Stormwater Management Program

This countywide program addresses the design, development, improvement, operation, inspection, maintenance, and oversight of the stormwater management system.


Report a Problem

Residents who have a complaint regarding stormwater are encouraged to contact the county by telephone, complete a stormwater request on LEx (Loudoun Express Request), or send an email.

  1. Stormwater Management Plan
  2. Related Documents
  3. Resources

Six Minimum Control Measures

Under the National Pollutant Discharge Elimination System (NPDES) Phase II regulations, Loudoun County must prepare a stormwater management program containing elements that address the following six technical areas:

  1. Construction site runoff control
  2. Illicit discharge detection and elimination
  3. Pollution prevention / good housekeeping
  4. Post-construction runoff control
  5. Public education and outreach
  6. Public participation / involvement

Stormwater Management Plan

Each of these areas, identified as minimum control measures in the NPDES Phase II regulations, is discussed in the Loudoun County Stormwater Management Plan (PDF). For each of the minimum control measures, communities must identify best management practices (BMPs) and measurable goals that reflect the communities' choices about how to satisfy the regulatory requirements. These BMPs and goals form the basis on which the success of the Phase II program can be evaluated in each community, which is ultimately the degree to which the community is satisfying the water quality requirements of the Clean Water Act.

Environmental Agencies

To assist communities, the Virginia Department of Environmental Quality (DEQ), along with the Environmental Protection Agency (EPA), has specified the minimum requirements for each of the six control measures along with recommended program elements. While Virginia's two environmental agencies, VDEQ, and the Virginia Department of Conservation and Recreation (VDCR) continue the process of developing a unified Virginia BMP manual, the EPA has developed and is continuing to revise a list of potential BMPs that communities might use to satisfy the Phase II program requirements.

Additionally, Loudoun County adopted Chapter 1096: Stormwater Management Ordinance on October 20, 2003.

Best Management Practices

To arrive at appropriate best management practices, the county engaged in an extensive assessment of the existing stormwater management operations, ordinances, and programming against the compliance requirements of the General Virginia Stormwater Management Program (VSMP).


A best management practice (BMP) is a technique, process, activity, or structure used to reduce the pollutant content of a stormwater discharge. BMPs include simple nonstructural methods, such as good housekeeping and preventive maintenance. BMPs may also include structural modifications, such as the installation of bio-retention measures. BMPs are most effective when used in combination with each other, and customized to meet the specific needs (drainage, materials, activities, etc.) of a given operation. The focus of EPA's general permits is on preventive BMPs, which limit the release of pollutants into stormwater discharges. BMPs can also function as treatment controls.