Establishing Volume Reduction Goals and Reducing Stormwater Runoff Using Low Impact Development to Improve Coastal Water Quality
Abstract
Despite the Clean Water Act (CWA), passed by Congress in 1972, coastal water quality
has continued to decline. The primary reason is the Act’s failure to adequately deal
with stormwater runoff, the leading source of water pollution in coastal areas. Coastal
development causes the velocity and volume of rainwater running off the land to increase,
picking up pollutants in the process. Traditional stormwater systems convey that runoff
directly into watersheds and coastal waters. Alternatives to the tradition stormwater
systems exist that prevent runoff, instead of conveying it off the land as fast as
possible. Low impact development (LID) is one option that uses a variety of techniques
to mimic the lands natural hydrology by holding rainwater on the land and allowing
it to infiltrate the soil. LID incorporate fairly simple measures, such as disconnecting
downspouts from impervious surfaces, using rain barrels to capture runoff, and installing
rain gardens, to reduce the runoff from development.
Reducing stormwater runoff can be an effective way to improve water quality in areas
where waters are not meeting their designated uses established under the CWA. This
can be done by bringing runoff levels back to historically acceptable volumes. This
analysis uses the methods in the NC Coastal Federation’s Watershed Restoration Planning
Guidebook to establish a stormwater runoff volume reduction goal by calculating the
increase in runoff between 2004 and 2013 in Beaufort, NC. The study demonstrates the
ease of setting reduction goals using the NCCF guidebook methods. It then presents
various LID techniques as a cost effective approach to meet the reduction target.
The results for the 9-year period show a 7% increase in stormwater runoff volumes.
The estimated increase in runoff volume was 423.876 acre-feet. The runoff rate went
from 54% to 61%. This correlates closely with the increase seen in impervious surfaces
in the study area. Impervious cover went from 29% in 2004, up to 37% in 2013, an 8%
increase.
Type
Master's projectPermalink
https://hdl.handle.net/10161/8544Citation
Fouts, Shannon (2014). Establishing Volume Reduction Goals and Reducing Stormwater Runoff Using Low Impact
Development to Improve Coastal Water Quality. Master's project, Duke University. Retrieved from https://hdl.handle.net/10161/8544.Collections
More Info
Show full item record
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
Rights for Collection: Nicholas School of the Environment
Works are deposited here by their authors, and represent their research and opinions, not that of Duke University. Some materials and descriptions may include offensive content. More info