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File #: 12-0016    Version: 1 Name: 2/21/12 - Revised Flood Map Adoption
Type: Ordinance Status: Passed
File created: 2/21/2012 In control: City Council
On agenda: 3/5/2012 Final action: 3/5/2012
Enactment date: 2/21/2012 Enactment #: ORD-12-02
Title: An Ordinance to Amend Section 8:101, to Add a New Section 8:105, and to Renumber Sections 8:105 through 8:121 of Chapter 100 - Construction Code - of Title V of the Code of the City of Ann Arbor (Ordinance No. ORD-12-02)
Attachments: 1. 12-02 Briefed and Approved, 2. ORD-12-02 Chapter 100 Briefed.pdf, 3. Chapter 100 Ordinance Amendment.pdf, 4. FEMA map mod LFD Oct 2011.PDF, 5. FEMA map adoption reminder Dec 2011.PDF, 6. Resolution to Manage Floodplain Development for the National Flood Insurance Program.PDF
Related files: 12-0199
Title
An Ordinance to Amend Section 8:101, to Add a New Section 8:105, and to Renumber Sections 8:105 through 8:121 of Chapter 100 - Construction Code - of Title V of the Code of the City of Ann Arbor (Ordinance No. ORD-12-02)
Memorandum
The City of Ann Arbor currently participates in the National Flood Insurance Program (NFIP). The NFIP makes flood insurance available within participating communities. Federal law requires flood insurance for any structure within the 1% annual chance floodplain (formerly known as the 100-year floodplain) that has a federally backed mortgage.

The date of the City of Ann Arbor’s current Flood Insurance Rate Map (FIRM) is January 2, 1992. In 2004, the Federal Emergency Management Agency (FEMA) began the process of revising the FIRMs for Washtenaw County. With assistance from the Michigan Department of Environmental Quality (MDEQ), complete restudies were performed for the main branch of the Allen Creek Drain, the West Park-Miller Drain (part of Allen Creek), the Millers Creek Drain, and the Swift Run Drain. Other floodplain areas of the City were remapped utilizing the previous flood models with updated data, such as more detailed contour information. On July 27, 2007, FEMA issued a preliminary Flood Insurance Study (FIS) and FIRM for Washtenaw County. FEMA went through a prescribed public review, appeal and revision period that was drawn out due to several map challenges in other portions of Washtenaw County. On October 3, 2011, FEMA issued a letter of final determination indicating that the new FIS and FIRM will become effective on April 3, 2012.

City Staff has analyzed the revised FIRM and compared it to the current (1992) FIRM. Since buildings are smaller than parcels, small adjustments to flood boundaries have a greater effect on buildings. Overall there is about an 18% reduction in the number of parcels affected by the floodplain, however there is a dramatic 43% reduction of the number of structures in the floodpl...

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