Flood Management

• Introduction to Flood Management in Prince George's County
• Local Flood Hazards, Mapping, and History of Flooding
• FEMA Website
• Flood Insurance Rate Maps and Flood Insurance (NFIP, CRS, CTC, FIRMs, LOMA/LOMR)
• FEMA Floodplain Map of Prince George's County
• Elevation Certificates
• Known Floodprone Structures
• Flood Warning Systems
• Countywide Flood Damage Reduction Strategies
• Property Protection Projects (retrofitting, drainage, protecting against high wind, etc.), and Substantial Improvement/Damage
• Permitting
• GIS and Mapping Components
• Watershed Studies
• Drainage Maintenance
• Public Outreach
• Floodplain Directory of Information Services
• Hurricane Season Special Warnings
• Disaster Do’s and Don’ts
• Disasters - Prepare & Plan
• Frequently Asked Questions (FAQs)
• Download Flooding Brochure (PDF)

Introduction to Flood Management in Prince George's County

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 water. Future development is not permitted within the ultimate 100-year floodplain. Prince George's County has used ultimate conditions hydrology to determine flood discharges and to map areas of the County experiencing rapid urban and suburban growth. Ultimate conditions hydrology and mapping uses projected land-use conditions based on a community's zoning maps and/or comprehensive land-use plans in determining flood discharges, flood elevations, and corresponding areas at risk.

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 for Prince George's County is guided by the following goals:

• Reduce or eliminate existing flood hazards;
• Prevent future flood hazards from developing;
• Reduce the economic losses associated with flooding events;
• Provide for expanded recreational and aesthetic opportunities in the County;
• Restore, preserve and enhance environmental quality wherever possible; and
• Improve the quality of life in Prince George's County.

The Floodplain Management Ordinance was adopted by the County Council in April of 1989 and amended in 1993 to conform with State and Federal requirements. The ordinance replaced those portions of the County Code that dealt with floodplain management. The previous code provisions have been deleted. The new 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 and assure that they met FEMA requirements for eligibility for flood insurance.

The ordinance prohibits filling or construction in the floodplain generally, 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. Revisions have been made to other sections of the Code, such as the Subdivision Ordinance, to bring them into conformance. The ordinance also contains requirements for the protection of buffers, wetlands and other natural features associated with the floodplain.

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 clicking on the FEMA Floodplain Map of Prince George's County link.

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Local Flood Hazards, Mapping, and History of Flooding

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:

• Riverine or nontidal bodies of water are those that drain upland areas and are not influenced by coastal and tidal processes. In addition to rivers, nontidal bodies of water include streams and creeks and other small flowing waters. Flooding can also occur in localized low spots, even if the area is not adjacent to a body of water.

• Coastal flooding affects tidal bodies of water, including the tidal reaches of the Potomac River and the Patuxent River in Prince George’s County. The Potomac River is subject to tidal flooding along its entire length in the County, and the Patuxent River is subject to tidal flooding up to the confluence of Western Branch.

The Prince George’s County Department of Environmental Resources recognizes and manages riverine flood hazard areas that are designated in two ways:

• Areas identified as vulnerable to flooding from the 1% annual chance flood (100-year floodplain) that are shown on the County’s Flood Insurance Rate Maps (FIRMs) prepared by FEMAs National Flood Insurance Program (NFIP); and

• Other flood maps based on studies prepared by the County to evaluate the impact of future development. These maps often include areas not studied by the NFIP.

The first Flood Insurance Study and Flood Insurance Rate Maps (FIRMs) for the County were dated August 4, 1972 and prepared by the U.S. Department of Housing and Urban Development (a precursor agency to FEMA). Since that time, updates to several panels have been completed. The most recently revised and reprinted map panels are dated September 6, 1996.

Starting in the 1980s, the Department of Environmental Resources began to obtain State grants and use County funding to prepare more up-to-date watershed studies to delineate floodplains. The County’s studies and maps, prepared with detailed base map data and detailed engineering models, account for future watershed development. They also are the basis for the State’s regulation of nontidal waterways. Watershed studies have been prepared for the following bodies of water:

• Piscataway Creek (adopted July 1986);
• Henson Creek (adopted July 1986);
• Western Branch of the Patuxent River (adopted July 1983);
• Tinkers Creek (adopted September 1980);
• Anacostia River;
• Folly Branch;
• Collington Branch;
• Bald Hill Branch;
• Southwest Branch;
• Charles Branch;
• Oxon Run; and
• Beaverdam Creek.

The figure below shows the extent of flooding as depicted on the latest FEMA Flood Insurance Rate Maps. For more information on FEMA Flood Insurance Rate Maps, how to locate your property on a FIRM, a description of the flood zones, and information on amendments or revisions to the FIRM, visit the section titled “Flood Insurance Rate Maps and Flood Insurance.”

 Flood Hazard History in Prince George’s County

Prince George’s County has experienced some riverine and stream flooding in recent decades, although sound management of flood hazard areas and construction of flood control projects has reduced potential losses. Notable riverine and coastal flooding has occurred several times since 1933.

• August 1933 – This unnamed hurricane caused flooding along the Potomac River and throughout the Chesapeake Bay; the Livingston Bridge on Piscataway Creek also flooded.
• October 1954 – Hurricane Hazel raised water levels in the Potomac River Basin; statewide, the storm caused 6 deaths and an estimated $11.5 million in damage.
• August 1955 – Hurricane Connie caused riverine flooding that inundated a large commercial section of Upper Marlboro and flooded several buildings along Piscataway Creek; surge reached 4 feet above normal at the confluence of Patuxent River with Western Branch.
• August 1971 – Heavy rain and flooding.
• June 1972 – Tropical Storm Agnes; this storm of record brought high water levels along the Patuxent and Potomac River basins; statewide, it caused 19 deaths and $80 million in damage; in Prince George’s County, the storm caused more than $10 million in damage (see box).
• September 1975 – Hurricane Eloise; heavy rain and flooding; Prince George’s County was included in the major disaster declaration.
• September 1978 – Hurricane David; Prince George’s County was included in the major disaster declaration.
• November 1985 – Hurricane Juan affected the Potomac River Basin; Prince George’s County was included in the major disaster declaration.
• September 1996 – Hurricane Fran; remnants of this large storm caused flooding along the Potomac River Basin; Prince George’s County was included in the major disaster declaration.
• September 2003 – Hurricane Isabel produced widespread wind damage, power outage, and localized flooding.
• June 2006 – Heavy rain and flooding.

