Editor's note: This story has been updated with additional comments from Daniel Nix, the operations manager for Wichita Falls public utilities, who says the city's projections don't show it running out of water this year.

The Texas government keeps a list of a communities that could run out of water within 180 days. Most are small, affecting a few hundred or few thousand people. But now there is a big city on the list — Wichita Falls, near the Oklahoma border, home to more than 100,000 people.

Wichita Falls was added to the list last month when lake levels dropped to 40 percent and the city entered Stage 3 watering restrictions. Currently, residents can water only once per week, and city officials warn that the restrictions could tighten further sometime this summer.

At the end of the year, some projections indicate that the city "would not be able to pull any more water” from reservoirs, said Daniel Nix, operations manager for Wichita Falls public utilities. Nix said the utilities' projections do not show that the city will run out of water in the 180 days — most projections do not put them at zero water until some time next year. But Nix doesn't mind the 180-day designation, as it will help speed up the process of implementing planned conservation efforts.

The addition of Wichita Falls to the state’s high-priority list, which is maintained by the Texas Commission on Environmental Quality, shows that the drought continues to extend its reach. More than three-quarters of the state is experiencing drought, and weather experts expect little relief in the next few months. The TCEQ publishes a list of all water systems taking action to reduce water usage in response to the drought.

Wichita Falls will almost certainly implement Stage 4 drought restrictions by the end of summer, and perhaps as early as June, Nix said. The city has never before had to implement such harsh restrictions, and officials are currently revising the water restriction plan to decide what will be allowed. Most likely, Stage 4 will include no outdoor watering, no filling of pools and additional restrictions on car-wash businesses. Industrial users could also be affected, he said.

“This is one of those things where you plan and plan and plan and hope you don’t have to use the plan and find out where the weak parts of it are,” Nix said. With the restrictions on outdoor watering, he added, “all turf, trees, shrubs, flowers would have to die."

Nix is working with the TCEQ to create and implement a water reuse system that would treat wastewater to return it to the drinking water supply, hopefully by early next year.

Each of the more than two dozen communities on the 180-day watch list has its own plan to combat the drought, and the TCEQ supports them with information and planning, said Andrea Morrow, an agency spokeswoman. The list is based on data reported by the cities, which have varying amounts of resources and alternate water sources available.

“Each one is different," Morrow said.