Hooffs Run - Flooding
Hooffs Run Watershed - Flooding
Flooding is a topical issue for many residents living in the Hooffs Run watershed, particularly those in Del Ray neighborhood. The most recent Rain Event on September 10, 2020, resulted in 315 requests for service from local residents. While a USGS monitoring station within the Hooffs Run watershed could not be located, USGS 01653000 monitors the nearby Cameron Run, which displays a significant increase (discharge, cubic feet per second) on September 10, 2020.
The map below highlights a residential area that is reportedly subject to frequent flooding, which is also highlighted in the City of Alexandria ‘heat map’ of service calls from September 10, 2020.
Presumably the highlighted area is at, or near, sea level, and during rain events a significant amount of water flows down from the hilly area west of Russell Road overwhelming the storm water system. The flow of surface, and subsurface water, may follow the direction of the blue arrows.
East Monroe
Avenue (July 23, 2020) Source:
Alexandria Times.
East Monroe Avenue (September 10, 2020) Source: Alexandria Times.
The Alexandria Times is particularly critical of the city’s
approach to storm water management, and other policies they claim exacerbated
the effect of storms. A recent editorial
cited increased population density, favoring development over preservation of
wetlands and mature trees, and lack of urgency in overhauling the storm water
system.
For their part, the city has a number of planned projects to mitigate the impacts of flooding, which are outlined in some detail here. Of interest, in 2016 a City of Alexandria Storm Sewer Capacity Analysis (CASSCA) recommended more than US$40 in storm water sewer capacity investments in Hooffs Run (and four mile run).
However, it would seem that unless this project results in a significant capacity increase to the storm water system, localized flooding in the future is possible. City efforts could also focus on encouraging home owners within the watershed to limit permeable surfaces and increase the density of gardens, which would surely reduce the volume of water entering the storm water system during rain events.
This is some great insight to the issue of flooding in this area. Having maps and information that clearly show why and how an area floods is really helpful for government and NGOs to target areas that need work to prevent further flood events. The amount of pollution and sediment that result from these floods is probably pretty significant. It would be interesting to see if you could find information on the amount of excess nutrients entering into waterways around this area.
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