Flood hazard management in Vermont is a collaborative effort that includes federal, state and town governments, regional planning commissions (RPC’s), non-profit watershed organizations, and individual landowners.  The River Management Program (RMP) provides technical support and coordination for the implementation of flood hazard management programs throughout the State. 

The Floodplain Management section of the RMP works with the Federal Emergency Management Agency (FEMA) to oversee the National Flood Insurance Program (NFIP) in Vermont. The NFIP is a voluntary program administered at the community level.  Participating communities agree to manage floodplain development using building and land-use regulations. In return, residents have the ability to purchase flood insurance, apply for federally insured loans (such as mortgages), and receive flood disaster assistance. Most Vermont municipalities participate in the NFIP; to find out if your community participates visit FEMA's Community Status Book Report .  While NFIP designated floodplains provide a useful management tool, they do not necessarily show the full extent of flood risk along Vermont streams and rivers.  We encourage towns to be proactive in managing floodplains, and to adopt regulations that go beyond the minimum NFIP requirements. 

Fluvial Erosion Hazard (FEH) mitigation is another flood hazard management tool used by the River Management Program.  Fluvial erosion can range from gradual bank erosion to catastrophic changes in channel location and dimension during flood events.  Fluvial erosion is the cause of a vast amount of flood damage in Vermont, but is not taken into account by NFIP maps.  The FEH program works to map the extent of the floodplain susceptible to fluvial erosion and works with municipalities on limiting development in these sensitive areas.  Adoption of FEH maps provides another tool for Vermont communities to determine flood risk, minimize flood losses, and protect our water resources.  The River Management Program encourages Vermont communities to manage their floodplains based on both inundation and fluvial erosion hazards.

Floodplain Management through the NFIP

The NFIP floodplain maps represent an estimate of the risk of flooding due to inundation of rising water from a river or lake.  These maps specifically show the extent of the floodplain affected by the base flood.  This is the severity of flood that has a 1% chance of occurring in any given year, and the base floodplain is called the Special Flood Hazard Area (SFHA).  The SFHA is often divided into two areas, the floodway and the flood fringe.  The floodway is the area near the stream channel where water moves the fastest during a flood event and poses the greatest danger.  The floodway must be kept free of development to prevent a rise in floodwater throughout the community.  The flood fringe represents the rest of the area between the floodway and the SFHA boundary.  Development in the flood fringe is regulated by the local government; you can check your community's flood hazard ordinance to see these restrictions.  You can view the effective NFIP maps for your community at your town office, or online at the FEMA Map Service Center.

All areas in a community are susceptible to flooding, although to varying degrees.  If your home is located in the SFHA, it has a 26% chance of being damaged by a flood over the course of a 30-year mortgage.  Homes outside the SFHA may also have a substantial risk of flood damage.  In fact, 25% of all flood claims occur in the low-to-moderate risk areas.  Flood insurance is available to any property owner or renter in a community participating in the NFIP. 

Here are a number of resources available from the RMP and FEMA to help understand the NFIP and development regulations in the SFHA:

• Homeowners and Property Owner FAQs  (pdf, 57kb)
• Municipalities and Floodplain Managers FAQs (pdf, 66kb)
• NFIP minimum regulations (pdf, 67kb) - Flood inundation and erosion hazard regulations from 44 CFR §60.3 and §60.5.
• NFIP definitions (pdf, 85kb)
• FEMA Publications
  • Floodplain Management Publications (pdf, 61kb) - Answers to questions about the NFIP, protecting utilities, understanding floodplain maps, retrofitting homes, administering NFIP regulations, etc
  • Technical Bulletins (pdf, 51kb) - Resources designed to aid in buidling design and construction in flood prone areas
  • Forms (pdf, 50kb) - Letter of Map Amendment (LOMA) forms, Flood proofing and Elevation Certificates, Application for Community Enrollment in the NFIP
  • Brochures (under construction) - Short informational resources that can be distributed to community member

Flood Hazard Maps

Maps of the flood hazard areas in your community can be viewed at your municipal office.  The maps are also available in paper and pdf format through the FEMA Map Service Center and can be viewed and printed online at msc.fema.gov or ordered from 800.358.9616.

