Swamps and Flooding
Throughout the Blackwater River watershed are numerous permanent swamp habitats that maintain inundation year round. These swampy wetlands act as sponges absorbing precipitation but also advancing floods. This retention capability is crucial to the resiliency of watersheds with wetland habitats. Wetland conservation can even replace the need for dredging and levee systems (EPA, n.d.). When the perimeter of the Blackwater River watershed was being mapped for this blog, there were several locations that were difficult to delineate due to proximity to a swamp that lie between the Black water River watershed and the Chesapeake Bay watershed via the James River. In addition to the retention of water during flood events, wetlands also have the ability to filter water through biotic processes associated with the aquatic plant and microbial life (EPA, 2002).
Human development is often at odds with the conditions of rain events. Paved surfaces, rooftops and wetland draining alter native hydrology resulting in flood conditions. Franklin, Va sits at the very southern end of the Blackwater River, close to its confluence with the Nottoway River. As the most developed site along the Blackwater River, Franklin is comparatively vulnerable to extreme weather. The City of Franklin has compiled a list of historic floods that include the following:
- August 1940, Weeks of heavy rain saturated Southeast Virginia raising the Blackwater River to 21.9 ft, 10ft over flood stage.
- September 1999, Hurricane Floyd hit the area weeks after a tropical storm, pouring upwards of a foot of rain. The flooding in Franklin was at least 4ft over the previous 1940 record. Hundreds of buildings were destroyed.
- September 2006, Tropical Storm Ernesto caused flooding up to 15ft+
- October 2006, A low pressure weather system dumped over 10 inches of rain, pushing the Blackwater River to 22ft. This flood caused nearly $5 million in damage as downtown Franklin was again underwater (City of Franklin, n.d.).
The following links will take the reader to the NOAA pages for the four flood gauges along the Blackwater River, including the one at the City of Franklin.
Dendron: https://water.noaa.gov/gauges/DNDV2
Zuni: https://water.noaa.gov/gauges/ZUNV2
Above Franklin: https://water.noaa.gov/gauges/FKNV2
Franklin: https://water.noaa.gov/gauges/FKLV2
Flood gauge at the City of Franklin, VA. (NOAA, n.d.)
Resources
City of Franklin. (n.d.) City of Franklin Historical Floods. City of Franklin. retrieved November 18, 2024. https://www.franklinva.com/media/161150/historical-floods.pdf
FEMA. (1999). Getty Images. [Photograph]. In Vitka, W. (2019). Photos: Looking back at Hurricane Floyd’s destruction, 20 years later. WTOP News. retrieved November 18, 2024. https://wtop.com/gallery/media-galleries/photos-looking-back-at-hurricane-floyds-destruction-20-years-later/
Helber, S. (1999).Associated Press. [Photograph]. In Vitka, W. (2019). Photos: Looking back at Hurricane Floyd’s destruction, 20 years later. WTOP News. retrieved November 18, 2024. https://wtop.com/gallery/media-galleries/photos-looking-back-at-hurricane-floyds-destruction-20-years-later/
National Oceanic and Atmospheric Administration. (n.d.) [Photograph]. retrieved November 18, 2024. https://water.noaa.gov/gauges/FKLV2
United States Environmental Protection Agency. (n.d.) Why are Wetlands Important?. United States Environmental Protection Agency. retrieved November 18, 2024. https://www.epa.gov/wetlands/why-are-wetlands-important
United States Environmental Protection Agency. (2002). Functions and Values of Wetlands. United States Environmental Protection Agency. retrieved November 18, 2024. https://www.epa.gov/sites/default/files/2021-01/documents/functions_values_of_wetlands.pdf