In the News

Why Fish Biologists are Plugging for Desal

By Jessica Lyons

Santa Cruz Weekly, 12/08/2010

During a rainy year—that is, a good year for fish—adult steelhead salmon swim in from the ocean and up the San Lorenzo River between December and March to lay their eggs in gravel on the river bottom. After hatching in early spring, the juvenile fish linger in the river for at least a year (and sometimes two or three), feeding and maturing. When they’re finally ready, the smolt, or teenage steelhead, head downstream into a lagoon, a sort of all-you-can-eat buffet for oceanbound young salmon.

“There’s a lot more food in the lagoon, and it helps them start acclimating to the saltwater,” explains Joyce Ambrosius, NOAA Fisheries Central Coast branch supervisor.

After the smolts’ physiologies have changed, allowing them to transition from freshwater to saltwater, they swim to the ocean, where they’ll grow into adults and eventually start the cycle all over again by migrating back to the river to spawn.

That’s during a normal, or wet, year. But things don’t run so smoothly when it’s dry, like it was in 2009, or even worse, like it was in 2007. During years like those, when the San Lorenzo River runs low, the city of Santa Cruz relies more heavily on water stored in Loch Lomond Reservoir, which gets its water from the Newell Creek watershed in the mountains at a point before the creek joins the San Lorenzo River in Ben Lomond. And as the water levels in Loch Lomond drop to slake the city’s thirst, so does the amount the water department releases into the final stretch of Newell Creek. The result: an even lower San Lorenzo.

“In the San Lorenzo River, when it gets to the dry years, the city of Santa Cruz has a hard time meeting the needs of the public for drinking water,” Ambrosius says. “They’re pumping as hard as they can and supplying as much water as they can for the public. That’s when it gets difficult, because there’s not enough water for the public, let alone the fish. There’s nothing that says how much [water] they have to release out of the dam for fish.”

Low river levels affect the amount and quality of fish habitat. Shallow waters are warmer, lower in oxygen and foster more algae. Low flows also harm migration; teenage fish can’t make it to the ocean to mature, nor can adult fish swim up the river to lay eggs.

As the city of Santa Cruz and the Soquel Creek Water District continue exploring plans to build a 2.5 million-gallon-per-day desalination facility in Santa Cruz—they’re hosting meetings about the project today, Dec. 8—the wellbeing of native salmon is emerging as an unlikely flashpoint in the debate. Human activity has wreaked havoc on coho and steelhead salmon in the San Lorenzo River and Soquel Creek. Altogether, environmental stresses have nearly obliterated the coho and drastically reduced the steelhead population.

NOAA Fisheries, the federal agency charged with enforcing the Endangered Species Act, says a seawater desalination plant will help the fish.

“There’s not enough flows in the river to meet the needs of the fish,” Ambrosius says. “We’ve been working with the city of Santa Cruz to develop a habitat conservation plan, and we really want them to include a desalination plant as part of the habitat conservation plan so more water is left for the fish. The sooner it can get online, the better.”

Not only is sooner better, Ambrosius says—bigger is better, too.

“This desalination plant may not be large enough to address the city’s needs, and it won’t address the needs of the fish,” she adds.

Federal scientists base this conclusion on modeling numbers from the city. But they say these figures, which project different flow releases for the fish with a desalination project, are still too preliminary to release.

“What we do know: The city gets water from the desalination plant during dry years and critically dry years,” says Ambrosius. “But [according to the models], sometimes during wet years, even with the desalination plant, there would still be shortages for fish … in certain streams.”

This argument puts Santa Cruz Water Director Bill Kocher in the odd position of having to defend his proposed project not because it’s too big or too energy-hungry or too unnatural—the usual critiques—but because it’s too small. While Kocher expresses some agreement with Ambrosius, he cautions that it’s too early in the modeling process to know for sure how fish would be impacted.
“Again, they lack—as we do—scientific evidence of exactly what will and won’t impact the fisheries,” he says. “I think it would be more fair to simply say: the less water taken, as far as they’re concerned, the better it is for fish. We believe with the size plant that we’re proposing, we can accomplish a lot of good for fisheries. But their first reaction to all that is, ‘Build it bigger.’”

Don’t Leave Me Dry
Fish need different amounts of water at different stages in their lives. “We want to make sure the fish are able to move up the creeks and rivers, and that the water is deep enough for them to make it past any migration barriers and get up the river,” Ambrosius says. “What we usually look for is half a foot to 9 inches depth.”

For spawning, fish need enough water to cover the spawning gravel so the eggs don’t dry out and die; water also carries oxygen to the eggs as it flows through the gravel. And smolt need in the neighborhood of 6 inches of water in the river in order to make it down to the lagoon and out to sea. All are part of why NOAA wants a bigger desalination plant.