Updates to the flood hazard maps are now underway in Washington and Chittenden Counties as part of the FEMA Map Modernization Program.  New Digital Flood Insurance Rate Maps (DFIRM) for Rutland, Windham, and Windsor Counties are now available as paper maps, pdf documents, and as GIS data, by county.

Update on Washington and Chittenden County Flood Hazard Map process - 9/1/2009  PDF

At this time, the following counties are not currently scheduled for map updates: Addison, Caledonia, Essex, Franklin, Grand Isle, Lamoille, Orange, and Orleans. VT DEC is working with FEMA to get the maps of the remaining nine counties updated.  Beginning in October 2009 FEMA will begin a transition to a new mapping update effort entitled “RiskMAP” (Risk Mapping Assessment and Planning).  In the coming year it is anticipated that FEMA will prepare a Task Order for map work in Bennington County.

In Washington County, the Preliminary DFIRM was released in May 2007.  The Washington County work included new hydrological and hydraulic studies on the Winooski River, Stevens Branch, and Gunners Brook.   VT DEC raised concerns with the hydrological study method used by the contractor. The Final Community Meetings for Washington County were held in July 2007 immediately after flash flooding in Washington County.  VT DEC and local officials noted that on Gunners Brook the flood event was on the order of a 25 year return frequency, but some of the flooding extended well beyond the boundaries of the 100 year return boundaries of the SFHA.  In March 2008 FEMA Region One agreed to correct the hydrology used in the study.  In June FEMA informed VT DEC that an upcoming FEMA contract with CDM would fund the work to improve the hydrology.  The specific revised Preliminary DFIRM panels for Washington County were released 6/15/09 to the appropriate communities.  The Washington County Revisions include new hydrology on Stevens Branch; new hydraulics and delineations along the Winooski River downstream from the Middlesex Dam #2; stillwater base flood elevations for Mirror Lake and East Montpelier Pond; and refinements to A Zone boundaries in Cabot, Calais, East Montpelier, Marshfield, Plainfield, and Worcester.   For more information, please see the “Update” document above. 

The Chittenden County Preliminary DFIRM for was released on July 10, 2009.  The DFIRM includes new hydraulics along the Winooski River downstream to the Essex Dam #19 and redelineation below that point using contours with two foot intervals.  Browns River received detailed study including topography, hydrology, and hydraulics.  For more information, please see the “Update” document above. 

For more information on the Flood Hazard Map Modernization process in Vermont, or for help with data, community bylaws, or insurance grandfathering opportunities please contact Ned Swanberg at 802.241.4596 or ned.swanberg@state.vt.us

FEMA Map Service Center msc.fema.gov  800.358.9616  The MSC has current / effective and historical flood hazard maps, floodway maps, flood insurance studies, letters of map change, and many other resources.  Most of these are available on line.

Regulating Development in Vermont floodplains

The River Management Program recognizes that the best way to maintain healthy rivers and floodplains, as well as protect public safety, infrastructure and property, is to discourage development in NFIP floodplains and FEH corridors.  The RMP helps to reduce flood risk by providing technical assistance to communities regulating floodplain development.  Our office can provide general assistance and education about flood hazards and floodplain regulations, including the NFIP and Fluvial Erosion Hazards.  Two of the primary ways we help communities regulate floodplain development are by reviewing municipal floodplain development permits and by assisting towns in developing community floodplain regulations.

Flood Hazard Area Regulations – To enable residents to acquire flood insurance, your community must participate in the National Flood Insurance Program (NFIP) and regulate development in the Special Flood Hazard Area.   The regulations must meet or exceed the requirements of the NFIP.  Vermont DEC has prepared model flood hazard regulations as posted below.  These models meet or exceed the requirements of the NFIP as provided for under Vermont law in Title 24 VSA Chapter 117.  When your community is updating your flood hazard regulations your Planning Commission should start with a current model and then work with your Regional Planning Commission or other consultants as appropriate.  When your PC has prepared a draft, please send it to the Vermont DEC Floodplain Management Program for review.   Comments will be returned within 30 days.

