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Posts Tagged ‘Recycled water’

San Diego faces a major decision on wastewater treatment and water recycling [update]

Posted by George J Janczyn on July 16, 2013

The story below was originally published April 24 but it seems timely to revive it in order to highlight a new report presented at San Diego’s Independent Rates Oversight Committee (IROC) yesterday (Monday July 15). The two handouts distributed at the meeting contain most of the information discussed and are provided here.

Preferably you’ll read the story first (if you missed it) and then the IROC meeting handouts. Otherwise just click the two images below to read the handouts:

 

JPAStrategy JPANarrative

 

______________________________

 

For more than a year San Diegans have been recipients of news media reports and a public outreach program explaining the city’s one-year Water Purification Demonstration Project (WPDP). Yesterday (Tuesday April 24), the City Council got the final report and discussed possible next steps. Local news media have yet to weigh in on this story, so here’s a start:

The goal of the WPDP was to determine the feasibility of taking recycled water and purifying it in a special advanced treatment facility located at the North City Water Reclamation Plant, sending the purified water through a pipeline to the San Vicente Reservoir where it would blend with imported water from the Colorado River and Northern California, and then be piped to the city’s Alvarado Water Treatment Plant for final purification and distribution to residents (in emergencies the water could go to other treatment plants but Alvarado would be the default). The process is sometimes referred to as Indirect Potable Reuse through Reservoir Augmentation, or IPR.

Click image to enlarge. Recycled water is produced by treating wastewater to a "tertiary" level after which it is used for irrigation and commercial/industrial applications.  The IPR process takes some of the recycled "tertiary" water and puts it through an advanced purification process that renders it similar in quality to distilled water.

Recycled water is produced by treating wastewater to a “tertiary” level after which it is used for irrigation and commercial/industrial applications. The IPR process takes some of the recycled “tertiary” water and puts it through an advanced purification process that renders it similar in quality to distilled water.

 

The report “provides an overview of the technical studies, advanced water purification facility testing, and public education and outreach efforts conducted as part of the Water Purification Demonstration Project. It also presents findings that support the conclusion that a reservoir augmentation project at San Vicente Reservoir would be feasible.”

In short, IPR was shown to be technically sound and, if a recommended large-scale project is approved, would provide the city with about 15,000 acre-feet per year of safe, sustainable, reliable, locally sourced potable water.

A large-scale IPR program would also significantly reduce the amount of wastewater discharged into the ocean. And if a full-scale program works out well, the program could eventually be expanded to build additional satellite advanced purification facilities and recycle 90,000 acre-feet or more per year. That’s 90,000 acre feet less water lost to wastewater discharge.

The City Council enthusiastically accepted the report. Now it needs to decide whether to authorize a full-scale IPR program. That decision will have to wait until Public Utilities Department staff report back in 90 days to the Natural Resources & Culture Committee with a recommended preferred plan. The committee would then forward a recommendation to the full City Council.

The really big part of this story, though, is that San Diego’s wastewater management policy has been a problem for many years and it’s in that context that the potable reuse program needs to be understood.

The Point Loma Wastewater Treatment Plant

Point Loma outfall pipeline where it enters the Pacific.

Point Loma outfall pipeline where it enters the Pacific.

Google Maps view shows the underwater 4.5 mile outfall pipeline and diffuser

The underwater 4.5 mile outfall pipeline and the “Y” diffuser can be seen on this Google Maps image

Because of its arid climate and limited local resources, San Diego needs to import some 80% of its water from hundreds of miles upstream, mainly the Colorado River and northern California. Before San Diego gets its water, upstream municipalities consume some of that water, much of which turns into wastewater. They treat their wastewater and discharge it into the flow of water that continues to downstream communities, where the process is repeated. And repeated.

By the time imported water gets to San Diego, the imported water contains the discharge from some 300 upstream wastewater treatment plants. That should be thought-provoking enough, since San Diego’s water only gets treated in a standard water treatment plant, not an advanced purification facility as is being proposed.

Since there are no users downstream of San Diego, the city discharges its wastewater into the Pacific Ocean from the Point Loma Wastewater Treatment Plant, to the tune of roughly 175 million gallons each day. There’s a problem with that, and not just because so much water gets wasted by dumping it.

The federal Clean Water Act requires wastewater discharges to receive “secondary treatment,” and that’s what the upstream communities do. San Diego, however, does not. Instead it does what it calls “advanced primary” treatment.

Back in 1988, the EPA sued the city for failure to achieve secondary treatment. The city, however, felt that an upgrade to secondary would be unnecessarily and exceedingly expensive (likely more than $1.5 billion that ratepayers would have to fund) and that the parcel of land on which the Point Loma plant lies is so small that it was impossible to expand it.

Ultimately, the EPA agreed to give San Diego some leeway, but as mitigation the city had to develop a water recycling/reclamation program with a capacity of 45 million gallons per day (mgd) and monitor the “advanced primary” Point Loma effluent plume dispersed into the Pacific to ensure discharge quality would fall within specified limits.

The reduction in wastewater discharged from Point Loma along with ocean monitoring would be good for the environment, while recycling would provide more usable water for the city.

Thus was born the 30 mgd capacity North City Water Reclamation Plant (1997) and the 15 mgd capacity South Bay Water Reclamation Plant (2002), along with a “purple pipe” network to distribute recycled water treated at the “tertiary” level to large customers for irrigation and certain commercial/industrial uses.

But things didn’t work out as well as expected.

As reported by a Water Online news report:

In 1997, the San Diego Water Department raided its cash reserves of $65 million intended for fixing the city’s crumbling drinking water system. It used that money to lay 46 miles of purple pipeline to customers in Mira Mesa, Torrey Pines, Scripps Ranch and University City.

Recycled water has turned out to be a big bust. It cannot be sent through existing water lines, it requires expensive construction of new pipelines (“purple pipe”) to distribute the water to customers. Then the customers have to retrofit their existing plumbing or irrigation system with parallel purple pipe systems. The city spent over $18 million to assist customers with that expense. A retrofit of Miramar Nurseries, for instance, cost the city $300,000, according to Hossein Juybari, the city’s recycled water coordinator. The golf course at Miramar Marine Corps Air Station is being replumbed at a cost of $700,000 to the city. The EPA figured the city could reuse 25 percent of the flows of the North City plant by the end of 2003, a goal it set when it granted the city $70 million toward construction. Currently, the city is reusing less than 17 percent of the sewage processed at North City, and water officials say they have no hope of reaching 25 percent anytime soon. By 2010, the EPA goal for the city becomes 50 percent.

