GrokSurf's San Diego

Local observations on water, environment, technology, law & politics

Posts Tagged ‘Direct Potable Reuse’

Helix Water District may close the tap on the El Monte Valley Project

Posted by George J Janczyn on September 4, 2011

This Wednesday September 7 the Helix Water District Board of Directors will consider a staff recommendation to suspend the El Monte Valley Project. The project is a groundwater recharge and recovery operation that would generate 5,000 acre feet of water per year using an advanced recycled water purification process known to water professionals as Indirect Potable Reuse (IPR).

The eastern part of El Monte Valley. El Capitan reservoir and dam are around the bend to the right. The greenery heading down the valley marks the course of the San Diego River. The valley grows considerably wider with distance from the reservoir.

The purification process for potable reuse includes micro-filtration, reverse osmosis, and UV disinfection. San Diego is also developing an IPR project through the Water Purification Demonstration Project at the North City Water Reclamation Plant.

The Helix project has (or had) a lot going for it.

Whereas Helix currently meets 3.3% of its demand for water from local resources, the project would increase that figure to 15%. For all practical purposes, it would create a permanent drought-proof water supply for 15,000 families according to the project’s FAQ — and there would be a corresponding decrease in imported water purchases. Wastewater discharges to the Pacific Ocean would also be reduced.

Another project component would be to mine about 12 million tons of sand from the valley over a 10-year period and sell it to to help fund the project. Much of the sand was deposited by the San Diego River which flows through El Monte Valley west of El Capitan Reservoir. The sand would help ease local shortages of Portland Cement Grade Sand. Upon completion of the mining, the valley would be recontoured and reclamation/restoration plans would be implemented for habitat and recreation purposes.

The staff recommendation to suspend the project (initiated by all four district staff directors and signed off on by General Manager Mark Weston) must have been difficult to decide after the considerable time and resources invested, not the least being preparation of the Environmental Impact Report (EIR) that has been underway for more than a year. Still, to put it simply, the project conditions have changed so much that it no longer seems feasible.

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Posted in Environment, Helix Water District, Indirect potable reuse, Water | Tagged: , | Leave a Comment »

On the proposed overhaul of San Diego’s water policy

Posted by George J Janczyn on March 3, 2011

At yesterday’s Natural Resources and Culture Committee meeting, Councilmember Sherri Lightner unveiled her proposal for an overhaul of San Diego water policy. Click here to see the draft policy.

I addressed the committee during the public comments period. Here’s what I had to share:

Good afternoon. My name is George Janczyn. I publish a San Diego water blog and I would like to share some comments on the overhaul of San Diego’s water policy.

First, although we’ve experienced a fairly wet rainy season, the policy should not succumb to popular pressure to ease water use restrictions. Despite our efforts to develop more local supplies like desalination, Indirect Potable Reuse, and groundwater resources, the fact is that San Diego will always get most of its water by importing it. But our northern California supply is being reduced because of limits on pumping from the Sacramento/San Joaquin Delta; and our current Colorado River allocation is threatened because demand by the lower basin states exceeds what the river can sustain, even if one leaves climate change out of the equation. Eventually there could be reductions in water from the Colorado River as well.

As demand for water grows in San Diego, providing a reliable supply will become more challenging.

San Diegans need to develop a mindset for living in an arid region and discard the notion that strict conservation is needed only periodically when there’s a severe drought. San Diego needs a policy of more rigorous conservation practices…and permanently, not just when there’s a dry year.

Second, the policy should be more assertive in supporting potable reuse for high-quality and reliable local water. Despite the fact that the previous city councils strongly promoted a potable reuse policy, some committee votes more recently have actually hindered development on that front and the new proposed water policy only half-heartedly offers this:

“Support indirect potable reuse if the Water Purification Demonstration Project is successful.”

We need to look forward on the use of IPR.

The original plan was to have full-scale IPR reservoir augmentation that will produce only 16 million gallons per day. What the committee should do now is look into the feasibility of increasing that amount to a meaningful number, say 50 million gallons per day using Direct Potable Reuse, so that it would be on a par with the output of the upcoming Poseidon desalination plant.

Planning for an eventual 50 million gallons per day for San Vicente reservoir augmentation would require study. In order to accommodate that much capacity, the use of San Vicente Reservoir as a six-month environmental buffer might not be possible. While the reservoir could still be used for storage of the purified reclaimed water, the higher volume of water would mean more turnover in the reservoir so the time period would have to be shorter – in essence the indirect potable reuse aspect would cross over into being Direct Potable Reuse (DPR) which would raise new questions about safeguards.

On that topic, note that California Senate Bill 918 (Pavley) would require the State Department of Public Health, in consultation with the State Water Resources Control Board, to investigate the feasibility of developing water recycling criteria for DPR. More immediately, I’ve learned the WateReuse Research Foundation might soon support a study on DPR feasibility. The NR&C committee should consider asking the Public Utilities Department to support or coordinate with the Foundation on such research.

In any case, San Diego water policy should more firmly promote Potable Reuse as an integral component of our water strategy.

Thank you.

See also:

Posted in Indirect potable reuse, Natural Resources and Culture Committee, Water, Water conservation | Tagged: , | 4 Comments »