In a guest editorial in the Jan 30 Sentinel, Mike Rotkin responded to an editorial that I co-wrote with Paul Gratz and David Stearns. Mike wrote, “I was frankly shocked at the willingness of the authors…to mislead readers with fear-based misinformation that they know all too well is inaccurate or distorted at best.”
And I hope after reading the following you might be persuaded that I’m not trying to distort the facts. I think part of our disagreement stems from facts that have changed since you arrived at your decision that desalination is warranted. Here’s what I invite you to consider:
The 2003 Integrated Water Plan (IWP) predicted that a worst-case drought in 2010 would require summer curtailments of 39%. That figure was based on an estimated water demand in 2010 of 4.8 billion gallons. Actual demand in 2008 was much lower— 3.6 billion gallons, the figure the Water Department now uses as representing current demand. In 2009 and 2010 use was even lower, probably close to 3.1 billion gallons. Current demand (2008) is only 6.5% more than what our water supply would be in a worst-case year (IWP Table II-1). This achievement of lowering water demand has resulted in far greater water savings than could be provided by a desalination plant, which in a worst case year would provide 450 million gallons of water during peak season.
Another way to look at this achievement of lower water demand is the status of Loch Lomond Reservoir. On Oct 1 of 1975 the reservoir was at 60% capacity. Allowing the lake to drop to that level in a normal rainfall year proved imprudent, since the following two winters were extremely dry. Contrast that with the Oct 1 level in 2008 of 84%, and 2009 and 2010 of 90%. Our lower water demand has resulted in a high degree of drought protection. The difference between 84% full and the 1975 level of 60% full is 670 million gallons. If 84% is made the goal, then even accounting for evaporation and fish release, there would be significantly more water available in a 2nd year drought than a desal plant would provide.
Your article indicated that the brine disharge issue is “completely resolved”. I agree that diluting the brine with waste water is an effective solution for now. However, in my vision of the future, Santa Cruz will carry out an effective campaign for every building to install .8 gallon-per-flush toilets and low flow shower heads. This will result in reduced waste water, making today’s calculations about brine dilution obsolete. In the 2008 Settlement Agreement with UCSC, the City acknowledged that it plans to expand the desal plant in the future, “The parties agree that … Phase Two (and subsequent phases) would be implemented to accommodate future growth in system demand.” This means that the current plan to dilute brine will not suffice. Another problem is that diluting brine with treated wastewater forecloses the use of that wastewater for other purposes. As regulations in California change, we may have more opportunities to use the wastewater.
You state that the problem of killing marine organisms “has been solved by the design of a low-volume, slow intake that will have no significant impact on marine life”. The volume of seawater intake is projected to be roughly twice the volume of desalinated water. That means that Soquel Creek operation of the plant will suck in 3 million gallons of seawater a day, 365 days a year killing anything smaller than 2 millimeters. That’s almost all fish eggs and larvae, as well as plankton. Where is your source for concluding that this impact is not significant? Are you considering the cumulative impact of other desal plants planned for Monterey Bay?
Your conclusion that exchanging water with other districts “might help other districts, but nobody has surplus water to share with Santa Cruz” does not take into account that an agreement could be established whereby Scotts Valley and Soquel Creek Districts provide water to Santa Cruz during drought years. Those districts could agree to match the drought curtailment levels of Santa Cruz, e.g. 15% summer curtailment, and send the 15% of their normal summer production to Santa Cruz. I appreciate your acknowledgment that water exchanges could help other districts. Soon we will have figures from the County that show the amount of surplus winter water that could go from Santa Cruz to neighboring districts. Soquel Creek District pumps 17% more from the Purisima Aquifer than its consultant considers a sustainable yield. With figures from the County, we’ll see how much of that over-pumping could be alleviated with water from Santa Cruz.
You mention a “plan to build sufficient alternative energy capacity, e.g. solar on virtually every city building, to offset the proposed plant’s energy demands”. Let me offer an analogy as a way to think about this. A doctor tells a patient, “The extra weight that you are carrying could kill you. You need to reduce your intake of calories.” The patient responds by reducing calories in the morning only to add an extra slice of cheesecake at dinner. What I’m trying to point out here is that to avoid sea level rise of “a couple of yards in this century and several more in the next century” [James Hansen, NASA] society can’t merely offset our additional appetite for fossil fuels. We need to reduce it. The California goal is 80% reduction by 2050. All those solar panels are needed to reduce our current fossil fuel energy consumption, not feed a new energy habit.
The need to share water with native fish will require us to improve conservation. In fact, state law requires that we reduce our per capita water consumption 20% by 2020. In addition to the toilet and shower improvements I’ve mentioned above, we need to take advantage of the enormous potential of graywater and rainwater to irrigate the landscape, as well as the need for landscape plants that are drought-resilient. Please take a look at Soquel designer, Bobby Markowitz’s web page for examples of landscapes that include graywater and rainwater, http://www.earthcraftdesign.com/
Looking forward to future dialogue,