Does Boerne, Texas flood?

Flood risk in Boerne is address-specific, not city-wide. Whether a particular property floods is determined by its FEMA flood zone, the seller's disclosure under Texas Property Code 5.008, and an insurance quote. A property outside the mapped Special Flood Hazard Area can still flood; the map is not a risk assessment.

This page does not assert a flood history for any specific Boerne property, street or subdivision. Anyone who tells you a neighborhood "floods" or "never floods" without naming a map panel, a disclosure or a claims history is guessing. What follows is how to get the real answer on the address you care about, and the order to do it in.

Step one: the FEMA flood map, and what the zone codes mean

Every property in the United States sits somewhere on a FEMA Flood Insurance Rate Map. You find a specific address on the FEMA Flood Map Service Center, which is the official public source for flood hazard information produced in support of the National Flood Insurance Program and searches by address, place or coordinates. The answer comes back as a zone designation.

Texas law builds its flood disclosure on the same two categories, defined in the statutory seller's notice (Texas Property Code §5.008):

100-year floodplain — the Special Flood Hazard Area. Zones A, V, A99, AE, AO, AH, VE or AR. These carry a 1% annual chance of flooding.
500-year floodplain — moderate flood hazard. Shaded Zone X, a 0.2% annual chance.

Two things people misread. "100-year flood" is not a flood that happens once a century; it is the 1%-per-year event, and it can happen in consecutive years. And a zone is assigned to a mapped area, not measured on your slab — two houses on the same street can sit in different zones, and the line can run through a single lot.

If the property is in a Special Flood Hazard Area and there is a federally backed mortgage on it, flood insurance is generally a lender requirement, not a choice. That is a question for the lender and an insurance agent on the specific address.

Step two: the seller's disclosure asks five flood questions, and it is statutory

Since SB 339 of the 86th Legislature, mandatory for contracts executed on or after September 1, 2019, the Texas statutory seller's disclosure notice includes explicit flood items (SB 339; Texas Property Code §5.008).

The notice asks whether the property:

is located wholly or partly in a 100-year floodplain (Special Flood Hazard Area);
is located wholly or partly in a 500-year floodplain (moderate flood hazard area);
has flooded at least once within the past 5 years;
is located in a reservoir flood pool; and
has been repaired for flood damage, or whether the seller has received assistance or flood insurance proceeds for flood damage.

That third and fifth items are the ones that matter most, because they are history rather than mapping. A property can sit outside every mapped zone and still have a disclosed flood and a repair.

Two mechanics on the disclosure itself are worth knowing. The current TREC version of the form is 55-1, effective 05/28/2026 (TREC). And if a contract is signed without the seller having delivered the notice, the buyer may terminate for any reason within 7 days after receiving it — a separate exit from the option period, on its own clock.

The disclosure is what the seller knows. Certain transfers are exempt from the form — foreclosure, court-ordered transfers, transfers by a trustee in bankruptcy, transfers between co-owners, transfers to a spouse or descendant, transfers by a fiduciary administering an estate, and new residences not previously occupied. On an exempt transfer you get no notice at all, which means the mapping and insurance work carries the entire load.

Renters have their own version: TREC publishes a Landlord's Floodplain and Flood Notice, form 54-1, effective 11/26/2025.

Step three: a map designation is not a risk assessment

This is the part that gets people hurt.

FEMA maps are engineering products with a revision date, built on the drainage and development conditions that existed when the study was done. They do not model every creek, every low-water crossing, every undersized culvert, or the parking lot that got paved upstream after the map was drawn. Property outside a Special Flood Hazard Area can and does flood.

Boerne sits in the Hill Country, where Cibolo Creek runs. The Hill Country's combination of thin soil over limestone, steep relief and intense rainfall produces fast-rising water in creek and draw bottoms. The Cow Creek Groundwater Conservation District maintains stream gauges on Cibolo Creek and the Guadalupe River, along with roughly 42 monitor wells and more than 100 rain gauge sites — which is a reminder that surface water here is monitored in real time for a reason.

On a specific property, the questions that actually predict water are physical: where is the lot relative to the creek and to the nearest draw, where does the slab sit relative to the street, where does the neighborhood drain, and is there a low-water crossing between the house and the way out. Walk it, and walk it after a rain if you can.

Step four: do the flood work inside the option period, because it has a deadline

The option period is the window in which a Texas buyer has an unrestricted right to terminate (Texas Real Estate Research Center). It is also the only window in which the flood questions can be answered in time to act on them.

The flood checklist for that window:

Pull the FEMA zone for the exact address, not the subdivision.
Get an actual insurance quote — not an estimate, a quote, on this address, from an insurance agent. Premium and availability are the market's own risk assessment, and they tell you things a map will not.
Ask whether an elevation certificate exists, and whether one would change the rating. This is a surveyor question.
Read the seller's disclosure flood answers, and ask follow-up questions in writing about anything checked or left blank.
Ask the City of Boerne about drainage, floodplain development permits and any local floodplain information for the address. Boerne is in Kendall County, not Bexar County, and it is not in the City of San Antonio — San Antonio's floodplain pages and ordinances do not govern Boerne. City of Boerne: 201 East San Antonio Avenue, Boerne, TX 78006, 830-249-9343. For an address in unincorporated Kendall County, that question goes to the county.
Check the survey for the floodplain line, if the survey shows one.

The mechanical trap is the one that catches every Texas buyer: the option fee must reach the title company within three days of the effective date or there is no termination right at all, no matter what the option period says (TREC). Insurance quotes and elevation certificates take time. Start them on day one, not day seven.

What an honest answer sounds like

"Does Boerne flood?" is the wrong shape of question. "Does 000 Example Street sit in Zone AE, has it flooded in the last five years per the seller's disclosure, and what will an insurer charge to write it?" is answerable, in about three business days, for the price of a phone call.

Who answers which question

An insurance agent — availability, premium, what the carrier's own model says, whether an elevation certificate changes the rate.
A surveyor — elevation certificate, where the floodplain line falls on the lot.
The City of Boerne (or Kendall County for unincorporated property) — drainage, floodplain development permits, local map information.
A lender — whether flood insurance is required for the loan.
A Texas real estate attorney — anything involving a disclosure that turns out to have been wrong.

Questions about a specific property?

Call or text 830-446-3847 · Email heath.shepard@kw.com

This page explains how flood risk is determined on a Texas property and makes no representation about flooding at any specific address. It is not legal, insurance or engineering advice. Get a quote from a licensed insurance agent, an elevation question answered by a surveyor, and floodplain and drainage information from the City of Boerne or Kendall County.