ASFPM Riverine Erosion Hazard 2016 White Paper

Over the past 15 months, Mike Kline and Rebecca Pfeiffer from our Vermont Rivers Program have been working on a riverine erosion paper with other practitioners from across the country.  The paper was recently presented to the executive committee of the Association of State Floodplain Managers (ASFPM) as a Discussion Paper.  The Executive Committee thought it was so well done and connected with the paper's recommendations that they decided to adopt it as ASFPM Policy in the form of a White Paper.  You can read more about the paper here, or link directly to it from here:

http://www.floods.org/ace-images/ASFPMRiverineErosionWhitePaperFeb2016.pdf

New Maps in Bennington County!

The long-anticipated Bennington County Digital Flood Insurance Rate Map became effective 12/2/2015.  The data can now be found online at:

• FEMA Map Service Center www.msc.fema.gov 
• Flood Ready Atlas tinyurl.com/floodreadyatlas (Html 5); 
• Vermont Natural Resource Atlas tinyurl.com/vt-floodmap  (Silverlight).

The FEMA Map Service Center allows users to search by address and find the effective and historic flood maps for any location.  The MSC also has the Flood Insurance Study and Letters of Map Amendment.  Outside of the areas with Digital Flood Insurance Rate Maps the MSC has scanned copies of the “white/paper” FIRMs.

The Vermont Natural Resource Atlas has two online platforms.  The Html 5 version can be used by all computers and browsers.  The Silverlight version requires Internet Explorer and a PC that can load the Microsoft Silverlight software (a fairly quick process).

Where there are DFIRMs available, the MSC allows users to download GIS versions of the Special Flood Hazard Areas and other vector data.

The Vermont Center for Geographic Information will also post the GIS data later this month.

On the Flood Ready Atlas you can find a specialized layer for Flood Hazard Mapping that shows areas of Vermont with effective DFIRMs.

With the process in Bennington County completed no other flood map updates are scheduled by FEMA in Vermont.  This leaves large areas of the state with old maps needing attention.  Any future map work by FEMA will be handled through the RiskMAP approach.  RiskMAP uses a HUC-8 watershed boundary as the basis of map updates.  This would be the equivalent of the Missisquoi or Passumpsic River watersheds.

Flood Inundation Maps & Report Released for Lake Champlain & Richelieu River

In the last post, information was provided about the draft report prepared by a working group of the International Joint Commission (IJC) about flood inundation and forecasting in the Lake Champlain-Richelieu River watershed.  The IJC is a a collaboration between the US and Canada to provide coordination, management and protection of shared watersheds. Here in Vermont, we have representatives that have been appointed to the International Lake Champlain-Richelieu River Technical Working Group.

Today, the final report that came out of the Lake Champlain-Richelieu River Technical Working Group was released.  The report, A real-time flood forecasting and flood inundation mapping system for the Lake Champlain-Richelieu River watershed, was an outcome of a 2013 comprehensive Plan of Study.

From the press release:

"The IJC endorses the TWG observation that enhanced coordination among agencies involved in real-time forecasts is necessary to support the development and maintenance of forecast models and quality-controlled joint water level predictions. The Commission endorses the TWG recommendation that a binational coordination body be mandated and funded to consolidate and synthesize flood forecasting work undertaken domestically into a single binational flood forecast. This body would also be charged with developing and disseminating consistent messaging to emergency responders and the public.

"Consequently, the new IJC report does not evaluate potential flood mitigation measures as this was outside the terms of reference provided by governments.

"The Commission reiterates its strong recommendation that governments implement the full scope of the 2013 Plan of Study (PoS) to evaluate past impacts, flood plain management practices and adaptation strategies, and to assess soft (i.e., low impact and cost) to moderate flood mitigation measures and their impacts."

An outcome of the report was a series of inundation flood maps that show the areas of the Lake Champlain and Richelieu River shorelines that would be inundated when the Lake flood waters are at a certain height. Again, from the press release:

"The inundation maps show flooding potential under different flood scenarios and are not designed for regulatory purposes. A preview of these maps is available on the IJC web site at: http://arcg.is/1MhXui2."

Please take some time to explore the inundation maps, as well as read through the final report which can be found at http://ijc.org/files/publications/Lake-Champlain-IJC-Report-to-Govts-Dec-2015-NEW.pdf 

IJC invites public comment on draft flood forecasting and mapping report for Lake Champlain and Richelieu River

IJC invites public comment on draft flood forecasting and mapping report for Lake Champlain and Richelieu River and previews flood inundation maps

The International Joint Commission (IJC) is requesting comments from the public on a draft report to enhance flood preparedness and warnings for Lake Champlain and the Richelieu River by December 10, 2015.  Specifically the IJC asks if the report’s recommendations are sound and whether the recommendations address real needs for enhanced flood preparedness and warnings for Lake Champlain and the Richelieu River.  The Commission is also inviting the public to preview the associated flood inundation maps.

Following the submission of IJC’s  July 2013 Plan of Study “The Identification of Measures to Mitigate Flooding and the Impacts of Flooding of Lake Champlain and Richelieu River” (POS), the governments of the United States and Canada asked the IJC to address two issues associated with the system wide flooding in 2011:
a. closing the gaps in the data needed for a future real-time flood forecasting and inundation mapping system, and
b. the creation of static flood inundation map products.