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Flood Insurance Rate Maps and Flood Insurance (NFIP, CRS, CTC, FIRMs, LOMA/LOMR)

• National Flood Insurance Program (NFIP) Information
• Community Rating System (CRS)
• Cooperating Technical Community (CTC) Program
• Is your property in a flood hazard area?
• Flood Insurance Rate Maps (FIRMs)
• Letters of Map Amendment and Revision (LOMA/LOMR)
• Elevation Certificates
• Known Floodprone Structures

National Flood Insurance Program (NFIP) Information

In 1968, Congress created the National Flood Insurance Program (NFIP) in response to the rising cost of taxpayer-funded disaster relief for flood victims, and the increasing amount of damage caused by floods. The NFIP makes Federally-backed flood insurance available in communities that agree to adopt and enforce floodplain management ordinances to reduce future flood damage. National Flood Insurance is available in more than 20,000 communities across the United States and its territories.

The NFIP is managed by the Federal Emergency Management Agency's  Federal Insurance Administration  and Mitigation Directorate. The Federal Insurance Administration manages the insurance component of the NFIP, and works closely with FEMA's Mitigation Directorate, which oversees the floodplain management aspect of the program.

The NFIP, through partnerships with communities, the insurance industry, and the lending industry, helps reduce flood damage by nearly $800 million a year. Further, buildings constructed in compliance with NFIP building standards suffer 77 percent less damage annually than those not built in compliance. Every $3 paid in flood insurance claims saves $1 in disaster assistance payments.

The NFIP is self-supporting for the average historical loss year, which means that operating expenses and flood insurance claims are not paid for by the taxpayer, but through premiums collected as flood insurance policies. For more information on NFIP, visit the FEMA website at http://www.fema.gov/about/programs/nfip/index.shtm.

Top 10 Facts Everyone Should Know About the National Flood Insurance Program

•  Everyone lives in a flood zone.
•  Flood damage is not covered by homeowners insurance policies.
•  You can buy flood insurance no matter what your flood risk.
•  There is a low-cost policy for homes in low to moderate risk areas.
•  Flood insurance is affordable.
•  Flood insurance is easy to get.
•  Contents coverage is separate, so renters can insure their belongings too.
•  Up to a total of $1 million of flood insurance coverage is available for non-residential buildings and contents.
•  There is usually a 30-day waiting period before the coverage goes into effect.
•  Federal disaster assistance is not the answer.

1. Everyone lives in a flood zone.

•  You don't need to live near water to be flooded.
•  Floods are caused by storms, melting snow, hurricanes, and water backup due to inadequate or overloaded drainage systems, dam or levee failure, etc.

2. Flood damage is not covered by homeowners policies.

•  You can protect your home, business, and belongings with flood insurance from the National Flood Insurance Program.
•  You can insure your home with flood insurance for up to $250,000 for the building and $100,000 for your contents.

3. You can buy flood insurance no matter what your flood risk.

•  Whether your flood risk is high, medium, or low, you can buy flood insurance as long as your community participates in the National Flood Insurance Program.
•  It's a good idea to buy, even in low or moderate risk areas: approximately 25 percent of all flood insurance claims come from low to moderate risk areas.

4. There is a low-cost policy for homes in low to moderate risk areas.

•  The Preferred Risk Policy is available for just over $100 a year.
•  You can buy up to $250,000 of coverage for your home and $60,000 of coverage for your contents.

5. Flood insurance is affordable.

•  The average flood insurance policy costs a little more than $300 a year for about $100,000 of coverage.
•  In comparison, a disaster home loan can cost you more than $300 a month for $50,000 over 20 years.

6. Flood insurance is easy to get.

•  You can buy NFIP flood insurance from private insurance companies and agents; call yours today!
•  You may be able to purchase flood insurance with a credit card.

7. Contents coverage is separate, so renters can insure their belongings too.

•  Up to $100,000 contents coverage is available for homeowners and renters.
•  Whether you rent or own your home or business, make sure to ask your insurance agent about contents coverage. It is not automatically included with the building coverage.

8. Up to a total of $1 million of flood insurance coverage is available for non-residential buildings and contents.

•  Up to $500,000 of coverage is available for non-residential buildings.
•  Up to $500,000 of coverage is available for the contents of non-residential buildings.

9. There is usually a 30-day waiting period before the coverage goes into effect.

•  Plan ahead. Don't be caught without flood insurance when a flood threatens your home or business.

10. Federal disaster assistance is not the answer.

•  Federal disaster assistance is available only if the President declares a disaster.
•  More than 90 percent of all disasters in the United States are not Presidentially declared.
•  Flood insurance pays even if a disaster is not declared.

Source: FEMA: NFIP

Community Rating System (CRS)

The Community Rating System (CRS) is a program started in 1990 under the NFIP. The program was designed to recognize and encourage community floodplain management activities that exceed the minimum NFIP standards. Under the CRS, flood insurance premium rates are adjusted to reflect the reduced flood risk resulting from community activities that meet the three goals of the CRS: (1) reduce flood losses; (2) facilitate accurate insurance rating; and (3) promote awareness of flood insurance.

There are ten CRS classes: class 1 requires the most credit points and gives the largest premium reduction, while class 10 is the entry level into the CRS and carries no premium reduction. Prince George's County is currently rated Class 5 under the CRS, which translates to a 25% reduction in flood insurance rates for local residents and businesses. The Class 5 rating places Prince George's County in the top 2% of over 1000 communities nationwide that participate in the CRS. For more information on the CRS, visit the FEMA web site at http://www.fema.gov/business/nfip/.

