NC Central University P3 - Chidley South - Chidley NCDEQ Stormwater Supplement Form

DRAINAGE AREAS
1 Is this a high density project?Yes
2 If so, number of drainage areas/SCMs 5
3
Is all/part of this project subject to previous rule
versions?No
FORMS LOADED
Entire Site 1 2 3 4 5
4 Type of SCM Sand Filter
5 Total BUA in project (sq ft)152874 sf 57238 sf 34639 sf 28616 sf 28257 sf 4124 sf
6
New BUA on subdivided lots (subject to
permitting) (sq ft)
7
New BUA outside of subdivided lots (subject to
permitting) (sf)55176 sf 2683 sf 23300 sf 24270 sf 1972 sf 2951 sf
8 Offsite - total area (sq ft)117856 sf 69336 sf 6943 sf 5845 sf 35732 sf
9 Offsite BUA (sq ft)71594 sf 44468 sf 5129 sf 3394 sf 18603 sf
10 Breakdown of new BUA outside subdivided lots:
- Parking (sq ft)4971 sf 4861 sf
- Sidewalk (sq ft)26969 sf 796 sf 3785 sf 10385 sf 1972 sf 2951 sf
- Roof (sq ft)28234 sf 14654 sf 13580 sf
- Roadway (sq ft)
- Future (sq ft)

- Other, please specify in the comment box
below (sq ft) 2192 sf 1887 sf 305 sf
11
New infiltrating permeable pavement on
subdivided lots (sq ft)
12
New infiltrating permeable pavement outside of
subdivided lots (sq ft)
13
Exisitng BUA that will remain (not subject to
permitting) (sq ft)18914 sf 9638 sf 6211 sf 1742 sf 7682 sf 1173 sf
14 Existing BUA that is already permitted (sq ft)
15 Existing BUA that will be removed (sq ft)33063 sf 1070 sf 2957 sf 21990 sf 7911 sf
16 Percent BUA 53%63%87%40%55%30%
17 Design storm (inches)1 in 1 in
18 Design volume of SCM (cu ft)2400 cf 2400 cf
19 Calculation method for design volume Simple Method
20
DRAINAGE AREA INFORMATION
ADDITIONAL INFORMATION
The drainage areas 1, 2, 3, 4, and 5 correspond to the full size proposed
drainage area maps with drainage areas 1, 2A, 2B, 3, and Analysis Point B,
respectively. Other BUA includes mechanical yard and retaining walls.
Please use this space to provide any additional information about the
drainage area(s):
SAND FILTER
1 Drainage area number 2
2 Design volume of SCM (cu ft)2400 sf
3 Is the SCM sized to treat the SW from all surfaces at build-out?Yes
4 Is the SCM located away from contaminated soils?Yes
5 What are the side slopes of the SCM (H:V)?:1
6
Does the SCM have retaining walls, gabion walls or other engineered
side slopes? No
7
Are the inlets, outlets, and receiving stream protected from erosion (10-
year storm)?Yes
8
Is there an overflow or bypass for inflow volume in excess of the
design volume?Yes
9 What is the method for dewatering the SCM for maintenance?Pump (preferred)
10 If applicable, will the SCM be cleaned out after construction?Yes
11 Does the maintenance access comply with General MDC (8)?Yes
12 Does the drainage easement comply with General MDC (9)?Yes
13
If the SCM is on a single family lot, does (will?) the plat comply with
General MDC (10)?No
14 Is there an O&M Agreement that complies with General MDC (11)? Yes
15 Is there an O&M Plan that complies with General MDC (12)?Yes
16 Does the SCM follow the device specific MDC?Yes
17 Was the SCM designed by an NC licensed professional?Yes
18 SHWT elevation (fmsl)348.2
19 Type of sand filter (open or closed)Closed
20 If closed, will the filter will be pre-cast or pour-in-place?Pre Cast
21 If closed, top of grate elevation (fmsl)357.5
22 Is this sand filter designed to attenuate peak flows? No
23 Volume that can be retained in the sediment chamber (cubic feet)6360 cf
24 Will there be a permanent pool in the sediment chamber?Yes
25 Bottom of the sediment chamber (fmsl)344.20
26 Area of the sediment chamber (square feet)1200 sf
27 Physical depth of the sediment chamber (inches)96 in
28
Ponding depth in the sediment chamber, above any permanent pool
(inches)12 in
29 Elevation of top of weir between chambers (fmsl)346.9
30 Volume that can be retained in the sand chamber (cubic feet)6360 cf
31 Bottom of the sand chamber (fmsl)344.20
32 Area of the sand chamber (square feet)1200 sf
33 Physical depth of the sand chamber (inches)96 in
34
Ponding depth in the sand chamber, above any permanent pool
(inches)10 in
35 Elevation of the bypass device (fmsl)347.7
36 Type of bypass device 6" DIP
37 Mechanism for distributing flow over the sand surface Weir
38 Sand specification for sand chamber ASTM C-33
39 Depth above underdrain pipe (inches)30 in
40
Will the media be maintained to drain at least two inches per hour at
the sand surface?Yes
41
Is at least one clean-out pipe provided at the low point of each
underdrain line?Yes
42 Will clean-out pipes be capped? Yes
43
Please use this space to provide any additional information about the
Sand Filter(s):
SAND FILTER MDC FROM 02H .1056
GENERAL MDC FROM 02H .1050
Sand Chamber
Sediment Chamber
ADDITIONAL INFORMATION
Sand Filter 1 6:08 PM 3/4/2019