Fresh water doesn\’t get used up in a global sense: that is, the quantity of fresh water on planet Earth doesn\’t change. But the way in which the world\’s fresh water is naturally distributed–by evaporation, precipitation, groundwater, lakes, and rivers and streams–doesn\’t always match where people want that water to be. The man-made systems of water distribution like dams, reservoirs, pipelines, and irrigation systems can alter the natural distribution of water to some extent. But the American West is experiencing a combination of drought that reduces the natural supply of water and rising population that wants more water. Even with drought, population pressures, and environmental demands for fresh water, there is actually plenty of water in the American Southwest–at least, if the incentives are put in place for some changes to be implement by urban households, farmers, water providers, and legislators.
For an analysis of the issues and options, a useful starting point is a set of three papers published by the Hamilton Project at the Brookings Institution:
- Melissa S. Kearney, Benjamin H. Harris, Brad Hershbein, Elisa Jácome, and Gregory Nantz, \”In Times of Drought: Nine Economic Facts about Water in the United States.\”
- Newsha K. Ajami, Barton H. Thompson Jr., David G. Victor, \”The Path to Water Innovation.\”
- Peter W. Culp, Robert Glennon, and Gary Libecap, \”Shopping for Water: How the Market Can Mitigate Water Shortages in the American West.\”*
Outdoor watering is the main factor driving the higher use of domestic water per capita in drier states in the West. Whereas residents in wetter states in the East can often rely on rainwater for their landscaping, the inhabitants of Western states must rely on sprinklers. As an example, Utah’s high rate of domestic water use per capita is driven by the fact that its lawns and gardens require more watering due to the state’s dry climate. Similarly, half of California’s residential water is used solely for outdoor purposes; coastal regions in that state use less water per capita than inland regions, largely because of less landscape watering . . .
\”Water infrastructure, by some measures the oldest and most fragile part of the country’s built environment, has decayed. … Water infrastructure—including dams, reservoirs, aqueducts, and urban distribution pipes—is aging: almost 40 percent of the pipes used in the nation’s water distribution systems are forty years old or older, and some key infrastructure is a century old. On average, about 16 percent of the nation’s piped water is lost due to leaks and system inefficiencies, wasting about 7 billion gallons of clean and treated water every day …. Metering inaccuracies and unauthorized consumption also leads to revenue loss. Overall, about 30 percent of the water in the United States falls under the category of nonrevenue water, meaning water that has been extracted, treated, and distributed, but that has never generated any revenue because it has been lost to leaks, metering inaccuracies, or the like … \”
As an example, developers could obtain a permit to build if they retrofitted existing homes with low-flow toilets. Residents of these homes welcomed the chance to get free toilets, and Santa Fe plumbers jumped at the opportunity for new business. Within a couple of years plumbers had swapped out most of the city’s old toilets with new high-efficiency ones. Water that residents would have flushed away now supplies new homes. … In short order, a market emerged as developers began to buy water rights from farmers. Developers deposited the water rights in a city-operated water bank; when the development became shovel-ready, the developer withdrew the water rights for the project. If the project stalled, the developer could sell the rights to another developer whose project was farther along. Santa Fe also enacted an aggressive water conservation program and adopted water rates that rise on a per unit basis as households consume additional blocks of water. Thanks to the innovative water-marketing measures, the conservation program, and tiered water rates, water use per person in Santa Fe has dropped 42 percent since 1995 …
Groundwater has been the saving grace for many parts of the water-starved West. Following the advent of high-lift turbine pump technology in the 1930s, many regions had access to vast reserves of water in underground aquifers that they have tapped to supply water when surface water supplies were inadequate. A recent study looked at data on freshwater reserves above ground and below ground across the Southwest from 2004 to 2013. It found that freshwater reserves had declined by 53 million acre-feet during this time—a volume equivalent to nearly twice the capacity of Lake Mead! The study also found that 75 percent of the decline came from groundwater sources, rather than from the better-publicized declines in surface reservoirs, such as Lake Mead and Lake Powell. Much of this decline occurred because some Western states, including California, have historically failed to regulate, or do not adequately regulate, groundwater withdrawals. As a result, groundwater aquifers are effectively being mined to provide water for day-to-day use. In response to the ongoing drought, California farmers continue to drill new wells at an alarming rate, lowering water tables to unprecedented depths …In the San Joaquin Valley of California, excessive groundwater pumping caused the water table to plummet and the surface of the earth to subside more than twenty-five feet between 1925 and 1977 …\”
Although not yet developed into a formal exchange, Arizona has been at the cutting edge in developing groundwater recharge and recovery projects and a supporting statutory framework to help enhance the reliability of water supplies. Arizona allows municipal users, industrial users, and various private parties to store water in exchange for credits that they can transfer to other users. Because water stored underground in aquifers is not subject to evaporation, groundwater that is deliberately created through recharge activity can be stored and recovered later. This recharge and recovery approach is facilitated by Arizona laws that restrict the use of groundwater in several of the state’s most important groundwater basins; these restrictions prevent open access to the resource. Restrictions on open access, combined with statutory and regulatory provisions that allow for the creation and recovery of credits, created the essential conditions for trade in stored groundwater. As a result, numerous transactions have occurred between various municipal interests, water providers, and private parties.