The Cooperating Technical Community (CTC) Activities in the County

With GIS-based H&H models, the County has received grant funding from FEMA under two separate programs to automate the floodplain information in the County: the Cooperative Digital Flood Mapping Program and the Cooperating Technical Community (CTC) Program. Under the CTC Program, the County is proposing to conduct several additional activities using these GIS models. Specifically, these activities are:

• Completed a countywide GIS-based 2-ft topography using the newly developed technology such as LIDAR (total cost is approximately $400,000). FEMA, the Maryland State Highway Administration, the Maryland-National Capital Park & Planning Commission and the County have already agreed on cost-sharing;
• Re-do the entire FEMA study (normally referred to as the Flood Insurance Study) using our GIS-based hydrologic and hydraulic (H&H) models. The total cost will be approximately $250,000. This cost includes the new FEMA floodplain mapping in digital form. To date, the County has submitted to FEMA the following Watershed Studies: Western Branch; Charles Branch; Anacostia River; Henson Creek; Piscataway Creek; and Patuxent River mainstem;
• The County will conduct a technical review of all FEMA map amendment (LOMA) and map revision (LOMR) requests and then update the changes. The County will charge the developer a review fee that is same as the fee schedule currently employed by FEMA;
• The County will continue to conduct floodplain studies for developers using our GIS-based H&H models. The results of the studies will be incorporated into the LOMA or LOMR process (the County will charge approximately $3,000 for each study);
• The County has converted the GIS-based H&H models (WMS-Watershed Modeling System) into a more user friendly environment such as ARC-VIEW to allow any jurisdictions that have standard PCs to easily utilize these models. The cost for this conversion was approximately $100,000; With this new floodplain database, the County will provide floodplain inquiry services to homeowners, insurance companies, and lending institutions for a minimal fee. The County is in the process of converting the new GIS-based models; and
  
• The County will conduct a detailed Damage Assessment Analysis after a flood event using this GIS-based H&H models. FEMA will need to provide the County with the necessary training.

Is Your Property in a Flood Hazard Area?
Special Flood Hazard Areas are areas located within the 100-year floodplain, defined as any area that has a one percent chance of flooding in any given year. Smaller scale floods (50-year and 10-year) have a greater chance of occurring in any given year and can also pose a significant flood hazard to persons and property in close proximity to channels and streams. Additionally, floods larger than the mapped 100-year event can occur.

First and foremost, you should become informed as to the flood hazard potential on your property. The Prince George’s County Department of Public Works and Transportation will review floodplain information and studies available in their files to determine the location of your property with respect to the floodplain as established in the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps. You may contact the Prince George’s County Department of Public Works and Transportation at (301) 883-5777 for assistance with this information.

Any information provided by the County does not constitute an assurance or representation that flooding may or may not occur on your property during any given event, but should assist you as a general matter in determining the need for flood insurance by assessing the extent of flooding potential on your property.

Flood Insurance Rate Maps (FIRMs)

The FEMA Flood Insurance Rate Maps (FIRMS) are the official maps showing the community’s Special Flood Hazard Areas . These maps are utilized as the basis for local floodplain management regulations and mitigation efforts, to assess flood risk, and to determine if flood insurance is required for structure(s) on a property. Although these maps are not property specific (e.g. no lot boundaries), by using the major roads and flooding sources for reference, users can get an idea of the flood risks in their area. These maps are available to view online at the Map Service Center ( msc.fema.gov ) or at the Prince George’s County Department of Environmental Resources' offices in Largo, Maryland. Additionally, the Map Service Center site has an address search feature that allows a user to find the correct FIRM panel using their address in an on-line search tool.

For additional assistance with using the FIRMs, please contact the FEMA Map Assistance Center at 1-877-FEMA MAP, visit the following website ( www.fema.gov/hazard/map/firm.shtm ) , or contact Yanping Zhang at (301)883-5787 or (301)883-3311

Letters of Map Amendment and Revision (LOMA/LOMR)

In some cases, a lender determines that a property is in the Special Flood Hazard Area (SFHA), or 100-year floodplain, and requires the owner to purchase flood insurance. If the property owner wishes to dispute the fact that they are in the SFHA, they can apply for a Letter of Map Amendment (LOMA) or a Letter of Map Revision Based on Fill (LOMR-F), if fill placement is the basis of the request.

Forms for this application process may be found on FEMA’s website at www.fema.gov/plan/prevent/fhm/frm_form.shtm .

You may also access tutorials designed to assist in the preparation of these forms at www.fema.gov/plan/prevent/fhm/ot_main.shtm . This tutorial will guide you through the application and provide tips on filling out the forms.

Upon receiving a completed application, FEMA reviews property-specific information and makes a final flood zone determination for the property. Once an application is received with all the required supporting data, the LOMA or LOMR-F is normally issued within 60 days. If the LOMA or LOMR-F removes the SFHA designation from the property, it can then be presented to the lender as proof that there is no Federal flood insurance requirement for the property. Bear in mind that even though a LOMA or LOMR-F may remove the Federal requirement for flood insurance, a lender retains the prerogative to require flood insurance.

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Elevation Certificates

Elevation certificates are prepared by surveyors and document the ground elevation, floor elevation, and general building characteristics for a structure. The County has approximately 763 elevation certificates on file electronically and available to the public. Property owners may use the certificates for flood insurance rating purposes, and the County uses the detailed information to evaluate mitigation options. Elevation certificates are available for the structures listed in the following table. For more information on elevation certificates please call Mike Colgan  at (301)883-5944 or (301)883-3311.

