Flood Study Findings
The multi-agency Stormwater Management Technical Group has completed a 15-year study effort to define the extent of the major flooding problems in the county. The study shows that approximately 4,000 structures are flood prone in a 100-year storm event. Much of the flooding is concentrated in the older, highly-urbanized inner beltway communities targeted for revitalization.
Countywide Comprehensive Flood Damage Reduction Strategy
With the identification of these major flooding problems, the county is faced with the dilemma of how to protect public safety and welfare and, at the same time, continue to maintain an acceptable level of traditional services at a reasonable cost. The 3,000 residential flooding problems could require more than $100 million dollars and decades to correct. The county’s strategy to address flood conditions include:
Develop a long-term flood reduction program for the county
Evaluating flood mitigation alternatives
Performing a preliminary design of the solutions for those major problem areas
Recommending the most suitable flood mitigation alternatives
Seeking federal and state grants for project construction
A public education program, flood warning systems, and flood proofing and acquisition of the most severely flood prone homes are also potential options for reducing flood damage. Design work will also proceed on the most severely effected flooding areas.
Flood Damage Reduction
As part of a flood damage reduction effort, funding is appropriated in the Capital Improvement Project (CIP) budget to conduct planning and design for flood mitigation projects. Implementation of projects is subject to availability of funding. Projects are undertaken to solve isolated and sever residential flooding problems and to solve the most severe flooding problems.
A priority system was developed based on depth and frequency of flooding and number of flood prone structures within a geographic area. The 10 highest priority problems to be addressed first are shown below. These projects account for approximately 50% of the total number of flood prone structures countywide:
Anacostia Levee Improvements: Priority areas 1, 4, and 6 - protects approximately 300 structures
Northeast Branch - East West Highway: Priority area 2 - protects 191 structures