Many Vermont communities have structures built in the flood hazard area.  To address this situation the community has a Hazard Mitigation Plan that informs the town plan, as well as local land use regulations to implement that plan.  Inundation and erosion caused by flooding cause the largest annual disaster costs in Vermont.   Additionally, in some towns, roads, bridges and critical facilities including emergency response centers are located in or near the flood hazard area.   The risk of damage to structures in the flood hazard area may increase as development occurs in the watershed, and as the Vermont climate changes.

The FEMA Flood Insurance Rate Maps (FIRM) identify areas vulnerable to inundation during the base flood (the one percent annual chance flood).  A structure in the flood hazard area has more than a one in four chance of getting flooded during a 30-year mortgage.  The FIRM does not identify flooding risk due to dam breaks, most ice-jam flooding situations, nor areas (and public infrastructure) vulnerable to erosion caused by flooding.    VT DEC has developed maps of Fluvial Erosion Hazard Zones for many municipalities, and recommends that Vermont municipalities regulate development and prohibit new structures in these zones.   

The table below briefly describes four models and includes links to pdf versions of the texts. 

• Model 2 is appropriate for a municipality that does not have zoning and does not have access to Fluvial Erosion Hazard Maps.    Model 2 includes administrative text and can be adopted under Chapter 117 §4411 and/or §4424.
• Models 3 and 4 are appropriate for municipalities that have existing zoning and Fluvial Erosion Hazard Zone maps.  Model 3 assumes that the municipality has little current exposure to flood hazards, adequate flood emergency response capacity, and permits new structures outside of the Fluvial Erosion Hazard Zone where such structures are elevated and accessible by dry land.
• Model 4 clearly prohibits new structures in the Special Flood Hazard Area and the Fluvial Erosion Hazard Zone, and is less complex to administer.
• Model 5 is for communities with zoning that do not have access to Fluvial Erosion Hazard Zone maps.

• Community Rating System (CRS) – Communities with a large number of structures already in the flood hazard zone may benefit from participation in the FEMA CRS program.  The CRS program provides a discount on premiums to flood insurance policy holders in towns that choose to participate.  Model Regulations 3 and 4 provide substantial rating points.  Additional points to quality are available for public outreach efforts, storm water maintenance, and other actions.  Currently Brattleboro, Bennington, and Montpelier participate in the CRS program.  For more information, contact VT DEC.

Development Reviews - The NFIP defines development as the placement of fill, construction, dredging, drilling, grading, excavating, mining, and the storage of materials.  NFIP regulations (44 CFR §60.3) require that a municipal permit be obtained for any development in a FEMA mapped floodplain.  Vermont law (24 VSA §4424) requires that all municipal permit applications for floodplain development be sent to the River Management Program for a review and comment.  The NFIP regulations can be complex, and this statute allows the RMP to ensure that floodplain development is compliant with the NFIP and FEH regulations in the community's ordinance.  Our office can work with zoning officials and developers to suggest development alternatives to mitigate flood risk.  Permit applications for floodplain development can be sent to the email or address below.  Please call the office if you have any questions about this procedure.

• Floodplain Permitting Flow Chart (under construction) - A detailed chart explaining different circumstances involved in floodplain development and the information needed from the applicant to ensure a timely development review.
• Development Review Submission Checklist (pdf, 101kb) - A full list of the materials necessary for the River Management Program to review municipal permit applications.

