From the top of Newell Creek Dam, the water level of Loch Lomond Reservoir looks particularly low. Steep, gravely banks stretch between the trees and the water.
On one side of the reservoir, a crane and a drilling rig sit on floating docks, surrounded by shipping containers and other heavy machinery. The City of Santa Cruz is replacing the pipeline that brings water in and out of Loch Lomond. But the project managers worry that if the water level drops much lower, the construction equipment could get stuck.
After two dry years in a row, Loch Lomond sits at just under 60% full. The reservoir is the only major water-storage site for Santa Cruz, and it holds about a year’s worth of water when full.
“We never want to use it all, because we don’t know what that next year is going to bring,” says Heidi Luckenbach, deputy director of engineering with the City of Santa Cruz Water Department. “So we’re always hedging our bets against what the demand is and what the weather patterns are going to look like.”
Across the county, water management agencies are preparing for increased droughts and the challenges of climate change. Various climate models differ on whether our area will get slightly wetter or drier with rising temperatures. But they have one prediction in common: greater extremes.
Dry years will be drier. Rainfall could come all at once in a few large storms rather than spread across a season.
“We have to be ready for variability,” says UCSC Professor of Earth and Planetary Sciences Andrew Fisher. “It’s in the record. It’s here now—we see it. And the models predict it. They all say it is extremely variable year by year, within a year, decade by decade.”
Santa Cruz County is the second-smallest county in California by area, but its diverse geography—from redwood-shaded rivers to marshy mudflats—makes it one of the most complicated when it comes to water.
“We are not connected to the big California water system,” says Fisher. “We are off the grid. We’re gonna have to figure this out on our own.”
Several of California’s large counties share the same huge groundwater basins—underground aquifers that store water. In contrast, Santa Cruz County’s water is fragmented across three small basins. Each area faces different challenges.
With this in mind, water managers are designing and implementing projects to capture, store and access clean water. Some irrigation for crops in the Pajaro Valley might soon come from lake water rather than groundwater. A project in Soquel will use recycled water to replenish a groundwater basin. Another project in Santa Cruz will inject excess runoff from winter storms into wells.
“A project that might be hugely beneficial in Watsonville may not have any benefit, or have minimal benefits, up in Scotts Valley,” says Sierra Ryan, the interim water resources manager for Santa Cruz County. “Because they’re just completely different. It’s not just the habitats—the geology is completely different.”
Several of the water agencies in the county collaborate, but “we have to treat each situation independently, and make decisions on a hyper-localized basis,” says Ryan.
The decisions might be hyper-local, but they’re anything but small.
“We have not seen water supply projects of this scale since the Newell Creek dam went in in 1960,” says Ryan. She emphasizes that these infrastructure projects are the only serious way to prepare for the future.
“This isn’t something that we can conserve our way out of,” she says, adding that residents have already done a great job. “We have some of the lowest water use in the state.”
In 2018, California established a goal of 55 gallons per person per day by 2025 and 50 gallons by 2030. In Santa Cruz, the average is already in the mid-40s.
“It’s really remarkable what the community has done, but it’s not going to be enough,” says Ryan. “What we need to see is these big water-supply planning projects. And they’re underway now.” She expects the community to start seeing the benefits within the next five years.
From the Ground Up
One major determining factor in what sort of project will work for an area is whether the community relies mostly on groundwater or surface water. Groundwater, as its name suggests, comes from underground aquifers. The water gets pulled up through wells. Surface water is diverted from above-ground sources such as rivers and lakes.
In Santa Cruz County, one major problem with relying on surface water is storage. To take advantage of storms and make it through droughts, it’s necessary to have a way to capture and store runoff before it flows to the ocean.
Relying on groundwater comes with its own set of challenges. If over-pumped, aquifers tend to refill extremely slowly. And if they’re near the coast, saltwater can seep into the empty space.
This contamination—called seawater intrusion or saltwater intrusion—can ruin enormous areas of land and prove difficult to reverse.
Local agencies have explored several options for sustainable water management—the Pajaro Valley Water Management Agency alone evaluated 44 different programs. But a few main strategies underlie most of the current projects: transfer water seasonally, capture and inject water into aquifers or increase storage.
