Water Challenges Facing Soquel Creek Water District

Soquel Creek Water District serves 45,000 people in Capitola, Soquel and Aptos. Soquel Creek Water District is currently pumping more water out of the ground than can be recharged by rainfall.  If this practice continues, the aquifer will suffer irreversible damage. Unlike Santa Cruz, which relies primarily on surface water (streams), Soquel Creek District relies exclusively on pumping water from wells. Both aquifers serving the District are in a state of overdraft: the Purisima Aquifer, underlying Soquel, Capitola and northern Aptos, and the Aromas Aquifer, underlying Aptos and Rio del Mar.

The Aromas aquifer underlies the entire Pajaro Valley. Over-pumping in the Pajaro Valley has led to saltwater intrusion of the aquifer, forcing abandonment of coastal wells. Salt water intrusion happens when pumping reduces the water level in wells to a point near sea level. The natural flow of fresh water underground towards the ocean reverses. Gravity pulls sea water inland. Once a well gets polluted with sea water, it becomes contaminated for many generations, according to Ron Duncan, Soquel District Conservation Manager. Duncan is concerned that society has a history of poor self-restraint when it comes to overdrafting the water commons, noting that 60 percent of wells in populated coastal areas around the world have salt water intrusion.

On account of aquifer over-pumping by multiple users, the Soquel Creek Water District’s consultant concluded in 2009 that the sustainable yield of the Aromas aquifer for District use was zero. It is evident that the ability of Soquel Creek District to draw from the aquifer is linked to a sustainable water solution for agriculture.

In the Northern part of the District, the Purisima Aquifer is also in a state of overdraft. But saltwater intrusion has not yet polluted coastal wells beyond usable limits. Others pumping water from the Purisima Aquifer include the Santa Cruz Water Department, with wells in Live Oak, and private well owners.. According to a 2004 study¹, Soquel Creek Water District’s pumping accounts for 65% of the total pumping for the Soquel-Aptos area, (although the District has reduced its annual demand by more than 15% since that study was published). The District has considered putting a tax on private wells as a way to promote conservation. This proposal met with angry opposition at a Soquel Creek Board meeting. Some private well users came to the meeting armed and District staff summoned the Sheriff. In order to meter private wells and charge by the quantity of water pumped from the water commons, the District would need greater authority granted by the County. The District has thus far not sought this authority.

 A few years ago the District set a target for reducing pumping from both aquifers. The target was based on an estimate of sustainable yield from the aquifers in a 2004 consultant report.² The District lowered its water consumption by over 15%,  meeting the target in the last several years. Yet the District’s consultant reported in September, 2009, that water levels in District wells have not recovered3. District wells are still significantly below the levels that they need to be in order to avoid salt water intrusion. The consultant concluded that for the Purisima aquifer, in the northern part of the District, “revised sustainable yield goals would seem to be approximately 2500 acre-feet per year”. The consultant also noted that in the short term the District should pump less than the long-term sustainable yield target, in order to let aquifer levels recover to safe levels.

¹ Johnson, 2004
² Hydrometrics letter to Soquel Creek Water District, “Modeled Outflow to Achieve Protective Water Levels”, Sept. 2009
 

Pajaro Valley Aquifer Overdraft --- The Tragedy of the Commons

The history of unsustainable water use in Pajaro Valley reads like a textbook case of the “tragedy of the commons”. That term describes the cumulative effect of individuals acting according to a narrow, short-term self-interest. The “commons”, a natural resource used by all, becomes damaged beyond repair. Ultimately, this affects the interests of all. Currently in the Pajaro Valley, the negative consequences are not felt equally. There has been division among land owners and farmers regarding funding of solutions.

Any time the commons is threatened, the best solutions come from a community pulling together. People need to trust that their needs matter to others, particularly their need for a livelihood. In the Pajaro Valley, the solution may include the fallowing of farmland –periodic respite from water-intensive agriculture; greater investment in water saving technology; and land owners granting long-term leases to their tenants so as to encourage long-term investment. All of these solutions will have an economic impact. Should the community fail to unite around a solution, the county or state may intervene and impose a solution. A solution imposed by the state will only have the power to mandate reduced pumping. The more creative solutions such as fallowing depend on a local resolution.

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or continue to Part 3, Sustainable Water Solutions