCTION:3 0.80 1.68
POST-CONSTRUCTION:4 0.10 0.14
POST-CONSTRUCTION:5 0.21 1.08
POST-CONSTRUCTION:6 0.13 1.35

The 10 year rational discharges were used to size pipes by solving Manning’s
equation iteratively for the normal depth.

Table 8 - Pipe Design Summary
NAME 𝑫𝑰𝑨 ሺ𝒊𝒏ሻ 𝑸ௗ௘௦௜௚௡  ቀ𝒇𝒕𝟑
௦ ቁ 𝑽𝒅𝒆𝒔𝒊𝒈𝒏 ൬𝑓𝑡
𝑠൰ 
PIPE‐1 15 1.1 5.1 
PIPE‐2 15 1.2 5.6 
PIPE‐3 15 2.9 4.2 
PIPE‐4 18 4.3 4.9 

See Appendix for complete pipe design table.

2.4.1 Outlet Design

Outlet design for PIPE-1, PIPE-3, and PIPE-4 was taken from Chapter 10 of HEC-
14. Riprap 𝐷ହ଴ was calculated as:

𝐷ହ଴ ൌ 0.2𝐷ቆ𝑄ௗ௘௦௜௚௡
ඥ𝑔𝐷ଶ.ହ ቇ
ସ
ଷ
൬ 𝐷
𝑇𝑊൰
Where,

BREC, P.A. Dollar General – Store #21867 7
𝐷ହ଴ ൌ𝑟𝑖𝑝𝑟𝑎𝑝 𝑠𝑖𝑧𝑒,ሺ𝑓𝑡ሻ
𝑄ௗ௘௦௜௚௡ ൌ 𝐷𝑒𝑠𝑖𝑔𝑛 𝑑𝑖𝑠𝑐ℎ𝑎𝑟𝑔𝑒 ቆ𝑓𝑡ଷ
𝑠ቇ
𝐷ൌ𝑃𝑖𝑝𝑒 𝑑𝑖𝑎𝑚𝑒𝑡𝑒𝑟,ሺ𝑓𝑡ሻ
𝑇𝑊 ൌ 𝑇𝑎𝑖𝑙𝑤𝑎𝑡𝑒𝑟 𝑑𝑒𝑝𝑡ℎ,ሺ𝑓𝑡ሻ
𝑔 ൌ 𝑔𝑟𝑎𝑣𝑖𝑡𝑎𝑡𝑖𝑜𝑛𝑎𝑙 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛 ൬32.2 𝑓𝑡
𝑠ଶ ൰

Substituting the corresponding pipe diameters and design discharges into the
equation above for PIPE-1, PIPE-3, and PIPE-4 yields:

Table 9 - Riprap Outlet Stone Sizing
NAME 𝑫𝑰𝑨 ሺ𝒊𝒏ሻ 𝑸𝒅𝒆𝒔𝒊𝒈𝒏 ቀ𝒇𝒕𝟑
𝒔ቁ 𝑫𝟓𝟎𝒄𝒂𝒍𝒄 ሺ𝒊𝒏ሻ 𝑫𝟓𝟎𝒅𝒆𝒔𝒊𝒈𝒏 ሺ𝒊𝒏ሻ
PIPE‐1 15 1.1 0.60 5.0 
PIPE‐3 15 2.9 2.30 5.0 
PIPE‐4 18 4.3 3.60 5.0 

A minimum 𝐷ହ଴ of 5 𝑖𝑛𝑐ℎ𝑒𝑠 was chosen for each pipe which corresponds to
NCDOT Class A stone. Given the design 𝐷ହ଴ , the dimensions of the apron were
taken from Table 10.1 equations from HEC 141.

𝐿௔ ൌ𝐴𝑝𝑟𝑜𝑛 𝑙𝑒𝑛𝑔𝑡ℎ ሺ𝑓𝑡ሻ ൌ 4𝐷
𝐷௔ ൌ𝐴𝑝𝑟𝑜𝑛 𝑑𝑒𝑝𝑡ℎ ሺ𝑓𝑡ሻ ൌ 3.5𝐷ହ଴
𝑊ଵ ൌ 𝑈𝑝𝑝𝑒𝑟 𝑤𝑖𝑑𝑡ℎ ሺ𝑓𝑡ሻ ൌ 3𝐷
𝑊ଶ ൌ𝐿𝑜𝑤𝑒𝑟 𝑤𝑖𝑑𝑡ℎ ሺ𝑓𝑡ሻ ൌ 3𝐷൅൬2
3൰ 𝐿௔

Table 10 - Riprap Apron Dimensions
NAME 𝑫𝑰𝑨 ሺ𝒊𝒏ሻ 𝑳𝒂 ሺ𝒇𝒕ሻ 𝑫𝒂 ሺ𝒇𝒕ሻ 𝑾𝟏 ሺ𝒇𝒕ሻ 𝑾𝟐 ሺ𝒇𝒕ሻ 
PIPE‐1 15 5.0 1.5 3.8 7.1 
PIPE‐3 15 5.0 1.5 3.8 7.1 
PIPE‐4 18 6.0 1.5 4.5 8.5 

2.5 Hydrology Calculations

The water quality volume ሺ𝑊𝑄𝑉ሻ required to be treated from the first flush was
calculated using the Schueler method outlined in the NCDEQ Stormwater Design
Manual2. The Schueler method utilizes the following equations:

1 http://www.fhwa.dot.gov/engineering/hydraulics/pubs/06086/hec14ch10.cfm
2 https://deq.nc.gov/sw-bmp-manual

BREC, P.A. Dollar General – Store #21867 8
𝑅௩ ൌ 0.05 ൅ 0.9𝐼஺
𝑊𝑄𝑉 ൌ 3630𝑅஽ 𝑅௩ 𝐴

Where 𝐼஺ is the impervious fraction of the drainage area, 𝑅௩ is a runoff coefficient,
𝑅஽ is the rainfall depth, 𝐴 is the drainage area, and 𝑊𝑄௩ is the runoff volume. The
following parameters are used for the drainage routed to the sand filter.

