MEC&F Expert Engineers : LIQUID GOLD: Calinfernio's prolonged drought is forcing Central Valley farmers to turn to sewage plant effluent water to irrigate crops.

Friday, August 26, 2016

LIQUID GOLD: Calinfernio's prolonged drought is forcing Central Valley farmers to turn to sewage plant effluent water to irrigate crops.





California farmers turn to sewers for water









California's prolonged drought is forcing Central Valley farmers to scramble for water to irrigate crops. One agency is even turning to a sewage plant to meet demand. (KGO-TV)

Thursday, August 25, 2016 08:24PM
PATTERSON, Calif. (KGO) -- California's prolonged drought is forcing Central Valley farmers to scramble for water to irrigate crops. They have to be creative. One agency is even turning to a sewage plant to meet demand.

Just outside Modesto, farming communities like Patterson are facing a crisis. There's barely enough water to irrigate crops, so little, that about a quarter of the local farms have stopped growing anything.

"We have over 12,000 acres that has not been farmed for the last several years, and that has very sudden and severe economic ripple effects through these small communities," said Anthea Hansen of the Del Puerto Water District,

The Del Puerto Water District is responsible for supplying water to a swath of land 50 miles long from Tracy to Santa Nella. The district gets all its irrigation water from the Delta-Mendota Canal. The contract allows them to take more than 140,000 feet.

"This year, we're five percent of that," said Hansen.

But Del Puerto will soon tap an unexpected source, used water from the nearby Modesto sewage plant.

The city flushes nearly 15 million gallons of water down the drain every day. That's roughly 15 percent of what nearby Del Puerto's needs. Modesto's waste water plant recently underwent an $150 million upgrade, making the sewage recyclable.

William Wong is with the City of Modesto Utility District. He said, "Right now, recycled water is what we call in the industry, new water."

Senior Wastewater Treatment Plant Operator, Ben Koehler said, "What we are accomplishing here is taking raw wastewater and removing all the pollutants in order to produce clean affluence on the other end."

That recycled water gets discharged into the San Joaquin River, or pools near the river.

Under a new agreement, a $100 million pipeline will divert that water to farmers.

"It's safe for irrigation on crops," Koehler said.

Hansen pointed out that it is used in other parts of the state. "If people have been eating strawberries, or artichokes over the last decade plus, from the Salinas Valley, that's what's been used on it," he said.

But the project will take the idea to a much bigger scale. "This will be one of the largest beneficial water reuse projects in the country," said Wong.

Other Central Valley communities are watching closely to see what happens.

"I get a lot of calls, people wanting to know how do you do it? Where do we start?" Hansen said.

It will start Friday when the new pipeline breaks ground.

Written and Produced by Ken Miguel


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Frequently Asked Questions

FAQs regarding general Information

Q: What is the Watsonville Area Water Recycling Project?
Q: Where is it located?
Q: Why do we need it? What are the benefits?
Q: When does the project start?
Q: Is the water safe?
Q: Where is the water from? How much water?
Q: If I need more information, who should I contact?

FAQs regarding the need for the Recycled Water Facility

Q: Why is the project needed?
Q: How does water recycling slow seawater intrusion?
Q: Besides slowing seawater intrusion, what are other benefits of water recycling?

FAQs about the Water Recycling Process

Q: Is recycled water safe for use on crops?
Q: How is wastewater converted into safe water?
Q: What kind of testing is done on the treated water?
Q: How are the byproducts of wastewater recycled?
Q: How much water do you discharge into Monterey Bay?
Q: How much water do you treat?
Q: Where does the recycled water go?
Q: What is the quality of the recycled water?
Q: What crops use recycled water?
Q: How much does the water cost the growers?
Q: How much total water do the growers use?
Q: Has the recycled water you’re delivering ever been contaminated?
Q: When was the last time you couldn’t deliver the water needed?
Q: Where else in the country/world is recycled water used on crops?

FAQs about the Recycled Water Facility

Q: When did the PVWMA start making deliveries from the Watsonville Recycling Plant?
Q: How much did it cost to build the project?
Q: Where did the construction funds come from?
Q: What training do employees receive?
Q: Are there other California water recycling projects?

 

OVERVIEW

Q: What is the Watsonville Area Water Recycling Project?
A: The Pajaro Valley Water Management Agency (PVWMA) partnered with the City of Watsonville to introduce the Watsonville Area Water Recycling Project as part of the agency’s long-term plan to meet the water needs of our region. This recycling project will provide nearly a quarter of the water needed to halt seawater intrusion on coastal lands and is a cost-effective way to maximize local resources before turning to other supplemental sources. The recycling project exemplifies municipal and agricultural cooperation to protect water resources.

Q: Where is it located?
A: The recycling project is located in Watsonville, California.

