Loudoun County Board of Supervisors Updates Stormwater Management Regulations | The Locally Times
The updated stormwater ordinance, effective July 1, mandates stricter compliance standards for all new development projects exceeding 2,500 square feet of land disturbance.
The Loudoun County Board of Supervisors officially approved amendments to the existing stormwater management ordinance, with the new requirements taking effect on July 1. These regulatory changes apply to all land development projects that disturb at least 2,500 square feet of soil within the county jurisdiction. According to the 2024 legislative summary, the primary objective of this policy shift is to align local practices with the 10% increase in regional rainfall intensity observed over the last 20 years. Developers must now submit updated drainage plans that account for a 50-year storm event, increase from the previous 10-year standard. The Loudoun County Department of Building and Development estimates that the administrative cost for processing these enhanced permit applications will rise by approximately $450 per project. Furthermore, the county has allocated $1.2 million in the 2025 fiscal budget to support the additional engineering reviews required by the July 1 deadline. Projects that fail to meet these new criteria will face a daily fine of $500 until the site reaches full compliance with the updated stormwater code. By implementing these changes, the county aims to reduce the $3.4 million in annual property damage currently attributed to localized urban runoff. All construction sites currently in the planning phase as of June 1 must demonstrate that their stormwater retention systems can handle a 20% increase in volume compared to previous mandates. The Loudoun County Board of Supervisors also confirmed that 100% of new commercial developments must incorporate green infrastructure, such as bioswales or permeable pavement, to mitigate runoff. These requirements are detailed in the 2024 Stormwater Management Ordinance Amendment document, which spans 42 pages of technical specifications. For projects valued over $500,000, the county now requires a third-party inspection report to be filed within 30 days of project completion. The Loudoun County Board of Supervisors expects that these measures will protect 15,000 acres of sensitive watershed land over the next 10 years. Failure to adhere to the July 1 implementation date could result in the suspension of building permits for up to 90 days. The county will host 3 public workshops throughout June to assist developers in understanding the new technical requirements. These sessions are designed to ensure that 100% of active contractors are prepared for the transition. By prioritizing these infrastructure improvements, the Loudoun County Board of Supervisors intends to maintain the integrity of the local water supply for the 430,000 residents living in the region.