California American Water Resumes Desalination Test Slant Well Operation

Promising Data Reported; Study Shows 28 Slant Wells Already Operating in the U.S.

After receiving a permit amendment from the California Coastal Commission, California American Water has resumed operation of its test slant well, which was constructed earlier this year to test water quantity and quality at the primary proposed site for the Monterey Peninsula Water Supply Project.

“We’ve picked up where we left off in terms of water quality and production trends,” said California American Water Engineering Manager Ian Crooks. “Our salinity levels continue to increase, indicating a higher concentration of ocean water, which is important to protect the groundwater basin.”

Operation of the test slant well began in April and was stopped in early June, after a relatively small drop in surrounding groundwater levels was observed. The California Coastal Commission permits for the test slant well required Cal-Am to stop operation if such a reduction occurred, then report on its cause and seek a permit amendment before resuming the test. Evaluation of the data revealed that the drop was primarily due to the regional pumping in the area and unrelated to the test slant well operation. The well permits were amended by the California Coastal Commission in early October to clarify that pumping could resume. The test slant well was restarted in late October.

“The act of stopping and starting the well has itself confirmed the integrity of the well’s construction,” commented Crooks. “Physically it was a good test for the well because we got to see how it performed after being restarted, after a period of not operating. The full-scale design includes redundancy and contemplates having some wells off for periods of time. Our recent experience confirms this plan is viable.”

Subsurface intakes, of which slant wells are one type, are considered environmentally preferable to open ocean intakes by many permitting agencies. The California Coastal Commission, State Water Resources Control Board and Monterey Bay National Marine Sanctuary have each stated a preference for subsurface intakes, which draw ocean water through the sand rather than directly from the ocean. National Marine Sanctuary policy requires proponents to determine the feasibility of using subsurface intakes before it will consider open ocean intakes.

California American Water also released a study it commissioned to identify other slant wells used for water supply in the United States. The engineering firm conducting the study found 28 slant wells at 8 locations that were similar in size and design to those planned for the company’s Monterey Peninsula Water Supply Project.

"We are confident in the performance of slant wells, and commissioned this study to learn from the more than two dozen similar wells already in operation in the United States,” said Crooks. “There has been substantial misinformation in the community about slant wells and we are making the findings of this study available to the public to promote a better understanding of technology and others’ experience with it."

A copy of the study and weekly pumping data from California American Water’s test slant well is available at www.watersupplyproject.org.

In 2014, the California State Water Resources Control Board awarded California American Water a $1 million grant for construction of the test slant well.

The Monterey Peninsula Water Supply Project is intended to replace the local community’s current reliance on the Carmel River as its primary source of water supply and is expected to be complete in 2019. More information on the project can be found at www.watersupplyproject.org.

California American Water, a subsidiary of American Water Works Company, Inc. (NYSE: AWK), provides high-quality and reliable water and/or wastewater services to approximately 600,000 people.

Founded in 1886, American Water (NYSE: AWK) is the largest publicly traded U.S. water and wastewater utility company. With headquarters in Voorhees, N.J., the company employs approximately 6,700 dedicated professionals who provide drinking water, wastewater and other related services to an estimated 14 million people in more than 30 states, and parts of Canada. More information can be found by visiting www.amwater.com.

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California American WaterCatherine StedmanOffice: 831-646-3208Mobile: [phone]Email: [e-mail]