Links to Elevations Certificate (PDFs)

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Known Floodprone Structures

• Addresses for Floodprone Structures

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Flood Warning Systems

Flood Warning System at Western Branch

The Western Branch Comprehensive Watershed Management Plan was prepared by the Prince George's County Stormwater Management Technical Group in 1981. Even though the US Army Corps of Engineers had constructed a floodway through Upper Marlboro to carry flood waters away, there are 73 commercial structures, 33 residential structures, and 39 garages/sheds subject to flooding in the Upper Marlboro Area. To date, no additional flood control devices have been proposed or planned to mitigate these known flooding hazards. A consulting engineering firm, Engineering Technology Associates (ETA), has completed a hydrologic and hydraulic analysis or watershed study of Western Branch. This study was not designed to produce or evaluate possible solutions that will minimize flooding problems in the Upper Marlboro area. Rather, this study was meant to determine the flood levels in the Western Branch at Upper Marlboro. This analysis will form the technical basis to be used by the County to select and evaluate possible solutions to the flooding problems in the Watershed. Until the final study and selection of alternatives is completed and ready for implementation, it would be prudent to have an interim program for limiting the extent of flood damage that may occur. Such an interim program to limit flood damage has been proposed in the form of a flood warning system. The Flood Warning System would provide for the monitoring of rainfall and stream flow data to determine if a flood is imminent. The Flood Alerting System will allow the County to use the information gained with the Flood Warning System to alert those in danger that the danger exists.

Preliminary analysis of how the flood warning system would work indicates that Upper Marlboro could reasonably expect ten hours of warning before a flood. Inasmuch as the there are several auto dealerships in and near the 100-year floodplain on Maryland Route 301 in Upper Marlboro, many hundreds of thousands of dollars in flood damage could be avoided simply by moving the cars out of danger.

When completed, the flood warning system will be integrated into the County's Emergency Management System. In this way, when flood waters begin to rise, County public safety officials who use the Emergency Management System will have information as soon as it becomes available and will have a comprehensive understanding of the status of the flood.

The U.S. Army Corps of Engineers has completed a study of the efficacy and desirability of installing a flood warning system in Western Branch. The study indicated that such a flood warning system is feasible and desirable. The flood warning and alerting system for the Western Branch has been designed and partially implemented and may be a model for other watersheds within the County. The flood warning and alerting system will continue to provide an additional margin of safety and will be retained as a permanent feature of the Western Branch Flood Management System.

Prince George’s County has received state grant funding for the upgrade of the Western Branch Flood Warning System. It will be in full operation June 1, 2008 and may be viewed online at http://www.afws.net/data/md/Prince_Georges.htm

Flood Warning System near/at City of Laurel

Due to severe and frequent flooding problems occurring in low lying areas of the City of Laurel and areas such as Woodland Grove Apartments (immediately outside the City limits), a separate flood plan was developed for this area. The plan included the services of the Community Alerting Network to provide telephone notification to impacted residents and businesses. This system has been implemented through the cooperative efforts of the Washington Suburban Sanitary Commission (WSSC), the City of Laurel and the Office of Emergency Management.

Flood Warning System at Anacostia River

According to a preliminary Anacostia River Watershed Study prepared by Greenhorne and O'Mara, Inc. in 1994, more than 3,000 structures may be floodprone within the Prince George's County portion of the Anacostia Watershed. So far, no effective flood control measures have been proposed to mitigate these flooding hazards. Given the fiscal constraints of flood management in the Anacostia, a flood warning system is a cost effective flood hazard mitigation measure. The County is working with the U. S. Army Corps of Engineers to develop the flood warning system for this watershed. The flood warning system at Anacostia River is now in full operation and may be viewed online at http://www.afws.net/data/md/Prince_Georges.htm .

Wide Area Rapid Notification (WARN)

Prince George’s County residents will receive immediate notification of emergencies through a new state-of-the art communications system operated by the County’s Office of Homeland Security. This is possible with the Wide Area Rapid Network (WARN) system.
 
The computerized system allows County public safety agencies to transmit a wide range of public safety information messages rapidly and instantly to residents. WARN goes beyond traditional systems to instantly communicate with as many as 10,000 residents per minute. The internal system intuitively converts text messages to voice, allowing notification to multiple devices, including phone lines and text messaging devices.
 
The residents of Prince George’s County are now only a phone call away when they need to get important information into their hands. WARN allows the Office of Homeland Security to keep in touch during localized or countywide emergencies. The ability to alert communities instantly and get County personnel into action fast can make a critical difference in public safety.

  WARN at a glance:

• WARN is a suite of emergency products for Communications and Information Continuity, offering command and control by and between government, public safety agencies and other vital public and private sector groups. The system can provide notification of Homeland Security and health emergencies, hazardous material/chemical spills, accidents, fires, and floods. The system can be used for meeting announcements, the status of government, treatment and vaccination coordination efforts, and general alerts.
• WARN Broadcast (Public) allows instant and pinpointed public notification to all citizens using a predetermined grid or mapped database for a geographic area. The system allows instant calling for a wide range of public informational and safety purposes.
• WARN Command is a more specialized version of WARN and is used by public safety command and control centers for business continuity. The system, which includes all of the power of WARN Broadcast plus communication escalations, connects to every voice and text device and facilitates message cascading and call bridging.
• WARN Geographical Information System uses geographical maps to issue instant notifications to the public based on geographic location.

In the event of a major flood or other flood-related hazard, individuals registered in the system are notified via phone, fax, e-mail, or pager. If you would like to be added to our database, please fill in the form below. You may include more than one contact number or e-mail address. If you decide to add your contact numbers to our database, please provide us with your name and address so that we can associate your number with your address.

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Countywide Flood Damage Reduction Strategies

Flood Study Findings

The multi-agency Stormwater Management Technical Group has completed a fifteen-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: evaluating flood mitigation alternatives; recommending the most suitable flood mitigation alternatives; performing a preliminary design of the solutions for those major problem areas; seeking Federal and State grants for project construction; and develop a long-term flood reduction program for the County.

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.

Prince George's County Hazard Mitigation Plan (PDF)

Flood Damage Reduction Components Commencing in FY1995

Adequate funding has been appropriated in FY1995 Capital Improvement Project (CIP) to conduct planning and design for Phase I of the implementation of the Plan. However, further implementation of the Plan, including construction of this phase, will be subject to the availability of funding. Phase I has two components:

A. Solve Isolated and Severe Residential Flooding Problems

• Involves the acquisition or flood proofing of 23 homes at a cost of $2.7 million.

