In a city where a river once poured into the bay year round, a typical summer in Santa Cruz now leaves a dry imprint of the San Lorenzo snaking its way through Main Beach sand instead. Meanwhile, depleted aquifers are subject to saltwater intrusion and the city’s summer thirst also sucks away habitat for endangered fish upstream.
The development of a desalination plant to answer these environmental concerns is the subject of a contentious debate, dividing ocean advocacy organizations and environmentalists. Environmental Studies alumna Brooke Wright interviewed Environmental Studies ProfessorBrent Haddad, who recently completed a multi-year study of the costs and benefits of desalination in California.
From the Middle East to the City on the Hill, water is so universal and yet so precious that it facilitates wars, like the one between anti-expansion advocates and UCSC, or the one between the Santa Cruz Water Department and anti-desalination plant advocates.
Professor of Environmental Studies and Director of the Center for Integrated Water Research Dr. Brent M. Haddad has been following the city’s water shortage issues and thinks something can be done: desalination.
“As of today, this month, and the next six months, there's no crisis,” Haddad said. “(But) we are prone to extended droughts. We don't know when they will come but they do."
Climate change, Haddad said, may not only create more drought conditions through less rainfall but also lead to more fires, which are, of course, controlled by dumping water. Lots of it.
“If we have more fire prone conditions we might end up inducing a drought by putting out major fires with our city water supply during a heat wave,” he said.
So how does this potential crisis match up with the green lawns and full swimming pools we see throughout most of the year in Santa Cruz? Holding capacity. Santa Cruz only has limited holding capacity and short of building a reservoir, this isn’t about to change. So while there is enough water to water lawns and fill swimming pools now and through most summers, there is no way to store the extra water for any future extreme drought. And in the case of an extreme drought with so little holding capacity, the drained aquifers mean a rise in the risk of seawater contamination. Just like any system affected by gravity, when the water level in an aquifer located near the ocean drops too low, if seawater seeps in it’s like a levee breaking above ground: it infiltrates every nook and cranny of that system, poisoning the water. Santa Cruz, like other coastal communities, runs this risk every time it faces a severe drought.
“If you have desal it's like an insurance policy,” Haddad said.
The desalination plant being proposed by the Santa Cruz Water Department would serve as a buffer during times of drought by processing sea water and integrating it with fresh water supplies.
The Center for Integrated Water Research at UCSC researches fresh water issues and trains doctoral students in water systems and policy. Through state funding, the Center developed tools to guide California regions considering desalination.
"Wastewater as an alternative water supply is also promising. I have studied that as well. You have to look at each city and what its options are.” And for cities along the coast, like Santa Cruz, “the desal option should be taken seriously.”
The Santa Cruz City Council asked the Water Department to research desalination to manage those extreme drought conditions that, according to the Water Department and experts like Haddad, are bound to come up at some point.
“The prudent thing to do is to plan for droughts, and that's what water agencies do,” Haddad said. “So when Santa Cruz looked at its options, they decided that a desal plant was the best alternative.”
The report, which was signed by Haddad last July, looked favorably on the cost-benefit ratio of desalination but did not have a clear answer on the impact it would have on oceanic life.
“There is another set of costs that is difficult to quantify but should be considered in a balancing of costs and benefits of desalination….The location and configuration of brine disposal infrastructure influences its impact on ocean biota.” Page 6, Desalination Proposition 50 Final Report.
In addition, the place of intake, the report says, can be dangerous to sea life depending on the design. Finally, the energy required to draw seawater out and above sea level can be substantial, according to the report.
“Desalination by its nature is moving water upward, against gravity… There is an energy cost to lifting water.” Page 5, Desalination Proposition 50 Final Report
Another option is, of course, to do nothing, or rely on conservation.
“We use less today than thirty years ago with 30,000 more people. People are really efficient now,” Kocher said.
Haddad voiced the same sentiment: “We conserve more year to year than just about anywhere in California."
Short of a massive cultural shift, the only answer is to increase the supply. Not doing so, and forcing rations in the summer, may spell doom for the environment and the economy.
“If it's a mild drought you conserve your way through it. If it's a severe drought you have ecological, economic, and public health impacts. We can avoid those impacts if you invest in desal, and that's the choice.”
Environmental Studies doctoral candidate Tiffany Wise-West examines the WaterLab Reverse Osmosis unit as it is unpacked.
Ecological impacts begin even in moderate droughts like we had last year, when the streams and rivers that feed the Santa Cruz water supply were drained past the federal standard that the city was permitted to take. The city applied for and was granted a section 10 permit due to the shortage, which means fish and other species were put on critically low volumes of water.
“The reason it’s (desalination’s) not used in California is it’s a lot cheaper to drain our rivers and this has to change. We are going to have to do it differently,” Water Department Director Bill Kocher said.
Environmental concerns weigh heavily on both sides of the equation with conservation and ocean health on one side and endangered species and fresh water supply systems on the other. Additionally, there may be a cultural rift between anti-development advocates who envision widespread lifestyle changes, and those like Haddad who believe in ecologically beneficial technology.
“If you're trying to get to the movies and there's a parking lot, you’re going to take the nearest spots first. We've used up the readily useable water supply. We're using San Lorenzo river water, groundwater, and streams from the north coast,” which in Haddad’s example, was the short walk to the movies.
“Now we're trying to decide whether to do the longer walk stuff, and the closest now is desal, that's the shortest walk. Or you could go home and not see the movie.”
Not seeing the movie, it seems, is like not allowing full occupancy in the hotels during the summer.
“In a drought, who’s going to get fired first from the hospitality industry? It's the part-time, marginalized workers," Haddad said, noting that mandates reducing hotel occupancy rates are a possibility in the case of an extreme drought. “People don’t associate a desal plant with homelessness, but its these people who would lose their jobs if we had to cut back on occupancy to save water."
That concern is backed by Kocher, who said while the initial cost of building a plant is high, the cost of not building one may be higher.
“The economic impact of not having water in the summer is far far greater to these businesses than having water that costs a bit more,” said Kocher.
Somewhat ironically, building into upper campus at UC Santa Cruz may be the least damaging growth possibility for Santa Cruz to consider. Unlike tourists, students don’t need water in the summer.
To view the full report and learn about the Center for Integrated Water Research, visit http://ciwr.ucsc.edu/ and download the report at http://ciwr.ucsc.edu/UCSC_Desal_Prop_50_Final_Report.pdf.
