Introduction to Flood Management
A floodplain is an integral part of the stream system. It provides storage capacity for high flows, helps reduce the erosive power of the stream during a flood, reduces the discharge of sediment during high flow periods and helps flood waters to move downstream. Floodplains also offer opportunities for wildlife habitat which can increase the biotic diversity of a stream. The 100-year floodplain is that land area adjoining the stream that has a 1% or greater probability of flooding in any given year. Floodplains provide a stream with buffer and water quality benefits as well.
It is the policy of the Prince George's County Government to preserve the 100-year floodplain as part of the natural system of a stream, and to further preserve it in a natural state in order to provide adequate storage for flood waters and sufficient carrying capacity to safely move flood waters downstream. Where existing structures in the 100-year floodplain cannot be protected in an environmentally sensitive and cost effective manner, the county may offer to acquire them to reduce the potential for property damage and eliminate potential obstruction of flood waters.
Future development is regulated within the ultimate 100-year floodplain. Prince George's County utilizes ultimate land-use conditions hydrology to determine flood discharges and to generate flood elevations for areas of the county under growth and development. Ultimate conditions hydrology reflects projected land-use conditions based on a community’s zoning maps and/or comprehensive land-use plans.
Prince George's County has, through the Maryland-National Capital Park and Planning Commission, established a policy to acquire stream valley parks throughout the county. Stream valley park acquisition permits public ownership of the floodplain, thus eliminating pressure for private development and providing recreational opportunities. Stream valley parks will continue to be an important component of the county’s recreation, open space and flood management programs.
Flood Management Goals
- Improve the quality of life in Prince George's County.
- Prevent future flood hazards from developing.
- Provide for expanded recreational and aesthetic opportunities in the county.
- Reduce or eliminate existing flood hazards.
- Reduce the economic losses associated with flooding events.
- Restore, preserve and enhance environmental quality wherever possible.
The Floodplain Ordinance was adopted by the County Council in April of 1989 and amended in 1993, 2000, 2011 and 2016. The Prince George's County Floodplain Ordinance is modeled after an ordinance suggested by the Maryland Department of the Environment (MDE). The Federal Emergency Management Agency (FEMA) contracted with MDE to review local floodplain ordinances to assure that they met FEMA requirements for eligibility for flood insurance.
Filling/Construction in the Floodplain
The ordinance generally discourages filling or construction in the floodplain, but allows for a variance under certain circumstances, for example, to meet an important public need. Where filling is needed within the floodplain, an equal volume of compensatory storage must be provided. Furthermore, an impact study is needed to ensure that the floodplain elevation will not be increased. The ordinance also contains requirements for the protection of buffers, wetlands and other natural features associated with the floodplain.
National Flood Insurance Program
Prince George's County has been participating in FEMA’s National Flood Insurance Program (NFIP) since 1972. The current effective Flood Insurance Rate Map (FIRM) can be reached by visiting the FEMA Floodplain Map of Prince George's County.
Known Floodprone Structures per Councilmanic District
Review a map depicting the known floodprone structures in the county.
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.
Elevation certificates are prepared by surveyors and document the ground elevation, floor elevation, and general building characteristics for a structure in relationship to the Base Flood Elevation.
Download files with more information about the designated floodplain areas in Prince George's County.
Find flood insurance rate maps and other flood insurance information.
Request in writing that a floodplain study be conducted by the county using GIS-based hydrology and hydraulic models with the property boundary (lot/parcel) highlighted on a tax map which clearly indicates the area of interest.
The warm weather of summer brings with it the start of another change in weather commonly known as “hurricane season." During this 6-month period from June through November, the likelihood for hurricanes and tropical storms that impact the eastern United States is extremely high.
All waterways and bodies of water are subject to flooding - a condition that occurs when the volume of water exceeds the capacity of the waterway channels or when tidal waters are pushed inland by coastal storms.
Qualified county staff are available at the Permit and Review Division to discuss your options and to help you plan and build a safe project while complying with the County Floodplain Management Ordinance.
Learn about the county's property protection projects (retrofitting, drainage, protecting against high wind, etc.), and substantial improvement/damage.
As part of its overall floodplain management program, the county provides a number of services to local residents and businesses.
The Stormwater Management Technical Group is an interagency technical group consisting of representatives from the Department of the Environment and the Maryland-National Capital Park and Planning Commission, which has been formed to study watersheds in the County. These technical studies include analysis of existing and planned land use, watershed hydrology, stream hydraulics, topographic analysis, evaluation of flood hazard mitigation alternatives, pollutant loading analysis, analysis of various water quality control techniques, and the National Pollutant Discharge Eliminate System (NPDES) Program.
Prince George’s County has approved Nuisance Flood Plan Phase I: Tidal Nuisance Flooding. This nuisance flood plan has been developed by the Prince George’s County Department of the Environment Sustainability Division. Prince George’s County, like other jurisdictions, has its own unique needs, resources, and strategies that can be used to develop and implement a nuisance flood plan. The plan is being developed in two phases. This part of the plan is Phase 1. It includes background on high tide flooding; identifies impacted areas; and provides recommended actions. Phase 2 will serve to build upon and expand this analysis to identify and track localized flood events and create a more robust nuisance flood plan.