Two separate systems: groundwater and surface water
Texas water law treats groundwater and surface water completely differently — under different legal doctrines, regulated by different agencies, with different ownership rules. Understanding which type of water you're dealing with is the starting point for everything else.
Groundwater — the rule of capture
Groundwater is water beneath the surface — accessed through water wells. In Texas, groundwater is governed by the Rule of Capture, sometimes called the "law of the biggest pump." Under this doctrine, landowners own the groundwater beneath their property and can pump as much as they want for any beneficial use — even if it drains their neighbor's well.
Texas is one of the few states in the country that still applies a version of the Rule of Capture. The practical result: your neighbor can legally drill a high-capacity well and pump your aquifer dry, and in most cases you have limited legal recourse.
The exception: Groundwater Conservation Districts (GCDs). Most of Texas is covered by GCDs, which have authority to regulate well spacing, pumping rates, and permits. GCDs can and do limit pumping — check whether your county is in a GCD and what the current rules are before drilling.
Groundwater — key facts for landowners
Surface water — prior appropriation
Surface water — rivers, streams, creeks, and natural lakes — is governed by an entirely different system: prior appropriation, or "first in time, first in right." In Texas, surface water belongs to the state. Landowners do not own surface water that flows across their property, even if it's a creek running through the middle of their ranch.
To use surface water, you generally need a water right permit from the Texas Commission on Environmental Quality (TCEQ). Water rights are allocated in order of seniority — older rights get priority in times of shortage. Junior rights can be curtailed entirely in drought years while senior rights continue.
There are important exceptions for small amounts of surface water used for domestic and livestock purposes — most rural landowners can divert limited quantities without a permit for these uses. But selling surface water, diverting large volumes, or using it for irrigation typically requires a permit.
Important: Just because a creek runs through your property doesn't mean you own the water in it. You own the land under and beside the creek (to the center, in most cases), but the water flowing through belongs to the state and is subject to existing water rights held by others downstream and upstream.
Stock tanks and ponds — a special case
Stock tanks and ponds built on private land to capture rainfall and runoff are treated differently from surface water diversion. In most cases, a landowner can build a stock tank without a water right permit, provided:
- The impoundment is under 200 acre-feet of storage
- It's on your own property
- It captures rainwater and runoff (not diverted from a navigable stream)
- It's used for livestock, wildlife, or domestic purposes
This is why stock tanks are so common on Texas ranches — they're one of the few ways a landowner can capture and use water without navigating the full water rights permitting system.
Riparian rights — what about land along a river?
Texas does not follow the riparian doctrine that many eastern states use (where owning land along a waterway gives you water rights). Texas is a prior appropriation state for surface water — owning riverfront property gives you scenic value and physical access to the water, but not the legal right to divert significant quantities without a permit.
You do own the bed of non-navigable streams to the center of the channel. For navigable waterways, the state owns the bed.
Practical implications for Texas landowners
Drilling a water well
Check if your county has a Groundwater Conservation District and what permits are required. Domestic and livestock wells are often exempt from permitting but may still require registration. Get a licensed well driller and pull the appropriate permits.
Building a stock tank
Generally no state permit required for tanks under 200 acre-feet. Check if the site involves a navigable waterway, which would trigger different requirements. Contact TCEQ or NRCS if uncertain.
Irrigating from a creek
Almost certainly requires a TCEQ water right permit. Do not divert without checking your legal right to do so.
Buying land with a well
Test the water. Ask about the aquifer depth and historical yield. Ask whether the area has groundwater regulation through a GCD. A well that produced 20 GPM ten years ago may produce 5 GPM today in an over-pumped aquifer.
Selling water
Groundwater can be sold and transported off your property — this is a growing business in Texas as cities seek new water supplies. If you're in an area with significant aquifer resources, the water beneath your land may have substantial value independent of the surface.
Bottom line
Texas water law is genuinely complicated, and the stakes are high — water is increasingly the most valuable resource on rural land in this state. The key things to know as a landowner:
- You likely own the groundwater beneath your land — but GCDs may regulate how much you can pump
- Surface water in streams and rivers belongs to the state — you need a permit to divert significant quantities
- Stock tanks built to capture rainfall on your own property are generally legal without a permit under 200 acre-feet
- Before drilling a well or building a tank, check with your local GCD and TCEQ
- Water rights are property — if your land has significant water resources, they may be worth more than you think
For any significant water-related decision, consult a Texas water rights attorney. Water law in this state changes regularly and varies significantly by region.