[The City has not responded to my request for comment on the veracity of this report]

Another setback to recycling occurred with this 1999 City Resolution ordering the City Manager not to spend money on “water repurification.”

Meanwhile, the City received another EPA waiver for Point Loma in 2001 and lawsuits were filed by San Diego Coastkeeper, the San Diego chapter of the Surfrider Foundation, and the San Diego chapter of the Sierra Club. That history is documented in a memo written by Marco Gonzalez from the Coast Law Group.

According to Gonzalez, there were 3 points to address:

  • Issuance of the waiver in the proposed form violated federal CWA [Clean Water Act] anti-degradation and anti-backsliding regulations.
  • Failure by the City to achieve 45 million gallons per day (MGD) of sewage reclamation was a violation of OPRA [Ocean Pollution Reduction Act], and that merely constructing reclamation capacity without implementing beneficial reuse was insufficient.
  • The plume outfall [from Point Loma] monitoring program was not sufficient to accurately characterize plume migration and impacts.

(Gonzalez’s memo goes into considerable detail about the negotiations and events during that period. It is a fascinating read, posted here with his permission.)

The outcome of these negotiations brought about the following:

1. Acknowledging that the Point Loma wastewater plant lacked sufficient space for expansion, the groups proposed, and the city agreed, to conduct a pilot study of one of the more promising technologies – called Biologically Aerated Filtration (BAF) – to see if it could achieve secondary standards given the quality of Point Loma’s sewage influent and flow demands.

2. A monitoring program by an independent team of technical experts from the Scripps Institution of Oceanography would be assembled to determine the effectiveness of Point Loma’s “advanced primary” treatment.

3. The City would further consider advanced treatment of its reclaimed water for comingling with imported water supplies in drinking water reservoirs [i.e., indirect potable reuse].

Point #3 above resulted in the 2005 Water Reuse Study intended to look at how we might maximize the use of reclamation capacity then existing at North City and South Bay. Following this study, the decision was made to pursue the IPR Demonstration Project. During this same period, a coalition of environmental, business, labor, and trade groups formed the “IPR Coalition” to advance the cause.

______________________________

Years passed as these issues were hashed out. A stronger ocean monitoring program was developed, but the capacity of the two reclamation plants remains underutilized.

At the end of 2008, the City Council overrode a mayoral veto and authorized the raising of funds to pay for the IPR demonstration project (which later got the name Water Purification Demonstration Project).

In 2009, the city needed to apply for a new 5-year EPA waiver, the environmental groups opposed it and promised lawsuits, but Marco Gonzalez and Bruce Reznik offered the City a “non-opposition” to the waiver (very different from “support”) in exchange for the much more in-depth water reuse study considering the possibility of maximizing reclamation and minimizing discharge to the ocean.

With this agreement in place, the city was able to get another waiver. But the EPA and California Coastal Commission warned the city that future waiver requests would not be looked upon favorably.

However, as Mr. Gonzalez wrote in his memo, “the light bulb went off:”

“The goal of the Clean Water Act is not simply to ensure compliance with water quality standards and to achieve the cleanest runoff mandated by federal or state laws. Rather, the structure and purpose of the CWA is geared toward minimizing and when possible eliminating discharges altogether [emphasis added]. Given the value of water in San Diego (at the end of the Colorado River and State Water Project pipelines), the likelihood of continued drought, the technological gains in reverse osmosis, the relatively dirty source water entering our reservoirs, the political and public acceptance for desalination, and a host of other political, economic, and social factors, there is no way San Diego can sustain its current paradigm of pushing sewage down to Point Loma and off into the Pacific Ocean…. Looking at the current paradigm of water supply and sewage conveyance/treatment, the ONLY sustainable option is IPR. With this perspective, our goal became clear. We want to eliminate all discharges to the ocean and maximize IPR as soon as economically, technically, and politically feasible.”

The IPR Coalition, now named the Water Reliability Coalition, continues its work to this day (for some reason the website appears to have been hijacked but they’ve been notified).

Next steps

The clock is ticking for the Point Loma plant. Under the current waiver, the city is already on notice that future waiver requests will not be looked on favorably. Last October, the California Coastal Commission sent a letter to the City expressing “significant concern that the City has not yet committed to milestones and implementation schedules that would enable the City to end the pursuit of future secondary treatment waivers.”

If the city doesn’t demonstrate substantial progress, a new Point Loma waiver might not be easily won and the city could face fines, penalties, and lawsuits as a consequence. The waiver expires July 31, 2015; a renewal application will have to be made in 2014. I’ve learned the Public Utilities Department Director Roger Bailey is now leading a Point Loma waiver strategy team but haven’t been able to obtain more information about it.

San Vicente reservoir before the dam raise project

San Vicente reservoir before the dam raise project

The heightened San Vicente Dam increases the reservoir capacity from 90,000 acre-feet to 242,000 acre-feet.

The heightened San Vicente Dam increases the reservoir capacity from 90,000 acre-feet to 242,000 acre-feet.

The City Council’s acceptance of the IPR project report is certainly progress. But in accepting the report, several City Council members indicated a desire to also explore Direct Potable Reuse, or DPR as a less expensive alternative to IPR. Whereas the IPR proposal involves construction of an expensive pipeline to the San Vicente Reservoir (which, incidentally, has been vastly expanded), DPR would send the water directly to the potable water treatment plant (likely Alvarado), using a much shorter pipeline, with no detention time in a reservoir. That could save more than $200 million in pipeline construction, but also raises questions about safety and regulatory approval.

So much time, effort, and expense has gone into clearing regulatory hurdles for the IPR project, that DPR, for all its attractiveness, could be a distraction from work that is still needed for IPR. The California Department of Public Health (CDPH) and the San Diego Water Board have indicated general acceptance of San Diego’s IPR project, but it is many years away from regulatory approval for DPR. Senate Bill 918 requires CDPH to investigate the feasibility of developing uniform water recycling criteria for direct potable reuse and to provide a final report on that investigation to the legislature by December 31, 2016. The regulations will come some years after that.

One option could be to proceed with a large scale IPR program with a pipeline to San Vicente as already envisioned. Subsequently, satellite advanced treatment plants could be built for DPR. That would allow San Diego’s waiver application to say we’re making substantial progress. It would also allow time for CDPH to issue regulations for DPR…it seems likely that won’t happen for many years beyond 2016.

Assuming the preferred path is IPR now and DPR in the future, the issue is still how to get things moving? What questions need to be addressed?

