ACWA conference notes connection between land use and water

A full-day session November 29, 2005, to kick off the Association of California Water Agencies conference in San Diego November 29-December 2 addressed the connection between water and land use.

“Water Resource Management and Growth: California at a Crossroads” brought together land use planners, hydrologists, hydrogeologists, engineers, water purveyors and local officials to discuss the integration of water resources planning and management with land use planning. The session also addressed methods to meet new legislative and planning challenges.

“This is one of the top issues facing the water community and facing the state of California,” said Steve Hall, the executive director of ACWA.

The type of land use carries a corresponding water need whether that land be agriculture, residential, commercial or open space preserve. Court decisions about the sufficiency of environmental impact reports have created uncertainty about future water supplies, and one California Court of Appeals decision puts existing water supply in doubt. “There is a growing frustration across the state among our members about the need to move forward,” Hall said.

While the conversion of agricultural property to residential parcels means growth, it also reduces agricultural water use and thus has some offset. The agricultural sector is the largest user of the state’s water, accounting for approximately 34 million acre feet in 2000. Some decline in that figure is predicted by the year 2030.

Not all of that predicted reduction is due to land development. Shifts to less water-intensive crops and irrigation efficiency also account for some of that anticipated reduction. That creates the possibility of water transfers and basin recharge in some areas of the state.

In other areas of the state, the conversion of agricultural land to housing will increase water use. The lower cost of inland property as well as available land means that growth is likely to take place in hotter and arid areas, which often require more water consumption. Between 2000 and 2003 new construction increased by 87 percent in Southern California’s Inland Empire, 92 percent in the San Joaquin Valley and 80 percent in the Sacramento Metro area. “It’s the allure of a single-family home that is partly driving that,” said Ellen Hanak, a research fellow at the Public Policy Institute of California.

The numerical predicted population increases between 2004 and 2030 include an additional 2.5 million people in the Inland Empire, 2.5 million in the San Joaquin Valley and 1.5 million in the Sacramento Metro area. The South Coast area is expected to grow by 3.0 million people, the Bay Area is anticipated to gain another 2.0 million people and other areas of the state are expected to increase in population by 0.75 million.

“That’s a substantial pressure on supply in the region,” Hanak said.

The California Water Code requires all urban water suppliers to prepare urban water management plans and to update those plans every five years. Those plans identify regional demands and supplies over a 25-year planning horizon and also provide documentation of water supplies which complies with recent state legislation requiring proof of sufficient long-term water supply for large subdivision approvals. Approximately 420 such plans, covering approximately 98 percent of the population, are expected to be delivered to the state Department of Water Resources.

While 84 percent of the management plans submitted included detailed information on water supply through 2026, only 47 percent included a housing profile which differentiated expected single-family housing demands from anticipated multi-family housing while only 58 percent of the included both supplies and uses.

California averages 23 inches of precipitation per year, which is a statewide average and not necessarily reflective of individual regions. That provides the state with 192.2 million acre feet per year, and Colorado River rights add 7 million acre feet. However, evapotranspiration causes the loss of 61 percent of that supply, or 121.6 million acre feet. Water dedicated for groundwater recharge, surface water flows, and environmental uses leaves 28.4 million acre feet per year for human consumption. Recycling and desalination increase that total to 41.2 million acre feet.

The average annual water demand in the state is 42.6 million acre feet, which consists of 33.8 million acre feet for agricultural use and 8.8 million acre feet for urban use. That in itself creates a deficit of 1.4 million acre feet, but other differences may increase that total. While 71 percent of state runoff occurs in Northern California, Southern California accounts for two-thirds of the demand. In a wet year the supply exceeds demand, but in a dry year there is a shortfall of 18 percent. Seventy-five percent of precipitation occurs between November and March with half of the year’s precipitation falling between December and February.

All State Water Project supplies pass through the Bay Delta, which creates a transport bottleneck. Various court decisions may decide whether the California Water Quality Control Board has jurisdiction over surface water for groundwater recovery, in which case a separate permit might be required for each well. Water rationing with cutback percentages is no longer considered a viable tool, as it penalizes those who have already been efficient in water use.

The Department of Water Resources has no enforcement authority over an urban water management plan. “We review it to make sure that everything required by the law is in the plan,” said David Todd, DWR’s chief of financial and technical assistance.

There is also no penalty for not submitting a plan, although a plan may be of assistance when applying for state or other grants. The risk of submitting a plan is that the water agency becomes vulnerable to lawsuits challenging the plan’s adequacy. In one case a court threw out the Santa Clarita environmental impact report because pertinent information was in an appendix rather than in the primary body of the EIR. Plans have also been overturned because speculative or uncertain water supplies have been included in the adequate future supply.

Another court case ruled that Lake Arrowhead’s pre-1914 water rights to the lake did not apply to residential use, and the Endangered Species Act has been interpreted by courts to include the use of water supply. “I think we’ll probably see more ESA challenges in the future that are going to impact water supplies,” said Jill Willis, an associate for the law firm of Best, Best and Krieger.

Land use issues also include desalination facilities and siting for plants. “It’s not just about growth,” said Jeff Loux, the director of the land use and natural resources program for the University of California Davis extension.