Additional Resources

We have compiled several resources, documents and organizations that can help provide further information on floodplain management:

• ANR - Water Quality Division and River Management Program resources:
  • CONTACT SHEET (under construction)- Information on State, regional and federal partners that can be downloaded and posted in your Town offices.
  • Obtaining a LOMA in Zone A (78kb) - explains all of the surveying and application requirements for obtaining a Letter of Map Amendment in an approximate "A Zone"
  • River Corridor Protection and Management factsheet (pdf, 205kb) - An overview of river dynamics, flooding, and floodplain protection in Vermont
  • Defining River Corridors factsheet (pdf, 176 KB)
  • Options for State Flood Control Policies and a Flood Control Program, Act 137 (pdf, 1mb)
  • What Your Town Needs To Know About the National Flood Insurance Program - PowerPoint presentation providing an overview of floodplain management principles and the NFIP
  • Mitigating Flood-Related Fluvial Erosion Hazards (FEH) Using River Corridor Protection Fact Sheet (pdf, 194 KB)
    
    

• Act 250 Floodway Guidance (Criterion 1D):
• Procedure on ANR Floodway Determinations in Act 250 Proceedings (pdf, 161kb)

• Technical Guidance for Determining Floodway Limits Pursuant to Act 250 Criterion 1 (D)

• Floodway Guidance Transmittal Letter

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• FEMA floodway regulations and technical guidance:
  • No Rise Certification (pdf, 28kb) - Guidance and sample form for use by engineers to provide certification that engineering analyses show no rise in community flood waters as a result of floodway development.
  • Numerical Models - Link to information on acceptable models used by FEMA in floodway analyses.

• Association of State Floodplain Managers - an organization involved in floodplain management, flood hazard mitigation, and flood preparedness, warning and recovery.  ASFPM recommends a “no adverse impact” approach floodplain management to help control spiraling flood and erosion losses, new development which increases flood risks, and then additional flood losses. With such an approach, future land and water uses are not permitted which will flood new areas, increase flood heights, increase erosion or otherwise increase flood and erosion damages to public and private property. The "no adverse impact" approach has been suggested as a general guide for landowner and community actions in the watersheds and the floodplains which may adversely impact other properties or communities.
  • Government Liability and No Adverse Impact Floodplain Management (pdf, 115kb)
  • No Adverse Impact and the Courts: Protecting the Property Rights of All (pdf, 2.5mb)
  • Professional Liability for Construction in Flood Hazard Areas (pdf, 237kb)
  • Property Rights and Community Liability (pdf, 156kb) - No Adverse Impact fact sheet on the legal framework for managing watershed development

• Two Rivers-Ottauquechee Regional Commission devotes a section of their web site to water quality, including floodplain management, erosional hazards, and river corridor planning.  They have developed the following educational fact sheets on floodplain management (in cooperation with the River Management Program and the Vermont Law School):
  • 1 - Floodplain Basics (pdf, 459kb)
  • 2 - Protecting Property Rights to Reduce Liability (pdf, 570kb)
  • 3 - Living with Inadequate Maps (pdf, 1.6mb)
  • 4 - Using Freeboard and Setbacks to Reduce Damage (pdf, 1.8mb)
  • 5 - No Adverse Impact Floodplain Management (pdf, 451kb)
  • 6 - Protecting Lives and Property Through the NFIP Community Rating System (pdf, 404kb)

Additional Information

If you have general questions regarding mandatory flood insurance purchase requirements or obtaining Letters of Map Change from FEMA please visit the FEMA Map Assistance Center, or contact a FEMA Map Specialist at:

FEMAMapSpecialist@mapmodteam.com or 1-877-FEMA-MAP (1-877-336-2627).

For questions regarding Vermont floodplain management, including regulatory requirements for projects in the floodplain, please contact:

ANR.Floodplains@state.vt.us or 1-802-241-3759.

Municipal permit applications for flood hazard area development can be sent to:

Rob Evans, VT State Floodplain Coordinator, DEC Water Quality Division, 103 South Main Street Building 10N, Waterbury, VT 05671

To learn more about the Fluvial Erosion Hazard Program, please contact Kari Dolan, FEH Coordinator, at:

Kari.Dolan@state.vt.us or 1-802-241-1262.  Municipal Guide to Fluvial Erosion Hazard Mitigation  (pdf, 867 KB)

 

Updated: March 19, 2008