𝐼௔ ൌ 0.69
𝑅௩ ൌ 0.05 ൅ 0.9ሺ0.43ሻ ൌ 0.67

𝑅஽ ൌ 1.0 𝑖𝑛𝑐ℎ
𝐴ൌ0.99 𝑎𝑐𝑟𝑒𝑠

𝑊𝑄𝑉 ൌ 3,630ሺ1.0ሻሺ0.67ሻሺ0.99ሻ ൌ 2,392 𝑓𝑡ଷ
𝑊𝑄𝑉௔ௗ௝ ൌ 0.75𝑊𝑄௩ ൌ 0.75ሺ2,392ሻ ൌ 1,794 𝑓𝑡ଷ

2.6 Modified Curve Number Calculations

To route the 𝑊𝑄𝑉 through the sand filter, it is necessary to calculate a modified
SCS curve number to avoid underrepresenting the first flush. The modified curve
number is calculated as follows:

𝐶𝑁௠ ൌ 1000/ቂ10 ൅ 5𝑅஽ ൅ 10𝑅௩ െ 10ඥ𝑅௩ଶ ൅ 1.25𝑅௩ 𝑅஽ ቃ

The modified curve numbers were used to route the first flush using an SCS 6 hour
balanced storm distribution. The remaining design storms were routed with
standard curve numbers and an SCS type II 24 hour storm distribution.

Table 11 - Modified SCS Curve Numbers
Name 𝑹𝒗 𝑪𝑵𝒎𝒐𝒅
POST-CON:1 0.95 99.57
POST-CON:2 0.67 96.54
POST-CON:3 0.88 98.94
POST-CON:4 0.05 77.22
POST-CON:5 0.18 85.08
POST-CON:6 0.09 80.47

2.7 Sand Filter Design

The combined area of the sediment chamber and sand chamber is determined
from the relationship of the max water depth observed during the water quality
event, 𝐻௠௔௫ , and the adjusted water quality volume. The design value for 𝐻௠௔௫
was chosen as 1.0 𝑓𝑡. When coupled with the adjusted water quality volume,

BREC, P.A. Dollar General – Store #21867 9
𝑊𝑄𝑉௔ௗ௝ ൌ 0.75𝑊𝑄𝑉 ൌ 1,794 𝑓𝑡ଷ , the resulting stage storage for the sand filter is
summarized below.

Table 12 - Sand Filter State-Storage
𝑺𝒕𝒂𝒈𝒆
ሺ𝒇𝒕ሻ
𝑬𝒍𝒆𝒗𝒂𝒕𝒊𝒐𝒏
ሺ𝒇𝒕ሻ
𝑨𝒓𝒆𝒂
൫𝒇𝒕𝟐൯
𝑺𝒆𝒅𝒊𝒎𝒆𝒏𝒕 𝑽𝒐𝒍
൫𝒇𝒕𝟑൯
𝑭𝒊𝒍𝒕𝒆𝒓 𝑽𝒐𝒍
൫𝒇𝒕𝟑൯
𝑻𝒐𝒕𝒂𝒍 𝑽𝒐𝒍
൫𝒇𝒕𝟑൯
0.0 1032 1,776 0 0 0
1.0 1033 2,423 1,049 1,051 2,100
2.0 1034 3,151 2,440 2,446 4,887
3.0 1035 3,960 4,216 4,226 8,442
4.0 1036 4,850 6,416 6,43` 12,847

At 𝐸𝑙𝑒𝑣𝑎𝑡𝑖𝑜𝑛 ൌ 1033 𝑓𝑡,𝐻௠௔௫ ൌ 1.0 𝑓𝑡, 𝑊𝑄𝑉௣௥௢௩௜ௗ௘ௗ ൌ 2,100 𝑓𝑡ଷ ൐𝑊𝑄𝑉௔ௗ௝ .
2.7.1 Chamber and Filter Sizing

The sediment chamber and filter chamber are equally sized. The sediment
chamber has an additional 1.0 𝑓𝑡 depression to assist with maintenance and
primary sediment deposition; however, this added volume is not considered in
calculations to meet minimum design criteria requirements. Given the filter
chamber area, the sand media area, 𝐴௦௔௡ௗ , was selected as 375 𝑓𝑡ଶ . This value
maximizes the available filter chamber area and preserves an easily installable
geometric shape for the sand media while providing space for installation of the
outlet structure outside of the sand media and preventing the sand media from
being installed adjacent to the toe of slope grading. Discharge through the sand
media is governed by Darcy’s Law.

𝑄௦௔௡ௗ ൌ 𝐴௦௔௡ௗ 𝑘൫ℎ௙ ൅𝑑௙ ൯
𝑑௙

Where,
𝐴௦௔௡ௗ ൌ𝑆𝑎𝑛𝑑 𝑚𝑒𝑑𝑖𝑎 𝑠𝑢𝑟𝑓𝑎𝑐𝑒 𝑎𝑟𝑒𝑎 ሺ𝑓𝑡ଶ ሻ ൌ 375 𝑓𝑡ଶ
𝑘ൌ𝑆𝑎𝑛𝑑 𝑚𝑒𝑑𝑖𝑎 𝑝𝑒𝑟𝑚𝑒𝑎𝑏𝑖𝑙𝑖𝑡𝑦 ൬ 𝑓𝑡
𝑑𝑎𝑦൰ ൌ 4.0 𝑓𝑡
𝑑𝑎𝑦
𝑑௙ ൌ𝑆𝑎𝑛𝑑 𝑚𝑒𝑑𝑖𝑎 𝑑𝑒𝑝𝑡ℎ ሺ𝑓𝑡ሻ ൌ 1.5 𝑓𝑡
ℎ௙ ൌ𝐻𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟 𝑎𝑏𝑜𝑣𝑒 𝑠𝑎𝑛𝑑 𝑚𝑒𝑑𝑖𝑎

2.7.2 Underdrain Sizing

Drawdown time is calculated as:

𝑡ൌ 𝑊𝑄𝑉𝑑௙
𝑘൫ℎ௔ ൅𝑑௙ ൯𝐴௦௔௡ௗ
ൌ 2,392ሺ1.5ሻ
4.0ሺ0.5 ൅ 1.5ሻ375 ൌ 28.7 ℎ𝑜𝑢𝑟𝑠

BREC, P.A. Dollar General – Store #21867 10
Discharge rate is calculated as:

𝑄௨௡ௗ௘௥ௗ௥௔௜௡ ൌ 𝑊𝑄𝑉
𝑡ൌ 2,392
28.7 ൌ 0.023 𝑓𝑡ଷ
𝑠

After applying a safety factor of 10,

𝑄௦௔௡ௗ ൌ 10𝑄௨௡ௗ௘௥ௗ௥௔௜௡ ൌ 0.23 𝑓𝑡ଷ
𝑠

The diameter of a single pipe is calculated as:

𝐷ൌ16 ൬𝑛𝑄௦௔௡ௗ
√𝑆൰
ଷ
଼
Where,

𝑛 ൌ 𝑀𝑎𝑛𝑛𝑖𝑛𝑔
ᇱ 𝑠 𝑟𝑜𝑢𝑔ℎ𝑛𝑒𝑠𝑠 𝑓𝑜𝑟 𝑝𝑖𝑝𝑒
𝑆 ൌ 𝑝𝑖𝑝𝑒 𝑠𝑙𝑜𝑝𝑒

𝐷ൌ16 ቆ0.011ሺ0.23ሻ
√0.005 ቇ
ଷ
଼ ൌ 4.6 𝑖𝑛𝑐ℎ𝑒𝑠

Per Table 1 of Section A-5 of the NCDEQ Stormwater Design Manual, use (2) 4
inch pipes.

