SW1190701_The Riveter - Low Density Sotemwater Narative_7/18/2019

The Riveter
Low Density Stormwater Management Plan
The Riveter is a proposed indoor / outdoor sports complex to be located in Henderson County, North
Carolina, near the intersection of Sierra Nevada Way, Ferncliff Park Drive and Old Fanning Bridge Road.
The existing site is a portion of a small farm previously containing a residential home, barns, small out
buildings and a gravel drive. The site has been and significant portions will continue to be utilized for
agricultural purposes. Available Soils Report data indicate the site soils consist of a Codorus Loam (58%)
and a Delanco Loam (42%). Both of these soils are of Hydrologic Group C.
The proposed building will have approximately 40,000 square feet under roof with a portion of the
building being an open-air structure. Parking and access roads into the site will be comprised of gravel
and asphalt, however for purposes of stormwater modeling, both gravel and pavement were considered
to be impervious. Other hardscapes will include a sidewalk and a small concrete area outside the main
entrance.
The site is approximately 16.67 acres in total area. The total built upon area will be approximately 2.09
acres (91,128 square feet). This will result in a built upon area of 12.55% of the total site. This meets the
requirements low density stormwater management in the French Broad River — Stream Class B
watershed.
The design of the site has been careful to avoid concentrating stormwater in the parking and ancillary
areas. Roof drainage will be dispersed into the mulched landscape areas adjacent to the building. The
sheet flow storm drainage will pass through a vegetated strip adjacent to the parking area prior to
reaching the 10+ acre agricultural use area. Stormwater must pass through this 10+ acre row crop area
and an additional natural vegetated buffer prior to reaching the French Broad River.