Flood Zones, Low-Water Crossings, and Renter's Insurance Before You Sign a San Antonio Lease

San Antonio doesn't flood the way Houston floods. It floods in narrow, predictable corridors along Salado Creek, Leon Creek, Cibolo Creek, and the Olmos Basin — and it floods hard and fast when it does. A rental two blocks off one of those corridors can be dry for a decade. The one on the wrong side of the street can take on water twice in three years. Before you sign a lease sight-unseen or in a rush, spend twenty minutes verifying the address against three sources: the FEMA flood map, the property's disclosure under Texas Property Code § 92.0135, and the low-water crossing list you'll actually be driving through on your commute.

This is a small amount of work that protects a large amount of money. Standard renter's insurance does not cover flood. If your unit takes on water and you didn't know to ask, your furniture, electronics, and clothes are gone and your policy will pay nothing.

The four water systems that actually matter

Bexar County's flood risk is concentrated along a handful of drainages. If your prospective address is within roughly a quarter-mile of any of these, you need to check the flood map — not skim it, actually pull the address.

• Olmos Basin and Olmos Creek — the basin behind Olmos Dam collects runoff from the north side and feeds the San Antonio River. Neighborhoods on the fringes (parts of Olmos Park, north Alamo Heights, Monte Vista north edge) sit near this drainage.
• Salado Creek — runs north-to-south from Hollywood Park down through the East Side, cutting through Windcrest, parts of 78218 and 78220, and out toward the Southeast. Wurzbach Parkway and much of the East Side greenway system parallels it.
• Leon Creek — the West Side counterpart, running from far north (past 1604) down through 78227 and 78242. Portions of the Leon Creek Greenway are built on floodplain by design.
• Cibolo Creek — the northeast boundary between Bexar, Comal, and Guadalupe counties. Cibolo, Schertz, Selma, and Universal City all have neighborhoods within its flood corridor. New construction on the Cibolo side has pushed into former farmland that historically held water.

Smaller tributaries — Alazán, Apache, Martinez, San Pedro Creek downtown, Rosillo on the far east — carry real risk in short bursts during heavy storms. The 2013 Memorial Day flood and the 1998 flood are the two events longtime residents use as reference points.

Pull the FEMA map yourself

Do not rely on the listing agent, the property manager, or a general "is this a flood zone" search. Go to the FEMA Flood Map Service Center (msc.fema.gov), type in the exact street address, and read the panel. What you're looking for:

• Zone X (unshaded) — minimal risk. Fine.
• Zone X (shaded, 0.2% annual chance) — 500-year floodplain. Lower risk but not zero.
• Zone AE or A — 100-year floodplain. This is the trigger for mandatory disclosure and for lender-required flood insurance if you were buying. As a renter, this is your cue to buy a flood policy or walk.
• Floodway — the channel itself. Don't rent here.

Bexar County also publishes a flood-awareness viewer through Bexar County Public Works, and the San Antonio River Authority (SARA) posts real-time gauge readings during storms. Bookmark SARA's gauge map before your first rainy season.

What Texas law requires the landlord to tell you

Since January 1, 2022, Texas Property Code § 92.0135 has required a landlord to disclose in the lease, in bold or underlined type, whether the landlord has actual knowledge that the dwelling is located in a 100-year floodplain or has flooded at least once in the last five years. The disclosure has to be given before the tenant signs.

A few practical points on that statute:

• "Actual knowledge" is the standard, which means a landlord who genuinely doesn't know is not liable for failing to disclose. That is why you verify independently.
• If the landlord fails to disclose and the unit floods, the tenant can terminate the lease and recover certain damages under the statute. Read the language before you sign anything, and if the disclosure is missing entirely from a Texas Apartment Association lease, ask why.
• A single flood event in the past five years is enough to trigger the disclosure. "It only got a little water in the garage" still counts.

If you're renting from a small individual landlord — common in Converse, on the South Side, and in older neighborhoods like Beacon Hill or Highland Park — the disclosure is more likely to be handled sloppily. Ask directly, in writing (text is fine), whether the property has flooded and whether they know its FEMA zone. Save the reply.

Renter's insurance does not cover flood

A standard HO-4 renter's policy from any Texas carrier covers fire, theft, wind, and most water damage from inside the unit (a burst pipe, an overflowing tub upstairs). It does not cover rising water from outside. If Salado Creek jumps its banks and pushes two feet of water through your ground-floor apartment, an HO-4 pays nothing for your belongings.

Options:

• NFIP contents-only policy — the National Flood Insurance Program sells a renter-level contents policy separately. Coverage is capped and there's a 30-day waiting period before it takes effect, so you cannot buy it the week a hurricane is in the Gulf.
• Private flood carriers — a handful of private insurers write standalone flood in Texas, sometimes faster and cheaper than NFIP for lower-risk properties.
• Choose a unit that isn't in the flood zone — usually the cleanest answer.

Ask your renter's insurance agent point-blank: "Is flood covered under this policy?" The answer will be no. Then decide.

The low-water crossing problem

Even if your rental is bone-dry, your commute might not be. San Antonio has dozens of low-water crossings — road dips where a creek crosses under (or over) the pavement. When it rains hard, they close. The city and TxDOT maintain a real-time closure map, but if your daily drive from a north-side rental to a job at Port San Antonio crosses Salado or Leon Creek at grade, you'll spend a few mornings a year rerouting.

Before you commit to a lease, map your commute to work, daycare, and the grocery store. Search "San Antonio low water crossing map" and see how many your route touches. Six crossings on a 20-minute drive is a lot. Neighborhoods hemmed in by a single access road across a creek — some pockets of far west 78253 and parts of the Hill Country fringe out toward Boerne (78006) — can become genuinely isolated for a few hours after a storm.

What most people get wrong

• Assuming the whole ZIP is safe or unsafe. 78209 has both bone-dry high ground in Terrell Hills and low-lying pockets near the Olmos drainage. Check the address, not the ZIP.
• Trusting the landlord's verbal "no, it doesn't flood." Get it in writing and cross-check FEMA. § 92.0135 protects you only if the landlord actually knew.
• Skipping renter's insurance entirely because "the landlord has insurance." The landlord's policy covers the building, not your stuff. A basic HO-4 in San Antonio runs roughly $12–$25 a month for typical coverage limits.
• Buying a flood policy the day a storm forms. NFIP has a 30-day waiting period. Buy it when you sign the lease or not at all.
• Ignoring ground-floor vs upper-floor risk in the same complex. In a garden-style apartment on Wurzbach or off Loop 410, the second-floor unit is meaningfully safer for the same rent.
• Forgetting the car. Auto comprehensive coverage — not liability — is what pays if your car floods in the parking lot. Confirm you carry it.

A 20-minute pre-signing check

Before you sign, run this list:

1. Pull the exact address on the FEMA Flood Map Service Center. Screenshot the zone.
2. Read § 92.0135 disclosure language in the lease. If it's missing, ask in writing.
3. Search local news for the street name plus "flood" — the 2013 and 1998 events are well documented.
4. Map your commute against the city's low-water crossing list.
5. Get a renter's insurance quote and ask specifically about flood.
6. If the answer is "AE zone," price an NFIP contents policy or move on.

San Antonio's rental market is deep enough that you don't have to accept a flood-prone unit to find something you like. RentInSA's active listings show roughly 4,700 rentals across Bexar and the surrounding counties as of September 2026, with a median asking rent of $1,700 a month — you have options. Browse rentals at /rentals with the address in hand, or explore neighborhood breakdowns and move-timing guides at /resources before you commit.