Austin flood zone map: how to check an address before buying a home

Where is the Austin flood zone map (FloodPro), and which one should you use?

The Austin flood zone map most buyers need is FloodPro, the City of Austin's floodplain mapping tool at maps.austintexas.gov/floodpro, and the second map to open is FEMA's Flood Map Service Center at msc.fema.gov. FloodPro lets you find floodplain information for an address, find elevation certificates, research FEMA map change information, download floodplain models and print a floodplain map, according to the City's service page. FEMA's Map Service Center describes itself as “the official public source for flood hazard information produced in support of the National Flood Insurance Program,” and it is the map a lender and an insurer will use.

The two Austin flood maps do not always agree, and that is by design. FEMA's Flood Insurance Rate Map sets the Special Flood Hazard Area that triggers a mortgage lender's insurance requirement. The City of Austin draws its own regulatory floodplain for a fully developed watershed, and since the Atlas 14 changes described below it is generally wider than FEMA's current 100-year zone; areas shown in light blue on FloodPro are “in the fully developed floodplain and subject to floodplain regulations,” per the City's floodplain management page. A house can sit outside FEMA's zone and inside the City's, which matters the day you apply for a permit.

Both tools carry the same caution. The City says FloodPro is for informational purposes and “does not represent an on-the-ground survey,” and FEMA notes that “effective information that you download or print from this site may change or become superseded by new maps over time.” Search the exact street address rather than the neighborhood, save a dated copy of what each map shows, and treat it as the first document in the file rather than the last. The property research desk lists the other public records to pull for the same address.

Sources: City of Austin ↗ · FEMA ↗ · City of Austin Watershed Protection ↗

What do Zone AE, Zone X and the 100-year floodplain mean on an Austin map?

On an Austin flood zone map, the 100-year floodplain is “the land that is predicted to flood during a 100-year storm, which has a 1% chance of occurring in any given year,” in the City of Austin's words. FEMA labels that same area the Special Flood Hazard Area and marks it Zone A, AE, AO, AH, A99, AR, V or VE; the 500-year floodplain, with a two-tenths of one percent annual chance of flooding, is Zone X (shaded). Those definitions come from the Texas Seller's Disclosure Notice itself, which reproduces them so a seller can answer the flood questions on the form.

The percentages describe a chance each year, not a schedule. A 1% annual chance compounds: over a 30-year mortgage the odds of at least one such flood at a 100-year-floodplain address work out to about 26%, by our computation from the annual figure. The table puts the labels side by side with what each one does to a purchase.

Two labels deserve extra care. A floodway is the channel and adjacent land that “must be reserved for the discharge of a base flood,” the most restricted part of the floodplain. And the light-blue City of Austin fully developed floodplain on FloodPro is a local regulatory line that a FEMA map does not show at all. A parcel can carry a FEMA Zone X label and still fall under City floodplain rules, so read both maps before assuming anything about a remodel.

Sources: City of Austin Watershed Protection ↗ · Texas Real Estate Commission ↗ · FEMA FloodSmart for agents ↗ · City of Austin ↗

How did Atlas 14 change Austin's floodplain maps?

Austin's floodplain maps grew after Atlas 14, a National Weather Service rainfall study for Texas completed in 2018. The City's floodplain management page says the study “shows that Central Texas is experiencing heavier rainfall and that severe flooding is more likely than previously thought,” and the City updated its floodplain regulations in November 2019 to match. Until each creek's study is redone, the interim rule lets a floodplain determination use the Atlas 14 rainfall data, the current FEMA 500-year floodplain, or the current 500-year rainfall, per the City's August 2019 summary of the code changes; the Colorado River kept its existing floodplain.

The City counted what that meant building by building. A council-district summary dated September 30, 2019 lists 3,969 buildings in the then-current 100-year floodplain and 3,237 more in the 500-year floodplain, 7,206 in all out of 244,833 buildings in the city, or 2.9%. Of those, 3,086 single-family homes, duplexes or mobile homes stood in the 100-year floodplain and 2,723 in the 500-year floodplain. Because the interim rule treats the old 500-year line as the new 100-year line, the 7,206 total is the better guide to how many buildings came under the wider regulations.

FEMA's own maps have not all caught up, which is why the City's map and FEMA's can differ at the same address. A property that appears only in the 500-year zone on the FEMA map may be inside the City's regulatory 100-year floodplain, and the seller's disclosure form asks about both. Council districts are not neighborhoods, so the table says nothing about any particular street; it shows how unevenly the risk is spread across the city.

Sources: City of Austin Watershed Protection ↗ · City of Austin ↗

What can you build or remodel on an Austin lot in the floodplain?

A house in the City of Austin's 100-year floodplain can be remodeled and even replaced, but the rules shape what is possible. New foundation floor slabs “must be a minimum of two (2) feet above the 100-year floodplain elevation,” per the City's floodplain regulations page, and the Atlas 14 amendments raised that freeboard from one foot to two. Normal access to a building must be at least one foot above the 100-year floodplain, a site plan is required for all development proposed within the 100-year floodplain, and Chapter 25-7-92 prohibits buildings or parking areas from encroaching on the 25-year floodplain.

The 2019 amendments added a redevelopment exception that matters for older houses: a new residential building may encroach within the 100-year floodplain if it replaces an existing, legally constructed residential building without increasing the number of dwelling units, regardless of when the lot was platted. Variances to build otherwise “are considered by the City Council” and must be requested in writing. The Development Services fee schedule in effect since October 1, 2025 prices the reviews.