At the City Council meeting, PUD’s Marsi Steirer said the cost of IPR would not only be lower than the cost of desalination, it would be cheaper than imported water (around $1,000 per acre foot). That’s competitive with the price of imported water, but according to the Project report the actual cost is about $2,000 per acre foot—around where desalination is priced. Reading from the report:

“If full-scale reservoir augmentation is implemented, the city would not need to build a 7 million gallon wet weather storage facility to attentuate wastewater flow to Point Loma; reduced overall flow to Point Loma would reduce annual operations and maintenance costs at Point Loma plant and Pump Station 2 which conveys flows to Point Loma. Water salinity in the city water supply would be lower, potentially reducing costs further. Taking these factors into account PUD estimates the NET cost for IPR would be about $1,000 per acre foot.”

But wastewater has to be treated at Point Loma or at the North City reclamation plant, so are the savings really that great or is the cost just being shifted from Point Loma processing to North City processing? It will be interesting to see if the sewage treatment portion of our water bill shows a price decrease. So, next steps would appear to be:

  • IPR would benefit both water and wastewater systems, therefore proportional share of costs needs to be determined in order to prepare water and wastewater rate cases
  • Determine a contracting mode
  • Refine pipeline alignment, which represents an estimated 60% of total implementation cost
  • Coordinate with regional wastewater and reuse objectives including Point Loma waiver expiration in 2015
  • Monitor development of DPR regulations

In any event, it doesn’t seem wise to argue that we should embark on IPR because it is cheaper. It may or may not be less expensive than desalination or imported water in the long run, but IPR is clearly the right thing to do.

______________________________

I welcome any comments that can correct and improve on this report.

Some sources for this story that may be of interest:

 

Posted in Water, Water Purification Demonstration Project | Tagged: , | Leave a Comment »

San Diego faces a major decision on wastewater treatment and water

Posted by George J Janczyn on April 24, 2013

For more than a year San Diegans have been recipients of news media reports and a public outreach program explaining the city’s one-year Water Purification Demonstration Project (WPDP). Yesterday (Tuesday April 24), the City Council got the final report and discussed possible next steps. Local news media have yet to weigh in on this story, so here’s a start:

The goal of the WPDP was to determine the feasibility of taking recycled water and purifying it in a special advanced treatment facility located at the North City Water Reclamation Plant, sending the purified water through a pipeline to the San Vicente Reservoir where it would blend with imported water from the Colorado River and Northern California, and then be piped to the city’s Alvarado Water Treatment Plant for final purification and distribution to residents (in emergencies the water could go to other treatment plants but Alvarado would be the default). The process is sometimes referred to as Indirect Potable Reuse through Reservoir Augmentation, or IPR.

Click image to enlarge. Recycled water is produced by treating wastewater to a "tertiary" level after which it is used for irrigation and commercial/industrial applications.  The IPR process takes some of the recycled "tertiary" water and puts it through an advanced purification process that renders it similar in quality to distilled water.

Recycled water is produced by treating wastewater to a “tertiary” level after which it is used for irrigation and commercial/industrial applications. The IPR process takes some of the recycled “tertiary” water and puts it through an advanced purification process that renders it similar in quality to distilled water.

 

The report “provides an overview of the technical studies, advanced water purification facility testing, and public education and outreach efforts conducted as part of the Water Purification Demonstration Project. It also presents findings that support the conclusion that a reservoir augmentation project at San Vicente Reservoir would be feasible.”

In short, IPR was shown to be technically sound and, if a recommended large-scale project is approved, would provide the city with about 15,000 acre-feet per year of safe, sustainable, reliable, locally sourced potable water.

A large-scale IPR program would also significantly reduce the amount of wastewater discharged into the ocean. And if a full-scale program works out well, the program could eventually be expanded to build additional satellite advanced purification facilities and recycle 90,000 acre-feet or more per year. That’s 90,000 acre feet less water lost to wastewater discharge.

The City Council enthusiastically accepted the report. Now it needs to decide whether to authorize a full-scale IPR program. That decision will have to wait until Public Utilities Department staff report back in 90 days to the Natural Resources & Culture Committee with a recommended preferred plan. The committee would then forward a recommendation to the full City Council.

The really big part of this story, though, is that San Diego’s wastewater management policy has been a problem for many years and it’s in that context that the potable reuse program needs to be understood.

The Point Loma Wastewater Treatment Plant

Point Loma outfall pipeline where it enters the Pacific.

Point Loma outfall pipeline where it enters the Pacific.

Google Maps view shows the underwater 4.5 mile outfall pipeline and diffuser

The underwater 4.5 mile outfall pipeline and the “Y” diffuser can be seen on this Google Maps image

Because of its arid climate and limited local resources, San Diego needs to import some 80% of its water from hundreds of miles upstream, mainly the Colorado River and northern California. Before San Diego gets its water, upstream municipalities consume some of that water, much of which turns into wastewater. They treat their wastewater and discharge it into the flow of water that continues to downstream communities, where the process is repeated. And repeated.

By the time imported water gets to San Diego, the imported water contains the discharge from some 300 upstream wastewater treatment plants. That should be thought-provoking enough, since San Diego’s water only gets treated in a standard water treatment plant, not an advanced purification facility as is being proposed.

Since there are no users downstream of San Diego, the city discharges its wastewater into the Pacific Ocean from the Point Loma Wastewater Treatment Plant, to the tune of roughly 175 million gallons each day. There’s a problem with that, and not just because so much water gets wasted by dumping it.

The federal Clean Water Act requires wastewater discharges to receive “secondary treatment,” and that’s what the upstream communities do. San Diego, however, does not. Instead it does what it calls “advanced primary” treatment.

Back in 1988, the EPA sued the city for failure to achieve secondary treatment. The city, however, felt that an upgrade to secondary would be unnecessarily and exceedingly expensive (likely more than $1.5 billion that ratepayers would have to fund) and that the parcel of land on which the Point Loma plant lies is so small that it was impossible to expand it.

Ultimately, the EPA agreed to give San Diego some leeway, but as mitigation the city had to develop a water recycling/reclamation program with a capacity of 45 million gallons per day (mgd) and monitor the “advanced primary” Point Loma effluent plume dispersed into the Pacific to ensure discharge quality would fall within specified limits.

The reduction in wastewater discharged from Point Loma along with ocean monitoring would be good for the environment, while recycling would provide more usable water for the city.

Thus was born the 30 mgd capacity North City Water Reclamation Plant (1997) and the 15 mgd capacity South Bay Water Reclamation Plant (2002), along with a “purple pipe” network to distribute recycled water treated at the “tertiary” level to large customers for irrigation and certain commercial/industrial uses.

