Flood Map Modernization in North Dakota North Dakota State Water Commission FLOOD MAP MODERNIZATION.

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Transcript of Flood Map Modernization in North Dakota North Dakota State Water Commission FLOOD MAP MODERNIZATION.

Flood Map Modernizationin North Dakota

North Dakota State Water Commission

FLOOD MAP MODERNIZATION

Flood Map ModernizationFlood Map Modernization

Nationwide, 5-year, $1 billion program to update FEMA’s Flood Insurance Rate Maps (FIRMs) and convert them to a countywide, digital format (DFIRM) that will be available through the internet

Existing paper FIRMs may no longer reflect current flood risks (due to changes in drainage patterns resulting from erosion, land use practices, development, etc.)

Goal: digital flood map products will be available for 92% of the Nation’s population and will cover 65% of the land area of the continental US

Integrate local participation into the mapping process

NDSWC - “Cooperating Technical Partner” since 2004

Flood Map ModernizationFlood Map Modernization

New maps will allow for better decision-making by key stakeholders

Builders and developers

Community officials and planners

Real estate agents and lenders

Insurance agents

Business owners

Homeowners and renters

COMPONENTS OF A DFIRM

Flood Map ModernizationLifecycle of a DFIRM Project

24-36 months

Source: FEMA

Flood Map ModernizationMapping Process & Timeline

Flood Map ModernizationLocal Needs Identified

Existing Data• FIRM panels, FIS• LOMC• Existing data studies• Levee information• Base Map: orthophotos, elevations, roads & railroads, hydrography, political

boundaries, etc.

Does technical information meet FEMA Data Standards?

Local Mapping Needs• Areas for restudy• Problem areas • Unmapped areas where development is occurring

Flood Map ModernizationMapping Process & Timeline

Production Methods

• Digitization

• Redelineation

• Approximate Analysis

• Detailed Analysis

Flood Map ModernizationData Development

Digitization

If available, use existing workmap instead of FIRM

Existing floodplain boundary is lifted from existing map

Clean up spots where paper map does not match base map

Flood Map ModernizationData Development

Redelineation Digitize cross sections Extract elevations of flood using effective profile No change in flood elevation, but better flood

delineation Redelineation accuracy dependent on accuracy of

available topo

Flood Map ModernizationData Development

Flood Map ModernizationData Development

Detailed Analysis

Channel geometry surveyed

BFEs printed on the map

Floodway defined

Most expensive

Flood Map ModernizationMapping Process & Timeline

Flood Map ModernizationLocal Participation - Today

Identify Mapping Needs•Areas for re-study•Problem areas•Unmapped high development areas

Existing Data Studies (Corps, NRCS, etc.)

Leverage (Goal: 80% Federal, 20% Local)•Digital Data•Funds

Levees

Flood Map ModernizationLocal Participation - Future

Review preliminary products

Collect and submit Appeals/Protests

Final map adoption

Flood Map ModernizationCommunity Adoption Process

Preliminary maps distributed, 30-day comment period begins

Public “Community Coordination” meeting held

BFE changes published in Federal Register

90-day appeal period begins, submitted to and resolved by FEMA

FEMA issues “Letter of Final Determination”

FIS and Map submitted for printing

Map/FIS become effective 6 months from LFD issuance

Community is given 6 months from effective date to enact the required ordinances or may be suspended from the NFIP

Countywide Map Modernization Projects

NDSWC & FEMA

Thanks for your participation!

For more information, please visit these sites:

general info http://www.fema.gov

NFIP http://www.floodsmart.gov

map mod http://www.fema.gov/plan/prevent/fhm

map service center http://msc.fema.gov

datums http://www.ngs.noaa.gov