I met James Bentley when he introduced himself after a forum “Desalination and the Alternatives” held at Live Oak School in March, 2010. He told me that he recently retired from the Santa Cruz Water Department, where he was Superintendent of Water Production since 1994. “Do you know about the water transfer concept?” he asked me. I had never heard of it.
When we got together afterwards, Bentley explained that in 2000, the City’s consultant, Carollo Engineers, recommended a plan whereby Santa Cruz would supply water to Soquel Creek Water District during normal winters. The District would transfer water back to Santa Cruz in the summer of critical drought years. Bentley told me that the reason the City did not pursue this strategy was that it involved applying to the State for water rights revisions, potentially opening up a Pandora’s Box of water rights troubles. Since 1998 the City’s water diversion from Laguna Creek on the North Coast had attracted the attention of National Marine Fisheries Service (NMFS), the agency charged with enforcing the Endangered Species Act. The City regularly dried up Laguna Creek in the summer months, making it unsuitable for fish habitat.
Since that time Pandora’s Box has opened wide, but not because Santa Cruz pursued the water transfer strategy. NMFS and California Department of Fish and Game are asking Santa Cruz for large reductions in summer diversion from the North Coast streams and San Lorenzo River. Santa Cruz’s water rights are being re-written. So now’s the time to re-write them in a way that allows beneficial regional collaboration.
The road to drought security for Santa Cruz runs through its neighbors’ back yards—or more precisely, through the underground aquifers it shares with its neighbors: the Santa Margarita Aquifer (beneath the San Lorenzo River Watershed) and the Purisima Aquifer (beneath Live Oak, Capitola, Soquel/Aptos). According to a 2011 Kennedy/Jenks study on regional water transfers commissioned by Santa Cruz County, the City could “bank” water in the aquifers during normal winters by sending river water to neighboring districts. This winter water would recharge the aquifer through percolation ponds and/or injection wells. It also would supply water customers in those districts with City water during winter months so that the districts could reduce groundwater pumping. According to Kennedy/Jenks, “Santa Cruz should be able to purchase the banked water during periods of drought”.
Water transfer is very appealing for Soquel Creek Water District, which is 100% dependent on well water from aquifers that are over-pumped to such a great extent that salt water from the ocean is moving inland. Water transfer is a win for Scotts Valley, since that district has also overdrafted its groundwater—by as much as 200 feet in some places. And it is a win for the fish, since when groundwater is restored to higher levels, more water moves into the streams during summertime when juvenile fish need ample water flow.
County Water Resources Director, John Ricker, is currently running a study to determine the potential yield of the water transfer program, including how much water Santa Cruz could get back from the neighboring districts during times of drought. The potential for aquifer recharge appears highly promising, according to river flow records of the past 74 years. The median flow in the San Lorenzo River from mid-January through mid-April runs over 100 cubic feet per second. Santa Cruz currently diverts less than 5% of the flow during those months. This means that enough additional water could be diverted without harm to fish migration to supply all of Scotts Valley and Soquel Creek Water District needs for several winter months and in addition to water for direct recharge of the aquifer. (Migrating fish need flows of 100 cubic feet per second to swim up the river’s gorge between Santa Cruz and Felton. Since the Santa Cruz diversion is downstream of the gorge, diversion at that point does not impact winter migration.)
The principal challenge to regional water transfers is securing the needed water rights revisions. That means that the state and federal fisheries agencies need to be involved in shaping the water transfer strategy. The gain for fish is obvious, since the more well water Santa Cruz can receive from its neighbors during drought years, the less it will draw from streams where juvenile fish need the flows. The question is whether the City of Santa Cruz will perceive that its own water security is tied up with that of its neighbors. The Soquel Creek Water District recently asked Santa Cruz to apply for an emergency water rights permit to begin transferring water immediately. We hope the City will respond affirmatively.
Although regional collaborations offers the promise of drought relief to Santa Cruz, there is one thing that it doesn’t offer the City: water for growth. The County’s purpose in facilitating inter-district transfers is to restore overdrafted aquifers and streams, not provide water for growth. The County’s work plan assumes that “future demands in the targeted service areas will not increase.” That means in order to participate in water transfers, the City Council will need to pass a water-neutral development policy, something they have begun to formulate for the UCSC campus.
Desalination, on the other hand, has always been intended as a water source that can supply City growth. According to the 2003 City document that named desalination as the preferred option, “The purpose of the City of Santa Cruz Integrated Water Plan is to respond to the current drought-related crisis and plan for future growth.” This may explain the enthusiasm of some people who back desalination in spite of its energy intensity and price tag that has quadrupled since City approval in 2005.