The exact source of the San Lorenzo River is elusive: It begins where towering redwoods in California’s Santa Cruz Mountains harvest water from storms and fog drifting in from the Pacific Ocean. The water drops penetrate deep into the absorbent forest floor and underground only to re-emerge later from coldwater springs. Gravity pulls the water over falls and cascades; other streams enter, and soon, a river is born. Frogs, turtles, salamanders, kingfishers, cougars and many other species depend on the San Lorenzo. The flowing water carries dissolved oxygen and drifting insects into the mouths of hovering steelhead trout, and continues downstream to mix in a brackish lagoon before discharging and spreading sand into the Santa Cruz surf and the Pacific Ocean beyond.
On a spring day you can climb at Castle Rock near the top of the San Lorenzo River watershed, mountain bike or hike down numerous forest trails, kayak a whitewater gorge, and surf near the river’s mouth. It’s not surprising that, for centuries, people have moved to this piece of paradise where the mountains and a river meet the sea. But as the human population of this region has grown, a shallow undercurrent threatens it all.
The San Lorenzo appears to have recently been the southernmost coastal river in North America hosting the greatest diversity of Pacific salmon (chinook, coho, chum, pink) and steelhead trout. The river was an angler’s dream before Spanish missionaries came up the coast in 1769. Water diversion, logging, channel straightening,
urbanization, migration barriers, lagoon modifications and road-building over the last two-plus centuries have combined to devastate the watershed and eliminate all salmonid species except the more flexible steelhead trout, whose wild fate remains unclear.
Santa Cruz, a city of almost 60,000 people, surrounds the lower reaches and sandy outlet of the San Lorenzo River. Like so many other cities, Santa Cruz and the adjacent towns have reached, or exceeded, their water-use carrying capacity and are looking for ways to increase supply and protect against drought. Too much water is diverted from the San Lorenzo and adjacent streams, and this impedes the restoration of wild fisheries and other threatened species.
Presently, over-pumping of underground aquifers causes salt water to leach in from the sea and foul this important freshwater source. This same water story is told around our planet where less than one percent of all water flows fresh on the surface and underground.
How to solve the problem? Some officials in Santa Cruz and nearby Soquel propose construction of an expensive and energy-intensive desalination, or “desal,” plant that would convert 5 million gallons of ocean water per day into 2.5 million gallons of fresh water. This proposal has uncertain implications for the environment.
“If we end up not being able to bring in the water without harming sea life, I think this thing [desal] is dead,” Santa Cruz Mayor Mike Rutkin said in a recent interview. Disposal of the other 2.5 million gallons of potent brine adds to the complexity.
Others are proposing alternatives to desalination. Residents of Santa Cruz have already shown their ability to reduce their water use to about half of the state average and even more when droughts occur. Some local groups and individuals are pushing to take water conservation to the next level. They want to address the root causes of the shortage, increase the efficiency of the existing supply and to focus on expanding low-impact alternatives that have additional social and environmental benefits.
Rick Longinotti, with Transition Santa Cruz, says the city could require that all new development, such as that being proposed at University of California Santa Cruz, be “water neutral,” even if it means installing efficiency measures off campus in order to earn the use of those savings on campus. This kind of leadership would show a serious commitment to practicing what you teach.
Features of an upgraded water-supply system include: region-wide measures such as replacing inefficient fixtures, recycling grey water, droughtresistant landscaping, conversion to permeable road surfaces, rain harvesting, capturing storm runoff into wetland-like bioswales, diverting from streams during high flows (and not critical low flows in summer), expanding an existing reservoir and building groundwater recharge areas.
Implementing these and other projects could improve water quality in the river and ocean, provide natural flood protection, encourage biofiltration of pollutants, increase flows for wildlife, and create long-term and local jobs to design, build and operate these programs.
Surfrider® is encouraging individuals to start at home with their Ocean Friendly Gardens Program. State and local officials also need to update regulations that currently limit reuse of wastewater pumped to sea that could be reused for groundwater recharge, irrigation, landscaping and other uses.
Still, city and water district officials feel that without the desal plant, they may not be able to address the water needs of people and wildlife. The costs of building and operating a desal plant are not yet known, largely because extensive studies are trying to determine if it can be pulled off with minimal environmental harm. John Ricker, director of the Santa Cruz County Water Quality Division, noted that the desal plan may also die if it is not “… powered with alternative energy sources that don’t require burning more fossil fuels that contribute to climate change.”
Fifty years from now, the communities that have healthy watersheds, clean beaches, unpolluted surf, runs of wild fish, and innovative water supplies will be the ones that implement a bold, long-term vision now. Santa Cruz is just one of dozens of coastal cities with complex waterresource issues. Independent of whether the desal project lives or dies, one common quote you hear from almost everyone involved with California water is that when it comes to water efficiency, “We can do a lot more.”
Building a reliable, low impact and collaborative water future is critical. If that can’t happen in Santa Cruz, we’re all in trouble. For more information, visit the City of Santa Cruz and Soquel Water District’s Desalination Project, Transition Santa Cruz and Ocean Friendly Gardens Program websites.