Floodplains and your Treatment Plant

How Hurricane Katrina Is Changing Your Floodplain in Michigan

Daniel Schechter, P.E.Greeley and Hansen

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August 30, 2005 – New Orleans, LA. Aerial view of some of the damage the day after Hurricane Katrina hurricane hit August 29, 2005. This is the levee on the east or lower side of the Industrial Canal. Photo by Jocelyn Augustino/FEMA

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What Does Hurricane Katrina Have To Do With My Facility?

As a Result of Hurricane Katrina,

1.FEMA is modifying, digitizing nearly all floodplain maps over 2008 – 2015

2. Increased attention to construction in floodplains

3.Levees and flood control structures are requiring inspection

4.Some levees and flood control structures are being decertified

Importance of Floodplains

100-yr and 500-yr floodplains affect what structures can be built on site and how they are protected

Will affect flood insurance requirements for residents, business, municipalities

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Construction Permit Application

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Classifications

1. Facility in the 100yr Floodplain2. Facility in the 100yr Floodplain

Protected by Floodwall / Dike / Fill / etc.

3. Facility not in the 100yr Floodplain

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Facility in a Floodplain

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Facility In the 100yr Floodplain - Protected

Proposed Floodwall

Facility in the 100yr Floodplain?

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Is it the borders on the FEMA map?

Is it anywhere on the site at or below the flood elevation?

Is it the area that would be inundated by a flood?

Possible Consequences Wastewater outfall needed to be re-

designed because structure determined to be in floodplain

State now requiring floodplain permit for construction activities at site where previously not required by state

Detailed floodplain study required before construction can be permitted at site

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Possible Consequences, cont’d Portion of site no longer buildable Buildings with “substantial improvement”

will need flood protection Need to submit Letter of Map Revision

(LOMR) to FEMA Delays associated with obtaining permits,

conducting studies

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Who Is In Charge? Local Government MI Department of Natural Resources and

Environment (DNRE) Federal Emergency Management Agency

(FEMA) US Army Corps of Engineers (USACE)

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Flood Insurance Rate Maps (FIRM)

What year were they issued? What revisions have been made? When will they be updated? How can I submit data for the next

revision? What datum is used?

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Flood Insurance Rate Map (FIRM)

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Digital FIRM Viewer

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FEMA Mapping Updates

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General Flood Standards Protective structures need to be 3 feet

above 100 year floodplain elevation “New” structures need to be outside of

floodplain Flood protection for structures in

floodplain “Critical” structures outside of 500yr

floodplain Wide variation in application

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Possible Endpoints Floodplain Permit (MDNRE / ACOE Joint

Permit) Floodproofing of Structures Letter of Map Amendment (LOMA) Letter of Map Revision (LOMR)

Investigate Ahead of Time!!

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Important Resources

MI DNRE Floodplain Managementwww.michigan.gov/deq

FEMA Map Service Center www.fema.gov

U.S. Army Corps of Engineerswww.lre.usace.army.mil

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Questions?

Daniel Schechter, P.E.Greeley and Hansen211 W Fort St., Suite 710Detroit MI 48226Tel (313) 628‐0730Email: dschechter@greeley‐hansen.com

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