B. Solve The Ten Most Severe Flooding Problems First

A priority system was developed based on depth and frequency of flooding and number of floodprone structures within a geographic area (see "Prioritization Criteria/Schedule of Implementation" in Section III). The 10 highest priority problems to be addressed first are shown below with a total cost ranging from $40 million to $60 million. These projects account for approximately 50% of the total number of floodprone structures countywide.

• Anacostia Levee Improvements. Priority areas 1, 4, and 6 - protects 1,363 structures;
• Northeast Branch - East West Highway. Priority area 2 - protects 191 structures;
• Northeast Branch - Bladensburg. Priority area 3 - protects 58 structures;
• Oxon Run - Forest Heights. Priority area 5 - protects 43 structures;
• Beaverdam - Landover. Priority area 7 - protects 40 structures;
• Paint Branch - Cherry Hill Road. Priority area 8 - protects 18 structures;
• Indian Creek - U. S. Route 1. Priority area 9 - protects 29 structures; and
• Northwest Branch - East West Highway. Priority area 10 - protects 92 structures.

Recommended Future Actions

• Although the County will not begin work on structural solutions for lower priority problems for some time, existing nonstructural flood damage reduction programs will still continue. These programs include: technical assistance, low cost flood insurance, public education, emergency management assistance, improved flood warning systems, research and development of new technologies,; development review, floodplain regulation and assessments of redevelopment and future land use impacts.
  

B. Continue to Conduct and Update Watershed Management Plans

• To date, plans have been produced for Western Branch, Piscataway Creek, Henson Creek, Charles Branch, and Oxon Run. However, the plans for Oxon Run and Charles Branch have not been adopted by the County Council. The Oxon Run study will be ready for adoption by the County Council in the near future. Most of the problems in Piscataway Creek and Henson Creek as well as approximately 40% of the problems in Western Branch have been corrected. The Anacostia River study has the hydrology and hydraulics portion completed. The Beaverdam Creek plan is under preparation and is scheduled to be completed in 18 months; however, the hydrology and hydraulics portions are completed.
  

C. Continue All Existing Programs at Current Service Levels

• Maintain capacity to address problems not specifically identified in the comprehensive studies.
  

D. Funding Challenges (debt service, maintenance and operations)

Using existing funding and staff, it will take 40 years to completely address the problems. This is too slow a response given the hazards involved. A better goal would be to gradually expand the County's capacity to address these flooding problems eventually resulting in a growth of flood management capital expenditures from the current $5 million dollars to approximately $10 million dollars each year. At that program level of expenditure, these major flooding problems would be addressed in 20 years. The cost of the construction to mitigate the flooding for the top 10 priority areas and the remaining problem areas can be funded from the following sources. However, none of the above actions deals directly with the 980+ commercial/industrial structures.

1. Obtain State and Federal grants.
2. $10 million in Federal grants and $2 million in State funding may be available. Additional State and Federal grants could become available through appropriate Federal and State legislation.
3. Prioritize program objectives.
4. Require reduced funding for other programs such as regional program, priority III program, etc.
5. Restructure plan review fees and fee-in-lieu amounts; less than $1 million may be available from this source.
6. Impose Ad valorem tax increase and bond sales.

Property Protection Projects (retrofitting, drainage, protecting against high wind, etc.), and Substantial Improvement/Damage

In some cases, retrofitting existing buildings or regrading a yard can help reduce the potential for flood damage to structures and their contents. Retrofitting techniques include elevating buildings above flood levels, wet or dry floodproofing (commercial structures only), and installing backflow preventers to protect floors and contents from sewer backups. A building permit may be required for retrofitting and structural projects.

There are also temporary measures that can help to protect your property during a flood event. You can plan ahead about where and how you will move furniture out of harm's way; keep materials like sandbags, plywood, plastic sheeting and lumber handy for emergency waterproofing; and clear brush and debris away from storm drains and ditches so water can drain away from the structure.

The following guides contain more information on protecting your property:

• “Residential Drainage: A Homeowner’s Guide to Drainage Problems and Solutions” available from Prince George’s County. This free guide can be obtained by calling Paul DeSousa at (301)883-5871 or (301) 883-5832
• "Homeowner's Guide to Retrofitting: Six Ways to Protect Your House from Flooding" (FEMA Publication #312), includes information on protecting a structure from flooding and information about available financial assistance. This free guide can be obtained by calling 1-800-480-2520 or online at www.fema.gov/irl/viewRecord.do?id=1420 .

For additional questions about these types of projects, or for information on permitting, please contact the Prince George’s County Department of Environmental Resources at (301)883-5776.

Substantial Improvements

Homeowners who are planning substantial improvements to their structure should contact the Permits and Review Group for a residential building permit. Elevation or floodproofing may be required if you plan to substantially improve your existing structure (the cost of the improvement or add-on is 50% of the value of the existing structure).

If your property is substantially damaged (50% of the value of the building), Federal regulations may require you to elevate or floodproof before you can rebuild. The document titled “Answers to Questions about Substantially Damaged Buildings” (FEMA-213, May 1991) will help answer questions on this topic and can be obtained free by calling 1-800-480-2520 or by going online to http://www.fema.gov/hazard/flood/pubs/lib213.shtm .

For additional questions about substantial improvements, or for information on permitting, please contact Paul DeSosa at (301) 883-5871 or (301) 883-5832.

Permitting

Qualified County staff are available at the Permit and Review Group to discuss your options and to help you plan and build a safe project while complying with the County Floodplain Management Ordinance.

Building permits ensure safe construction inside and outside floodplains. The Prince George’s County permitting process is designed to ensure that all construction in Prince George’s County is safe. A permit is required for all new construction and, most of the time, you must obtain a permit for repairing or replacing existing features. Before you begin construction or add-on to an existing building, find out which permits are required by contacting the Permit and Review Group.