2.7.3 Anti‐floatation Calculations

The outlet structure is a 5.0 𝑓𝑡 tall 3 𝑓𝑡 𝑥 3 𝑓𝑡 precast concrete box with 6 𝑖𝑛 side
and bottom wall thicknesses. Including concrete and reinforcing steel, the
structure has an empty mass of 𝑀௢௨௧௟௘௧೐೘೛೟೤ ൌ 5,184 𝑙𝑏.

Assuming the total height of the box is exposed to buoyant forces, the volume of
water displaced by the box is calculated from the outside dimensions.
𝑉௕௢௫ೢೌ೟೐ೝ ൌ 4.0 𝑓𝑡 𝑥 4.0 𝑓𝑡 𝑥 5.50 𝑓𝑡 ൌ 88.0 𝑓𝑡ଷ

The buoyant force on the box is defined from the hydraulic forces acting

𝐹௕ ൌ𝑉௕௢௫ೢೌ೟೐ೝ 𝜌௪ ൌ 88.0 𝑓𝑡ଷ 𝑥 62.4 𝑙𝑏
𝑓𝑡ଷ ൌ 5,491 𝑙𝑏

BREC, P.A. Dollar General – Store #21867 11
Additional mass was added to the outlet structure by pouring a 6 𝑖𝑛 concrete slab
over the bottom.

𝑀௢௨௧௟௘௧೟೚೟ೌ೗ ൌ 5,184 𝑙𝑏 ൅ ሺ3 𝑓𝑡ሻሺ3 𝑓𝑡ሻሺ0.5 𝑓𝑡ሻ ൬150 𝑙𝑏
𝑓𝑡ଷ ൰ ൌ 5,895 𝑙𝑏 ൐ 𝐹௕

3.0 Results

The first flush ሺ1"ሻ storm is routed through the sand filter and reaches a max
storage depth of 0.93 𝑓𝑡 which does not exceed the design 𝐻௠௔௫ ൌ 1.0 𝑓𝑡. The
water quality volume is discharged over a period of 30.0 ℎ𝑜𝑢𝑟𝑠.

Figure 1 - System Storage of First Flush

Storage: System (POST-CON-ROUTING-BALANCED 2020-01-28 16:27:58)Storage (ft³)2100
2000
1900
1800
1700
1600
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
Time (hrs)
454035302520151050
BREC, P.A. Dollar General – Store #21867 12 Appendix Table 133 - Pipe Design Table NAME DIA (IN) INV UP HGL UP INV DOWN HGL DOWN LEN (FT) S (FT/FT) n Q MAX (CFS) Q DESIGN (CFS) V DESIGN (FT/S) PIPE‐1 15 1036.0 1036.3 1034.6 1034.9 79.1 0.018 0.012 9.3 1.1 5.1 PIPE‐2 15 1036.1 1036.4 1034.6 1034.9 71.0 0.021 0.012 10.2 1.2 5.6 PIPE‐3 15 1034.5 1035.2 1033.5 1034.2 196.7 0.005 0.012 5.0 2.9 4.2 PIPE‐4 18 1028.8 1029.5 1028.5 1029.3 43.8 0.006 0.012 8.6 4.3 4.9 
Post -construction First Flush
BREC, P.A. Dollar General — Store #21867 12

Project Description
File Name..................................................................
POST-CON-ROUTING-BALANCED.SPF
Description----------------------------------------------------------------
R:\Shared
Folders\PROJECTS\BREC\PROJ
ECTS\316_TERAMORE_DEVELOPM ENT\3160622019_DOLLAR_GE
Project Options
FlowUnits------------------------------------------------------------------
CFS
Elevation Type
Elevation
Hydrology Method .
SCS TR-55
Time of Concentration (TOC) Method .
User -Defined
Link Routing Method
Kinematic Wave
Enable Overflow Ponding at Nodes
YES
Skip Steady State Analysis Time Periods
NO
Analysis Options
Start Analysis On .
Jan 28, 2020
00-00-00
End Analysis On .
Jan 30, 2020
00-00-00
Start Reporting On .
Jan 28, 2020
00-00-00
Antecedent Dry Days
0
days
Runoff (Dry Weather) Time Step ------------------------------
0 01-00-00
days hh:mm:ss
Runoff (Wet Weather) Time Step -----------------------------
0 00-05-00
days hh:mm:ss
Reporting Time Step -------------------------------------------------
0 00-00-15
days hh:mm:ss
Routing Time Step ----------------------------------------------------
15
seconds
Number of Elements
Qty
Rain Gages
1
Subbasins
6
Nodes
4
Junctions
2
Outfalls
1
Flow Diversions
0
Inlets
0
Storage Nodes
1
Links
5
Channels
0
Pipes
2
Pumps
0
Orifices
1
Weirs
1
Outlets
1
Pollutants
0
Land Uses
0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
1 NEWTON Time Series 11N-6HR-BALANCED Cumulative inches 0.00

Subbasin Summary
SN Subbasin Area Peak Rate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac)
(in)
(in)
(ac-in)
(cfs)
(days hh:mm:ss)
1 {POST-CON}.POST-CON
: 1 021
484.00
99.57
1.00
0.95
0.19
0.43
0 00-05-00
2 {POST-CON}.POST-CON
: 2 028
484.00
96.54
1.00
0.67
0.19
0.47
0 00-05-00
3 {POST-CON}.POST-CON
: 3 0.30
484.00
98.94
1.00
0.88
026
0.61
0 00-05-00
4 {POST-CON}.POST-CON
: 4 020
484.00
7722
1.00
0.05
0.01
0.01
0 00-05-00
5 {POST-CON}.POST-CON
: 5 0.95
484.00
85.08
1.00
0.17
0.16
028
0 00-10-00
6 {POST-CON}.POST-CON
: 6 1.48
484.00
80.47
1.00
0.09
0.13
0.18
0 00-05-00