But things didn’t work out as well as expected.

As reported by a Water Online news report:

In 1997, the San Diego Water Department raided its cash reserves of $65 million intended for fixing the city’s crumbling drinking water system. It used that money to lay 46 miles of purple pipeline to customers in Mira Mesa, Torrey Pines, Scripps Ranch and University City.

Recycled water has turned out to be a big bust. It cannot be sent through existing water lines, it requires expensive construction of new pipelines (“purple pipe”) to distribute the water to customers. Then the customers have to retrofit their existing plumbing or irrigation system with parallel purple pipe systems. The city spent over $18 million to assist customers with that expense. A retrofit of Miramar Nurseries, for instance, cost the city $300,000, according to Hossein Juybari, the city’s recycled water coordinator. The golf course at Miramar Marine Corps Air Station is being replumbed at a cost of $700,000 to the city. The EPA figured the city could reuse 25 percent of the flows of the North City plant by the end of 2003, a goal it set when it granted the city $70 million toward construction. Currently, the city is reusing less than 17 percent of the sewage processed at North City, and water officials say they have no hope of reaching 25 percent anytime soon. By 2010, the EPA goal for the city becomes 50 percent.

[The City has not responded to my request for comment on the veracity of this report]

Another setback to recycling occurred with this 1999 City Resolution ordering the City Manager not to spend money on “water repurification.”

Meanwhile, the City received another EPA waiver for Point Loma in 2001 and lawsuits were filed by San Diego Coastkeeper, the San Diego chapter of the Surfrider Foundation, and the San Diego chapter of the Sierra Club. That history is documented in a memo written by Marco Gonzalez from the Coast Law Group.

According to Gonzalez, there were 3 points to address:

  • Issuance of the waiver in the proposed form violated federal CWA [Clean Water Act] anti-degradation and anti-backsliding regulations.
  • Failure by the City to achieve 45 million gallons per day (MGD) of sewage reclamation was a violation of OPRA [Ocean Pollution Reduction Act], and that merely constructing reclamation capacity without implementing beneficial reuse was insufficient.
  • The plume outfall [from Point Loma] monitoring program was not sufficient to accurately characterize plume migration and impacts.

(Gonzalez’s memo goes into considerable detail about the negotiations and events during that period. It is a fascinating read, posted here with his permission.)

The outcome of these negotiations brought about the following:

1. Acknowledging that the Point Loma wastewater plant lacked sufficient space for expansion, the groups proposed, and the city agreed, to conduct a pilot study of one of the more promising technologies – called Biologically Aerated Filtration (BAF) – to see if it could achieve secondary standards given the quality of Point Loma’s sewage influent and flow demands.

2. A monitoring program by an independent team of technical experts from the Scripps Institution of Oceanography would be assembled to determine the effectiveness of Point Loma’s “advanced primary” treatment.

3. The City would further consider advanced treatment of its reclaimed water for comingling with imported water supplies in drinking water reservoirs [i.e., indirect potable reuse].

Point #3 above resulted in the 2005 Water Reuse Study intended to look at how we might maximize the use of reclamation capacity then existing at North City and South Bay. Following this study, the decision was made to pursue the IPR Demonstration Project. During this same period, a coalition of environmental, business, labor, and trade groups formed the “IPR Coalition” to advance the cause.

______________________________

Years passed as these issues were hashed out. A stronger ocean monitoring program was developed, but the capacity of the two reclamation plants remains underutilized.

At the end of 2008, the City Council overrode a mayoral veto and authorized the raising of funds to pay for the IPR demonstration project (which later got the name Water Purification Demonstration Project).

In 2009, the city needed to apply for a new 5-year EPA waiver, the environmental groups opposed it and promised lawsuits, but Marco Gonzalez and Bruce Reznik offered the City a “non-opposition” to the waiver (very different from “support”) in exchange for the much more in-depth water reuse study considering the possibility of maximizing reclamation and minimizing discharge to the ocean.

With this agreement in place, the city was able to get another waiver. But the EPA and California Coastal Commission warned the city that future waiver requests would not be looked upon favorably.

However, as Mr. Gonzalez wrote in his memo, “the light bulb went off:”

“The goal of the Clean Water Act is not simply to ensure compliance with water quality standards and to achieve the cleanest runoff mandated by federal or state laws. Rather, the structure and purpose of the CWA is geared toward minimizing and when possible eliminating discharges altogether [emphasis added]. Given the value of water in San Diego (at the end of the Colorado River and State Water Project pipelines), the likelihood of continued drought, the technological gains in reverse osmosis, the relatively dirty source water entering our reservoirs, the political and public acceptance for desalination, and a host of other political, economic, and social factors, there is no way San Diego can sustain its current paradigm of pushing sewage down to Point Loma and off into the Pacific Ocean…. Looking at the current paradigm of water supply and sewage conveyance/treatment, the ONLY sustainable option is IPR. With this perspective, our goal became clear. We want to eliminate all discharges to the ocean and maximize IPR as soon as economically, technically, and politically feasible.”

The IPR Coalition, now named the Water Reliability Coalition, continues its work to this day (for some reason the website appears to have been hijacked but they’ve been notified).

Next steps

The clock is ticking for the Point Loma plant. Under the current waiver, the city is already on notice that future waiver requests will not be looked on favorably. Last October, the California Coastal Commission sent a letter to the City expressing “significant concern that the City has not yet committed to milestones and implementation schedules that would enable the City to end the pursuit of future secondary treatment waivers.”

If the city doesn’t demonstrate substantial progress, a new Point Loma waiver might not be easily won and the city could face fines, penalties, and lawsuits as a consequence. The waiver expires July 31, 2015; a renewal application will have to be made in 2014. I’ve learned the Public Utilities Department Director Roger Bailey is now leading a Point Loma waiver strategy team but haven’t been able to obtain more information about it.

San Vicente reservoir before the dam raise project

San Vicente reservoir before the dam raise project

The heightened San Vicente Dam increases the reservoir capacity from 90,000 acre-feet to 242,000 acre-feet.

The heightened San Vicente Dam increases the reservoir capacity from 90,000 acre-feet to 242,000 acre-feet.

The City Council’s acceptance of the IPR project report is certainly progress. But in accepting the report, several City Council members indicated a desire to also explore Direct Potable Reuse, or DPR as a less expensive alternative to IPR. Whereas the IPR proposal involves construction of an expensive pipeline to the San Vicente Reservoir (which, incidentally, has been vastly expanded), DPR would send the water directly to the potable water treatment plant (likely Alvarado), using a much shorter pipeline, with no detention time in a reservoir. That could save more than $200 million in pipeline construction, but also raises questions about safety and regulatory approval.

