Monterey slant well test back in action

California American Water has resumed operation of its test slant well following a halt in the well’s operation pending a coastal commission ruling.

The stoppage was triggered, under the terms of the project permit by a fall in local groundwater levels. The California Coastal Commission was required to amend the permit before California American could continue with the project.

California American constructed the slant well this year to test water flow and quality at the main proposed site for the Monterey Peninsula Water Supply Project. The project is scheduled for completion in 2019 when it is expected to end the local population’s reliance on the Carmel River as its main water supply.

The slant well operation was stopped in June this year after less than three months’ operation following a drop in surrounding groundwater levels. The commission found that the the groundwater reduction was mainly the result of pumping in the area that was unrelated to the test slant well. The well permits were amended by the California Coastal Commission in early October to clarify that pumping could resume.

“We’ve picked up where we left off in terms of water quality and production trends,” said California American Water engineering manager, Ian Crooks.

“The act of stopping and starting the well has itself confirmed the integrity of the well’s construction,” he added. “The full-scale design includes redundancy and contemplates having some wells off for periods of time. Our recent experience confirms this plan is viable.”

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. Many permitting agencies consider subsurface intakes, like the Monterey slant well as environmentally preferable to open ocean intakes.

California American itself published the findings of a study it commissioned to identify other slant wells used for water supply in the US. The study found 28 slant wells at eight locations that were similar in size and design to those planned for the Monterey Peninsula project.

“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.”