ParcelSheet

Calhoun County, TX zoning map, flood zone and property lines by address

Free, no account. Or open the Texas map and tap a lot.

Towns in Calhoun County: Port Lavaca, Seadrift, Port OConnor.

Flood zone by address

ParcelSheet reads FEMA's National Flood Hazard Layer at the lot: the zone, whether it is a high risk area where lenders ask for flood insurance, and the base flood elevation where FEMA lists one. FEMA's countywide study for Calhoun County has 35 FIRM panels, the newest effective August 2018; coastal V zones, where waves add to the flood, are mapped along its shore.

The official panel and any Letter of Map Amendment are at FEMA's Map Service Center. An elevation certificate for a Calhoun house comes from a licensed surveyor and is often on file with the county or city building office.

Property lines

The parcel outline, parcel number and mapped size come from the Texas statewide parcel layer (StratMap Land Parcels, Texas Geographic Information Office, from each county appraisal district), so a Calhoun lot shows the same lines the appraisal district draws. Calhoun County covers about 324,439 acres of land and 336,467 acres of water.

Mapped lines are approximate. The Calhoun County appraisal district keeps the parcel record; every county's office is on the state's Comptroller county directory; a licensed surveyor sets the true corners.

Zoning

Texas counties cannot zone land. Under Texas Local Government Code chapter 211 only cities zone: in Calhoun County, Port Lavaca, Seadrift each zone the land inside their limits. Land in Calhoun County outside city limits has no zoning district; deed restrictions, the county's subdivision rules (Local Government Code chapter 232), the septic permit and the floodplain rules still apply.

So check city limits first. ParcelSheet shows the use the appraisal district lists for the lot and the town it sits in; the city planning office has the district for land inside a city. What you can build outside city limits in Texas.

ADU and guest houses

Outside city limits in Calhoun County no county zoning limits a guest house or second home on a lot; deed restrictions and the septic permit, which must cover both homes, decide it. Inside a city, the city's zoning code sets the rule. ParcelSheet shows the mapped lot size and the ground's slope, the first two things the question turns on.

Septic and soil

ParcelSheet reads the USDA soil survey at the lot: the soil's name, its septic absorption rating and whether it is prime farmland. Calhoun County is soil survey area TX057, Calhoun County, Texas, last updated September 2026, on Web Soil Survey.

A new or changed septic system in Calhoun County needs a permit from the Calhoun County authorized agent of the TCEQ on-site sewage facility program, or the TCEQ region office where the county has none, which tests the soil on the lot itself.

Setbacks

Outside city limits in Calhoun County there are no county zoning setbacks; deed restrictions and the county's subdivision rules can still set distances. Inside a city such as Port Lavaca or Seadrift, the city's zoning code sets the front, side and rear setbacks for the lot's district. ParcelSheet does not draw setback lines.

Hazards that apply

Questions

Is my house in a flood zone in Calhoun County?

Type the address in the box above and ParcelSheet reads FEMA's flood zone at the lot's center. FEMA's countywide flood map for Calhoun County has 35 panels, the newest effective August 2018. A lender or insurer uses the official FIRM panel; FEMA's Map Service Center has it.

How do I find property lines in Calhoun County?

Open the Texas map, type the address, and the parcel outline from the Calhoun County appraisal district shows on the map with its parcel number and mapped size. Mapped lines are approximate; only a licensed surveyor sets the true corners.

What is my property zoned in Calhoun County?

Zoning in Calhoun County is set only inside city limits, by each city (such as Port Lavaca, Seadrift); Texas counties cannot zone, so land outside city limits has no zoning district. ParcelSheet shows the use code on the parcel record and names the municipality; the city planning office has the final word.

Can I build an ADU in Calhoun County?

Outside city limits in Calhoun County there is no county zoning, so no zoning rule limits a guest house; deed restrictions, the septic permit and the floodplain rules still apply. Inside a city, the city's zoning code under Texas Local Government Code chapter 211 sets the rule. ParcelSheet shows the lot size as mapped so you can see the room you have.

Do I need a septic permit in Calhoun County?

Yes. A new or changed septic system in Calhoun County needs a permit from the Calhoun County authorized agent of the TCEQ on-site sewage facility program, or the TCEQ region office where the county has none. ParcelSheet shows the USDA soil survey's septic rating at the lot, from survey area TX057 (Calhoun County, Texas).

What can I build on 5 acres in Calhoun County?

Texas counties cannot zone land, so check city limits first. If the 5 acres are inside a city (such as Port Lavaca, Seadrift), that city's zoning sets what can go on them; outside city limits there is no county zoning, and deed restrictions, the county's subdivision and septic rules and the floodplain rules still apply. See the Calhoun County appraisal district.

What are the residential setbacks in Calhoun County (2026)?

Texas counties do not zone, so outside city limits there are no county zoning setbacks; deed restrictions and the county's subdivision rules can still set distances. Inside a city such as Port Lavaca or Seadrift, the city's zoning code sets the front, side and rear setbacks for the lot's district. ParcelSheet does not draw setback lines. See the Calhoun County appraisal district.

Next to Calhoun County: Aransas County, Jackson County, Matagorda County, Refugio County, Victoria County.

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