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Archive for the ‘Indirect potable reuse’ Category

Purified recycled water…it’s perfectly clear

Posted by George J Janczyn on May 29, 2012

Here’s a nicely done educational/promotional video (just over 5 minutes) from the San Diego County Water Authority with the collaboration of the Escondido Water District, Helix Water District, Padre Dam Municipal Water District, and the City of San Diego.

These agencies are working hard to take advantage of purified recycled water to reduce our dependence on imported water, create the potential to improve the quality of the raw supplies now imported, reduce the amount of wastewater discarded into the ocean, and ultimately reduce the cost of water relative to imported water.

(if you’re a GrokSurf email subscriber, the video may not run in your mail program. In that case, just click on the title of the post to go to the web version)


Posted in Environment, Indirect potable reuse, Purified recycled water, Videos, Water | 6 Comments »

San Diego’s indirect potable reuse proposal without the hype

Posted by George J Janczyn on February 27, 2012

The City of San Diego is studying the feasibility of using purified recycled water to bolster its reservoir supply through its Water Purification Demonstration Project (originally called the Indirect Potable Reuse Reservoir Augmentation Demonstration Project).

Potable reuse has been a controversial and emotional topic in San Diego’s quest for new water resources. Provocative stands by certain politicians and pejorative headlines in some news media obscure a key underlying fact: for San Diego the real issue is unplanned vs. planned indirect potable reuse.

San Diego imports about 80% of its water from Northern California and the Colorado River. Imported water from these sources contains treated wastewater from over 345 municipal wastewater facilities [citation] — and when we get it, it only gets standard water treatment before delivery to customers. This is called unplanned indirect potable reuse. We’ve been doing it all along.

By contrast, under San Diego’s planned indirect potable reuse proposal, recycled water (aka treated wastewater) would subsequently go through a multi-staged advanced purification process rendering it similar in quality to distilled water. The purified water would be blended with our imported raw water in the San Vicente Reservoir. So, in fact we would actually improve the overall quality of the imported water before it goes to the final water treatment plant.

The goal, if the demonstration project is successful, is to produce 16 million gallons per day via the potable reuse process. That’s 16 million gallons per day less in imported water purchases, and 16 million gallons per day less in wastewater discharge into the ocean.

The Demonstration Project is also performing a limnology study to determine the reservoir mixing and dilution dynamics associated with adding the purified recycled water.

Over the last year the City of San Diego has been conducting educational presentations and guided tours of the advanced purification facility. The Water Reliability Coalition, a broad-based coalition of community organizations and groups has formed to further educate the public about potable reuse in San Diego. Polls indicate growing public acceptance of the process.


Reprinted from a page in the Topical Guide section of this blog. That page includes the latest news reports on the subject and a selected bibliography on potable reuse and related topics.


Posted in Environment, Indirect potable reuse, Water, Water Purification Demonstration Project | 8 Comments »

San Diego Water Reliability Coalition launches website

Posted by George J Janczyn on September 14, 2011

The Water Reliability Coalition (or WRC), an association of San Diego County environmental, technical, business, and ratepayer organizations formed to perform public outreach in support of Indirect Potable Reuse (IPR) research and development announced yesterday the launch of its new website at

When WRC came together in late 2009 as the Indirect Potable Reuse (IPR) Coalition, the City of San Diego was embarking on its Indirect Potable Reuse Reservoir Augmentation Demonstration Project (IPR/RA Demonstration Project). Lani Lutar (San Diego County Taxpayers Association) and Bruce Reznik (at the time at San Diego Coastkeeper) were instrumental in organizing the coalition. Lutar is still at it, and Gabe Solmer is the new leader from Coastkeeper.

In March 2010 the Coalition received a special recognition award from the California WateReuse Association for its efforts.

The Coalition believes that potable reuse shows great potential as a component of San Diego’s water supply strategy because it represents a steady reliable source of high-quality potable water and has the environmental benefit of reducing the amount of wastewater dumped into the Pacific, among other reasons.