In addition to regular building permits, special regulations apply to construction in floodways and the floodplain. No construction, including filling, is allowed in the mapped floodway without an engineering analysis that shows the project will not increase flood damage elsewhere. Any activity outside the floodplain but within a natural or man-made watercourse also requires a permit.

Homeowners who are planning substantial improvements should contact the Permit and Review Group for a residential building permit. Elevation or flood proofing may be required if you plan to substantially improve your existing structure (the cost of the improvement or add-on is 50% of the value of the existing structure). If your property is substantially damaged (50 percent of the value of the building), Federal regulations may require you to elevate or flood proof before you can rebuild.

To report illegal floodplain development or to verify that proper construction permits have been issued for a project, contact the Prince George’s County Department of Public Works and Transportation at (301) 883-5777. An inspector will investigate.

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GIS and Mapping Components

GIS-based Floodplain Submittal

The procedure/required information to request a floodplain study to be conducted by the County is GIS-based Floodplain Submittals summarized as follows:

Request in writing that a floodplain study be conducted by the County using the Geo-STORM models with the property boundary (lot/parcel) highlighted on a tax map or other map which clearly indicates the area of interest. The address for sending the request is:

Program Support Section

Environmental Services Group
Department of Environmental Resources
9400 Peppercorn Place, Suite 610
Largo, Maryland 20774

Once a letter is received, along with the floodplain study fee (see Chapter 2 of the County's Storm water Management Design Manual for Fee Schedules), the request will be logged in and a 2-week turnaround time is anticipated, unless there are extenuating circumstances or information is missing which precludes the study from being completed.

A County engineer will review the original request. In some cases, additional information may be required for the study to be completed. The County engineer will notify the applicant of any missing information. The existing or proposed stream crossing information necessary to complete the study is:

• Road profile;
• Minimum road elevations;
• Number of pipes;
• Pipe/culvert dimensions;
• Pipe material and type;
• Upstream and downstream maximum low chord elevations of each pipe;
• Upstream and downstream stream invert elevations of each pipe;
• Length of pipe/culvert;
• Number of piers;
• Pier shape;
• Width of piers;
• Headwall or wingwall type;
• Federal Highway Administration chart number for the culvert; and
• Federal Highway Administration scale number for the culvert.
  

The information provided must be surveyed and tied into existing County topography. In addition, if there is a proposed stream crossing, the location should be clearly shown in the plan view.

If the study involves a balance of cut and fill, the area of cut as well as fill must be clearly defined.

Once a study is complete, a report will be sent to the applicant with calculations, cross-section locations and floodplain elevations provided.

If the floodplain elevations are determined based on the County's GIS topography, a freeboard will be added. However, if the applicant provides more detailed topography, no freeboard will be added.

The floodplain will need to be delineated (by the applicant) on a detailed site plan and submitted to the Permits and Review Group of the Department of Environmental Resources for review and approval.

Note: Both FEMA and MDE will accept the County approved GIS-based floodplain.

Watershed Studies

Under Prince George's County Code Subtitle IV, Group 4, the Department of Environmental Resources has the responsibility to conduct watershed studies in order to:

1. Determine the magnitude and frequency of potential flood events based on existing conditions;
2. Determine the magnitude and frequency of potential flood events based on development that is planned for the future;
3. Define the possible alternative management techniques to control floods and minimize flood damage; and
4. Identify appropriate stormwater management strategies to alleviate the water quality impacts of land development and stream channel erosion and assist in the attainment and maintenance of water quality standards consistent with Federal, State and County programs and regulations.

The Stormwater Management Technical Group is an interagency technical group consisting of representatives from the Department of Environmental Resources and the Maryland-National Capital Park and Planning Commission, which has been formed to study watersheds in the County. Under the supervision of the Stormwater Management Technical Committee, the technical group has the responsibility of conducting technical studies that achieve the above mentioned goals. 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, wetland studies and the National Pollutant Discharge Eliminate System (NPDES) Program.

The evaluation of flood hazard mitigation alternatives includes the following:

1. Analysis of the runoff characteristics of both existing and planned development conditions in order to assess the impact of future land development and to aid in the development and evaluation of alternative land use patterns,
2. Flood insurance;
3. Flood proofing;
4. Elevation of structure;
5. Zoning and local land use regulations;
6. Flood warning systems;
7. Acquisition of flood prone structures;
8. Stormwater management;
9. Bridge and culvert improvement;
10. Channelization or channel modification;
11. Floodwalls;
12. Levees;
13. Retention/detention structures;
14. Stream relocation;
15. Stream enclosure; and
16. Combinations of the above.

The above alternatives are evaluated based on the following criteria:

1. Level of protection of mitigation provided;
2. Physical, legal and financial constraints;
3. Environmental impacts, including disturbance of wetlands, benefits to water quality, affect on aesthetics;
4. Public health and safety; and
5. State and Federal permit requirements.

A number of watershed studies have been completed and adopted by the County Council. These watershed studies are:

1. Tinkers Creek (adopted in September, 1980);
2. Western Branch (adopted in July, 1983);
3. Piscataway Creek (adopted in July, 1986); and
4. Henson Creek (adopted in July, 1986).

Other watersheds studies which have been completed are:

1. Folly Branch;
2. Bald Hill Branch;
3. Southwest Branch;
4. Collington Branch;
5. Charles Branch;
6. Oxon Run;
7. Anacostia River; and
8. Beaverdam Creek

Drainage Maintenance

Drainage Maintenance

The County Office of Highway Maintenance is responsible for a wide range of activities, part of which is pipe repair and replacement; ditch and channel maintenance; inlet and drainage pipe cleaning; stormwater management facility maintenance; and maintenance of various flood control facilities.

The following activities are specifically related to maintaining storm drainage and free flowing streams:

• Floodplain maintenance (cutting, mowing and weeding of various sites);
• Cleaning of streams and other stormwater maintenance sites (removal of debris, sediment and materials foreign to the natural vegetation);
• Application of herbicides along improved channels and within pumping stations to aid in vegetation management; and
• Cleaning County-owned and maintained earthen and concrete channels to remove obstructions, cut out heavy woody growth, and perform repairs.