“There’s one that is referred to as “in-lieu” recharge, which basically means you rest wells and use the excess [surface] water in the winter,” says Gail Mahood, a retired Stanford geologist and president of the San Lorenzo Valley Water District. “In the winter, there’s way more water coming down the creeks than we could ever use. But we don’t have any place to store it, so it just goes out to the ocean. We could create inter-ties where we brought water up from Boulder Creek or from Fall Creek and Felton and in the winter, when we have plenty of it, send it to Scotts Valley, to our south system. And that way, they don’t have to pump during the winter.”
One inter-tie—essentially a large pipe—already exists between the San Lorenzo Valley and Scotts Valley water districts. But it’s only ever been used during emergencies.
“For us to routinely send water, even within our own water district, from Felton to Scotts Valley, we have to change our water rights. And we are in the process of that right now,” says Mahood.
Santa Cruz, almost entirely reliant on surface water, is also exploring water transfer options.
On the opposite end of the county, the Pajaro Valley Water Management Agency works towards a similar goal of resting wells.
“Our approach has been to deliver these supplemental water resources to farms along the coast,” says Brian Lockwood, the agency’s general manager. “So they can use water that the agency produces—for example, recycled water—instead of pumping their wells as much.
The agency also diverts surface water from Harkins Slough when they can. A new similar project called the Watsonville Slough System Managed Aquifer Recharge and Recovery Project would divert freshwater during high-flow winters to underground aquifers.
Putting water back into the ground poses more technical challenges than simply using runoff or recycled water in lieu of groundwater. Injecting water could change the chemistry of the aquifer and alter water composition.
But the effort is worth it for Santa Cruz, where storage space is limited, and Soquel, where seawater intrusion threatens the integrity of groundwater.
After extensive modeling to understand the underground aquifer system, Santa Cruz will test a program this winter called the Aquifer Storage and Recovery project. The water agency will treat excess surface water during the winter and use a well to inject it into the groundwater basin.
“We will use the four existing wells and then add to it up to four, or even six, wells to recharge the mid-county basin, and then extract when we need it,” says Luckenbach.
The demonstration was originally scheduled for 2023, but the city collected enough data and advanced the project to help manage water in case the current drought continues. The city plans to implement the entire project over the next five years.
The Soquel Creek Water District also plans to replenish its groundwater basin in a project called Pure Water Soquel. Soquel Creek’s groundwater basin was categorized as critically overdrafted by the state and is in danger of seawater intrusion.
“Replenishing, creating a hydrologic barrier, is the proven method,” says Ron Duncan, the general manager at Soquel Creek Water District. The agency will treat recycled water to drinking standards before putting it back into the ground.
“The locations were strategically chosen by a hydrologist to halt seawater intrusion,” says Melanie Schumacher, the special projects communications manager at the district, adding that the district has worked closely with the community to determine which project best fit the goals and values of the residents.
“This is not a new technology—it’s been used all over the world and in California,” says Schumacher. “In fact, Disneyland has on their website that all the water they use is recycled.”
After approving the sustainability plan, the state used it as a showcase for other groundwater basins across the state.
In tandem with increased surface water use and injecting into aquifers, the Pajaro Valley Water Management Agency is also attempting to increase above-ground storage.
College Lake, about a mile from Watsonville, gets drained each season and farmed. The water agency plans to halt the drainage and farming and increase the capacity of the lake by 700 acre-feet—or over 325,000 gallons—of water.
“This last year, we pretty much only got two rainfall events. So it’s now more important than ever that we utilize those two rainfall events or whenever we do get rain to capture it, slow it, spread it, and sink it,” says Marcus Mendiola, water conservation and outreach specialist with the Pajaro Valley Water Management Agency. “We need to make sure that we’re developing infrastructure to utilize the rain when it does fall.”
To add to the growing number of projects, the Pajaro Valley Water Management Agency is also working with Andrew Fisher and colleagues at UCSC and the Research Conservation District of Santa Cruz County to encourage landowners to create groundwater recharge sites. The program creates an area for stormwater to flow to, where it then percolates into the ground. A meter measures how much water flows in, and landowners get a certain amount taken off their water bill.
“It’s effectively like running their meter backwards,” says Fisher. As far as he knows, the program is the first of its kind. He feels optimistic about it. So far, landowners like it, and so does the agency. But he keeps his expectations metered.
“Some of the projects will work better in some years than others,” he says. “Some projects may work better than planned. That’s great. Others may not work as well.”
The solutions to climate change and sustainable water systems, he says, will come in pieces.
Unfortunately, the pieces are pricey.