Node Summary
SN Element
Element
Invert Ground/Rim
Initial Surcharge Ponded Peak Max HGL
Max
Min
Time of
ID
Type
Elevation
(Max)
Water
Elevation
Area Inflow
Elevation Surcharge Freeboard
Peak
Elevation
Elevation
Attained
Depth
Attained
Flooding
Attained
Occurrence
(ft)
(ft)
(ft)
(ft)
(ft') (cfs)
(ft)
(ft)
(ft) (days hh:mm)
1 SCM-RISER
Junction
1028.75
1036.00
1028.75
0.00
0.00 0.03
1028.81
0.00
7.19
0 00:00
2 SITE -JUNCTION -VIRTUAL
Junction
1028.50
1036.00
1028.50
0.00
0.00 0.49
1028.59
0.00
7.41
0 00:00
3 OUTFALL
Outfall
1022.00
0.49
1022.09
4 SAND -FILTER
Storage Node
1032.00
1036.00
1032.00
0.00 1.51
1032.93

Link Summary
SN Element
Element From
To (Outlet)
Length
Inlet
Outlet Average Diameter or
Manning's Peak Design Flow
Peak Flow/ Peak Flow Peak Flow
Peak Flow
Total Time Reported
ID
Type
(Inlet)
Node
Invert
Invert Slope
Height
Roughness Flow
Capacity
Design Flow
Velocity
Depth
Depth/
Surcharged Condition
Node
Elevation
Elevation
Ratio
Total Depth
Ratio
(ft)
(ft)
(ft) ( % )
(in)
(cfs)
(cfs)
(ft/sec)
(ft)
(min)
1 SCM-BARREL
Pipe
SCM-RISER
SITE -JUNCTION -VIRTUAL
45.00
1028.75
1028.50 0.5600
18.000
0.0120 0.03
8.48
0.00
2.95
0.06
0.04
0.00 Calculated
2 SITE -LINK -VIRTUAL
Pipe
SITE-JUNCTION-VIRTUALOUTFALL
2000.
1028.50
1022.00 32.5000
18.000
0.0120 0.49
64.87
0.01
10.79
0.09
0.06
0.00 Calculated
3 PRINCIPAL -SPILLWAY Orifice
SAND -FILTER
SCM-RISER
1032.00
1028.75
36.000
0.00
4 SAND -MEDIA
Outlet
SAND -FILTER
SCM-RISER
1032.00
1028.75
0.03
5 EM-SPILLWAY
Weir
SAND -FILTER
SITE -JUNCTION -VIRTUAL
1032.00
1028.50
0.00

Subbasin Hydrology
Subbasin : {POST-CON}.POST-CON : 1
Input Data
Area(ac)----------------------------------------------------- 0.21
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 99.57
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.21 - 99.57
Composite Area & Weighted CN 0.21 99.57
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 1.00
Total Runoff (in) ------------------------------------------ 0.95
Peak Runoff (cfs)---------------------------------------- 0.43
Weighted Curve Number ............................ 99.57
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 1
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1
0.9
0.8
0.7
06
0.5
0.4
0.3
0.2
0.1
0.46
0.44
0.42
0.4
038
0.36
0.34
0.32
0.3
0.28
0.26
-- 0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 2
Input Data
Area(ac)----------------------------------------------------- 0.28
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 96.54
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.28 - 96.54
Composite Area & Weighted CN 0.28 96.54
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 1.00
Total Runoff (in) ------------------------------------------ 0.67
Peak Runoff (cfs)---------------------------------------- 0.47
Weighted Curve Number ............................ 96.54
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 2
2.4
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
'E 1.1
0 1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.5
0.48
0.46
044
0.42
0.4
0.38
0.36
0.34
0.32
0.3
N 0.28
0.26
0.24
0.22
0.2
0 18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 3
Input Data
Area(ac)----------------------------------------------------- 0.30
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 98.94
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.30 - 98.94
Composite Area & Weighted CN 0.30 98.94
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 1.00
Total Runoff (in) ------------------------------------------ 0.88
Peak Runoff (cfs)---------------------------------------- 0.61
Weighted Curve Number ............................ 98.94
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 3
2.4
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
'E 1.1
0 1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.7
0.65
0.6
0.55
0.5
0.45
N 0.4
w 0.35
0
0
0
1h 0.3
0.26
0.2
0.15
0.1
0.05
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 4
Input Data
Area(ac)----------------------------------------------------- 0.20
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 77.22
Rain Gage ID ---------------------------------------------- NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.20 - 77.22
Composite Area & Weighted CN 0.20 77.22
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 1.00
Total Runoff (in) ------------------------------------------ 0.05
Peak Runoff (cfs)---------------------------------------- 0.01
Weighted Curve Number ............................ 77.22
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 4
2.4
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
'E 1.1
0 1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.01
0.009
0.009
0.008
0.008
0.007
0.007
0.006
,E0.006
�0.005
0.004
0.004
0.004
0.003
0.003
0.002
0.002
0.001
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 5
Input Data
Area(ac)----------------------------------------------------- 0.95
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 85.08
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.95 - 85.08
Composite Area & Weighted CN 0.95 85.08
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 1.00
Total Runoff (in) ------------------------------------------ 0.17
Peak Runoff (cfs)---------------------------------------- 0.28
Weighted Curve Number ............................ 85.08
Time of Concentration (days hh:mm:ss) ..... 0 00:10:00

Subbasin : {POST-CON}.POST-CON : 5
2.4
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
'E 1.1
0 1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.28
027
0.26
0.25
0.24
0.23
0.22
0.21
0.2
0.19
0.18
_ 0.17
0.16
0 15
0 0.14
0.13
0.12
0.11
0.1
0.09
0.08
0.07
006
0.05
0.04
0.03
0.02
0.01
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 6
Input Data
Area(ac)----------------------------------------------------- 1.48
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 80.47
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
1.48 - 80.47
Composite Area & Weighted CN 1.48 80.47
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 1.00
Total Runoff (in) ------------------------------------------ 0.09
Peak Runoff (cfs)---------------------------------------- 0.18
Weighted Curve Number ............................ 80.47
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 6
2.4
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
'E 1.1
0 1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.2
0.19
0.18
0.17
0.16
0.15
0.14
0.13
0.12
0.11
w 0.1
0
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Junction Input
SN Element
Invert Ground/Rim Ground/Rim
Initial Initial Surcharge Surcharge Ponded Minimum
ID
Elevation
(Max)
(Max)
Water Water
Elevation
Depth
Area
Pipe
Elevation
Offset
Elevation Depth
Cover
(ft)
(ft)
(ft)
(ft) (ft)
(ft)
(ft)
(ft)
(in)
1 SCM-RISER
1028.75
1036.00
725
1028.75 0.00
0.00
-1036.00
0.00
0.00
2 SITE -JUNCTION -VIRTUAL
1028.50
1036.00
7.50
1028.50 0.00
0.00
-1036.00
0.00
0.00

