Stormwater Management in Arlington Ballston Pond Retrofit Project - PowerPoint PPT Presentation

Stormwater Management in Arlington Ballston Pond Retrofit Project

Chesapeake Bay Arlington’s watersheds watershed

Storm drain to local stream… Water in storm drains does not go to a treatment plant…

Current Stormwater Challenges  Existing Development . Most of Arlington was built before stormwater regulations existed. County streams are heavily impacted.  New state and federal regulations to reduce water pollution.  Aging Infrastructure. More than half of the storm sewer network is over 50 years old.  System Capacity .  C limate change . Climate models predict heavy rainfall events could increase sharply.

Regulatory Requirements  Virginia Stormwater Permit requires us to reduce stormwater pollution from existing and new development, as much as possible. The permit requirements are becoming more stringent.  Chesapeake Bay TMDL in development.  Master Transportation Plan includes recommendations for street trees and reduction of stormwater runoff.

Impacts from Stormwater Runoff Potomac River is our source of drinking water. Stormwater runoff erodes local streams, carrying sediment downstream, killing trees, and damaging sewer lines. Sediment is major pollutant of concern for Chesapeake Bay.

Stormwater Strategy  Maintain & replace stormwater infrastructure  Improve existing, and add new, stormwater treatment facilities  Stormwater controls for new development  Reduce risks from flooding  Restore stream corridors  Implement urban housekeeping best practices (such as street sweeping)  Outreach, education, and monitoring

Stormwater Master Plan Update  Stormwater Master Plan (1996) and Watershed Management Plan (2001) will be updated and combined into a comprehensive Master Plan.  Storm Sewer Capacity Analysis to study the County's current storm sewer pipes.  County-wide stream inventory to assess stream conditions and prioritize stream restoration projects.  Watershed retrofit plans to identify locations where stormwater treatment facilities can be added to help slow down and filter stormwater runoff.

Ballston Pond Retrofit  Improve ability of existing stormwater pond to improve water quality and remove nutrients  Treats several hundred acres of impervious area

Watershed Retrofit Plans  209 potential projects; 7 in design  8.1 acres of impervious area to be treated

New Stormwater Facilities

Stream Restoration Before After

Urban Housekeeping

Outreach and Education

Questions? Aileen Winquist awinquist@arlingtonva.us 703-228-3610 Gayle England gengland@arlingtonva.us 703-228-0773