Ottawa, IL Flood Zone Map
Last updated: August 2026
Ottawa sits at the confluence of the Illinois and Fox rivers in LaSalle County, creating significant riverine flood exposure from two major waterways. The city holds a CRS Class 2 rating, one of the highest in the nation, reflecting decades of proactive floodplain management.
La Salle County has recorded 680 NFIP flood insurance claims since 1978, totaling $12.2M in payouts. Explore the full NFIP claims data by state and county to see how this area compares nationally.
FEMA Region
Region 5
NFIP Policies
328
La Salle County
Avg. Premium
$1,524/yr
La Salle County
NFIP Flood Insurance Claims: La Salle County
Properties in La Salle County have filed 680 NFIP flood insurance claims totaling $12.2M in payouts since 1978. The average claim payout is $18K.
Highest-Claim Years
2008
111 claims - $2.9M
2013
102 claims - $3.6M
1997
64 claims - $1.2M
Claims by Flood Zone
Source: OpenFEMA NFIP Claims API. Data sourced August 2026. See national claims data.
Flood Insurance Coverage: La Salle County
Only roughly 1 in 132 households in La Salle County carries NFIP flood insurance (0.8% of estimated households). With 77 recorded flood events and $88.0M in damage, most flood losses in this county are likely uninsured.
Penetration Rate
0.8%
roughly 1 in 132 households
Historical Claims Ratio
1 in 1
680 claims over 45+ years across 328 current policies
Avg. Claim Payout
$17,907
Per claim, county-wide since 1978
Historically, La Salle County has averaged 2.1 claims for every active policy (since 1978). This compares cumulative claims against today's policy count and does not predict future claim likelihood.
Coverage data: NFIP policies as of August 2026, claims since 1978 (August 2026), population from FEMA NRI. All figures are county-wide and include Ottawa.
Not sure whether you're required to carry it? See do I need flood insurance?, or compare NFIP vs. private flood insurance.
Repetitive Loss Properties: La Salle County
La Salle County has 68 properties with multiple flood insurance losses, including 12 severe repetitive loss properties. 13 properties have received FEMA mitigation funding. Severe repetitive loss is a subset of multiple loss, not a separate count. Data sourced August 2026.
Multiple Loss
68
2+ claims within 10 years
Severe Repetitive Loss
12
4+ claims or 2 exceeding value
Mitigated
13
Received FEMA mitigation
By Flood Zone
Zone data available for 64 of 68 properties.
Source: OpenFEMA NFIP Multiple Loss Properties. Data sourced August 2026.
Flood Insurance Discount: Ottawa
Ottawa 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 2
SFHA Premium Discount
40% off
CRS classes range from 1 (best) to 10 (no discount). Ottawa's Class 2 rating means NFIP policyholders in the SFHA can receive up to a 40% discount on their flood insurance premiums. Properties outside the SFHA may receive a 10% discount.
Source: FEMA Community Rating System, April 2026. Discounts apply to NFIP policies only.
Federal Flood Disaster History: La Salle County
La Salle County has been included in 7 federal flood-related disaster declarations.
These declarations affected communities across La Salle County, including Ottawa.
Source: OpenFEMA Disaster Declarations Summaries API. Data sourced August 2026.
Recorded Flood Events: La Salle County
NOAA has recorded 77 flood events in La Salle County since 1996, causing $88.0M in damage and 1 death.
Costliest Events
Events by Type
Source: NOAA Storm Events Database, 1996-2026. Data sourced August 2026.
Flood Mitigation: La Salle County
FEMA has funded mitigation for 119 properties in La Salle County, investing $2.5M in flood risk reduction. Common mitigation actions include acquisition (buying and demolishing flood-prone structures), elevation (raising buildings above flood level), and safe rooms (wind/storm shelters for tornado and hurricane protection).
By Action Type
Source: OpenFEMA Hazard Mitigation Assistance. Data sourced August 2026. FEMA records a total payment per grant rather than per property, so the dollar figure is an estimate that splits each grant across the properties it covers; the property count is exact.
Levee Protection: Ottawa
The USACE National Levee Database lists 2 levee systems protecting parts of Ottawa. A system's FEMA accreditation status determines how its protected area is mapped: accredited levees are typically mapped as Zone X, while non-accredited or provisionally accredited systems generally leave their protected area in the Special Flood Hazard Area (often Zone AR or A99) until certification is complete.
