The Edwards Aquifer contributing zone in Travis and Williamson County, and the plan it adds

TCEQ's official maps decide it, and nothing on this page can stand in for them. TCEQ says the official boundaries of the regulated zones were drawn on USGS topographic base maps and are kept in its offices, that its online map viewer shows whether a project is over a regulated zone, and that the viewer is informational and not suitable for legal, engineering or surveying purposes. No TCEQ page read describes a formal written zone determination for a parcel. What the pages offer is the viewer and the Austin Regional Office at (512) 339-2929, the office that handles Travis, Williamson and Hays counties.

What the rule says about these two counties is a watershed description, not a parcel list. The construction general permit's definitions section defines the contributing zone as the area or watershed where runoff from precipitation flows downgradient to the recharge zone, upstream and generally north and northwest of it. For Travis County the definition covers all areas except the Colorado River watershed above a point 1.3 miles upstream from Tom Miller Dam. For Williamson County it covers all areas except the Lampasas River watershed above the Stillhouse Hollow dam. The recharge zone is the area designated on official maps kept in TCEQ offices and the regional office.

So the honest order is: read the definition, look at the viewer, then confirm with the regional office before anyone prices the site work. The zone question comes before the slab design, because the answer changes what has to be approved first.

SourcesThe agency pages were read and describe no written parcel determination.Texas Commission on Environmental Quality, Edwards Aquifer map viewer, read 2026-09-20; Texas Commission on Environmental Quality, TPDES general permit TXR150000, 2023 construction general permit, Part I.B definitions, read 2026-09-20; Texas Commission on Environmental Quality, Edwards Aquifer Protection Program, read 2026-09-20.

A Contributing Zone Plan. TCEQ requires one for any regulated activity proposed in the contributing zone under 30 TAC 213.21, and it has to be approved before construction begins. TCEQ's decision page sorts a project with two questions: is the work a regulated activity under 30 TAC 213.22(6), and will it disturb at least five acres or is it part of a larger plan of development or sale under 213.21(b). A project that does not meet those tests needs no plan, in the page's words. The plan has to include construction stormwater controls, and the pollution prevention plan written for the TPDES construction general permit can satisfy that part.

The recharge zone is a different plan and a stricter posture. A site on the recharge zone files a Water Pollution Abatement Plan for any regulated activity, which TCEQ's page says includes construction of buildings and roads and clearing or excavation, approved before construction. A site that is partly on the contributing zone and partly on the recharge zone is treated as entirely recharge zone. TCEQ's program page adds that only portions of the aquifer are regulated, and that before building on the recharge, transition or contributing zones the plan has to be reviewed and approved by the program first.

SourcesTexas Commission on Environmental Quality, Edwards Aquifer Protection Program, what plans you might need, and the Contributing Zone Plan page, read 2026-09-20; Texas Commission on Environmental Quality, Edwards Aquifer Protection Program, read 2026-09-20.

Two clocks, back to back, both from 30 TAC 213.4(e): the agency takes as long as 30 days to accept the application as administratively complete, and 90 days for the technical review after that. Affected jurisdictions and the public get 30 days to comment. Each notice of deficiency gives you 14 days to respond, and every one of them is time the plan is not moving. Construction may not begin until approval is issued.

The office is one place. Since October 16, 2023 all Edwards Aquifer applications and fees are managed by staff in the Austin Regional Office, which handles Williamson, Travis and Hays counties, at (512) 339-2929.

The stormwater permit says the same thing from the other side. Part II.C.5 of the construction general permit states that construction at a site regulated under 30 TAC Chapter 213 may not begin until the Edwards Aquifer protection plan is approved. Whatever the stormwater tier your acreage lands in, the aquifer approval is the one that has to be in hand first.

SourcesTexas Commission on Environmental Quality, Edwards Aquifer Protection Program, read 2026-09-20; Texas Commission on Environmental Quality, TPDES general permit TXR150000, 2023 construction general permit, Part II.C.5, read 2026-09-20.

Two things: the controls during construction, and the impervious cover that stays. During construction the plan has to include stormwater controls, and the pollution prevention plan written for the TPDES construction general permit can satisfy that part. After construction the number that matters is impervious cover. The Contributing Zone Plan application, form TCEQ-10257, states that the executive director may waive other permanent controls for a multi-family, school or small business site with 20 percent or less impervious cover, with the exemption recorded in county deed records. The waiver is written for a site at or under that line. The same form has a Texas licensed professional engineer certify the permanent controls within 30 days of site completion.

The share is impervious cover against the size of the site, so the parcel counts as much as what goes on it. That is a design decision to settle before the pad is graded, and it belongs on the same sheet as the drainage.

The stormwater permit adds two Edwards-specific lines of its own. New discharges in the recharge zone or the contributing zone must meet Chapter 213 in addition to the permit, and within ten stream miles upstream of the recharge zone a copy of the Notice of Intent also goes to the regional office. The acreage tiers themselves do not change: a site that disturbs five acres or more is a large construction activity, one to under five is small, and under one acre that is not part of a larger common plan is not regulated by the permit. The grading, the drainage and the tiers by acreage are on the pad grading and site prep guide.

