Fairfax staff seek board recommendation for flood‑risk policy tied to $100M CIP and long‑term $600M need

County staff sought the Land Use Policy Committee’s recommendation for a new flood risk reduction policy intended to guide project prioritization and future regulations.

Ellie Cotting, a manager in the Department of Public Works and Environmental Services, told the committee the policy’s central goal is to establish a level of service that protects habitable structures against a 100‑year storm and to include a safety margin to account for climate change. Cotting framed flood risk management as a shared responsibility among the county, residents and private property owners and said the policy would help staff provide consistent guidance in the field.

Bill Hicks, director of Land Development Services, summarized three intended regulatory changes: (1) apply a climate change safety factor to the 100‑year design storm, (2) expand floodproofing requirements beyond FEMA‑mapped floodplains to known flood‑prone areas (published in a county GIS layer), and (3) seek to limit inundation of access routes to new structures so driveways are not submerged.

Staff also described prioritization and programs Joni Kalmbach of the Stormwater Planning Division described capital prioritization that focuses first on legal mandates and critical safety projects (for example, a county‑owned, state‑regulated dam repair), then on protecting habitable structures to the adopted service level, then on roads under county control and, finally, on yard flooding. Kalmbach reported the Flood Mitigation Assistance Program (FMAP), launched July 2024 and administered by the Northern Virginia Soil and Water Conservation District, has received more than 30 applications and dispersed about $80,000 in reimbursements for eligible measures (up to 50% of project cost, with a $5,000 cap).

Staff estimated long‑term need and timeline Staff said the county’s active flood‑related CIP list contains about $95 million in projects under design or construction and that addressing all confirmed structural flooding could require approximately $600 million in additional funding and take multiple decades to complete; staff cited a notional estimate of about 70 years to address the total program of work. They also said staff plan to seek FEMA Community Rating System verification this summer with the goal of a 25% premium discount for NFIP policyholders (moving from current class 6 at a 20% discount toward class 5 and a 25% discount).

Board queries and next steps Supervisors asked about the size of the climate safety factor; Hicks said staff are still refining the details but are considering roughly a 20% increase (a multiplier near 1.2) as a mid‑range projection and will return with more precise analysis next year. Other supervisors pressed on outreach and support for vulnerable communities (manufactured home parks), the use of stream gauges and regional coordination with bodies such as the Northern Virginia Regional Commission and the Army Corps of Engineers.

At the meeting’s close, board members generally supported moving the policy forward and asked staff to return with regulation‑level details and clearer cost estimates for public review.