Facility maintenance transitions from reactive to proactive

As a primary function, stormwater facilities retain water to slow water flow, which helps lessen erosion energy, allows for pollution elements of sediment and nutrients to precip-itate, and promotes groundwater recharge through infiltration. But accumulated sediment can cause serious problems. Facilities that are blocked or have had their emergency spillway activated and eroded may require...

Fairfax County is a rapidly developing municipality located in northern Virginia with a population of over 1.1 million and nearly 450,000 housing units. The county maintains 1,465 stormwater ponds in order to remain in compliance with its Municipal Separate Storm and Sewer (MS4) permit. The county’s stormwater program designs and maintains publicly owned stormwater facilities as well as...

In 2018, Fairfax County soils were mapped in ArcGIS, providing over 24,000 soil shapes. This spatial information was joined with a description of the 108 soils that are found in the county, as characterized by the 2013 Description & Interpretive Guide to Soils in Fairfax County by the Fairfax County Department of Public Works. In the guide, soils are rated for erosion potential, water...

Each Fairfax County facility was delineated according to watershed. By clipping the facility’s soils information and characteristics, maps were generated to interpret a site and create reports to help determine the site’s ground truth. One problematic site is located in Centreville, in the western part of the county, where an enhanced extended detention pond (dry) is used for...

Though the ArcGIS-based maps initially take time to create, they are exceedingly helpful in characterizing a site. The final goal is to have the GIS-generated data be a stand-alone tool, created as reports that can be autogenerated and for each facility’s maintenance plan.

Eric Caldwell is the assistant project manager in Fairfax County Department of Public Works and Environmental Services’ Stormwater Management Branch in the US state of Virginia.