In early 2010 San Diego began to publicize its IPR project as the Water Purification Demonstration Project partly to simplify saying the name and partly to get some distance from lingering impressions caused by negative politics and press during IPR initiatives in 2007 and earlier (the original name is still used for internal documentation and official Council business).

Consequently, the IPR Coalition changed its name to the Water Reliability Coalition in September 2010, partly in response to the City’s project name change and partly because the name echoes sentiment behind a long-time San Diego goal to improve supply reliability by reducing its 80% dependence on water imports. The Coalition then decided to build a website, not an easy task with numerous coalition members with other priorities and economic challenges to deal with. It took a bit longer than they hoped, but it’s here now. It’s good to see it up.

(see also this writeup about the Coalition from Bradley Fikes at the North County Times)


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

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.

Read the rest of this entry »

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Advanced water purification facility begins operations for San Diego’s indirect potable reuse study (IPR)

Posted by George J Janczyn on July 1, 2011

The City of San Diego’s IPR study, now officially referred to as the Water Purification Demonstration Project by the Public Utilities Department, just passed a major milestone: the Advanced Water Purification Facility needed for the project is completed and operations have begun.

It’s been nearly one year (July 27, 2010) since the City Council approved a contract with Camp Dresser McKee for the advanced water treatment facility. The facility is a key component of the Demonstration Project which will study whether it’s feasible to purify recycled water to potable standards. The $11.8 million cost of the project is being funded with money generated from a temporary water rate increase for the past few years. The rate increase was cancelled after the needed funds were obtained.

The advanced purification facility was built to blend in as part of the North City Water Reclamation Plant. The reclamation plant currently cleans and processes wastewater to the tertiary level* which is clean enough to be used for irrigation and some industrial purposes (*this Wikipedia article provides a good overview of different levels of treatment).

Under the Demonstration Project, which is planned to take one year, a portion of tertiary-treated recycled water from the reclamation plant is diverted to the advanced purification facility where it is further processed through ultra- and micro-membrane filtration, reverse osmosis, and ultraviolet light with hydrogen peroxide for advanced oxidation and disinfection.

The advanced purified water will be continuously analyzed in laboratories. The remainder will be blended with the tertiary recycled water and delivered to recycled water customers. That’s almost like adding drinking water to the recycled stream, which means it’s likely customers will get better quality recycled water than before (for the duration of the demonstration project in any case).

Yesterday (Thursday) there was a celebratory “kick off” for the project at the North City Plant. Mayor Jerry Sanders, Councilmember David Alvarez, Public Utilities Department Director Roger Bailey, and Public Utilities Department Deputy Director Marsi Steirer spoke to mark the occasion. Afterwards we had a brief tour of the facility.

Local news media reporters were out in force covering the event. You’ll find varying points of view about the concept — and as usual there are a few folksy or provocative pieces along with potty headlines.

Here’s a collection of reports on Thursday’s event so far:


By the way, public tours of the Advanced Water Purification Facility are available. Register at

Here are some photos (click for enlargements):


















Posted in Indirect potable reuse, Water, Water Purification Demonstration Project | 3 Comments »

Helix Water District holds public scoping meeting for groundwater recharge IPR project in El Monte Valley

Posted by George J Janczyn on March 9, 2011

El Monte Valley. El Capitan Dam is around the bend a couple of miles.

The Helix Water District held a public meeting yesterday to give notice that it is beginning preparation of an Environmental Impact Report (EIR) for the proposed El Monte Valley Project (or more completely, the El Monte Valley Mining, Reclamation, and Groundwater Recharge Project).

