Greg Garland would really like a swimming pool. But not just any old swimming pool.

If the chairman and former chief executive of Phillips 66 has his way, a stretch of the South Llano River on his ranch 150 miles west of Austin would be dammed for “recreational purposes.” That, he’s hoping, will hold back enough water to create a private, 3.9 million-gallon swimming hole.

That amount of water would fill up the capital city’s historic Deep Eddy pool six times over.

Local residents and environmental groups are not having it. They say Garland’s plan, submitted through an LLC he controls, threatens to deplete the supply of drinking water and damage the environmentally sensitive, clear-water river that’s a popular destination for kayakers, anglers and swimmers.

Linda Fawcett, president of the Llano River Watershed Alliance, said Garland’s plans could jeopardize the livelihoods of locals who depend on tourism and the area’s ecosystem.

“It’s a horrible idea,” she said. “This is, for so many reasons, wrong.”

Opponents say proposed limits on how much water could be retained under drought conditions don’t go far enough, and they plan to air their concerns at a public meeting Thursday hosted by the Texas Commission on Environmental Quality, which is responsible for issuing a permit.

Phillips 66’s press office declined to comment or to make its chairman available for questions. Efforts to reach Garland by phone and email weren’t successful.

The plan to limit water flow on the South Llano seems particularly egregious to opponents as Texas suffers through record heat waves and a lack of rainfall that has left more than half the state in at least “moderate” drought conditions. The river is flowing at about 30 cubic feet per second at a USGS monitoring site in Junction, Texas, about 40% below its historic median.

The TCEQ’s members are appointed by Texas Governor Greg Abbott. Garland has donated $10,000 to his campaign funds since 2021.