SW6220801_Stormwater Narrative_20220816

5245 Red Hill Church Rd
FLEET TEM PLE Coats, NC27521
ENGINEERING 910.658.2446
[e-mail]
P L LC Firm License P-2357
Shiloh
Upper Little River Township, Harnett County
06.27.2022
PROJECT NARRATIVE
Project & Site Description
The purpose of this project is to develop a 120.8 acre residential subdivision. The
property is existing farmland and woodland. Existing topography drains mainly to the
north at slopes of approximately 1% - 13% to Duncan's Creek and to an un-named
tributary Duncan's Creek. Wetlands have been delineated on site. No wetlands will be
disturbed during construction of the property The Site is limited to maximum 24%
impervious area upon build -out (Low Density Development).
Adjacent Property
The land uses in the surrounding areas are residential and agricultural.
Soils
The soils in this project consist of Bb (Bibb loam, frequently flooded), BnB (Blaney
loamy sand, 2 to 8% slopes), DoA (Dothan loamy sand, 0 to 2% slopes), FaB (Fuquay
loamysand, 0 to 6%slopes), LoF (Louisa fine sandy loam, 25 to 45%slopes), NeD (Nason
silt loam, 8 to 15% slopes), NoB (Norfolk loamy sand, 2 to 6% slopes), Wh (Wehadkee
loam, frequently flooded),
Bb is categorized as poorly drained, moderately permeable, and is poorly suited to
most urban and recreational uses. BnB is categorized as well drained, moderately
slowly permeable, and is moderately suited to most urban and recreational uses. DoA
is categorized as well drained, moderately to moderately slowly permeable, and is
moderately suited to most urban and recreational uses. FaB is categorized as well
drained, moderately permeable, and is moderately suited to most urban and
recreational uses. LoF is categorized as excessively drained, moderately rapid
permeable, and is poorly suited to most urban and recreational uses. NeD is
categorized aswell drained, moderately permeable, and is moderately suited to most
urban and recreational uses. NoB is categorized as well drained, moderately
permeable, and is well suited to most urban and recreational uses. Wh is categorized
as poorly drained, moderately permeable, and is poorly suited to most urban and
recreational uses.
Planned Stormwater Manaaement. Erosion and Sediment Control
As shown on the Erosion Control Plan the project will be controlled and stabilized with
diversion berms, silt fence, rock check dams, and temporary skimmer basins with
baffles. Diversion berms will be constructed from topsoil graded from the site and will
be backed with silt fence where needed. All measures will be constructed and
maintained to NCDEQ & Harnett Countystandards and requirements.

After erosion control measures are removed. Surface waters from the roadway areas
will drain via grassed roadside ditches to owner maintained grassy swales which will
convey the runoff from the property. Impervious areas on some portions of the lots
will surface drain through the grassed yard areas over the natural contours of the Site.
Project impervious percentage is limited to 24%. Proposed impervious limits as
fo I I ows:
IMPERVIOUS AREA CALCULATIONS:
TRACT AREA: 5,262,484 SF
IMPERVIOUS AREA ALLOWED: 24% MAX (LOW DENSITY)
5,262,484 SF X 0.24=1,262,996 SF MAXIMUM ALLOWABLE IMPERVIOUS
IMPERVIOUS AREA BY DESIGN
144,170 SF ASPHALT
1,068,000 SF(12,OOOSF/LOT X 89 LOTS)
1,212,170 SF TOTAL IMPERVIOUS BY DESIGN (23.0%)