No issue shapes the long-term Texas environment more than water — how much there is, where it is, and who needs it. The supply is fixed and unevenly spread: the wet eastern third of the state holds most of the rain and rivers, while the booming, drier center and west hold much of the population and the irrigated farmland. As the state grows toward and past 30 million people, the question is not whether Texas has enough water in total, but whether each place does.
Rather than dictate one statewide answer, Texas plans water from the bottom up. The state is divided into sixteen regional water planning groups, labeled A through P, each made up of local water utilities, farmers, industry, environmental interests and the public. Every five years each region produces its own plan, and those plans are stitched together by the Texas Water Development Board into the State Water Plan.
The sixteen planning regions
Each region is built around shared water sources and shared problems — a major aquifer, a river basin, a metro area. The lettered names are how Texas water policy is actually discussed.
| Region | Name | Anchor area / source |
|---|---|---|
| A | Panhandle | Amarillo · Ogallala Aquifer |
| B | Region B | Wichita Falls · Red River basin |
| C | Region C | Dallas–Fort Worth · Trinity basin |
| D | North East Texas | Sulphur & Cypress basins |
| E | Far West Texas | El Paso · Rio Grande |
| F | Region F | Midland–Odessa · Edwards-Trinity |
| G | Brazos G | Waco · Brazos River basin |
| H | Region H | Houston · San Jacinto & coast |
| I | East Texas | Tyler–Lufkin · Neches basin |
| J | Plateau | Hill Country · Edwards Plateau |
| K | Lower Colorado | Austin · Highland Lakes |
| L | South Central Texas | San Antonio · Edwards Aquifer |
| M | Rio Grande | Lower Valley · Rio Grande |
| N | Coastal Bend | Corpus Christi · Nueces basin |
| O | Llano Estacado | Lubbock · Ogallala Aquifer |
| P | Lavaca | Lavaca River basin |
Where the water comes from
Two kinds of supply carry the state, in very different proportions from region to region:
- Groundwater from major aquifers — the vast but slowly recharging Ogallala under the High Plains, the karst Edwards that supplies San Antonio, the Gulf Coast, Carrizo-Wilcox, Trinity and Edwards-Trinity aquifers. Groundwater supplies a majority of the water used statewide, and nearly all of it in irrigated regions.
- Surface water from rivers and the reservoirs built to hold it. The cities of Central and East Texas lean heavily on reservoirs in the Trinity, Brazos and Colorado basins.
On the High Plains, more than nine-tenths of the water used is pumped from the Ogallala Aquifer — and across much of the region it is withdrawn far faster than rainfall can replace it. Region by region, the plans must account not just for drought, but for sources that are themselves shrinking.
Rising demand, shifting uses
Statewide, irrigation has long been the largest single use of water, concentrated on the High Plains and in the Rio Grande Valley. But the fastest-growing demand is municipal — the cities. As Texas adds millions of residents, water once destined for farm fields is increasingly bid away to taps, and the planning regions around the big metros (C, H, K, L) face the steepest climbs.
Closing the gap
Each regional plan proposes specific "water management strategies" to close its projected shortfall in a drought. Across the state they fall into a familiar set:
- Conservation — the cheapest new supply, from leak repair to efficient fixtures and irrigation.
- New reservoirs and pipelines — expensive, slow, and increasingly contested.
- Reuse of treated wastewater for irrigation, industry and even drinking supply.
- Desalination of brackish groundwater and, on the coast, seawater.
- Aquifer storage and recovery — banking surplus water underground for dry years.
The mix differs by region because the problems do. What works for Houston has little to do with what works for Lubbock — which is exactly why Texas plans its water sixteen times over. The same logic runs through the state's ecological regions: in Texas, almost everything environmental is regional first.
Sources & further reading
- Texas Water Development Board (TWDB), State Water Plan and regional water plans (Regions A–P).
- TWDB, Texas Aquifers Study and historical water-use estimates.
- Texas Living Waters Project, analyses of state water planning.
- U.S. Geological Survey, Texas groundwater and Ogallala studies.