Junction Results
SN Element
Peak
Peak Max HGL Max HGL
Max
Min Average HGL Average HGL
Time of
Time of Total Total Time
ID
Inflow
Lateral
Elevation
Depth Surcharge Freeboard
Elevation
Depth
Max HGL
Peak Flooded
Flooded
Inflow
Attained
Attained
Depth
Attained
Attained
Attained
Occurrence
Flooding Volume
Attained
Occurrence
(cfs)
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft) (days hh:mm) (days hh:mm) (ac-in)
(min)
1 SCM-RISER
0.03
0.00
1028.81
0.06
0.00
7.19
1028.78
0.03
0 06:01
0 00:00 0.00
0.00
2 SITE -JUNCTION -VIRTUAL
0.49
0.46
1028.59
0.09
0.00
7.41
1028.53
0.03
0 03:11
0 00:00 0.00
0.00

Pipe Input
SN Element
Length
Inlet Inlet
Outlet Outlet Total Average Pipe
Pipe Pipe
Manning's Entrance Exit/Bend Additional Initial
ID
Invert Invert
Invert Invert Drop Slope Shape
Diameteror Width
Roughness Losses
Losses Losses Flow
Elevation Offset
Elevation Offset
Height
(ft)
(ft) (ft)
(ft) (ft) (ft) ( % )
(in) (in)
(cfs)
1 SCM-BARREL
45.00
1028.75 0.00
1028.50 0.00 025 0.5600 CIRCULAR
18.000 18.000
0.0120 0.5000
0.5000 0.0000 0.00
2 SITE -LINK -VIRTUAL
2000.
1028.50 0.00
1022.00 0.00 6.50 32.5000 CIRCULAR
18.000 18.000
0.0120 0.5000
0.5000 0.0000 0.00

Flap No. of
Gate Barrels
No 1
No 1

Pipe Results
SN Element
Peak
Time of Design Flow
Peak Flow/ Peak Flow Travel Peak Flow
Peak Flow
Total Time Froude Reported
ID
Flow
Peak Flow
Capacity
Design Flow
Velocity Time
Depth
Depth/
Surcharged Number Condition
Occurrence
Ratio
Total Depth
Ratio
(cfs) (days hh:mm)
(cfs)
(ft/sec) (min)
(ft)
(min)
1 SCM-BARREL
0.03
0 06:02
8.48
0.00
2.95 025
0.06
0.04
0.00 Calculated
2 SITE -LINK -VIRTUAL
0.49
0 03:11
64.87
0.01
10.79 0.03
0.09
0.06
0.00 Calculated

Storage Nodes
Storage Node : SAND -FILTER
Input Data
Invert Elevation (ft)----------------------------------------------------------------------------------
1032-00
Max (Rim) Elevation (ft)--------------------------------------------------------------------------
1036-00
Max (Rim) Offset (ft)-------------------------------------------------------------------------------
4-00
Initial Water Elevation (ft)------------------------------------------------------------------------
1032-00
Initial Water Depth (ft)-----------------------------------------------------------------------------
0-00
Ponded Area (ftt)-------------------------------------------------------------------------------------
0-00
Evaporation Loss------------------------------------------------------------------------------------
0-00
Storage Area Volume Curves
Storage Curve: SAND -FILTER
Stage
Storage
Storage
Area
Volume
(ft)
(ft2)
(ft')
0
1776
0-000
1
2432
2104-00
2
3151
4895-50
3
3960
8451-00
4
4850
12856-00

Storage Area Volume Curves
Storage Volume (ft)
0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 81000 9.000 -10,000 11,000 12,000
d------------------------------------------------------------------------------- --- -
3.8 ---- -----
3.7 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
3.6 --- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----- -----
3.4-------- ------------------------ ------
3.3- - - - - ---- - - - ---- - - - ---- - - - ---- - - - ---- - - - ---- - - - -- -- - - - --- - - - - -- ------
3.2 --- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
3.1 ---- ---- ---- ---- ---- ---- -- - ---- ---- -----
?.9---------------------------------------------------------- - - - - -- -- --------------------------------
t.6 -------- ________ _______ _______ _______ _______ _____ ___ _ _______ _______ _______ _______ ______
d.3- - -- - ---- - - - --- -- - -- -- - - ---- ---- -- --- - -- -- - -- - -- -- --------------------------------------
----------------------
?.1 - - - - -- - - - - -- - - - - -- - - -- - - - -- - - - - -- - - - - -- - - - - -- - - - - --- - - - - -- - - - - - -
2- ------------------------------ ------ -- ------------------------------------ ------ ------
1.9----------------L -------L ------- L --- -- L -- --- I ------- I ------- I -------L -------L -------L ------- ------
1.7----------------------------- ---------------------------------------- ------------------
1.6 ---------- -------------
1.4 --- ---- ---- - ---- ---- ---- ---- ---- ---- ---- ---- -----
1.3 --- ---- -- ---- ---- ---- ---- ---- ---- ---- ---- -----
1.1- - - - - ---- - - - - -- -- - - - - ---- - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - -- ----------------------
1 - - - - -- ------
1.9- -- - - --- -- - --- ------
1.$ ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
1.7 - - -- - --- - --- -- -- -- -- - - -- - --- - --- -- -- -- -- -----
1.6 -- -- - -- -- - - --- ----- --- --- -- - - --- -- - --- -- - -- -- --------------------------------------
1.5 - - - - -- - - - - -- - - - - -- - - - - -- - - - - --- - - - - --
1.4- - - - - ---- - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - -- ------
1.3 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
1.2 - - -- - - -- - --- - --- -- -- -- -- - - -- - --- - --- -- -- -- -- - - ---
0
1,800 2,000 2,200 2,400 2,600 2,800 3,000 3,200 3,400 3,600 3,800 4,000 4,200 4,400 4,600 4,800
Storage Area (fin
- Storage Area - Storage Volu m e
d
M
If
3.1
3.5
3.6
3.4
3.3
3.3
3.1
3
2A
2A
2.3
2.s
2.1
2.4
1A
1.8
1.1
1.(
1.6
1.4
1.3
1.2
1.1
1
0.9
0.8
0.3
0.G
0.3
0.4
0.3
0.2
0.1
0
w
a�
m
fJ'1

