It sounds simple: Who owns the groundwater in Texas? But this issue, like others in the hot-button area of aquifer planning, is embroiled in an ongoing policy battle.

At a crowded hearing earlier this week, members of the state Senate’s Committee on Natural Resources heard testimony on a bill introduced by Sen. Troy Fraser, R-Horseshoe Bay and the committee’s chairman, that would declare that landowners have a “vested ownership interest” in the water beneath their land. A less-discussed second bill, filed by Sen. Robert Duncan, R-Lubbock, recognizes both landowner rights and the “compelling public interest” of effective groundwater management.

Both bills are part of a vigorous debate over the best way to manage the declining aquifers in this fast-growing state, where irrigated agriculture is a powerful political force. The conflict pits existing water users against prospective new users, and conservation-minded officials against businesses seeking to sell water.

The state is just concluding a first-of-its kind groundwater planning process, in which 96 “groundwater conservation districts” around the state detailed how much water they want to remain in their local aquifers 50 years from now. Hemphill County, for example, set one of the most conservation-oriented goals in the Panhandle: It wants at least 80 percent of its portion of the Ogallala Aquifer to remain available in 50 years.

Based on those plans, the Texas Water Development Board, the state’s water planning agency, is now in the process of telling the groundwater conservation districts — most of which are elected bodies — how much farmers, cities and other water users in their area can collectively pump each year. The districts then issue individual permits, which in effect carry the force of law.

Fraser said his bill, which has support from groups like the Texas Farm Bureau and the Texas Wildlife Association, would not affect the groundwater management process but would merely codify what most Texans take as truth: that landowners have a right to the water beneath their property. Opponents, however, fear it would hamper the new groundwater management process by allowing landowners who have never drilled a well before to sell their water rights to distant cities — and push back against officials who try to stop them.

Fraser’s bill would result in “uncertainty for all permit holders,” said Ronald Gertson, president of the Coastal Bend Groundwater Conservation District’s board of directors, who fears that rice and turf-growers in his area could be adversely affected.

The conservation planning process — initiated by the Legislature in 2005 — has already drawn legal challenges. Mesa Water, a company owned by T. Boone Pickens, the billionaire oilman, filed a lawsuit last year with a local rancher against the Texas Water Development Board. Mesa has bought substantial water rights in the Panhandle and hopes to one day sell water to big cities like Dallas — goals that conflict with Hemphill County’s conservation emphasis. While that is the only lawsuit, seven petitions — including one from Mesa — have been filed challenging how “reasonable” the 50-year plans of the groundwater groups are.

The biggest battle involves the Edwards Aquifer in Central Texas, whose managers have instituted some of the strictest conservation measures in the state. Landowners around Texas are eagerly awaiting a ruling from the State Supreme Court on a landmark case involving two farmers who wanted to draw large quantities of water from the aquifer but were allowed only a tiny amount by groundwater managers. Water law experts say the decision could roil the state’s groundwater planning process, which tries to balance the rights of landowners against the long-term conservation that is in the public interest.

Several dozen bills, in addition to Fraser’s and Duncan’s, have been filed on groundwater issues this session. But many water planners simply want closure to the process.

“If we could be successful in settling this this session,” said Jim Conkwright, general manager of the Lubbock-based High Plains Underground Water Conservation District, “I think it would go down as a landmark session.”