Another important aspect of drainage maintenance is the inspection program. Each year more than 2,400 service requests are received from County residents. Inspectors respond within three working days, unless an emergency is reported, in which case the response is immediate. After high water events, especially if water overtops a road or bridge, an inspection is performed to determine if maintenance and repairs are warranted. A 24-hour emergency on-call program covers emergency service requests, and flood control and pumping station responses.

For questions regarding drainage maintenance, or to report a drainage problem, please contact the Office of Highway Maintenance Customer Service Office at (301) 499-8520. Further information can be found online at http://www.co.pg.md.us/Government/AgencyIndex/DPW&T/FAQ/storm_drainage.asp?nivel=foldmenu(2)

 Flood Control Facility Maintenance

In the 1940s, the U.S. Army Corps of Engineers constructed the Anacostia Flood Control Project. To manage drainage on the land-side of the levees, the Corps installed four pumping stations. The County operates and maintains the pumping stations, and in coordination with the Corps, conducts an annual inspection of the levees, floodway channel and pumping stations. The County is responsible for maintenance, including mowing, vegetation control, debris removal, and stabilization of erosion.

In addition to maintaining the Anacostia flood control project, the County owns, manages, and maintains several non-Federal flood control projects:

• Sligo Creek flood control levee, built by the Washington Suburban Sanitary Commission in 1973;.
• Northeast Branch flood and erosion control channelization (above East-West Highway), built by the Washington Suburban Sanitary Commission in 1976;
• Henson Creek flood control levee and channelization near Morningside, built by the Washington Suburban Sanitary Commission in 1972;
• Oxon Run flood control levee near Green Valley Drive, built by the Washington Suburban Sanitary Commission in 1982;
• Oxon Run tributary floodwall, built by the County to protect homes and a school (completed 2004); and the
• Northeast Branch flood control levee near Allison Street, built by the Washington Suburban Sanitary Commission.

Drainage Problems

One of the responsibilities of the Environmental Services Group (ESD) is to respond to citizen complaints regarding drainage problems. Drainage complaints range in nature from property flooding to home flooding and include such concerns as erosion and problems associated with sump pump discharges. Groundwater-associated problems are investigated with remedial actions suggested for homeowners, along with the provision of a residential drainage manual.

ESD investigates an average of 500 complaints per year, some of which evolve into corrective projects. Approximately 45 new drainage projects are initiated each year as a result of either homeowner complaints, referrals by other agencies, or requests by County Council Members.

If you are experiencing drainage problems, please call the Paul DeSousa at(301)883-5871 or (301) 883-5832 for assistance.

Public Outreach

As part of its overall floodplain management program, the County provides a number of services to local residents and businesses. These services include the following:

• Public assistance with inquiries about FEMA flood zones and floodplains generally;
• Proclamation from the County Executive and Council declaring June to be "Flood Awareness Month" with tips on flood safety and where to get additional information; airing of a local flood management video on County Cable; displays in public libraries on flood awareness, flood safety and related information;
• Flood Protection Library – Local libraries have information on flood mitigation and insurance (materials include local flood studies and contact information, as well as "generic" flood information materials from FEMA);
• The County publicizes the availability of floodplain information with lenders, realtors, insurance agents and the general public needing flood zone determinations for mortgage lending and insurance rating. In addition, information on floodplains generally, floodplain regulations, flood safety tips, natural and beneficial significance of floodplains and similar information is disseminated through a variety of outlets including: Stream Teams Workshops, county fair display, various public outreach events held throughout the year, library displays and holdings, press coverage in the local paper, county cable TV, and DER press release;
• Flood Warning Program - The County has a comprehensive Flood Warning Program for Western Branch and Anacostia River, which includes a state-of-the-art stream gauge network and flood warning system;
• Flood Protection Assistance - The County offers technical assistance to residents with drainage and flooding problems. In addition, a number of capital projects are undertaken to mitigate for potential flood events. Capital projects include acquisition of floodprone structures, floodproofing, and construction of drainage improvement projects;
• Development Review Activities – DER reviews development proposals to ensure compliance with relevant floodplain, stormwater management and grading ordinances to protect the health, safety and welfare of local residents and businesses; and
• Maintenance of Stormwater Management Facilities – All ponds and stormwater management facilities that are publicly owned, are maintained by the County's Department of Public Works & Transportation.

For more information about flood management, flood safety tips and flood insurance, contact Yanping Zhang at (301) 883-5787 or(301) 883-3311. For information on the National Flood Insurance Program, contact the Federal Emergency Management Agency (FEMA) at (800) 427-4661.

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Hurricane Season Special Warnings

Hurricane Season and Flood Awareness

The warm weather of summer brings with it the start of another change in weather commonly known as “hurricane season”. During this six-month period from June through November, the likelihood for hurricanes and tropical storms that impact the eastern United States is extremely high. While hurricane events in Prince George’s County are quite rare, the possibility of associated tropical storms, intense thunderstorms, and flood events are very real.

Residents and business owners located near a stream may wish to take measures to safeguard against potential losses associated with flooding. The Prince George’s County Department of Environmental Resources (DER) has a number of services available to assist local home and business owners with information about how to reduce the likelihood of flood losses. DER administers a comprehensive floodplain management program that includes: technical assistance to property owners with flooding and drainage problems, construction of capital projects to alleviate drainage and flooding problems (drainage systems, floodwalls, stormwater management ponds, levees), administration of a floodplain/stormwater management ordinance to prevent building in the floodplain and reduce the effects of development on “downstream” properties, dissemination of floodplain information to residents, businesses, lenders and insurance companies, and participation in the National Flood Insurance Program/Community Rating System which enables County residents to purchase flood insurance at a reduced rate.

