SW4210704_Stormwater Narrative_20210803

Stormwater Treatment & Management Narrative
Dolcetto Subdivision
July, 2021
The Dolcetto subdivision is a single family subdivision located at the intersection
of West Center Street and Biesecker Road in Davidson County just north of
Lexington, NC. The site is located within the NPDES Phase II area. It is being
developed by New Ventures Land Development, LLC.
The subdivision is planned for 119 single family lots with approximately 4,710
linear feet of ribbon paved road. With a site area of 77.73 acres and a built -
upon area of 13.7%, the site is a low density development.
Construction of the new homes and roads will take place on the high ground
resulting in no impacts to stream or wetlands due to lot or road grading. A
single temporary stream impact will occur in Phase 2 for a sanitary sewer line tie-
in.
Vegetated roadside ditches are utilized along all roadways. A side slope of 3:1 is
utilized on each side of the ditches. Calculations are included that show no
erosion should occur during the 10-year storm event.
Riprap stormwater outlets have been engineered to prevent downslope erosion
at all discharge points while also creating dispersed flow. Discharges occur a
minimum of 150 feet from jurisdictional streams which allows flow through
vegetated buffer prior to reaching the streams.
Although this is a low density development and on -site detention is not required,
a dry -detention pond has been designed for the western portion of the site.
That portion of the site currently discharges to an existing NCDOT storm system.
Due to the increase in built -upon area and current undersized NCDOT pipe
system, we worked with NCDOT to develop a solution that will help prevent any
detrimental affects to downstream properties. With the use of the dry detention
pond, the post construction discharge is less than the pre construction discharge
for the 1, 2, 10, 25, and 50 year 24 hour storms.
All of the runoff for the site flows into Swearing Creek (12-113 Class Q.
An Erosion and Sedimentation Control Plan was approved for the site on May 22,
2020. The subsequent Certificate of Coverage was obtained on June 24, 2020.
Measures have been put in place to help prevent any off -site sedimentation
during the construction activities. A copy of this plan is also included in this
submittal. Sediment basins and other erosion control devises will remain in place
until site stabilization has occurred.

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Following the completion of construction by New Ventures, the lots will be sold
to a builder for home construction and common areas will be transferred to a
home owners association.