SW6240101_Stormwater Narrative_20240115

5245 Red Hill Church Rd
_1 1-1 FLEET TEMPLE Coats, NC27521
ENGINEERING 910.658.2446
[e-mail]
PLLC Firm License P-2357
Freedom Acres
Upper Little River Township, Harnett County
11.22.2023
PROJECT NARRATIVE
Project & Site Description
The purpose of this project is to develop a 70.0 acre residential subdivision. The
property is existing farmland and woodland. Existing topography drains mainly to the
south and east at slopes of approximately 1% - 7% to Bear Branch and to Walker'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 Au (Augusta fine sandy loam, rarely flooded), Bb
(Bibb loam,frequently flooded), BnB (Blaney loamy sand,2 to 8%slopes), BnD (Blaney
loamy sand, 8 to 15% slopes), CeD (Cecil fine sandy loam, 8 to 15% slopes), GaB (Gilead
loamy sand, 2 to 8% slopes), NoA (Norfolk loamy sand, 0 to 2% slopes), NoB Norfolk
loamy sand, 2 to 6% slopes), and WaB (Wagram loamy sand, 0 to 6% slopes).
Au is categorized as somewhat poorly drained, moderately permeable, and is poorly
suited to most urban and recreational uses. 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. BnD is categorized as well drained, moderately
slowly permeable, and is poorly/moderately suited to most urban and recreational
uses. CeD is categorized as well drained, moderately permeable, and is moderately
suited to most urban and recreational uses. GaB is categorized as moderately well
drained, moderately slowly permeable, and is moderately suited to most urban and
recreational uses. NoA is categorized as well drained, moderately permeable, and is
well 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. WaB
is categorized as well drained, moderately permeable, and is well suited to most urban
and recreational uses.
Planned Stormwater Management, 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 County standards 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
follows:
IMPERVIOUS AREA CALCULATIONS:
WEST SIDE OF TIM CURRIN ROAD
TRACT AREA: 1,106,105 SF
SURFACE WATER AREA: 189,135 SF
TRACT AREA - SURFACE WATER AREA:916,970 SF
IMPERVIOUS AREA ALLOWED: 24% MAX (LOW DENSITY)
916,970 SF X 0.24=220,073 SF MAXIMUM ALLOWABLE IMPERVIOUS
IMPERVIOUS AREA BY DESIGN
59570 SF ASPHALT
160360 SF(8,440 SF/LOT X 19 LOTS)
219930 SF TOTAL IMPERVIOUS BY DESIGN (23.99%)
8,440 SF MAXIMUM IMPERVIOUS AREA PER LOT (INCLUDES AREA BETWEEN R/W
AND EDGE OF PAVEMENT)
EAST SIDE OF TIM CURRIN ROAD
TRACT AREA: 1,943,398 SF
SURFACE WATER AREA: 0 SF
TRACT AREA - SURFACE WATER AREA: 1,943,398 SF
IMPERVIOUS AREA ALLOWED: 24% MAX (LOW DENSITY)
1,943,398 SF X 0.24=466,416 SF MAXIMUM ALLOWABLE IMPERVIOUS
IMPERVIOUS AREA BY DESIGN
90,166 SF ASPHALT
375,760 SF(6,710 SF/LOT X56 LOTS)
465,926 SF TOTAL IMPERVIOUS BY DESIGN (23.9%)
6,710SF MAXIMUM IMPERVIOUS AREA PER LOT (INCLUDES AREA BETWEEN R/W
AND EDGE OF PAVEMENT)