Ottawa WWTP
Non-AccreditedProtects against: Illinois River - Sponsor: City of Ottawa, IL - 0.01 sq mi protected
Ottawa Township High School Levee, Il
Non-AccreditedProtects against: Fox River - Sponsor: Ottawa Township High School - 0.1 sq mi protected
Source: USACE National Levee Database. Data sourced August 2026. Learn how levees affect flood zone mapping.
FEMA Flood Risk Profile: LaSalle 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: $33.1M
Hurricane Risk
Very LowEst. annual loss: $15K
Source: FEMA National Risk Index, county-level assessment. Individual property risk may vary.
What Your Flood Zone Means in Ottawa
Ottawa 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 Ottawa are Zone AE, Zone X. FEMA's National Risk Index estimates the county's annual expected loss from inland flooding at over $33.1M.
Riverine flood risk in Ottawa 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 Ottawa address.
Ottawa, IL Flood Zone FAQ
What flood zones are in Ottawa, IL?
The most common FEMA flood zones in Ottawa 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 Ottawa?
If your Ottawa 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 a quarter of all NFIP flood claims come from properties outside high-risk zones.
How do I check my flood zone in Ottawa?
Enter your Ottawa 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 Ottawa offer flood insurance discounts?
Yes. Ottawa participates in FEMA's Community Rating System (CRS) with a Class 2 rating, qualifying residents in the Special Flood Hazard Area for up to a 40% discount on NFIP flood insurance premiums. Properties outside the SFHA may receive a 10% discount.
Has Ottawa experienced major flooding events?
La Salle County, where Ottawa is located, has been part of 7 federal disaster declarations for flooding, hurricanes, or severe storms. The most recent was Severe Storms, Straight-Line Winds, and Flooding in 2013. Federal disaster declarations are issued when flooding overwhelms local resources and triggers FEMA assistance programs.
How many flood insurance claims have been filed in Ottawa?
La Salle County has recorded 680 NFIP flood insurance claims totaling $12.2M in payouts since 1978. The year with the most claims was 2008, with 111 claims and $2.9M in payouts. These figures cover all NFIP claims in the county, including Ottawa.
How many flood insurance policies are there in Ottawa?
La Salle County had 328 NFIP flood insurance policies written or renewed over the trailing 13 months, with an average annual premium of $1,524. The most policies are in Zone AE (157 policies). These are county-level counts of policies written or renewed in the trailing 13 months, not a point-in-time count of policies in force - a policy renewed inside that window is counted twice.
How many Ottawa properties have flooded repeatedly?
La Salle County has 68 properties with multiple flood losses on record, including 12 severe repetitive loss properties. These are properties that have experienced four or more NFIP claims of $5,000+ or two claims exceeding the building value.
Is Ottawa protected by a levee?
Yes. The USACE National Levee Database lists 2 levee systems protecting parts of Ottawa. None currently carry full FEMA accreditation, which typically keeps the protected area within the Special Flood Hazard Area (often Zone AR or A99) until the levee is certified. Levee protection is system-specific, not city-wide - check the address search above for the zone at a specific property.
Can my Ottawa property be removed from a high-risk flood zone?
Yes, if your property's natural ground elevation is above the Base Flood Elevation and FEMA inadvertently mapped it in a high-risk zone, you can apply for a Letter of Map Amendment (LOMA). A successful LOMA removes the property from the Special Flood Hazard Area, generally eliminating the federal mandatory flood insurance requirement. You will need an elevation certificate from a licensed surveyor. If a property was raised above the BFE with fill material, the process is a LOMR-F rather than a LOMA.
What is Base Flood Elevation in Ottawa?
Base Flood Elevation (BFE) is the predicted height of floodwaters during a 1% annual chance (100-year) flood, shown on FEMA maps as an elevation number in feet above sea level. In Ottawa's Zone AE areas, BFE lines appear on the FIRM as wavy contours labeled with elevation values. Properties with a lowest floor at or above the BFE typically qualify for significantly lower NFIP flood insurance premiums.
Other Illinois Cities
Understanding Flood Zones
See the Flood Map for Any Ottawa, IL Address
Enter a Ottawa, IL address to view its FEMA flood map, zone designation, SFHA status, and insurance requirements.
Disclaimer: Flood risk data on this page is sourced from FEMA datasets including the National Risk Index, NFIP claims and policy records, disaster declarations, and the Community Rating System. These datasets were last extracted on August 2026 and may not reflect the most recent changes. Always verify current flood zone status through FEMA or a licensed determination provider before making property, insurance, or lending decisions.