FRIDAY, SEPTEMBER 24, 2021
As a result of the worsening drought in Marin County, California, water officials report that they are now considering two options: an emergency pipeline over the Richmond-San Rafael Bridge or a desalination plant.
While the emergency pipeline seems to be the county’s first option, it is now considering the more expensive option of constructing a desalination plant, which would take water directly from the San Rafael Bay.
“So we previously looked at a permanent desalination facility back in 2010,” says Emma Detwiler of the Marin Municipal Water District. “It would be placed down in San Rafael, by the bay, close to the Central Marin Sanitation Agency.”
However, as the county’s reservoir levels continue to drop, officials haven’t given up on the pipeline, as the project would direct larger volumes of water that more closely meet the area’s demands.
“We’re looking at desal as a secondary backup option,” confirmed Detwiler.
Emergency Pipeline Background
At the end of August, officials from the Marin Municipal Water District were gearing up to consider several key approvals to construct what would be a $65 million pipeline across the Richmond-San Rafael Bridge to keep from running out of water as soon as next summer.
According to reports, the six-to-eight-mile-long pipeline would pump in Central Valley water purchased from agricultural areas. The district built a similar pipeline during the drought of 1977.
“As a district, we are very focused on conserving what we have, with the goal of trying to meet this challenge ahead of us through conservation yet recognizing that we may very well need supplemental water,” said Ben Horenstein, the district’s general manager, at the time. “This project is an interesting, yet very complex and costly, endeavor.”
Although the district was planning to have the pipeline completed by June 2022 (without room for delay), the area still suffered a chance of running out of reservoir supplies should it experience another dry winter. The district serves 191,000 residents in central and southern Marin. At the time of reporting, the district’s reservoirs were 36% full.
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| Darin Marchall at Flickr, CC-BY-SA-2.0, via Wikimedia Commons |
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As a result of the worsening drought in Marin County, California, water officials report that they are now considering two options: an emergency pipeline over the Richmond-San Rafael Bridge or a desalination plant. |
At the end of the month, the district was scheduled to consider $2.2 million worth of contracts to study whether the project is feasible and to begin initial design work. According to Horenstien, the feasibility study would be completed in early October.
However, in combing the cost of the study, to build the pipeline and the cost of water purchases, the district estimated that the total cost would land between $60-$90 million.
Earlier this month, one of the district board members was reported to have called for stricter water conservation measures to buy more time and to develop a backup plan should the pipeline fall through.
“I’m concerned that with our best efforts that this project will take more time than what we’re currently predicting and that costs will also be higher,” said board member Monty Schmitt during the board’s meeting on Sept. 7. “As such, I think it’s really incumbent upon us to come up with alternative scenarios right now, which I don’t think we really actually have.”
The board is set to consider a $20 million decision on Oct. 19 on whether to begin prepurchasing construction materials for the pipeline. The lead time is necessary to ensure that the pipe can be manufactured in time to be on the construction site by March, staff said.
“We know that there are supply chain issues—transportation and materials—the things we normally would expect to be delivered without trouble,” Paul Sellier, the district operations director, told the board. “And so it’s important that we maximize the amount of time that we have for procurement of these.”
If the area is to move forward with the emergency pipeline, the board would look to issue a $40 million construction contract in February.
Under the scenario of depleting reservoir supplies by July, construction would need to be completed within four to five months. Sellier adds that the schedule will require about 300 feet of pipe to be constructed per day if the district wants to have the pipeline serviced by the July target.
Desalination Considerations
In developing backup options, the district is now looking at a desalination plant, even though the option would be more expensive and provide less water. In researching their options, the district is reportedly talking with three different companies on its potential options.
If necessary, the district feels confident that it would be able to strike a deal for the project.
“The more successful we are in our conversation, the longer our existing supplies will last, which gives us more time to explore these supplemental water projects,” Detwiler said.
CA Drought Issues
As a result of droughts plaguing the majority of California, last month the Edward Hyatt hydroelectric power plant underwent a forced shutdown as there was no longer enough water available to power it.
According to reports, the plant was taken off-line at the beginning of August after the water level in the Oroville Dam reservoir sank to a historic low of less than 642 feet above mean sea level, or less than a quarter full (24%).
The last recorded low was 643 feet in 1977.
At the time of the announcement, the DWR stated that steps had been taken in anticipation of the loss of power generation, as well as water loss, in its grid management.
More than 95% of the American West is in some level of drought, and seven states—California, Idaho, Montana, Nevada, North Dakota, Oregon and Utah—are entirely in drought. “Exceptional drought” is reported to cover more than 46% of California at this time, attributing to one of the state’s worst droughts and ongoing massive wildfires.
While the Edward Hyatt hydroelectric power plant is just the latest to shut down, back in June, it was reported that the Hoover Dam had undergone a reduction in capacity as southern Nevada’s Lake Mead hit historic lows.
The water from the lake serves a dual purpose for much of the southwest, providing Las Vegas with roughly 90% of its drinking water—while nearly one in every 10 Americans depend on the Colorado River for some of their water and irrigation purposes—and its dam (in normal years) produces 2,074 megawatts, or enough electricity for 8 million people.
Regarding the reduction in capacity, however, the dam is currently producing 1,567 MW, a drop of about 25%. Bureau of Reclamation spokeswoman Patricia Aaron reported that for every foot of lake level decline, energy production loses about 6 MW.
In May, California Gov. Gavin Newsom proposed a $5.1 billion investment, slated to take over four years, for immediate drought response and long-term water investments.
The proposal arrived after Newsom issued a proclamation of a state of emergency on April 21, directing state agencies to take immediate action to bolster drought resilience and prepare for impacts on communities, businesses and ecosystems. At the time, the emergency was announced to exist in Mendocino and Sonoma counties due to severe drought conditions in the Russian River Watershed.
From April to May, the drought emergency extended to 39 other counties, including Klamath River, Sacramento-San Joaquin Delta and Tulare Lake Watershed. Although not in a state of emergency at the time, Newsom also announced that 41 of California’s 58 total counties were in drought.
Of the allotted funding, the plan also includes $1 billion to help residents pay overdue water bills. Other slated investments to support safe drinking water, water supply and reliability and flood resilience include:
For immediate drought support, the plan has slated:
The plan also allots $266 million for water resilience projects to improve ecosystem health for native fish in the Sacramento and San Joaquin rivers and their tributaries; $230 million for ecosystems to improve passage for wildlife or fish; and $200 million for habitat restoration and multi-benefit projects including tidal wetland, floodplain, and flood-risk reduction projects to restore fish and wildlife habitat.
Tagged categories: Bridges; Bridges; Government; Government contracts; Pipelines; potable water; Program/Project Management; Project Management; Upcoming projects; Water/Wastewater