El Monte Valley lies just west of El Capitan Reservoir and dam, with the San Diego River channel running through its length. Beneath the valley is a groundwater aquifer that provides water to the Helix district and many valley residents with wells on their property. The project aims to recharge the aquifer with purified recycled water (aka indirect potable reuse, or IPR) that would be piped in from a facility in Santee and emptied into recharge basins to percolate into the ground. Some injection wells might also be used for the recharge process, which would raise the water table for the slowly depleting aquifer and provide the district with an additional 5 million gallons of water per day.

Other components of the project are a temporary (8-10 years) sand-mining operation that would help pay the cost of the project. Parts of the valley and river channel would then be graded, contoured, and restored for riparian habitat with native plants and trees and recreational features including hiking and equestrian trails.

Yesterday’s “Scoping Meeting” was held as an adjourned board meeting at the district’s La Mesa offices at 7811 University Avenue at 7pm. The primary reason for the meeting was to get feedback from stakeholders and interested persons about topics of concern they would like to have addressed by the EIR.

About 75 people attended this meeting. After a brief overview of the project by Tim Smith, Project Manager, about 14 people spoke on a variety of viewpoints.

Read the rest of this entry »

Posted in Environment, Helix Water District, Indirect potable reuse, Land use, 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 »

Water news from the Natural Resources & Culture Committee

Posted by George J Janczyn on February 1, 2011

The San Diego Public Utilities Department submitted the following reports for the Feb 2 meeting of the City Council Natural Resources & Culture Committee.


Posted in Indirect potable reuse, Water, Water conservation, Water Purification Demonstration Project | Tagged: | Leave a Comment »

Helix Water District holds stakeholders meeting for El Monte Valley Project

Posted by George J Janczyn on October 13, 2010

Yesterday, the Helix Water District held the second in its series of stakeholder meetings for the El Monte Valley Project at 6:30pm at the Lakeside Christian Church on El Monte Road. The project seeks to recharge the District’s aquifer beneath the valley using treated wastewater purified with the Indirect Potable Reuse (IPR) process–the same process that will be used in San Diego’s Water Purification Demonstration Project. The project will produce enough water to serve approximately 15% of the District’s total water demand.

The District introduced the project plan to valley residents and stakeholders last July 21 and promised to consult with them regularly. In addition, presentations have been made to a variety of groups throughout the county.

In addition to groundwater recharge with IPR water, the Helix plan envisions extensive riverbed restoration with native plants, public recreational space for hiking and equestrian use, and wildlife habitat. A portion of the valley previously zoned for mining will be tapped for sand and gravel which will be sold to help defray project expenses and to help re-contour the riverbed for the restoration.

Yesterday’s stakeholders meeting was to get feedback on the recreational space envisioned for the valley, in particular on design parameters for multi-use trails.

Principal Engineer Tim Smith discussing trail design

Attendees were seated at round tables with 3-7 persons per table. A large map of of the valley showing project components was provided for each table. Everybody was given a copy of initial trail design parameters based on the San Diego County Community Trails Master Plan specifications for rural trails, and they were asked to spend about 25 minutes discussing them and listing issues and concerns. Afterwards, a “captain” selected at each table gave a report on the table’s discussions.

The trail design handout called for multi-use trails on the north and south side of the valley, 6-10 ft. wide, with 2-5 river channel crossings. Trail material would be native soil. The trail would be fenced on the river side, with a slope less than 15%, and would be kept well away from project facilities.

Residents study map with District General Manager Mark Weston (second from the right).

Some issues came up repeatedly: potential conflict between equestrian and biking was a concern; many felt the trail should be wider so that two horses could pass in opposite directions comfortably; restroom facilities, staging areas, and security patrols were other common themes.

One person noted that many equestrian users come to the valley from other locations and they should be considered stakeholders as well. Another worried that planting near the river with riparian vegetation would create spots that could attract transients. Several people wondered who will maintain the trails?

A number of people began raising issues related to the project as a whole. A few people wanted the project to just go away and leave the valley alone. Concern about dust, noise, and traffic during construction was expressed. Someone worried that their property value would decrease because of the project. Many are unhappy that they will no longer be able to use their existing wells for drinking water (due to state regulations) and feel that it’s unfair they will have to purchase water from the District.

