Jun 24 2014
Water-The Third Rail Part VIII
Deborah Sullivan Brennan’s puff piece in the 6/23/2014 UT “City Hopes To Tap Into Purification Process” is a public relations effort for the San Diego County Water Authority (SDCWA) and the San Diego Water Department. It was apparently written to show the latter two entities are doing something about reducing our dependence on imported water during this drought. They aren’t….not now, and not for decades.
Careful reading of the article tells us very little will happen for twenty years. By 2035 we might have the facilities in place. How far in the future is that? Five presidential election cycles, ten two year election cycles, and many management people at the SDCWA and the water department will be well into retirement if they are still alive.
When the writer of this blog was a small child asking for something that was unavailable, the common answer was, “We’ll see.” That was how they reduced the number of times the question came up without saying “No”. So it is with the SDCWA and the water department. The date, 2035, is so far away it could be a future date in a sci-fi novel.
The current water purification pilot plant described in the article, if it is ever connected to the city’s system (it is not now connected) will supply one million gallons per day. How much water is that? About one five hundredths of our needs or in percentage, 0.2 percent of our water. Or put another way, it would supply the water needs of less than 500 homes where four people live, i. e., a small tract.
The largest hole in the article a water truck could be driven through, is the lack of any discussion about the price water users will have to pay to fund the water facilities described. Raising the price paid for water may be abhorrent to those seeking to be office-holders, but it is absolutely necessary. It is a major omission to talk about such facilities and not mention how it will be funded. It is analogous to a family planning to buy a luxury car, when their ten-year old Ford finally dies without any concept of how to pay for it.
San Diego Public Utilities Director Halla Razak, when referring to water purification from sewage, is quoted as saying, “It is pretty much cutting edge”. To the great unwashed out here in water-user land, that statement is ludicrous. If that was said in a promo about a “cutting edge” computer containing an 8088 chip [standard in 1980’s PC’s], the laughter would drown out the sales pitch. To her credit, Ms. Brennan talks later in the article about all of the municipalities that have been purifying their sewage to drinking water standards for decades.
And where in the article is any mention of the USEPA waiver expiring next year, July 31, 2015? Could that be important? Could the ominous threat of a Federal fine exposing the city to the financial risk of $25,000 per day be news? A year of such fines [read the current waiver] could go a long way toward funding IPR/DPR.
Come on, UT, get your “Watchdog” on this critical water subject to help San Diegans move toward water independence. No more lengthy articles that say, “We’ll see”.
Milt Burgess
Note: Because of archiving issues with the UT San Diego, the link does not work at the beginning of this article. I am attaching the entire on line article to this post:
CITY HOPES TO TAP INTO PURIFICATION PROCESS
North City facility’s demonstration project fine-tuning how best to purify wastewater
PUBLICATION: U-T San Diego (CA)
SECTION: Main News
EDITION: First Edition
Page: A-1
At the North City Water Reclamation Plant in San Diego, senior engineer Amy Dorman drew a flask of cool, colorlesswater from a tap.
The crystalline liquid had a murky past. It started as sewage, then passed through a series of treatments that scrubbed it as pure as distilled water.
This water, produced at the city’s 1 million-gallon-per-day demonstration project at the North City facility, is the prototype for what may eventually become a major source of San Diego’s water. And it’s a new way of looking at wastewater for the arid West.
“It is very much cutting-edge,” said San Diego Public Utilities director Halla Razak. “There is a lot of excitement, especially with the drought, that this is a sustainable, locally controlled, drought-proof new water supply that is a great solution for the Southwest.”
With that potential in mind, San Diego plans to construct a water-purification plant that would produce 83 million gallons per day by 2035. At that point, purified water could provide about a third of San Diego’s supplies, Razak said.
Officials estimate the project will eventually cost nearly $2 billion. But that expense could be offset by eliminating the need for $1.8 billion in overdue upgrades to the Point Loma Wastewater Treatment Plant, Razak said. And it would help San Diego attain the water self-sufficiency that has long eluded the region.
At the North City plant, a demonstration project that was launched in 2011 has fine-tuned the steps that city officials will follow to produce purified water from wastewater. About 80 percent of wastewater is recycled by the end of the process.