Santa Cruz Deputy Water Director Linette Almond responds that while the basic purpose of the plant is for drought protection, “It’s certainly expandable in the future if we need to do that for any reason.”

Adds NOAA Fisheries biologist Jon Ambrose: “We know that they’re shooting for enough water to meet the needs of their customers, but meeting the needs of the customers doesn’t negate the fact that there will be current and future impacts to the fisheries with the city of Santa Cruz’s projected future growth.”

Transition Santa Cruz wants to save the fish, too. But desal’s not the answer, according to the grassroots group, which advocates increased conservation and a regional water swap instead of desalination.

If Santa Cruzans conserve at 2009 levels—57 gallons per day per person—or better, according to the group, this will achieve Oct. 1 reservoir levels of 90 percent, like Loch Lomond reached in 2009 and 2010. This, Transition Santa Cruz says, translates to 600-700 million gallons available in the second year of a critical two-year drought.

That’s what will save coho and steelhead, says Transition Santa Cruz’s Rick Longinotti.

“I’m disappointed in NOAA Fisheries’ position on the desalination plant,” Longinotti says. “I think that desalination represents the same kind of thinking that has wiped out the coho salmon, the same kind of thinking that does not pay attention to the long-range impacts of our actions. To worsen climate change in order to save native fish species seems counterproductive.”

Tackling Fish
Transition Santa Cruz’s anti-desal arm, called Santa Cruz Desal Alternatives (, plans to seek a referendum in 2012 requiring local water agencies to put a decision on desal to the voters, much like a successful ballot measure in Marin did on Nov. 2.

Voters may reject desal, Longinotti says, or the planned project may get stalled in court.

In a letter to NOAA Fisheries, the group outlines a host of measures it says would reduce water diversions and improve fish habitat. It’s also produced a video, Save Some Water for the Fish, now airing on community television.

Santa Cruz Desal Alternatives suggests limiting growth in water demand and implementing rebates for water-efficiency measures as well as requiring low-flow showerheads and dual-flush toilets.
The first measure the letter proposes, however, is a water swap. Soquel Creek Water District is 100 percent dependent on groundwater, while Santa Cruz is 96 percent dependent on surface water.
“The concept is for Santa Cruz to deliver water to Soquel Creek District in wet and normal winters, allowing Soquel to recharge their aquifer. In return, Soquel could deliver well water to Santa Cruz during droughts,” the letter says. “For example, if both districts curtail peak season water consumption by 20 percent, Soquel would be able to deliver 20 percent of their normal use to Santa Cruz. And with an aquifer that is recharged, the amount available to Santa Cruz during a drought could well be much higher.”

Additionally, the group proposes aquifer recharge using an abandoned quarry in Scotts Valley. Winter flows would fill the quarry, thus creating more base flow in Bean Creek, a tributary of the San Lorenzo.

The group also wants to see more conservation, which will increase water storage in the reservoir. “A modest additional conservation effort would allow Loch Lomond levels to remain high at the end of the dry season, thus insuring full refill of the lake during the winter months,” Longinotti writes. In the letter Longinotti explains that the water department uses an end-of-summer benchmark of 64 percent capacity for Loch Lomond to determine whether there’s a water shortage (if it’s at 64 percent or lower, a shortage is declared and conservation measures kick in). If the city set that benchmark higher, then Loch Lomond would be fuller in drought years and the city wouldn’t need to take so much water from the watershed. And, he writes, it’s highly doable. “In recent years, conservation by City water users has resulted in a lake level on October 1 of above 90 percent in 2010, 90 percent in 2009, and 84 percent in 2008. The City should make the conservation practice of the last three years the norm.”

In response, Dick Butler, NOAA Fisheries North Central Coast Office Supervisor, says his agency “supports any projects that result in water conservation, understanding that there is a point where no more conservation is possible. After that point, another water source must be made available or current water use must be dramatically changed.”

Butler says Desal Alternative’s solutions may help, and he encourages the group to pursue them. But he also says they won’t happen quickly enough to help the fish.

“The San Lorenzo River and Soquel Creek watersheds are in a severe overdraft,” he says. “Water diversions have resulted in major adverse impact to all life stages of salmon and steelhead in Santa Cruz County streams…Without a new water supply source, impact to listed species will continue. Therefore, we support the City of Santa Cruz’s pursuit of desalination as the best alternative for a new source of water supply.”

THE DESAL EIR SCOPING MEETINGS are Wednesday, Dec. 8, noon-2:30pm at First Congregational Church, 900 High St., Santa Cruz; and 6:30-9pm at New Brighton Middle School, 250 Washburn Ave., Capitola. For info visit


NOTE:  The City of Santa Cruz is mandated to release 1 cubic foot per second (448 gallons per minute) year round, 24/7.  This does not change in drought conditions.

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