The valley is under attack from two sides and we can’t do anything about it, another person complained, saying that the Helix water project reconfigures the valley and riverbed on one hand, and on the other hand the Sunrise Powerlink electrical transmission lines planned for the valley will bring fire danger and visual blight.

In closing remarks, General Manager Mark Weston encouraged people to visit the District website for more details. He also announced that a November field trip is being planned to visit the Orange County advanced water treatment facility that will be the model for the plant to be used for this project. The trip may need to be deferred until early next year, though, unless enough people sign up for the tour.

For more information about the project, here’s the El Monte Valley Project website.

Also here’s my report describing the project and stakeholders meeting in July.


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

Should San Diego ozonate its wastewater for IPR?

Posted by George J Janczyn on October 5, 2010

San Vicente Reservoir, August 2010. Water level has been lowered to allow dam raise construction.

As San Diego prepares to embark on its one-year Water Purification Demonstration Project with the eventual goal of augmenting San Vicente Reservoir with purified wastewater (planned indirect potable reuse, or IPR), the biggest public concern about actually implementing that process — besides the considerable expense — will probably be water quality. The sheer persistence of the terms ‘recycled sewage’ and ‘toilet-to-tap’ in the news media is an indicator of that lingering concern.

To be sure, there’s reasonable certainty that the advanced treatment process is very reliable. Scientific studies have shown that the advanced steps of micro/ultra filtration, reverse osmosis, and UV/peroxide are effective for removal of pharmaceuticals and endocrine disrupting compounds (EDCs) from wastewater. Indeed, the City of San Diego previously completed a small-scale 18-month pilot testing program to determine the effectiveness of the advanced water treatment process being used in the new demonstration program, with the conclusion that the product water met all federal and state drinking water standards. However, the test is being repeated in this one-year project because the California Department of Public Health wants a test that would use the same size equipment and monitoring devices that we would use for a full scale project, according to Alma Rife, Public Information Officer for the San Diego Public Utilities Department.

Still, although pharmaceuticals and EDCs are held below state and federal threshholds (and are sometimes undetectable) after treatment, it is known that trace amounts can remain and there’s no consensus about their cumulative effect on humans. Further, the effect of EDCs on aquatic ecosystems (e.g., feminized male fish) has certainly been documented.

There’s growing awareness in many communities, being downstream from other communities, that treated wastewater already exists in their source water supply. That’s called unplanned indirect potable reuse and it’s certainly happening in San Diego via its imported water from the Colorado River and Northern California. Consider the following:

“…pharmaceuticals and EDCs have been detected in many water bodies around the world […] and are now considered ubiquitous wastewater contaminants. Undoubtedly, the major contributor of such widespread contamination is municipal wastewater discharge. Indirect potable water reuse, either planned or unplanned, occurs when wastewater treatment plant discharge comprises a portion of the receiving stream’s total flow. In many cases, surface water with some degree of wastewater influence is used as source waters for drinking water treatment facilities leading to the presence of these compounds in source and finished drinking water. Thus, the propensity for surface water or drinking water contamination will grow with human population growth and generation of additional wastewater.”

[S.A. Snyder and M.J. Benotti. Endocrine disruptors and pharmaceuticals: implications for water sustainability. Water Sci Technol. 2010;61(1):145-54]

The bottom line is that regardless of the source of our drinking water, whether Northern California or the Colorado River, we’re presently doing unplanned IPR. So now that we’re now looking at doing planned IPR through reservoir augmentation, is enough being done to address the trace contaminants that have been quietly tolerated in the past?

The treatment regime now contemplated for San Diego’s IPR project is: activated sludge, secondary clarification, tertiary precipitation, micro filtration, reverse osmosis, and UV/peroxide. The treatment plan is modeled on Orange County’s program because that program has already been permitted by the California Department of Public Health, according to Ms. Rife.

