Wild Atlantic salmon in Maine, rainbow and brook trout in Wisconsin, brown trout in Minnesota and fall-run Chinook salmon in California share something in common: each is threatened by groundwater pumping.

The environmental consequences of groundwater pumping are catastrophic: rivers, springs, lakes and wetlands have dried up, the ground beneath us has collapsed, and fish, birds, wildlife,

trees and shrubs have died. Yet, the only people who know about this problem are a few scientists, a handful of water management experts, and those unfortunate enough to have

Alas, the situation is getting worse. In the ongoing drought, cities, farmers, miners and individual homeowners, in search of new water supplies, have mostly turned to groundwater. Once thought to be as ubiquitous and plentiful as the air we breathe, we now know that groundwater is a finite resource, one that we are quickly and recklessly depleting.

To understand this pressing threat to some blue-ribbon trout waters, it’s necessary to understand a bit of the science of hydrology. Ground and surface water are intimately connected in the hydrologic cycle. Rainfall and snowmelt indirectly provide water to lakes and rivers by percolating into the ground and then migrating laterally to reach a watercourse.

If this sounds strange, consider the following riddle: where does water in a river come from if it has not rained recently?

It comes from groundwater. The onset of groundwater pumping disrupts this cycle by creating a “cone of depression” – a lowering of the water table in the vicinity of the well. If pumping continues, the cone may eventually grow so large that the well starts capturing water directly from the river. Even if the well is located some distance from the surface water, it indirectly causes harm by intercepting water moving toward the river.

Legal rules compound the problem by failing to limit the size and scope of groundwater wells. Imagine a groundwater aquifer as a giant milkshake glass, and each well as a straw in the glass. In most states, the law allows a limitless number of straws in a single glass. It’s a classic example of the tragedy of the commons, and it’s a recipe for disaster.

For trout anglers, the need to reform the system is urgent. Because groundwater moves slowly, years or even decades may pass before groundwater pumping lowers the flow in a river, reduces the level in a lake or increases the ambient water temperature. The hidden tragedy is that groundwater pumping that has already occurred will harm trout streams in the future. And as groundwater pumping increases, the consequences will become more severe.

Farming, ranching and rapid development consume massive quantities of groundwater in the West. But the problem isn’t confined to any one region of the country. Even relatively “wet” states like Massachusetts, Florida, Michigan, Wisconsin, California and Minnesota consume unsustainable amounts of groundwater to support population growth, suburban sprawl, a consumer craze for bottled “spring” water and the fast food industry’s demand for perfectly uniform French fries. What can we do about this problem? Lots. We can get involved with a local group, such as a Trout Unlimited chapter. At the state level, we can break the relentless cycle of unlimited access to finite groundwater resources. Economic incentives can be a powerful tool to stimulate conservation and to reward those who conserve water with the right to sell some of it. Developers can be required to purchase and retire existing water rights. Simply put, we can no longer afford to allow unlimited new straws in the milkshake glass.

Finally, we must recognize the economic value of our water resources. Although water is a precious commodity, millions of Americans pay more each month for their cell phone and cable television than they do for water. In fact, most Americans pay nothing for the water that they receive. Most water bills simply charge for the costs of the distribution of the water. Increasing the price we pay for water would encourage conservation and reduce the pressure to drill new groundwater wells that threaten some of our favorite trout waters.

with permission of Editor and Robert Glennon.

Glennon is the Morris K. Udall Professor of Law and Public Policy at the University of Arizona College of Law.

Learn more about ground water and French fries in his excellent book, “Water Follies:

Groundwater Pumping and the Fate of America’s Fresh Waters,” Island Press, 2002.