A review of the floodplain studies prepared by FEMA and DER can determine if your property is located in or near the floodplain. Perhaps the single most important measure that owners of flood prone property can make is to purchase flood insurance. To obtain additional information on the location of your property as it relates to the floodplain, call Yanping Zhang at (301) 883-5787 or (301) 883-3311.  For more information on how to obtain flood insurance call the National Flood Insurance Program at (800) 427-4661.  Information on flood insurance, flood safety tips, flood and disaster preparedness can also be found on the FEMA website at www.fema.gov and at the Maryland Department of the Environment (MDE) website at http://www.mde.state.md.us/Programs/WaterPrograms/Flood_Hazard_Mitigation/reliefAssistance/index.asp.  Although flooding and other natural disasters can strike at any time, advance planning and preparedness will go a long way in reducing the impacts of a natural disaster.

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Disaster Do’s and Don’ts

Things you can do now to prepare for a flood event

• Educate yourself of the flood risks in your area;
• Find a fast and safe route to high ground from your home, place of work and school. Be aware of which transportation routes may be closed in case of flooding;
• Put together an emergency flood kit which should includes: a first aid kit with essential medicines, drinking water, a flashlight, batteries, non-perishable food, a portable radio, a can opener, blankets and warm clothing;
• Be sure to have temporary care lined up for your pets in case of flooding;
• Buy flood insurance; most homeowners’ policies do not cover flood damage;
• Store your valuables and toxic materials in higher areas of your house; and
• Create a list of the contents in your house complete with photographs. This will be useful for flood insurance claims and tax deductions following a flood event.

If time permits

• If there is sufficient time, protect your home with sandbags, plastic sheeting, and plywood. Remember sandbags should not be stacked against the building;
• Turn off all utilities; and
• Stock bathtubs and sinks with fresh water.

Things to do during a flood event

• Pay attention to the local weather forecast and flood warnings;
• Avoid flooded areas; DO NOT ATTEMPT TO WALK, SWIM OR DRIVE THROUGH A FLOODED AREA;
• If trapped in your home, move to the upper stories of the house and the roof if necessary. WAIT FOR HELP TO COME TO YOU;
• Stay away from electrical equipment in wet areas; and
• If your car is stuck in a flooded area, abandon your car as fast as possible to seek higher ground.

Things to do following a flood

• Do not use food, water and medicine contaminated by the flood waters;
• Do not use tap water until the community officials advise that it is safe;
• Be aware of hazards caused by structural damage to buildings;
• Turn off all utilities if you have not already done so. Do not use open flames when searching your home after a flood because of possible gas leaks;
• Electrical outlets and wiring need to be checked by a professional before usage. The No. 2 flood killer after drowning is electrocution;
• Dispose of contaminated carpeting and drywall;
• Be careful about drying wooden items in the sun because warping may occur;
• Do not pump out flood water from basements all at once. Pump out about one-third of the water per day;
• Document all flood loss for flood insurance, government assistance, and tax deduction purposes; and
• Pay attention to local news for information on any financial assistance available from FEMA. If access to the internet is available, use FEMAs website for up-to-date information on disaster assistance ( www.fema.gov ).

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Frequently Asked Questions (FAQs)

1. My mortgage company informed me that I am in a designated Special Flood Hazard Area (SFHA). What is a SFHA?
   
   The SFHA is what is commonly referred to as the "100-year" floodplain. This is somewhat of a misnomer because it often leads people to believe that this is a flood that occurs only once in 100 years when in fact there might be two "100-year" floods within a month. The "100-year flood" is the name given to a flood that has a 1% chance of occurring in any given year. In fact, over a 30-year mortgage, there is a 26% chance that a flood will occur to a home and only a 4% chance of a fire.

2. Why is my lender requiring the purchase of flood insurance?
   
   For nearly every mortgage transaction in the United States that involves a structure, the lender reviews current National Flood Insurance Program (NFIP) maps for the community in which the property is located. The NFIP map review is made to determine the location of the property in relation to the SFHA. If the lender determines that the structure is indeed located within the SFHA and the community is participating in the NFIP, the borrower is notified that flood insurance will be required as a condition of receiving a loan. These lender requirements are set forth in the Flood Disaster Protection Act of 1973 and the National Flood Insurance Reform Act of 1994. Stipulations of these legislative acts require the purchase of flood insurance by property owners who are being assisted by Federal programs or by Federally regulated institutions in the acquisition or improvement of land, or facilities, or structures located or to be located within an SFHA.

3. How can a property owner determine if the property is in a Special Flood Hazard Area (SFHA)?
   
   FEMA publishes Flood Insurance Rate Maps, which show the flood hazard areas in a community. The Flood Insurance Rate Maps are on file with the Department of Environmental Resources (DER) and many insurance companies. In addition to the Flood Insurance Rate Maps, DER has done a number of floodplain studies covering most of Prince George's County. The Flood Insurance Rate Maps and local floodplain study maps can be viewed by the public at the DER offices in Largo. In addition, local residents and business owners can call the Department of Public Works and Transportation at (301) 883-5777 to request floodplain information about their particular property.

4. What if I disagree with my lender's determination that I am in the flood zone?
   
   Property owners may not contest the requirement if the lending institution has established the requirement as part of its own standard lending practices. However, if a lending institution is requiring the insurance to meet mandatory flood insurance purchase requirements of the NFIP, the property owner and lender may jointly request that FEMA review the lending institution's determination. The FEMA review merely looks to see if the determination is accurate based upon a review of the NFIP maps and the location of the property in relation to the SFHA. If a property owner is not satisfied with the results of this review, they may apply for a Letter of Map Amendment (LOMA), which is a more detailed look at the elevation of the structure on the property and the elevation of the floodplain as shown on the NFIP map. Please call Yanping Zhang at (301) 883-5787 or (301) 883-3311 for additional information on the LOMA process.

5. Who can purchase a flood insurance policy?
   
   NFIP coverage is available to all owners or insurable property (a building and/or its contents) in a community participating in the NFIP. Owners and renters may insure their personal property against flood loss with "contents coverage".

For the answers to additional questions on flood insurance purchase requirements and flood zone determinations, visit the FEMA web site at http://www.fema.gov/business/nfip/ (This link opens in a new browser window).

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