Storage Node : SAND -FILTER (continued)
Outflow Weirs
SN Element
Weir
Flap
Crest
Crest
Length
Weir Total Discharge
ID
Type
Gate
Elevation
Offset
Height Coefficient
(ft)
(ft)
(ft)
(ft)
1 EM-SPILLWAY
Trapezoidal No
1035-00
3-00
10-00
1-00 3-33
Outflow Orifices
SN Element
Orifice
Orifice
Flap
Circular Rectangular Rectangular Orifice Orifice
ID
Type
Shape
Gate
Orifice
Orifice
Orifice Invert Coefficient
Diameter
Height
Width Elevation
(in)
(in)
(in) (ft)
1 PRINCIPAL -SPILLWAY Bottom
Rectangular No
36-00
36-00 1033-00 0-63
Output Summary Results
Peak Inflow (cfs)--------------------------------------------------------------------------------------
1-51
Peak Lateral Inflow (cfs)--------------------------------------------------------------------------
1-51
Peak Outflow (cfs)-----------------------------------------------------------------------------------
0-03
Peak Exfiltration Flow Rate (cfm)------------------------------------------------------------
0-00
Max HGL Elevation Attained (ft)--------------------------------------------------------------
1032-93
Max HGL Depth Attained (ft)-------------------------------------------------------------------
0-93
Average HGL Elevation Attained (ft)-------------------------------------------------------
103228
Average HGL Depth Attained (ft)------------------------------------------------------------
028
Time of Max HGL Occurrence (days hh:mm)-----------------------------------------
0 06-01
Total Exfiltration Volume (1000-ft3)---------------------------------------------------------
0-000
Total Flooded Volume (ac-in) -
0
Total Time Flooded (min)
0
Total Retention Time (sec)----------------------------------------------------------------------
0-00

Post -construction 10 Year, 24 Hour
BREC, P.A. Dollar General — Store #21867 13

Project Description
File Name ----------------------------------------------------
POST-CON-ROUTING.SPF
Description --------------------------------------------------
R:\Shared
Folders\PROJECTS\BREC\PROJ ECTS\316_TERAMORE_DEVELOPM ENT\3160622019_DOLLAR_GEN ERAL_N E WTO
Project Options
Flow Units ---------------------------------------------------
CFS
Elevation Type
Elevation
Hydrology Method .
SCS TR-55
Time of Concentration (TOC) Method --------
User -Defined
Link Routing Method
Kinematic Wave
Enable Overflow Ponding at Nodes ------------
YES
Skip Steady State Analysis Time Periods ---
NO
Analysis Options
Start Analysis On .
Jan 28, 2020
00-00-00
End Analysis On .
Jan 30, 2020
00:00:00
Start Reporting On .
Jan 28, 2020
00:00:00
Antecedent Dry Days
0
days
Runoff (Dry Weather) Time Step ----------------
0 01:00:00
days hh:mm:ss
Runoff (Wet Weather) Time Step ---------------
0 00:05:00
days hh:mm:ss
Reporting Time Step -----------------------------------
0 00:00:15
days hh:mm:ss
Routing Time Step ......................................
15
seconds
Number of Elements
Qty
Rain Gages
1
Subbasins
6
Nodes
4
Junctions
2
Outfalls
1
Flow Diversions
0
Inlets
0
Storage Nodes
1
Links
5
Channels
0
Pipes
2
Pumps
0
Orifices
1
Weirs
1
Outlets
1
Pollutants
0
Land Uses
0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
1 NEWTON Time Series 10YR-24HR Cumulative inches North Carolina Catawba 10 521 SCS Type II 24-hr

Subbasin Summary
SN Subbasin Area Peak Rate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac)
(in)
(in)
(ac-in)
(cfs)
(days hh:mm:ss)
1 {POST-CON}.POST-CON
: 1 021
484.00
98.00
521
4.97
1.02
1.40
0 00-05-00
2 {POST-CON}.POST-CON
: 2 028
484.00
79.60
521
3.04
0.86
1.36
0 00-05-00
3 {POST-CON}.POST-CON
: 3 0.30
484.00
93.50
521
4.46
1.33
1.97
0 00-05-00
4 {POST-CON}.POST-CON
: 4 020
484.00
39.00
521
024
0.05
0.02
0 00-05-00
5 {POST-CON}.POST-CON
: 5 0.95
484.00
4720
521
0.62
0.59
0.58
0 00-10-00
6 {POST-CON}.POST-CON
: 6 1.48
484.00
41.60
521
0.35
0.52
0.41
0 00-05-00

Node Summary
SN Element
Element
Invert Ground/Rim
Initial Surcharge Ponded Peak Max HGL
Max
Min
Time of
ID
Type
Elevation
(Max)
Water
Elevation
Area Inflow
Elevation Surcharge Freeboard
Peak
Elevation
Elevation
Attained
Depth
Attained
Flooding
Attained
Occurrence
(ft)
(ft)
(ft)
(ft)
(ft') (cfs)
(ft)
(ft)
(ft) (days hh:mm)
1 SCM-RISER
Junction
1028.75
1036.00
1028.75
0.00
0.00 4.55
1029.53
0.00
6.47
0 00:00
2 SITE -JUNCTION -VIRTUAL
Junction
1028.50
1036.00
1028.50
0.00
0.00 4.97
102928
0.00
6.72
0 00:00
3 OUTFALL
Outfall
1022.00
4.97
102228
4 SAND -FILTER
Storage Node
1032.00
1036.00
1032.00
0.00 4.72
103323

Link Summary
SN Element
Element From
To (Outlet)
Length
Inlet
Outlet Average Diameter or
Manning's Peak Design Flow
Peak Flow/ Peak Flow Peak Flow
Peak Flow
Total Time Reported
ID
Type
(Inlet)
Node
Invert
Invert Slope
Height
Roughness Flow
Capacity
Design Flow
Velocity
Depth
Depth/
Surcharged Condition
Node
Elevation
Elevation
Ratio
Total Depth
Ratio
(ft)
(ft)
(ft) ( % )
(in)
(cfs)
(cfs)
(ft/sec)
(ft)
(min)
1 SCM-BARREL
Pipe
SCM-RISER
SITE -JUNCTION -VIRTUAL
45.00
1028.75
1028.50 0.5600
18.000
0.0120 4.55
8.48
0.54
4.88
0.78
0.52
0.00 Calculated
2 SITE -LINK -VIRTUAL
Pipe
SITE-JUNCTION-VIRTUALOUTFALL
2000.
1028.50
1022.00 32.5000
18.000
0.0120 4.97
64.87
0.08
21.74
0.28
0.19
0.00 Calculated
3 PRINCIPAL -SPILLWAY Orifice
SAND -FILTER
SCM-RISER
1032.00
1028.75
36.000
4.52
4 SAND -MEDIA
Outlet
SAND -FILTER
SCM-RISER
1032.00
1028.75
0.03
5 EM-SPILLWAY
Weir
SAND -FILTER
SITE -JUNCTION -VIRTUAL
1032.00
1028.50
0.00