It starts with micro-filtration: rows of plastic tubes containing bundles of tiny straws. Microscopic pores on their surfaces allow water molecules in, then filter out microbes and other contaminants.
From there, the water flows to reverse-osmosis units, which force the water through filters at high pressure to screen out organic material, salts and other solids.
“This is really the workhorse of the whole treatment train,” Dorman said. “This is where 99 percent of what’s in thewater is removed.”
It’s the same process used in desalination, but with less salt to remove, it takes only one-sixth of the energy required to treat seawater, Dorman said.
Water from each canister feeds into separate spigots, and workers test each source individually. So if one of the reverse osmosis units fails, they can quickly isolate the malfunctioning part without shutting down the entire system.
By the time the water runs through reverse osmosis, there are almost no impurities left in it. In the final step, workers run the water through a treatment that employs a combination of ultraviolet light and hydrogen peroxide to obliterate any potential contaminants.
“(The UV treatment) does disinfect 99.9999 percent of virus, protozoa and bacteria, but there isn’t expected to be anything in the water” after reverse osmosis, said water research manager Bill Pearce.
The technology isn’t new: Orange County and Los Angeles already use it, along with water districts in Colorado, Texas, Georgia, New Mexico, Arizona and Virginia, according to the Virginia-based Water Reuse Association.
Most of those districts discharge the treated water into groundwater tables, then draw it up later as needed. But San Diego lacks the large aquifers that many other regions have.
The absence of groundwater is one reason why San Diego has relied so heavily on imported water. And it held the region back from earlier efforts at water purification, said Ken Weinberg, director of water resources for the San Diego County Water Authority.
“In a groundwater basin, the water filters through with soil,” Weinberg said. “The pathogens can’t survive underground, so that acts as a barrier and you get removal of viruses and pathogens.”
Without that convenient storage option, San Diego had to look at other ways to distribute the purified water. Current plans call for piping it to San Vicente Reservoir, where it would be mixed with other supplies of drinking water. A similar system of surface water storage has been in operation at the Occoquan Reservoir in Virginia since 1978, according to the Water Reuse Association.
But there’s a simpler option.
Instead of mixing the water with supplies in the reservoir — a process called indirect potable reuse — the city could ship it straight to treatment plants to blend with other raw-water supplies before additional treatment and distribution. That process, known as direct potable reuse, would require a fourth step in purification — ozone treatment, which the city is studying at the North City facility.
The option of direct potable reuse also would need an OK from state health officials. Razak said she’s working on a state committee that’s exploring the possibility, and will report back on its findings by 2016.
In addition, the city is collaborating with federal regulators on legislation that would exempt it from upgrades to the Point Loma Treatment Plant. The upgrades tab has been pegged at $3.5 billion, with interest.
San Diego is one of the last big cities in the country without secondary treatment — an additional step in filtering wastewater that’s piped to sea. However, officials said removing water from the waste stream through waterpurification would be equivalent to secondary treatment. They’re seeking federal approval for the substitution proposal, Razak said.
In the meantime, the city is starting plans for the first phase of its water-purification system beyond the demonstration project. It’s an addition to the North City Plant that would produce 15 million gallons of purified water per day by 2023. Subsequent facilities planned at South Bay and Harbor Drive would bring that amount up to 83 million gallons per day by 2035.
Other water districts in the county are taking a cue from San Diego. The Helix and Padre Dam districts are exploring a plan to expand the reclamation plant at Santee Lakes to produce purified water, said Helix general manager Carlos Lugo.
The city of Escondido recently approved a long-term capital improvement plan that would create more recycled waterin coming years, and refine that later to produce up to 12 million gallons of potable water to add to Lake Dixon, said utilities director Christopher McKinney.
As all of these initiatives move forward, the county water authority has flagged purified water as the most important new water source for the thirsty region, Weinberg said.
“One of the things that the drought has brought to the forefront is that our traditional way of thinking about waterjust aren’t good enough,” said Melissa Meeker, executive director of the Water Reuse Association. “Historically, we’ve thought of wastewater as a waste product. The reality is that it’s a water resource.”
The Montanan
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