So whose water is it anyway? (On First Reading).

It used to be that farmers in the West battled cities for water.

Now farmers in Colorado are fighting other farmers, and their urban allies, over continued pumping of wells that are draining water supplies from the South Platte River, northeast of Denver. Like most other Western states, Colorado adheres to the "first in time, first in right" water doctrine, which decrees that the first user of water has a senior right to continue using that water over subsequent users.

It's relatively simple when the water in question is from streams. Everyone can see the effects of one's use. But when underground water that is connected to the surface enters the mix, it becomes a bit murky.

After the Great Depression, Colorado farmers began sinking wells along the South Platte River as insurance against the drought spawned by the Dust Bowl years. Few knew there might be a connection between surface and groundwater. During times of water surplus everyone had their fill.

But with the current drought in Colorado and much of the arid West and High Plains states, there's not enough to go around. More than 3,000 wells from 1,500 farms are reducing flows in the South Platte. A coalition of irrigation districts and cities along Colorado's Front Range sued the well owners. A state water court ruled in December that the court, not the state engineer, has authority to allocate water in the area. The potential effect--1,500 farms going dry.

Colorado Attorney General Ken Salazar is heading discussions among water users and has appealed the decision to the state Supreme Court. The chair of the legislature's Joint Budget Committee, Senator Dave Owen of Greeley (a community at the head of the South Platte River valley) is developing legislation to resolve the dispute.

His legislation would require the state engineer to adopt rules for groundwater use in the river valley and approve plans to replenish surface water flows by well owners. Those not in compliance would have their supplies cut off.

The surface water/groundwater conundrum has implications for other western states. Kansas successfully sued Colorado over unregulated pumping of wells that affected the Arkansas River in southeastern Colorado, which resulted in lower stream flows into Kansas in violation of an interstate compact. But no one wants 10 years of litigation again, and in Colorado's case, more than $10 million in legal costs and nearly $30 million in penalties.

Kansas Representative Carl Holmes notes a difference between Kansas water law, which requires all water users-surface and underground-to obtain a state permit, and Colorado's split court-and agency-administered system. "We've required permits for all but domestic water uses since 1945, have enforced them since the 1960s, and have metered wells in groundwater management districts to measure water use," says the chair of the House Utilities Committee.

Kansas and other states will be watching whether Colorado's dispute can be resolved through negotiations and legislation, or whether the courts will determine the winners and losers.