Subbasin Hydrology
Subbasin : {POST-CON}.POST-CON : 1
Input Data
Area(ac)----------------------------------------------------- 021
Peak Rate Factor ---------------------------------------- 484-00
Weighted Curve Number---------------------------- 98-00
Rain Gage ID NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
021 - 98-00
Composite Area & Weighted CN 021 98-00
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 521
Total Runoff (in) ------------------------------------------ 4-97
Peak Runoff (cfs)---------------------------------------- 1-40
Weighted Curve Number---------------------------- 98-00
Time of Concentration (days hh:mm:ss) ----- 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 1
7.5
7
6.5
6
5.5
5
4.5
4
3.5
3
2.5
2
1.5
05
1.45
1.4
1 35
1.3
1.25
1.2
1.15
1.1
1 05
0.95
09
_ 0.85
0.8
0.75
0 0.7
0.65
0
06
0.55
0.5
0 45
0.4
0.35
0.3
0.25
0.2
0 15
0.1
0.05
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 2
Input Data
Area(ac)----------------------------------------------------- 0.28
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 79.60
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.28 - 79.60
Composite Area & Weighted CN 0.28 79.60
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 5.21
Total Runoff (in) ------------------------------------------ 3.04
Peak Runoff (cfs)---------------------------------------- 1.36
Weighted Curve Number ............................ 79.60
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 2
8
7.5
7
6.5
6
55
5
4.5
4
3.5
3
2.5
2
1.5
0.6
1.45
1.4
1 35
1.3
1.25
1.2
1.15
1.1
1 05
0.95
09
_ 0.85
0.8
0.75
0 0.7
0.65
0
06
0.55
0.5
0 45
0.4
0.35
0.3
0.25
0.2
0 15
0.1
0.05
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 3
Input Data
Area(ac)----------------------------------------------------- 0.30
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 93.50
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.30 - 93.50
Composite Area & Weighted CN 0.30 93.50
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 5.21
Total Runoff (in) ------------------------------------------ 4.46
Peak Runoff (cfs)---------------------------------------- 1.97
Weighted Curve Number ............................ 93.50
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 3
8
7.5
7
6.5
6
55
5
4.5
4
3.5
3
2.5
2
1.5
0.6
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
1.3
N 1.2
1.1
0 1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 4
Input Data
Area(ac)----------------------------------------------------- 0.20
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 39.00
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.20 - 39.00
Composite Area & Weighted CN 0.20 39.00
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 5.21
Total Runoff (in) ------------------------------------------ 0.24
Peak Runoff (cfs)---------------------------------------- 0.02
Weighted Curve Number ............................ 39.00
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 4
8
7.5
7
6.5
6
55
5
4.5
4
m 3.5
0'_
3
2.5
2
1.5
0.6
0.019
0.018
0.017
0.016
0.015
0.014
0.013
0.012
F 0.011
w 0.01
0
0
F=0.009
0.008
0.007
0.006
0.005
0.004
0.003
0.002
0.001
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 5
Input Data
Area(ac)----------------------------------------------------- 0.95
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 47.20
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
0.95 - 47.20
Composite Area & Weighted CN 0.95 47.20
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 5.21
Total Runoff (in) ------------------------------------------ 0.62
Peak Runoff (cfs)---------------------------------------- 0.58
Weighted Curve Number ............................ 47.20
Time of Concentration (days hh:mm:ss) ..... 0 00:10:00

Subbasin : {POST-CON}.POST-CON : 5
8
7.5
7
6.5
6
55
5
4.5
4
m 3.5
0'_
3
2.5
2
1.5
0.5
0.62
0.6
0.58
0.56
0.54
0.52
0.5
0.48
0.46
0.44
0.42
0.4
0.30
0.36
0.34
032
0 0.3
0.28
1h 0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Subbasin : {POST-CON}.POST-CON : 6
Input Data
Area(ac)----------------------------------------------------- 1.48
Peak Rate Factor ---------------------------------------- 484.00
Weighted Curve Number ---------------------------- 41.60
Rain Gage ID ............................................... NEWTON
Composite Curve Number
Area Soil Curve
Soil/Surface Description (acres) Group Number
1.48 - 41.60
Composite Area & Weighted CN 1.48 41.60
Subbasin Runoff Results
Total Rainfall (in) ----------------------------------------- 5.21
Total Runoff (in) ------------------------------------------ 0.35
Peak Runoff (cfs)---------------------------------------- 0.41
Weighted Curve Number ............................ 41.60
Time of Concentration (days hh:mm:ss) ..... 0 00:05:00

Subbasin : {POST-CON}.POST-CON : 6
8
7.5
7
6.5
6
55
5
4.5
4
3.5
3
2.5
2
1.5
0.5
0.44
0.42
0.4
0.38
0.36
0.34
0.32
0.3
0.28
0.26
0.24
w 0.22
0
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
Rainfall Intensity Graph
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 (hrs)
Runoff Hydrograph
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 (hrs)

Junction Input
SN Element
Invert Ground/Rim Ground/Rim
Initial Initial Surcharge Surcharge Ponded Minimum
ID
Elevation
(Max)
(Max)
Water Water
Elevation
Depth
Area
Pipe
Elevation
Offset
Elevation Depth
Cover
(ft)
(ft)
(ft)
(ft) (ft)
(ft)
(ft)
(ft)
(in)
1 SCM-RISER
1028.75
1036.00
725
1028.75 0.00
0.00
-1036.00
0.00
0.00
2 SITE -JUNCTION -VIRTUAL
1028.50
1036.00
7.50
1028.50 0.00
0.00
-1036.00
0.00
0.00

Junction Results
SN Element
Peak
Peak Max HGL Max HGL
Max
Min Average HGL Average HGL
Time of
Time of Total Total Time
ID
Inflow
Lateral
Elevation
Depth Surcharge Freeboard
Elevation
Depth
Max HGL
Peak Flooded
Flooded
Inflow
Attained
Attained
Depth
Attained
Attained
Attained
Occurrence
Flooding Volume
Attained
Occurrence
(cfs)
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft) (days hh:mm) (days hh:mm) (ac-in)
(min)
1 SCM-RISER
4.55
0.00
1029.53
0.78
0.00
6.47
1028.82
0.07
0 11:56
0 00:00 0.00
0.00
2 SITE -JUNCTION -VIRTUAL
4.97
0.97
102928
0.78
0.00
6.72
1028.57
0.07
0 11:57
0 00:00 0.00
0.00

Pipe Input
SN Element
Length
Inlet Inlet
Outlet Outlet Total Average Pipe
Pipe Pipe
Manning's Entrance Exit/Bend Additional Initial
ID
Invert Invert
Invert Invert Drop Slope Shape
Diameteror Width
Roughness Losses
Losses Losses Flow
Elevation Offset
Elevation Offset
Height
(ft)
(ft) (ft)
(ft) (ft) (ft) ( % )
(in) (in)
(cfs)
1 SCM-BARREL
45.00
1028.75 0.00
1028.50 0.00 025 0.5600 CIRCULAR
18.000 18.000
0.0120 0.5000
0.5000 0.0000 0.00
2 SITE -LINK -VIRTUAL
2000.
1028.50 0.00
1022.00 0.00 6.50 32.5000 CIRCULAR
18.000 18.000
0.0120 0.5000
0.5000 0.0000 0.00