SourcesTexas Commission on Environmental Quality, Edwards Aquifer Protection Program, what plans you might need, and the Contributing Zone Plan page, read 2026-09-20; Texas Commission on Environmental Quality, Contributing Zone Plan application, form TCEQ-10257, read 2026-09-20; Texas Commission on Environmental Quality, TPDES general permit TXR150000, 2023 construction general permit, Part II.C.5, read 2026-09-20; Texas Commission on Environmental Quality, stormwater general permit for construction activities (TXR150000), read 2026-09-20.

TCEQ publishes a set of outs for a single-family residence on the recharge or contributing zone, and none of them is written for a business building. Its page names three ways out for a residence: the lot already falls under an approved master community plan; the tract runs over five acres and carries no second residence; or impervious cover inside the legal boundaries stays at 20 percent or less. Miss all three and the residence files an individual plan or asks for an exception. Those exemptions are for a residence. A commercial metal building reads from the non-residential column of the fee form and from the regulated-activity test, not from the residence page.

A metal shop or workshop on a house lot is the case to ask about by name, because the residence page is written around the residence and not around a shop. Put the question to the Austin Regional Office with the parcel in hand rather than assuming the house's exemption covers the shop.

SourcesTexas Commission on Environmental Quality, Edwards Aquifer, private residences, read 2026-09-20; Texas Commission on Environmental Quality, application fee form TCEQ-0574, Edwards Aquifer Protection Program, read 2026-09-20; Texas Commission on Environmental Quality, Edwards Aquifer Protection Program, what plans you might need, and the Contributing Zone Plan page, read 2026-09-20.

TCEQ's fee form, TCEQ-0574, carries the Chapter 213 fee schedule, and it applies to both plan types by project area. A non-residential site, which the form lists as commercial, industrial, institutional, multi-family and schools, pays by acreage, and one single family dwelling under five acres pays $650. Every tier prints beside the other agency fees on the cost guide.

That figure is the fee TCEQ collects with the application. It is not the cost of preparing the plan or of building the controls it calls for, and no agency page prices either of those. Only the professionals you hire for the plan and the independent local metal building contractor who walks your site can put numbers on them. The non-residential tiers on the form:

• $3,000 under one acre

• $4,000 from one to under five acres

• $5,000 from five to under 10 acres

• $6,500 from 10 to under 40 acres

• $8,000 from 40 to under 100 acres

• $10,000 at 100 acres or more

SourceTexas Commission on Environmental Quality, application fee form TCEQ-0574, Edwards Aquifer Protection Program, read 2026-09-20.

The plan is TCEQ's, and the building permit, where there is one, is the county's or the city's. In unincorporated Williamson County there is no county building permit to stack it with: the county's own pages say it issues no building permits, has no authority to issue a Certificate of Occupancy and reviews almost no site plans, and the same FAQ says that cities within their ETJ, emergency services districts, TCEQ and the health district may require permits. That last clause is where the aquifer plan lives in Williamson County. The county's septic program carries one aquifer line of its own: a system design over the Edwards Aquifer recharge zone or in the 100-year floodplain comes from a Texas registered sanitarian or professional engineer.

Unincorporated Travis County does run a permit desk. A commercial project that is not a dwelling applies for a Development (Non-Residential) permit with a sealed construction cost estimate and a site plan sealed by a Texas-licensed engineer, and a pre-construction meeting sets which inspections apply. The county pages read describe no structural plan review by the development office. The TCEQ approval and the county permit are two separate desks with two separate clocks.

Inside a city, the city runs its own permit, and the switch at the top of this page shows both of Travis County's branches. Where the whole path runs, from the jurisdiction question through the slab, the permit, the accessibility line and this plan, is the Austin-area metal building guide.

SourcesTexas Commission on Environmental Quality, Edwards Aquifer Protection Program, read 2026-09-20; The source was read and does not list this.Williamson County, frequently asked questions, infrastructure and developers, read 2026-09-20; Williamson County, on-site sewage facilities, and the OSSF program fee sheet, read 2026-09-20; Travis County TNR Development Services, Commercial Site Plan, read 2026-09-20.

One more name comes up on a Travis County search, and it is not a building approval. The Barton Springs Edwards Aquifer Conservation District says its territory covers 430 square miles in parts of Travis, Hays and Caldwell counties, with its original territory running from the Colorado River in Austin to northern Kyle. Every well inside the district has to be registered, a permit is required to drill a new Edwards or Trinity well, and an exempt well for domestic or livestock use on ten acres or more needs a New Exempt Well application with a $450 fee. The district's pages describe nothing that reaches a building owner who is not drilling or owning a well. If the shop or the warehouse runs on a well, the district is a stop. If it runs on a utility line, it is not.

The other four counties on this site, Bastrop, Caldwell, Lee and Burnet, carry no aquifer plan step on their pages, because no record read for them names them in the program. TCEQ's program page names eight counties and puts Travis and Williamson with Hays under the Austin Regional Office. A lot near a county line is a case for the regional office, not for a guess.

SourcesBarton Springs Edwards Aquifer Conservation District, well permits and forms, read 2026-09-20; Texas Commission on Environmental Quality, Edwards Aquifer Protection Program, read 2026-09-20.