What about ozonation?

Ozonation is more effective than chlorine as a disinfectant and it can eliminate contaminants that even UV treatment can’t remove.

One doesn’t hear much about ozonation being used to treat wastewater. It’s more commonly used for drinking water treatment plants. In fact, a new ozonation facility near completion at San Diego’s Alvarado Water Treatment Plant is expected to go online by December (that plant treats water from San Vicente).

But when I visited the Southern Nevada Water Authority and Las Vegas Valley Water District water facilities to get a closer look at their operations, I learned that they just completed a pilot ozonation project at the Clark County Water Reclamation District, where much of their wastewater is treated (you may be aware that Lake Mead is their drinking water source as well as the destination for their treated wastewater).

Since Las Vegas already uses ozonation for their drinking water treatment plants, why also for wastewater?

Doug Drury, Asst General Manager for Water Quality, Research & Technical Services at Clark County Water Reclamation Plant (CCWRP), told me that some of the thinking that went into the decision to add ozonation to the other advanced treatment procedures included:

  • Substantial scientific documentation confirms the effectiveness of ozonation towards elimination of EDCs and PPCPs (pharmaceuticals and personal care products)
  • In testing, 60 samples for enteric virus were negative after ozonation, but not after UV treatment alone
  • Cryptosporidium was found in the Las Vegas Valley in recent summers
  • Lake Mead is less than half-full now but treated wastewater inflows remain the same, so there is less dilution and an apparent increase in concentration of contaminants in the reservoir
  • Potential environmental impact on aquatic ecosystems
  • Downstream water user concerns

HPLC unit at the Southern Nevada Water Authority Water Quality Laboratory

Not only did CCWRP perform that pilot study, but they approved $50 million for a permanent ozonation system. That’s a good sum of money; obviously they’re convinced that ozonation is doing something good. Interestingly, it appears they will also phase out reverse osmosis because of the 10-15% water loss involved in disposing of the resulting brine.

Ozonation is cited in another study as being the “most responsible for the removal of pharmaceuticals and EDCs” and “though many ozone plants also utilize chlorine, ozone is a stronger oxidant.”

In San Diego we’re looking to augment a reservoir that’s a lot smaller than Lake Mead. The San Vicente Reservoir will eventually have a capacity of around 250,000 acre-feet after the dam raise is complete. There’s only so much dilution that can occur when you add 16 million gallons per day of treated wastewater to a reservoir that size. So while public perception may find it acceptable to dilute wastewater in a large body of water such as Mead within the flow of the Colorado River, it could well be that the public will balk at the same thing being done at San Vicente Reservoir — and remember, public perception killed San Diego’s IPR project last time it was attempted.

Adding ozone to the IPR treatment regime could ease the public mind, but it’s probably a far-fetched idea for us. Ozonation on the wastewater side might convince some people who are still undecided about indirect potable reuse but it would be an extreme expense for what would really be a marginal benefit — and we’re already being squeezed with rising prices for water. Besides, we haven’t even managed to treat the bulk of our wastewater stream to secondary standards yet.

Ultimately, education will be key to a successful IPR project. The city’s public outreach and education program for the Demonstration Project has gotten underway with meetings with neighborhood planning groups, but those are just introductory project overviews. The challenge will be to go beyond the generalities (such as provided in the monthly IPR updates to the NR&C city council committee) and share complete, up-to-date, highly detailed water quality and cost information about IPR regularly and persistently. Tours of the new advanced treatment facility have been promised; the same should be done with the water quality lab. A blog-like news section on the city’s project website could help to stream out the details.

Many San Diegans have been squeamish about IPR despite it being a proven and safe technology. Providing access to plenty of information will be vital for overcoming that problem. On that note, this report from the independent Equinox Center is deserving of wide circulation (reprinted with permission).


Posted in Environment, Indirect potable reuse, Water, Water Purification Demonstration Project | 5 Comments »