Flap No. of
Gate Barrels
No 1
No 1

Pipe Results
SN Element
Peak
Time of Design Flow
Peak Flow/ Peak Flow Travel Peak Flow
Peak Flow
Total Time Froude Reported
ID
Flow
Peak Flow
Capacity
Design Flow
Velocity Time
Depth
Depth/
Surcharged Number Condition
Occurrence
Ratio
Total Depth
Ratio
(cfs) (days hh:mm)
(cfs)
(ft/sec) (min)
(ft)
(min)
1 SCM-BARREL
4.55
0 11:57
8.48
0.54
4.88 0.15
0.78
0.52
0.00 Calculated
2 SITE -LINK -VIRTUAL
4.97
0 11:57
64.87
0.08
21.74 0.02
028
0.19
0.00 Calculated

Storage Nodes
Storage Node : SAND -FILTER
Input Data
Invert Elevation (ft)----------------------------------------------------------------------------------
1032-00
Max (Rim) Elevation (ft)--------------------------------------------------------------------------
1036-00
Max (Rim) Offset (ft)-------------------------------------------------------------------------------
4-00
Initial Water Elevation (ft)------------------------------------------------------------------------
1032-00
Initial Water Depth (ft)-----------------------------------------------------------------------------
0-00
Ponded Area (ftt)-------------------------------------------------------------------------------------
0-00
Evaporation Loss------------------------------------------------------------------------------------
0-00
Storage Area Volume Curves
Storage Curve: SAND -FILTER
Stage
Storage
Storage
Area
Volume
(ft)
(ft2)
(ft')
0
1776
0-000
1
2432
2104-00
2
3151
4895-50
3
3960
8451-00
4
4850
12856-00

Storage Area Volume Curves
Storage Volume (ft)
0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 81000 9.000 -10,000 11,000 12,000
d------------------------------------------------------------------------------- --- -
3.8 ---- -----
3.7 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
3.6 --- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----- -----
3.4-------- ------------------------ ------
3.3- - - - - ---- - - - ---- - - - ---- - - - ---- - - - ---- - - - ---- - - - -- -- - - - --- - - - - -- ------
3.2 --- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
3.1 ---- ---- ---- ---- ---- ---- -- - ---- ---- -----
?.9---------------------------------------------------------- - - - - -- -- --------------------------------
t.6 -------- ________ _______ _______ _______ _______ _____ ___ _ _______ _______ _______ _______ ______
d.3- - -- - ---- - - - --- -- - -- -- - - ---- ---- -- --- - -- -- - -- - -- -- --------------------------------------
----------------------
?.1 - - - - -- - - - - -- - - - - -- - - -- - - - -- - - - - -- - - - - -- - - - - -- - - - - --- - - - - -- - - - - - -
2- ------------------------------ ------ -- ------------------------------------ ------ ------
1.9----------------L -------L ------- L --- -- L -- --- I ------- I ------- I -------L -------L -------L ------- ------
1.7----------------------------- ---------------------------------------- ------------------
1.6 ---------- -------------
1.4 --- ---- ---- - ---- ---- ---- ---- ---- ---- ---- ---- -----
1.3 --- ---- -- ---- ---- ---- ---- ---- ---- ---- ---- -----
1.1- - - - - ---- - - - - -- -- - - - - ---- - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - -- ----------------------
1 - - - - -- ------
1.9- -- - - --- -- - --- ------
1.$ ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
1.7 - - -- - --- - --- -- -- -- -- - - -- - --- - --- -- -- -- -- -----
1.6 -- -- - -- -- - - --- ----- --- --- -- - - --- -- - --- -- - -- -- --------------------------------------
1.5 - - - - -- - - - - -- - - - - -- - - - - -- - - - - --- - - - - --
1.4- - - - - ---- - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - --- - - - - -- ------
1.3 ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- -----
1.2 - - -- - - -- - --- - --- -- -- -- -- - - -- - --- - --- -- -- -- -- - - ---
0
1,800 2,000 2,200 2,400 2,600 2,800 3,000 3,200 3,400 3,600 3,800 4,000 4,200 4,400 4,600 4,800
Storage Area (fin
- Storage Area - Storage Volu m e
d
M
If
3.1
3.5
3.6
3.4
3.3
3.3
3.1
3
2A
2A
2.3
2.s
2.1
2.4
1A
1.8
1.1
1.(
1.6
1.4
1.3
1.2
1.1
1
0.9
0.8
0.3
0.G
0.3
0.4
0.3
0.2
0.1
0
w
a�
m
fJ'1

Storage Node : SAND -FILTER (continued)
Outflow Weirs
SN Element
Weir
Flap
Crest
Crest
Length
Weir Total Discharge
ID
Type
Gate
Elevation
Offset
Height Coefficient
(ft)
(ft)
(ft)
(ft)
1 EM-SPILLWAY
Trapezoidal No
1035-00
3-00
10-00
1-00 3-33
Outflow Orifices
SN Element
Orifice
Orifice
Flap
Circular Rectangular Rectangular Orifice Orifice
ID
Type
Shape
Gate
Orifice
Orifice
Orifice Invert Coefficient
Diameter
Height
Width Elevation
(in)
(in)
(in) (ft)
1 PRINCIPAL -SPILLWAY Bottom
Rectangular No
36-00
36-00 1033-00 0-63
Output Summary Results
Peak Inflow (cfs)--------------------------------------------------------------------------------------
4-72
Peak Lateral Inflow (cfs)--------------------------------------------------------------------------
4-72
Peak Outflow (cfs)-----------------------------------------------------------------------------------
4-55
Peak Exfiltration Flow Rate (cfm)------------------------------------------------------------
0-00
Max HGL Elevation Attained (ft)--------------------------------------------------------------
103323
Max HGL Depth Attained (ft)-------------------------------------------------------------------
123
Average HGL Elevation Attained (ft)-------------------------------------------------------
1032-55
Average HGL Depth Attained (ft)------------------------------------------------------------
0-55
Time of Max HGL Occurrence (days hh:mm)-----------------------------------------
0 11-56
Total Exfiltration Volume (1000-ft3)---------------------------------------------------------
0-000
Total Flooded Volume (ac-in) -
0
Total Time Flooded (min)
0
Total Retention Time (sec)----------------------------------------------------------------------
0-00