So much time, effort, and expense has gone into clearing regulatory hurdles for the IPR project, that DPR, for all its attractiveness, could be a distraction from work that is still needed for IPR. The California Department of Public Health (CDPH) and the San Diego Water Board have indicated general acceptance of San Diego’s IPR project, but it is many years away from regulatory approval for DPR. Senate Bill 918 requires CDPH to investigate the feasibility of developing uniform water recycling criteria for direct potable reuse and to provide a final report on that investigation to the legislature by December 31, 2016. The regulations will come some years after that.

One option could be to proceed with a large scale IPR program with a pipeline to San Vicente as already envisioned. Subsequently, satellite advanced treatment plants could be built for DPR. That would allow San Diego’s waiver application to say we’re making substantial progress. It would also allow time for CDPH to issue regulations for DPR…it seems likely that won’t happen for many years beyond 2016.

Assuming the preferred path is IPR now and DPR in the future, the issue is still how to get things moving? What questions need to be addressed?

At the City Council meeting, PUD’s Marsi Steirer said the cost of IPR would not only be lower than the cost of desalination, it would be cheaper than imported water (around $1,000 per acre foot). That’s competitive with the price of imported water, but according to the Project report the actual cost is about $2,000 per acre foot—around where desalination is priced. Reading from the report:

“If full-scale reservoir augmentation is implemented, the city would not need to build a 7 million gallon wet weather storage facility to attentuate wastewater flow to Point Loma; reduced overall flow to Point Loma would reduce annual operations and maintenance costs at Point Loma plant and Pump Station 2 which conveys flows to Point Loma. Water salinity in the city water supply would be lower, potentially reducing costs further. Taking these factors into account PUD estimates the NET cost for IPR would be about $1,000 per acre foot.”

But wastewater has to be treated at Point Loma or at the North City reclamation plant, so are the savings really that great or is the cost just being shifted from Point Loma processing to North City processing? It will be interesting to see if the sewage treatment portion of our water bill shows a price decrease. So, next steps would appear to be:

  • IPR would benefit both water and wastewater systems, therefore proportional share of costs needs to be determined in order to prepare water and wastewater rate cases
  • Determine a contracting mode
  • Refine pipeline alignment, which represents an estimated 60% of total implementation cost
  • Coordinate with regional wastewater and reuse objectives including Point Loma waiver expiration in 2015
  • Monitor development of DPR regulations

In any event, it doesn’t seem wise to argue that we should embark on IPR because it is cheaper. It may or may not be less expensive than desalination or imported water in the long run, but IPR is clearly the right thing to do.

______________________________

I welcome any comments that can correct and improve on this report.

Some sources for this story that may be of interest:

 

Posted in Water, Water Purification Demonstration Project | Tagged: , | 8 Comments »

Advances in water recycling approved by San Diego City Council NR&C Committee

Posted by George J Janczyn on May 24, 2012

The San Diego City Council Natural Resources and Culture Committee (NR&C) approved on Wednesday (May 23) two substantial reports that recommend how recycled water can be used more effectively in the future as San Diego struggles with ways to reduce its extreme dependence on imported water that is becoming an increasingly expensive and less reliable source [link to the agenda].

According to the Recycled Water Master Plan, its purpose “is to evaluate opportunities to maximize non-potable reuse [of recycled water treated to tertiary standards] if IPR (Indirect Potable Reuse) projects are not pursued” [emphasis in italics is mine].

IPR refers to a series of advanced treatment processes applied to the tertiary water that results in purified water that is in essence distilled water and then to store that water in an underground aquifer or to blend it with imported raw water in an above-surface reservoir.

Nonpotable recycled water, of course, is limited to use in specific agricultural, irrigation, and certain industrial settings. A separate pipeline infrastructure must be built to deliver that water (“purple pipe water”), and you definitely can’t drink it.

This blog post, therefore, focuses on the subject of the companion to the Recycled Water Master Plan, the City of San Diego’s Recycled Water Study.

After considering a number of options, the Recycled Water Study mainly examined two possible ways IPR projects can be pursued in San Diego: 1) use IPR water to recharge groundwater resources, or 2) mix it with imported water that is piped into and stored in local reservoirs (sometimes referred to as “reservoir augmentation”). IPR, as you probably know, results in water that is of higher quality than the water we import from the Colorado River and Northern California and it can be used for any purpose, including for drinking, and delivered using our existing potable water infrastructure.

Another option examined in the Recycled Water Study, Direct Potable Reuse (DPR)–which would deliver the purified recycled water directly into the water distribution system instead of mixing it with imported reservoir water—has not been well-studied and would be difficult to implement without the development of new statewide regulations, so the study concludes it is not on the table for the near future in San Diego.

The Recycled Water Study envisions that continuous increases in the price of imported water along with decreased reliability and availability of imported supplies will soon make the relatively expensive IPR process competitive with imported prices (it’s already competitive with, if not cheaper than, the cost of desalinated water)…and will eventually be dramatically less expensive than imported supplies.

The Recycled Water Study was the outgrowth of an agreement between San Diego Coastkeeper, the San Diego Chapter of the Surfrider Foundation, and the City of San Diego, whereby the environmental groups agreed not to oppose the EPA’s Regional Water Board’s, and Coastal Commisssion’s approval of San Diego’s Clean Water Act waiver that allows the Point Loma Wastewater Treatment Plant to continue discharging into the ocean the sewage receiving only Advanced Primary instead of Secondary treatment. The waiver expires in 2015, with an application due a year before expiration, so time is of the essence.

If San Diego chooses not to pursue upgrades to the Point Loma treatment plant to full Secondary treatment standards before the expiration of the current waiver, there is widespread speculation that the governmental agencies are not likely to renew the waiver and the city could face huge financial penalties AND be faced with a full upgrade to the treatment plant.

Upgrading Point Loma to Secondary treatment at its current load would be exceedingly expensive partly because of the large wastewater flow it receives and partly because there’s little room to expand on the limited hillside space it occupies facing the ocean along Point Loma’s western slope.

So…the Recycled Water Study envisions that if enough water is recycled, particularly via the advanced IPR treatment process, a good deal less wastewater would be sent to Point Loma. Point Loma then would be burdened with treating less wastewater and it would be much less expensive to upgrade to Secondary treatment standards. In that scenario, the city could even apply for federal financial assistance to upgrade Point Loma to Secondary treatment. If nothing is done and the waiver expires, the city would face large fines, be forced to upgrade to Secondary treatment at greater ratepayer expense and would not be eligible for federal financial assistance.

