Ann Arbor, Michigan Flood Zones
Ann Arbor faces flooding from the Huron River and its tributaries. Urban development around the University of Michigan has increased impervious surfaces and stormwater runoff.
FEMA Flood Risk Profile: Washtenaw County
Based on FEMA's National Risk Index, which evaluates flood risk at the county level using historical loss data, exposure, and vulnerability.
Inland Flood Risk
Relatively ModerateEst. annual loss: $46.6M
Hurricane Risk
Very LowEst. annual loss: $73K
Source: FEMA National Risk Index, county-level assessment. Individual property risk may vary.
Federal Flood Disaster History: Washtenaw County
Washtenaw County has been included in 2 federal flood-related disaster declarations.
These declarations affected communities across Washtenaw County, including Ann Arbor.
Source: OpenFEMA Disaster Declarations Summaries API. Data sourced February 2026.
NFIP Flood Insurance Claims: Washtenaw County
Properties in Washtenaw County have filed 132 NFIP flood insurance claims totaling $1.6M in payouts since 1978. The average claim payout is $12K.
Highest-Claim Years
2011
19 claims - $228K
2010
14 claims - $80K
2001
13 claims - $121K
Claims by Flood Zone
Zone AE
77
Zone X
39
Zone A
10
Source: OpenFEMA NFIP Claims API. Data sourced February 2026.
Common Flood Zones in Ann Arbor
Properties in Ann Arbor, MI are commonly designated in these FEMA flood zones:
What Your Flood Zone Means in Ann Arbor
Ann Arbor faces flood risk primarily from river and stream overflow during heavy rainfall, snowmelt, or upstream dam releases. When rivers exceed their banks, floodwaters spread across low-lying areas mapped in AE and A zones. The most common FEMA flood zone designations in Ann Arbor are Zone AE, Zone X. FEMA's National Risk Index estimates the county's annual expected loss from inland flooding at over $46.6M.
Riverine flood risk in Ann Arbor is driven by the proximity and elevation of properties relative to nearby waterways. Properties closer to rivers with lower ground elevations typically face higher flood insurance premiums under FEMA's Risk Rating 2.0. If your property is in a Special Flood Hazard Area (SFHA) and you have a federally regulated or government-backed mortgage, federal law generally requires your lender to ensure you carry flood insurance.
River flood maps can change when FEMA conducts new Flood Insurance Studies or when development alters drainage patterns. Letters of Map Amendment (LOMA) can remove individual properties if the natural ground elevation was always above the Base Flood Elevation and the property was inadvertently mapped in the SFHA. Use our free lookup tool to check the current flood zone for any Ann Arbor address.
Flood Insurance Discount: Ann Arbor
Ann Arbor participates in FEMA's Community Rating System (CRS), a voluntary program that rewards communities for flood mitigation efforts beyond minimum NFIP requirements. Residents in the Special Flood Hazard Area may qualify for reduced flood insurance premiums.
CRS Class
Class 6
SFHA Premium Discount
20% off
CRS classes range from 1 (best) to 10 (no discount). Ann Arbor's Class 6 rating means NFIP policyholders in the SFHA can receive up to a 20% discount on their flood insurance premiums. Properties outside the SFHA may receive a 10% discount.
Source: FEMA Community Rating System, October 2025. Discounts apply to NFIP policies only.
Check Your Ann Arbor Address
Enter any Ann Arbor, MI address to instantly see its FEMA flood zone, risk level, and whether flood insurance is required.
Free Flood Zone LookupAnn Arbor, MI Flood Zone FAQ
What flood zones are in Ann Arbor, MI?
The most common FEMA flood zones in Ann Arbor are Zone AE, Zone X. Properties in these high-risk zones (SFHA) may require flood insurance with a federally regulated or government-backed mortgage.
Is flood insurance required in Ann Arbor?
If your Ann Arbor property is in a Special Flood Hazard Area (SFHA) and you have a federally regulated or government-backed mortgage, federal law generally requires your lender to ensure you carry flood insurance. Properties in Zone X are not federally required to carry flood insurance, though coverage is still recommended since about 25% of all NFIP flood claims come from Zone X properties.
How do I check my flood zone in Ann Arbor?
Enter your Ann Arbor address in the search tool above for an instant flood zone determination. Results include your FEMA flood zone, SFHA status, base flood elevation (if available), and FIRM panel information, pulled directly from FEMA's National Flood Hazard Layer.
Does Ann Arbor offer flood insurance discounts?
Yes. Ann Arbor participates in FEMA's Community Rating System (CRS) with a Class 6 rating, qualifying residents in the Special Flood Hazard Area for up to a 20% discount on NFIP flood insurance premiums. Properties outside the SFHA may receive a 10% discount.
Has Ann Arbor experienced major flooding events?
Washtenaw County, where Ann Arbor is located, has been part of 2 federal disaster declarations for flooding, hurricanes, or severe storms. The most recent was Hurricane Katrina Evacuation in 2005. Federal disaster declarations are issued when flooding overwhelms local resources and triggers FEMA assistance programs.
How many flood insurance claims have been filed in Ann Arbor?
Washtenaw County has recorded 132 NFIP flood insurance claims totaling $1.6M in payouts since 1978. The year with the most claims was 2011, with 19 claims and $228K in payouts. These figures cover all NFIP claims in the county, including Ann Arbor.
Sources
This page summarizes information from FEMA and other official resources in plain language. For full technical details, see the links below.
- FEMA National Flood Hazard LayerDirect Source
The NFHL is the source of all flood zone data shown on this page.
- FEMA Map Service Center — Search by AddressDirect Source
Look up any address to view FIRM panels, FIS reports, and LOMCs.
- NFHL Data and Map StatusTopic Page
View NFHL coverage and data freshness by state and community.
- FEMA National Risk Index — Data ResourcesDirect Source
County-level risk scores for inland flooding, coastal flooding, and hurricane used in the Flood Risk Profile.
- OpenFEMA Disaster Declarations Summaries API v2Direct Source
Federal disaster declarations filtered for flood-related incident types (Flood, Hurricane, Severe Storm, Coastal Storm).
- OpenFEMA FIMA NFIP Claims API v2Direct Source
Historical NFIP flood insurance claims since 1978, aggregated by county and state. Includes claim counts, payouts, and flood zone breakdowns.
Sources last verified: February 2026