Entitlement guide
The Edwards Aquifer.
Much of the Hill Country edge drains into the Edwards Aquifer, a drinking water source for millions. Building over it takes extra plans, studies and time.
The short answer
The Texas Commission on Environmental Quality, TCEQ, regulates development over parts of the Edwards Aquifer under its Edwards rules. The key zones are the recharge zone, where water enters the aquifer through the surface, and the contributing zone upstream of it.
On the recharge zone, regulated development generally needs an approved Edwards Aquifer protection plan and a geologic assessment before construction starts. In the contributing zone, larger projects generally need a contributing zone plan. Both usually require permanent water quality controls.
Cities can add their own, often stricter, watershed rules on top. Those can include impervious cover limits and buffers around caves, sinkholes and springs.
- Recharge, contributing and transition zone overlap, with acres
- State plan requirements for the planned disturbance
- City watershed rules and impervious cover limits
- Mapped caves, springs and other critical features nearby
- Habitat plans and species concerns for karst areas
Why it can stop a deal
Where projects get caught.
Approval comes before construction
On the recharge zone, the state plan generally has to be approved before ground is broken. It belongs early in the schedule.
Sensitive features move the plan
Caves, sinkholes and fractures found in the geologic assessment can require setbacks. Features found during construction can stop work until a plan is approved.
Local rules stack on state rules
A city watershed ordinance can limit impervious cover and require treatment beyond the state rules. The stricter rule governs.
How it works
How it usually works in Central Texas.
Rules differ by city, county and utility, and they change. Treat this as orientation and confirm with the approving authority.
The zones
TCEQ maps the recharge zone, the contributing zone and a transition zone. Map lines are drawn at a regional scale, so parcels near a boundary need a closer look. We report the share of the parcel in each zone and flag slivers for review.
Recharge zone plans
A water pollution abatement plan, often called a WPAP, describes how the project will control pollution during and after construction. It is supported by a geologic assessment that identifies sensitive features. TCEQ reviews the plan before construction begins.
Contributing zone plans
In the contributing zone, a contributing zone plan is generally required when a project disturbs a larger area of land, including smaller sites that are part of a larger common plan. The plan covers construction and permanent controls.
Permanent controls
Plans generally require permanent best management practices, such as water quality ponds or filters, sized to treat runoff from new impervious cover. These take land and need maintenance commitments.
Local overlays and species
Some cities apply their own watershed protection rules, with impervious cover limits by zone and buffers around critical features. Karst areas can also host protected species, and regional habitat conservation plans may offer a path to compliance. These are checked alongside the state rules.
Who decides
The people and offices involved.
| Who | What they decide |
|---|---|
| TCEQ regional office | Edwards Aquifer protection and contributing zone plans |
| City environmental review | Local watershed and critical feature rules |
| Your geologist | The geologic assessment and sensitive features |
| Your civil engineer | Permanent water quality controls and the plan |
- How much of the parcel is in the recharge or contributing zone?
- Which state plan applies to the planned disturbance?
- Does a city watershed ordinance add limits?
- Are there known caves, sinkholes or springs nearby?
- Where will permanent water quality controls go?
Keep reading
Waitlist open · Starting in Central Texas
Get on the list before your next site.
VALITER opens to a small group first, starting in Central Texas. Teams with a live site get in first.