SW6210207_SW Narrative_20210301

3D Community Church
Harnett County, NC
Storm Water Narrative
2/16/21
The objective of this project is to build a church with associated parking area and utilize
the existing terrain's flat topography and high infiltration rates of the soil to treat the storm
water runoff from the project.
Storm water runoff from the building and parking areas will be conveyed to grassed
swales. The lower sections of the grassed swales have been designed with near 0% grade in
order to slow the release of the storm water runoff and allow it to infiltrate as much as possible
into the existing sandy soils.
The swales have been designed to non-erosively pass the 10-year storm event. Any
storms exceeding the design capacity of the swale will overtop the swale with dispersed flow to
downstream wooded areas. All swales have been designed with 3:1 side slopes, 2' bottom
widths, and a minimum of 1.3' depth. The swales will be vegetated and matted to reduce the
likelihood of erosion.
ZHILL�Zb R
ENGINEERING, PLLC
749 Walker Road, Sanford, NC 27332 = ,
i -
PO Box 249, Sanford, NC 27331 �� S' -
Phone: [phone]
e-mail- jhilliard@hilliardengineering. com
NC License #- P-0836
2116121