“These projects are really important. We absolutely need them to be able to maintain our quality of life here,” says Ryan. “They are going to be really expensive. And on top of them, a lot of the water infrastructure in the county is reaching the end of its useful life and is needing to be replaced or rehabbed.”
Replacing the main pipe from Loch Lomond and recovering from fire damage in the San Lorenzo Valley are two major examples. In addition to working around normal water operations—fixing the bike while riding it, as Heidi Luckenbach puts it—the agencies must operate under the strained conditions of the pandemic. The price of materials skyrocketed, crews shrank and protocols changed.
Some of the water agencies secured state or even federal funding for sustainability projects, but “people are going to see rates go up… There isn’t a way out of this that doesn’t involve large infrastructure upgrades,” says Ryan.
“One of the biggest misconceptions that I hear when I’m talking to the public is the idea that if we just stop allowing development, that somehow that would be enough to solve our water problems,” she says.
She emphasizes that population growth is not the main problem for the city right now. The state requires areas to take on a certain amount of population growth, and the new buildings use less water than single-family homes.
“In 2001, the state set out requirements for very large housing projects—over 500 units and large shopping centers, etc. And they had to demonstrate a long-term water supply availability before these projects would be approved,” says Ruth Langridge, a senior law and policy researcher at UCSC who specializes in land use, groundwater, climate change and drought.
In 2018, the state added that all urban suppliers, regardless of size, must provide water-shortage contingency plans and drought risk assessments. Langdridge says this policy spurred cities and counties to start addressing looming water shortage problems.
“Population [growth] will add a small number of people who are going to be using water, and they’ll be using that water efficiently in these new houses,” says Ryan. “It’s very low water use compared to when we have a dry year like this, we have a 60% reduction in our water supply in one year… The thing that we need to be concerned about is climate change.”
Larry Ford, natural resource management consultant and one of the creators of Friends of San Lorenzo Valley Water, agrees that addressing climate change is the solution. He has spent recent water district meetings discussing a surcharge for fire recovery. He worries that things will be much worse ten years from now.
“People really need to know that this is something that they need to pay attention to. This is not just some fad… it’s going to affect water supplies, it’s going to affect agriculture, it’s going to affect biodiversity conservation and all these other really important things in our daily lives.”
The droughts already affect biodiversity. In addition to preparing communities for a more sustainable future, these projects will also help threatened and endangered species.
“Santa Cruz County is home to dozens of aquatic species that rely on our rivers and streams,” says Ryan. Steelhead and coho salmon attract the most attention and are considered umbrella species—when their habitat needs are met, so are the requirements for most of the other species.
Ryan worries that this year might end catastrophically for the fish populations.
“We’re definitely seeing higher water temperatures and lower flows than are optimal at this time of year,” she says.
Usually, the county waits until the end of summer to check stream gauges, but they pulled a few out early this year to compare to years past. It doesn’t look good.
In the San Lorenzo River, the flow “might not be sufficient to sustain any of the fish born in the creek this year,” says Ryan.
As climate change intensifies and temperatures rise, evaporation from water sources will increase, and fish, as well as plants, will need more water to survive.
After the statewide drought declarations earlier this summer, some residents expressed concern that further reducing water consumption would make it impossible to grow food.
Cynthia Sandberg, the owner of Love Apple Farms in the Santa Cruz Mountains and a gardening teacher for 20 years, encourages people to give up on lawns but not gardens.
“Please still have a garden,” she says. “There are ways to do this with a lot less water than you think.”
A home vegetable garden, she says, uses about half the amount of water a lawn does, “but you can still reduce that in times of drought, probably by another 50%.”
She suggests mulching around plants with straw, cardboard, mulch, even plastic. Watering in the early morning with drip irrigation or by hand rather than with sprinklers further reduces evaporation. When she can, Sandberg also uses graywater that’s free of soap or cleaning products. And adding mycorrhizal fungi to roots helps plants absorb more water and nutrients from the soil.
“It’s a symbiotic fungus that attaches to the root system of the plant and grows along with the plant. And this starts to create a sponge-like mass around the root,” she says. “That sponge-like mass can actually hold and retain water, lessening the number of times you have to water and the amount you have to water.”
But even with several tricks for conserving water, she worries about long-term drought.
“When farmers can’t get the water they need, then we’re all going to be in big trouble,” she says.
With several large water projects ongoing around the county, one can hope the problem, at least for a time, will soon be dammed.