Check the floodplain question before falling for a plan. An addition, a garage conversion or a pool that would be routine on a dry lot can require a detailed floodplain review, an engineer's elevation work or a Council variance in the floodplain, and the Austin permit search guide shows how to see whether past work on the house went through that review. A raised older house may be the best-positioned building on its street precisely because it was built above the water; the older-home guide covers what else to check on one.

Sources: City of Austin Watershed Protection ↗ · City of Austin ↗ · Austin Development Services ↗

What does a Texas seller have to disclose about flooding?

A Texas seller of a previously occupied single-family home gives the buyer a Seller's Disclosure Notice, and the current TREC form asks ten flood questions. The seller states whether the property is wholly or partly in a 100-year floodplain, a 500-year floodplain, a floodway, a flood pool or a reservoir; whether there has been previous flooding from a failure, breach or controlled release of a reservoir; whether water has previously penetrated a structure on the property in a natural flood event; whether there is present flood insurance coverage; whether the seller has ever filed a flood damage claim with any insurer, including the National Flood Insurance Program; and whether the seller has ever received FEMA or U.S. Small Business Administration assistance for flood damage. TREC prepares the form under Section 5.008(b) of the Texas Property Code.

Read the answers against the map, not instead of it. A seller answers from awareness, so “no” to previous water penetration does not establish that the house never flooded before this owner bought it, and “unknown” is a question for the neighbors, the City's Floodplain Office at 512-974-2843 and an elevation certificate on FloodPro. The form's own footnote says homes in high-risk flood zones with mortgages from federally regulated or insured lenders are required to have flood insurance, and that FEMA encourages owners in moderate and low-risk zones to buy it too.

Sellers should do the same homework before listing. If FloodPro shows the parcel touching a floodplain, print the map, pull the elevation certificate if one exists, and disclose it plainly; a surprise late in the option period costs more than an accurate disclosure at the start. The selling page covers how the disclosure fits into a listing timeline.

Sources: Texas Real Estate Commission ↗ · City of Austin ↗

How much is flood insurance in Austin, and when is it required?

Flood insurance in Austin costs $670 a year for the average policy, and “policies in floodplain areas typically cost more than $1,000,” according to the City of Austin's October 20, 2025 announcement of its Flood Insurance Assistance Program. Every policy in the city is eligible for a Community Rating System discount of up to 25%: a November 6, 2024 Watershed Protection memorandum to the City Council reports that Austin “recently secured a class 5 CRS rating,” that the top rating is 1, and that of the 73 Texas cities in the program only two rate better than 5 and only ten, including Austin, rate 5.

The National Flood Insurance Program sets the rest of the terms. Homes in Special Flood Hazard Areas with mortgages from federally regulated, supervised and insured lenders are required to carry flood insurance, and lenders typically require only the loan amount, which can be less than the value of the home. Building coverage runs up to $250,000 and contents coverage up to $100,000; landscaping, decks, pools and fences are not covered, nor is temporary housing. There is typically a 30-day waiting period before a new policy takes effect, waived when the policy is bought in connection with making, increasing, extending or renewing a mortgage loan.

Two facts argue for a quote on every house, not only mapped ones. FEMA's FloodSmart site says almost one-third of NFIP claims come from outside high-risk flood areas, and that “most homeowners insurance does not cover flood damage.” Get an address-specific quote during the option period, because the premium depends on the building's elevation and construction, and fold it into the same monthly figure as taxes; the Austin property tax budget guide shows how to build that number from the parcel. Owners inside the 100-year floodplain with household income at or below 140% of the median family income could apply for up to $2,000 toward a policy under the City's pilot program, whose application deadline was extended to January 31, 2026.

Sources: City of Austin ↗ · City of Austin Watershed Protection ↗ · FEMA FloodSmart for agents ↗ · FEMA FloodSmart ↗

Which Austin neighborhoods have mapped floodplain?

Flood zone is a parcel-by-parcel fact, so no Austin neighborhood is “in” or “out” of the floodplain as a whole. Central Austin neighborhoods named for creeks are where the maps most often matter: our Bouldin Creek guide notes that part of that planning area lies in the mapped 100-year floodplain, FEMA Zone AE, computed from the City's floodplain layer, and that it carries the most mapped floodplain of the six neighborhoods we cover. The Zilker guide records the same for part of Zilker, whose streets drain to Lady Bird Lake, West Bouldin Creek and Barton Creek.

The City's 2019 council-district counts tell the same story at a larger scale. Districts 3, 4 and 5 each had more than 500 buildings in the then-current 100-year floodplain and District 7 had 495, while District 10 had 217 and District 6 had 205. A watershed boundary is not a flood zone either; it says where rain drains, not whether a parcel is mapped as at risk. Use the neighborhood guides to understand the terrain, then confirm the specific lot on both maps.

Sources: City of Austin ↗

What should an Austin buyer do with the FloodPro result and elevation certificate?

Start the Austin flood map check the day the offer is accepted, because the option period is the only window in which the answer can still change your terms. Save a dated FloodPro map and a FEMA map for the exact address, note whether the building footprint, the driveway or only a corner of the lot touches a zone, and look for an elevation certificate on FloodPro; if none exists and the house is in a zone, a surveyor can produce one, and the insurance quote will depend on it.

Then separate the map from the site. Ask the inspector about grading, gutters, drainage and evidence of past water entry, because a Zone X label says nothing about a low slab on a street that ponds. Get the flood insurance quote in writing before the option period ends, and if the house is a remodel candidate, ask the City's Floodplain Office whether the plan would need a floodplain review or a variance before you count on it.

If you want a second set of eyes on what the maps show for a specific address, bring it to David with the listing. He can pull the floodplain layers, the elevation certificate and the permit history for the parcel and put the open questions to the right office.

Sources: City of Austin ↗ · City of Austin Watershed Protection ↗