The Recycled Water Study concludes that groundwater recharge opportunities are extremely limited given San Diego’s geography. As such, using IPR water for reservoir augmentation is the most realistic option for San Diego to incorporate purified recycled water into its its potable water portfolio.

(the above photos show a portion of the advanced treatment facility being used for the Water Purification Demonstration Project. Click to enlarge)

Therefore, a Water Purification Demonstration Project examining the feasibility of using the IPR process focusing on reservoir augmentation by the City of San Diego is currently underway. A prototype advanced treatment facility at the North City Water Reclamation Plant is producing a limited amount of IPR water while a parallel scientific study is being conducted on the feasibility of blending IPR water with imported water in the San Vicente Reservoir.

When the Demonstration Project is completed, a number of unfinished regulations and guidelines addressing IPR must be approved by federal, state, and local agencies before San Diego can implement IPR reservoir augmentation on a large scale.

One problem with the NR&C vote on Wednesday, though, is that the committee simply “approved” both reports to advance to the City Council. The motion to approve both plans made no recommendation as to which plan to implement; that is, whether to commit to nonpotable recycling in the future, or recommend a combination of nonpotable recycling and IPR projects.

This decision tree from the Recycled Water Master Plan illustrates the issue:

There was, however, some indication of the direction towards which the committee leans on this question.

During discussion before the vote, Councilmember Sherri Lightner appeared to favor developing a balanced plan, incorporating nonpotable and potable recycled water, especially since a significant amount of nonpotable water infrastructure already exists and there are contracts and plans already in place to expand that form of recycled water use.

Another issue is that the Recycled Water Study raises the possibility of a much larger capacity facility to produce the advanced treatment product water (or several new satellite IPR facilities) to achieve a goal of producing as much as 100 million gallons per day (GPD) of IPR water, and it implies that because the San Vicente Dam Raise Project will more than double the capacity of the reservoir, there would be capacity to handle it.

That raised a question in my mind, which I decided to ask during the public comment portion of the NR&C meeting: the fact being that the County Water Authority (CWA) is building the San Vicente Dam raise and it will own the rights to the additional capacity. Would CWA buy IPR water from the city or fill it with imported water? And if all the water in the reservoir will be mixed, would it then be delivered to all the CWA member water agencies…and would they be agreeable? I also suggested that due to the close proximity of El Capitan Reservoir (currently San Diego’s largest), why not consider using both San Vicente and El Capitan as receiving reservoirs for IPR water?

Later, during committee discussion, Councilmember and committee chair David Alvarez asked PUD staff about that. Assistant PUD Director Marsi Steirer allowed that San Diego would only be adding IPR water to the portion of the reservoir capacity that the city owns…and that if the city eventually did produce up to 100 mgd of IPR water, its portion of San Vicente reservoir could consist entirely of IPR water. My question regarding El Capitan was not addressed at that time, but I’ve since learned it was a point of discussion during production of the report.

Ms. Steirer later sent me email addressing that question. With her permission, I’m reprinting a portion of her reply here:

There are two principle reasons El Capitan Reservoir is not as good a choice for reservoir augmentation as San Vicente Reservoir: storage volume and distance.

Storage volume
The greatest value – the best use – of El Capitan Reservoir is to capture local runoff. The El Capitan Catchment [the land area that drains to the reservoir] generates the greatest amount of runoff of any reservoir in the San Diego region. In our region rainfall and runoff are highly variable. Much of El Capitan’s runoff occurs in the occasional high rainfall year; something like two years per decade have abundant runoff and the reservoir fills up. We then store this runoff water for use over several years. For this reason, our operational scheme for El Capitan is to keep storage space available in the reservoir in anticipation of high runoff years. The average runoff to El Capitan is 28,000 AFY.

San Vicente Reservoir, on the other hand, is primarily filled with imported water. The San Vicente Catchment does not generate much runoff. The average runoff to San Vicente is 4,000 AFY.

Basically, we keep San Vicente full with imported water and El Capitan relatively empty to capture local runoff.

[Note that in recent years – starting in 2008 and extending to 2018 – El Capitan has been more full than typical. San Vicente has been drawn down to facilitate construction of the new dam. We have compensated by storing more imported water at El Capitan. When San Vicente is completed and refilled, we will return to the typical operation at El Capitan.]

So, while El Capitan has a large total capacity [113,000 AF] the amount of water typically stored there is relatively small. The average long-term storage in El Capitan is about 40,000 AF. Compare this to the average storage in the future expanded San Vicente of about 180,000 AF.

San Vicente is a better choice for reservoir augmentation simply because it is larger. El Capitan, because it stores a smaller volume, does not offer the same level of retention, blending, and response time.

Distance
Constructing a pipeline to carry IPR water to El Capitan would be a difficult and costly endeavor. Conveying IPR water from North City to El Capitan would require eight to twelve miles of additional pipeline, and it would necessarily route through difficult terrain and environmentally sensitive areas.

But El Capitan isn’t entirely out of the question: Ms. Steirer also pointed out that the San Diego Reservoir Intertie Study although currently on hold due to U.S. funding constraints, includes plans to consider a connection between San Vicente and El Capitan. The conclusion, she says, is “if an intertie were established either directly or indirectly between San Vicente and El Capitan, we assume that it could accommodate a larger capacity IPR/RA project.”

Councilmember Alavarez also commented that he believes that IPR is 100% the only solution he believes will work to solve the issue of increasing local water supply and reliability, as well as dealing with the Point Loma plant upgrade.

It’s not certain when this item will be docketed for the full City Council, but a condition of the Coastal Commisssion’s approval of the last waiver was that the Study be presented in approximately two years, and that deadline is fast approaching. The City is also pressured to act quickly, because even if the Demonstration Project concludes successfully and the city promptly moves to develop a large-scale IPR operation, it certainly won’t be finished, and most likely construction wouldn’t even be started, by 2015. Therefore, the only way for the City to be assured it will qualify for one or more additional waivers would be to get an approval and timeline in place to implement a significant amount of IPR, and thus justify the delay in upgrading the Point Loma treatment plant.