The IJC appointed the International Lake Champlain-Richelieu River Technical Working Group (TWG) comprised of technical experts from United States, Canada, Quebec, Vermont, and New York to address the two issues. The IJC is now inviting public comment on the TWG’s draft report Toward an operational real-time flood forecasting and flood inundation mapping system for the Lake Champlain and Richelieu River.

The TWG report includes six recommendations addressing the need to:

1. Implement an operational probabilistic approach for forecasting floods, including modelling of wind set up and wave action;
2. Keep the Henry and Grand Isle water level station to maintain water level calibration and also install wave buoys to assist in wave model calibration;
3. Institute a binational coordination body such as an IJC Board to support agencies involved in real time forecasting;
4. Acquire new bathymetric data for the Richelieu River between Sorel and Saint-Jean-sur-Richelieu;
5. Create a single consistent Digital Elevation Model (DEM) for the entire Lake Champlain-Richelieu River basin following the completion and quality control of LiDAR and bathymetric data acquisition; and
6. Generate static flood inundation maps for the entire Lake Champlain Richelieu River system.

The current effort has significantly advanced the creation of flood-inundation maps for the Lake Champlain-Richelieu River system. These maps provide an emergency planning tool for authorities and the general public on land that may flood during high water events. Static inundation maps were created for the Vermont side of Lake Champlain and a portion of the New York northeastern shoreline on the US side, and for the Richelieu River from the border to downstream of the Fryers Rapids on the Canadian side. A preview of these maps is available on the IJC web site at: http://arcg.is/1MhXui2 , however, the site is under construction and the text accompanying the maps is in French only at this time. A complete LiDAR Digital Elevation Model available in Canada also allowed for the representation of inundation depths for the 11 flood scenarios.  The inundation maps are not designed for regulatory purposes, but rather to show flooding potential under different conditions.  Furthermore the report does not evaluate potential flood mitigation measures as this was outside of the scope of the reference from governments.

This public comment period is being held from November 16 to December 10, at which time the IJC will consider public comments before submitting its final report to governments.


Contacts:

Nick Heisler  (English)  Ottawa 613-992-8367 Heislern@ottawa.ijc.org

Sarah Lobrichon (French)      Ottawa 613-992-5368 LobrichonS@ottawa.ijc.org

Frank Bevacqua Washington 202-736-9024 Bevacquaf@washington.ijc.org

                                             
Sarah Lobrichon
Policy and Communications Analyst | Analyste des politiques et des communications
International Joint Commission | Commission mixte internationale
234 Laurier Ave. West, 22nd Floor, Ottawa, Ontario, Canada K1P 6K6
234, avenue Laurier Ouest, 22e étage, Ottawa (Ontario), Canada K1P 6K6
Telephone | Téléphone 613-992-5368 / Facsimile | Télécopieur 613-993-5583

Imagine two countries sharing hundreds of lakes and rivers along their border without conflict
www.ijc.org
Imaginez deux pays qui partagent des centaines de lacs et de rivières le long de la frontière sans conflit

Live in Bennington County? - Check the New Flood Map !

On December 2, 2015 the new Digital Flood Insurance Rate Map will go into effect covering Bennington County, Vermont.  If you live in or near a floodplain you should check the map to see what level of risk has been identified for your building.

The Special Flood Hazard Areas (Zone A and AE) on the new Digital Flood Insurance Rate Map (DFIRM) can be viewed on the Flood Ready Atlas tinyurl.com/floodreadyatlas.   Choose "Flood Ready Tools" then "Zoom to Address" and "Toggle Flood Data On".

Special Flood Hazard Areas include areas with a 1% annual chance of flooding.  This is more than a 1 in 4 chance over the period of a 30 year mortgage.  Some parts of the mapped floodplain get flooded more frequently and are subject to high velocity flows.

The current FIRMs (made town by town) will expire in December.  They can be viewed online (as .pdfs) at the FEMA Map Service Center www.msc.fema.gov   You can make a small official FIRMette map and plot the location of your building from mapped road intersections.

Check the maps to determine if your building is at risk of damage from the base flood.   Federal law requires lenders to ensure that any mortgages or loans to buildings in the high risk SFHA have insurance to at least cover the mortgage, the value of the building, or the total amount available from the National Flood Insurance Program (whichever is lowest).

If your building was built before the first municipal Flood Insurance Rate Map (late 1970's), and your structure will become identified as being at high risk for the first time, you should learn about "grandfathering your flood zone".  To grandfather your flood zone you would need to buy a flood insurance policy before the map change and then maintain the policy going forward.  This would give you an opportunity to grandfather the lower risk / lower cost Zone X status on the basis of "continuity of coverage".

There will be public meetings in the fall to discuss flood insurance, grandfathering, and how to make buildings less vulnerable to damage and less costly to insure.

Bennington County has over 600 families as well as educational, government and critical facilities in the high risk flood zone.

Across the county (and the state) the Town of Bennington has the most structures in the Special Flood Hazard Area, around 480 (8% of all buildings in town).

Overall there seem to be around 450 buildings that may be indicated as in the high risk flood hazard area (Zone A, AE, AO) for the first time.  Approximately 350 have been newly identified as in the low to moderate risk Zone X.

The towns with the most structures that have been newly identified as at high risk include Bennington, Pownal, Arlington, Manchester and Dorset.

Watch for updates regarding insurance meetings in the fall.