Surface Water Transfer

Key Issues:

Surface Water Transfer Concept has potential to be a long-term measure to diversify water portfolios and improve water management.
Surface Water Transfer Concept should not be considered an alternative to developing a new reliable and flexible supplemental supply.
There are several limitations and challenges that include the availability of water that could be guaranteed, water rights, and insufficient quantity to help restore the Soquel-Aptos groundwater basin.

The City of Santa Cruz is not presently able to transfer surface water to Soquel, but interregional exchange of water is currently being actively investigated by the water agencies as a long term measure to improve water management.

In May 2011, Santa Cruz County issued a report on the Surface Water Transfer Concept that included the preliminary assessment of transferring surface water from the City of Santa Cruz (City) to the Scotts Valley area (Scotts Valley) and Soquel Creek Water District (SqCWD). The report included preliminary calculations of potential volumes available for transferring as well as the benefits and limitations associated with this concept.

The Surface Water Transfer Concept outlines how excess winter flows from the San Lorenzo River could be treated at the Santa Cruz Graham Hill Water Treatment Plant and delivered to Scotts Valley and SqCWD for direct use instead of groundwater or for infiltration into the groundwater basin.

There are a number of challenges related to this water supply concept including:

1) the annual amounts that could be available for transfer are highly volatile, and the average of 340 acre-feet per year (afy) identified for SqCWD would only provide 18% of their supplemental supply objective (currently estimated at 1,880 afy) to restore the Soquel-Aptos groundwater basin to levels protective against seawater intrusion;

2) given the limited average yield, sufficient water could not be banked in the aquifers within SqCWD to address the City’s water shortage in the event of drought (estimated at 1,600 afy); and

3) permitting from fisheries resource agencies and the required amendment by the state to expand the allowed place of use under the City’s current water rights are far from guaranteed and could take up to 20 years before a transfer would be allowed.

The County of Santa Cruz will begin their second phase of the evaluation, to be funded by Prop 84 (Integrated Regional Water Management Planning Grant), with expected completion in 2012.

Should surface water concept be considered an alternative to desal?

"The County and the water agencies believe that exchanges of water between Santa Cruz and Soquel provide good potential for long term benefits for county residents and the environment, and we will continue to actively pursue those opportunities. However, many of these benefits will take many years to materialize, and would probably never offset the need for a supplemental water supply during dry years to meet both water supply needs and fish needs. In summary, while best practices of water resource management include maximizing the beneficial use of existing sources, the possibility of a water exchange is not a near-term solution to the water supply shortage faced by the City and Soquel Creek Water District and is not considered an alternative to developing a new reliable and flexible supplemental supply. "

John Ricker, Water Resource Division Director
Santa Cruz County Environmental Health Services

Status Report and PowerPoint Presentation

To access the County’s status report: http://www.scwd2desal.org/documents/Reports/Status_Report_SWT_May2011.pdf

To access the Powerpoint presented by John Ricker, County Water Resources Division Director, at the May 17th SqCWD Board Meeting: http://www.scwd2desal.org/documents/Presentations/Status%20Report%20on%20the%20Potential%20for%20Surface%20Water.pdf