 

Related local news reports:

 

Posted in Environment, Water, Water Purification Demonstration Project | Tagged: , , , | 3 Comments »

The water subsidy for golf courses ‘scandal’

Posted by George J Janczyn on April 17, 2010

Balboa Park Golf Course

Balboa Park Golf Course is not yet using reclaimed water

How your water rates subsidize golf courses” is the headline in a recent Voice of San Diego article by Rob Davis that will probably stir up some indignation around town. The article says that “475 businesses, homeowners associations, golf courses and public agencies” get a 78% discount on reclaimed water which is subsidized by regular water users. The article cites Michael Shames, executive director of UCAN, who suggests that discounted prices for reclaimed water users may be illegal, and that “City Councilwoman Donna Frye called it “out-of-whack” and promised to hold a public hearing on it.” In a subsequent PBS Editors Roundtable discussion, Voice of San Diego executive editor Andrew Donohue said a normal discount for reclaimed water should be only 10% and that the City had been keeping the subsidy for industrial use a secret.

I really don’t see a scandal here.

North City Water Reclamation Plant

First, the discount isn’t a secret (although details on its financial impact may be hard to obtain). The City’s Guaranteed Water for Industry Program is where the discounted water has been publicly documented [the discount is also documented here]. Initially the discount was only for businesses certified under the program, but presently the $0.80 per HCF price (which they wrote was a 50% discount) applies to all purchasers of reclaimed water (with the exception of Poway which is charged more because it didn’t pay certain capacity fees). [There is no discount for the fixed base fee, however. All water users pay the same base fee.]

Second, the suggestion that one group is subsidizing another group sidesteps the fact that it’s looking at two classes of water–it’s not one group of potable users subsidizing another group of potable users. It may be true, though, that if reclaimed water is being sold at a loss the entire Water Department budget has to absorb that loss [or possibly the Wastewater Department in which case the sewer fee would be the water customer revenue source supporting the recycled water sales].

Third, to use reclaimed water requires an expensive investment in purple pipe infrastructure and plumbing, so a discount in the water price certainly makes that decision by potential new customers a little easier.

Ocean outfall at Point Loma

Last, as things stand, San Diego’s water reclamation plants remain unable to sell all the water they can treat. The Voice’s article briefly mentions the 2001 City Council decision to discount the water in order to attract buyers, but the lack of buyers is still a very important fact to consider. A large amount of usable reclaimed water they can’t sell, even today, is pumped to the Point Loma Wastewater Treatment Plant and disposed of through the ocean outfall into the Pacific. Considering the substantial infrastructure expense and the amount of treated water going to waste, it only makes sense that large water consumers like golf courses should be targeted first as customers for reclaimed water. Without a discount for the reclaimed water, businesses have less incentive to stop using potable drinking water for their irrigation and industrial needs. [Consider, too, that the City is under an EPA mandate to maximize the reuse of the water treated at this plant]. Do we really prefer to continue sending precious potable water to golf courses and industry while treating reclaimed water to usable standards and then dumping it in the ocean?

Yes, we need to reexamine the discounted price for reclaimed water; that price probably should at least be adjusted for inflation and operating costs. And in fact, the Water Department is currently performing a Recycled Water Pricing Study which is due sometime this year.

As for additional outlets for surplus reclaimed water, I completely support the Indirect Potable Reuse Study that is looking at advanced purification of reclaimed water to bring it to a potable drinking water standard. That project envisions a 1 million gallon per day operation during the study, and if deemed feasible and if approved by the Mayor and Council, a full-scale IPR/Reservoir Augmentation project with a plant adjacent to the North City Water Reclamation Plant and a pipeline to San Vicente Reservoir, would generate approximately 16 MGD. But convincing the population to agree to recycled drinking water isn’t made easier when the media keeps calling it “toilet to tap.” The Voice’s “…use its sewage to boost drinking water supplies” is just as bad. Surely they can do better than that. A good substitute for the awkward phrase “indirect potable reuse” that I’ve seen used is “repurified water.”

So, we still need to find a way to stop throwing recycled water away — we need to find new buyers for that water. I say we should definitely make a realistic adjustment to the discount for reclaimed water, but not eliminate it. In the long term reclaimed water needs to make a big difference in the availability and reliability of drinking water supplies for San Diego and we should support incentives to increase its use.


Apr 20, 2010: The Voice continues to press its complaint with The unanswered golf course subsidy question: “The city knows the answers to those questions — it just isn’t sharing.”

Looking at the Recycled Water Cost Study draft report (the ‘confidential city study‘ that the article refers to), I see that it recommends the recycled water rate to significantly increase from the present $0.80 per HCF to $1.46 in 2010, $2.03 in 2011, and $2.66 in 2012. The report also states that the recycled rate increases are expected to eventually allow the potable water system to recover all contributions it is making to support the recycled system discount.

 

Posted in Environment, Indirect potable reuse, Water | Tagged: , | 2 Comments »

Framework for informed planning decisions regarding indirect potable reuse and dual pipe systems

Posted by George J Janczyn on April 16, 2010

A Request For Proposals (RFP) recently issued may be of interest to anyone following San Diego’s Indirect Potable Reuse Study. The project is sponsored by the WateReuse Foundation as part of the Foundation’s Solicited Research Program. The Bureau of Reclamation is a funding partner for the project.

“The project objective is to develop a tool to help enable utilities to make an informed and sustainable decision regarding their investment into reuse options at the project, city, or regional level. Specifically, this tool will address issues, advantages, and obstacles in the implementation of an Indirect Potable Reuse (IPR) project, dual pipe reuse system with or without point of use treatment, or combinations therein to enable utilities to objectively plan projects against triple bottom line objectives. This will be accomplished by creating a planning framework, such as a decision tree matrix, that considers all aspects — social and legal, economic, and environmental — of IPR and dual pipe reclaimed water distribution systems that can include point of use treatment requirements.”

Click here to see the complete RFP.

 

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City Council to vote on recycled water pipeline

Posted by George J Janczyn on February 21, 2010

North City Water Reclamation Plant

[Feb 24 update: The resolution was approved as part of a package of consent items during the meeting, which usually means no major objections were anticipated]

The San Diego City Council will vote on Tuesday whether to adopt a resolution approving the plans and specifications for the Carmel Valley Recycled Water Pipeline Construction Project and to authorize advertising for bids on a construction contract. Up to $4,730,000 would be approved to pay for the project (see City Council Docket Item 100).

The pipeline will consist of approximately 10,000 linear feet of 8-inch to 12-inch diameter pipeline to provide an extension to serve recycled water from the North City Water Reclamation Plant to the Meadows Del Mar Golf Course, Palacio Del Mar Home Owners Association and future customers in the western portion of Carmel Valley.

The project is to assist the City in carrying out Phase II of the 2000 Water Reclamation Master Plan which states the City will attempt to achieve the beneficial use of 50% of treated wastewater by the year 2010. That goal was related to the City’s EPA waiver from having to provide secondary treatment at the Point Loma Wastewater Treatment Plant, the latest which was just renewed last October. That waiver committed San Diego to treat 45 MGD of wastewater by 2010 (note there’s a difference between ‘treated’ and ‘used’).

According to the 2005 Recycled Water Master Plan Update, the goal was to reuse at least 12 million gallons per day of water from the North City Water Reclamation Plant (the plant treats about 22.5 MGD, with the excess sent to Point Loma for disposal at sea). At the time of the 2005 update, the actual amount reused amounted to only 6 MGD. I haven’t learned what the current usage for 2010 is, but according to the 2005 Update, if implemented as described, the phased system expansions outlined in the reclamation plan would allow the City to meet the 12 MGD water reuse goal by 2010. Toward that end, the proposed pipeline project is estimated to supply approximately 300 acre feet of recycled water per year according to the city council docket (1 acre foot = 325851 gallons).

Supporting documentation for the Council agenda item: Inviting Bids for Carmel Valley Recycled Water Pipeline Construction Project (Carmel Valley Community Area. District 1.)

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San Diego recycled water presentation at UCSD

Posted by George J Janczyn on January 14, 2010

A seminar on San Diego’s water recycling program on Jan. 13 included an overview of the city’s Indirect Potable Reuse/Reservoir Augmentation Demonstration Project currently underway. The seminar was sponsored by UCSD’s Sustainability Solutions Institute. Marsi Steirer, Deputy Director of Long Range Planning and Water Resources, San Diego Water Department, was the featured speaker. A copy of the slides from her presentation is embedded below.

Although much of the presentation recapped information already available on San Diego’s Water Department website it was a good opportunity to review the project highlights in person and to hear the question/answer session afterwards.

One thing that caught my eye was the slide indicating that San Diego imports about 75% of its water, because most water department web pages I’ve seen indicate between 85-90%. Ms. Steirer explained that the number varies from year to year and the higher figure reflects a long-term average whereas the lower number is an “actual number.” Also I was disappointed that the city’s current water recycling rate of 3.1% was projected to increase only to 4.7% by 2030. Responding to that, Marsi stated that the figures in the slide were based on a 2005 planning document and that the numbers will likely change after the demonstration study is completed and the city council approves new goals. One person wondered if it makes sense to install a separate “purple pipe” infrastructure for recycled water if there is a possibility that all recycled water will eventually receive advanced purification to potable standards, in which case purple pipes wouldn’t be needed any more. Marsi indicated that they’re still struggling with that issue.

Another opportunity for the public to hear Ms. Steirer give a presentation on this topic is coming up on Wednesday, January 20, at a Surfrider Foundation meeting to be held at Forum Hall in University Towne Center.

UPDATE Feb 2, 2010: If you missed both of the above presentations, the Surfrider Foundation has a video of their Jan. 20 session.

(navigate the slides with the scroll bar or buttons at bottom, or point at slide and use mouse wheel)

 

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Water prices in San Diego: at least there’s water to pay for

Posted by George J Janczyn on January 5, 2010

Colorado River Aqueduct

We’ve known it was coming and now that January is here, the next water rate increase is taking effect. Every time we get an incremental water rate increase, the news media jumps on the story and before long the comments threads are alive with people complaining about being ripped off for using water or for conserving water. Sigh.

My 3-member family lives in a 2600 sq. ft home on a 14,700 sq. ft. landscaped lot near Lake Murray and we used 12 HCF in the last two-month period (to me it still seems too much but I think it compares well with sparing consumers). The water used fee was $35.72 for those two months. There’s also a base fee for another $35.18 regardless how much water was used, but that’s money for fixed operating expenses. Compare that with our nonessential Cox Cable bill which is $108.67 per month for TV alone. From that perspective, even a doubling of the water used fee would not be a big deal, especially knowing it’s for a necessity of life.

One water-related fee that I expect to show dramatic increases in the future is the sewer fee, which for our home right now stands at $100.21 per billing period. That’s also a fixed fee, charged regardless of amount of water used. It’s very expensive to treat sewage and the price reflects that. Still, San Diego is not yet treating sewage at the Point Loma facility to secondary standards as required by the Clean Water Act, so when the city is finally forced to take that step we will certainly see the sewer fee rise, and not just a little. Further, if our city is going to succeed in further reducing its reliance on imported water, it’s going to have to expand its water recycling program. Water recycling is part of the wastewater treatment system and additional investment in that will also mean higher sewer fees.

Iron Mountain Pump Station

I’m certainly concerned about paying more for water and related infrastructure expense, but I just don’t see widespread administrative fraud or negligence there. My big concern is how precarious our existence here is because we rely so heavily on imported water. There’s a huge water delivery infrastructure bringing us water from northern California and the Colorado River, but it’s very fragile at many points. A major disruption to the delivery system could be devastating. That’s what really scares me, and it’s why I recently wrote this opinion on water reuse last month. When it comes to its water, increased self-sufficiency should be San Diego’s number-one priority.

 

(Photo of Iron Mountain Pump Station courtesy of Ron Gilbert from http://www.ipernity.com/doc/ronslog/1350447. Photo of California Aqueduct found widely reprinted online without attribution, possibly originated from the State Department of Water Resources)

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Water recycling at Viejas

Posted by George J Janczyn on June 27, 2009

Viejas water storage tanks

Viejas water storage tanks

Yesterday I went up to Viejas to find out about their recycled water system.  What’s pretty cool is that they capture 100% of their wastewater, put it through their nearby water treatment plant, and then store it in large water tanks (partially hidden behind a rock sculpture near I-8) to use for landscape  irrigation and as a reserve for firefighting.   Viejas is totally dependent on an underground aquifer for potable water–they have no outside water sources.

Viejas water treatment plant

Viejas water treatment plant

Aside from the wastewater recycling system are four small check dams creating ponds in the large pasture in the valley behind the casino.  That water comes from local runoff and the ponds allow water to percolate into the aquifer and provide drinking for grazing cattle and other wildlife. You can see the ponds in this satellite photo. A sign next to a small grove of fruit trees indicates they are watered with recycled water; however a staff member at the public works department told me they need to take the signs down because they no longer use recycled water for the fruit and that there isn’t enough recycled water to supply additional uses in the reservation aside from the casino and firefighting reserve. When I observed that the reservation has long undergone a tight water situation and it must be difficult, he said that on the other hand it’s nice not having to depend on outsiders.

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