Q: Why do we need it? What are the benefits?
A: The Watsonville Area Water Recycling Project is vital to our region. California’s ongoing drought emergency requires us to use every tool at our disposal to effectively manage our water resources. Providing a constant and reliable supply of recycled water that is available year after year, regardless of weather conditions, will help protect the $400 million agricultural industry and thousands of agricultural jobs in the Pajaro Valley.

Q: When does the project start?
A: Water deliveries began in April 2009.

Q: Is the water safe?
A: The Watsonville Area Water Recycling Project uses well-established processes that are employed throughout the United States and globally. California has strict standards in for regulating recycled water use and the Watsonville plant meets all state and federal requirements for recycled water quality and safety.

Q: Where is the water from? How much water?
A: Water used in homes and offices travel through pipes to the recycled water facility where it is cleaned through physical, chemical and biological processes. The recycled water facility will produce 4,000 acre-feet of recycled water (new to the basin) to be blended with approximately 2,000 acre-feet of “blend” water, for a total of 6,000 acre-feet per year. That water, delivered through our coastal distribution system, will be able to irrigate a portion of more than 6,000 acres during spring, summer and fall months. It is considered “new” water since it otherwise would be discharged into Monterey Bay National Marine Sanctuary. The nearby Castroville water recycling project safely delivers more than 13,000 acre-feet to farmlands each year.

Q: If I need more information, who should I contact?
A: For more information, please call 831-722-9292 or e-mail info@pvwma.dst.ca.us.

WHY IT’S NECESSARY

Q: Why is the project needed?
A: The Watsonville plant is a key part of the PVWMA’s long-term plan to meet the water needs of our region. Recycled water is a constant and reliable supply that is available year after year regardless of weather conditions. In addition, California’s ongoing drought emergency requires us to use every tool at our disposal to effectively manage our water resources. Recycling is a cost-effective way to maximize local resources before turning to other supplemental sources.

Q: How does water recycling slow seawater intrusion?
A: Without recycled water, the underground water supply will diminish more quickly, speeding intrusion of seawater and ultimately devastating our farmland. About 18,500 AFY of pumping needs to be replaced near the coast to halt seawater intrusion. The Watsonville plant will provide nearly a quarter of the water needed to halt seawater intrusion on coastal lands.

Q: Besides slowing seawater intrusion, what are other benefits of water recycling?
A: Water recycling protects the environment because almost all of the byproducts can be used for irrigation and electricity generation, and any residual solids can be converted to biosolids for use as soil amendments. In addition, because the recycled water is used for crops, plants can benefit from the nutrients in the recycled water, so fewer commercial fertilizers may be used.

THE WATER RECYCLING PROCESS
Q: Is recycled water safe for use on crops?
A: Yes, recycled water is perfectly safe for use on agricultural crops and for a wide variety of other domestic uses. The recycling process is safe, well-established, and highly regulated, and the water meets all state and federal requirements for recycled water quality and safety, including the more stringent standards here in California. Recycled water is a common source of supply for growers across California and other Western states. The nearby Castroville project has safely delivered more than 13,000 acre-feet of recycled water to farmlands each year for more than a decade without one single permit exceedance.

Q: How is wastewater converted into safe water?
A: Wastewater is conveyed from homes and businesses to pump stations in the area. The wastewater is then pumped to the Watsonville Wastewater Treatment Facility where it receives treatment by Primary, Secondary and Tertiary processes.  Primary treatment consists of gravity separation, while secondary treatment uses microscopic organisms found naturally in the environment to remove contaminants. The tertiary, or recycled water treatment, moves secondary treated wastewater through the water recycling facilities where it is filtered and disinfected with Ultra Violet light disinfection. After treatment, the recycled water is held temporarily in a one million gallon storage tank before it is distributed to farmlands via an underground pipeline system.

 Q: What kind of testing is done on the treated water?
A: Turbidity, Total Coliform, Carbonaceous Biochemical Oxygen Demand, Total Suspended Solids, Total Nitrogen, Ammonia, pH, Total Dissolved Solids, Sodium, Chloride, Sulfate and Boron and more...

Q: How are the byproducts of wastewater recycled?
A: There are three byproducts of wastewater recycling: recycled water, biosolids and methane gas. Recycled water is used for irrigation; biosolids can be used as soil amendments, reused at the neighboring landfill as cover material or are turned into compost by mixing it with green waste, such as lawn clippings; and methane gas can be generated by anaerobicically  digesting the solids removed during the primary, secondary and tertiary processes.  Methane gas is used to fuel the wastewater plant’s cogeneration engine which produces 90 percent of the power used for primary and secondary treatment.

Q: How much water do you discharge into Monterey Bay?
A: Currently, 7,130 AF of treated wastewater is discharged to the ocean each year. 

Q: How much water do you treat?
A: Up to 7.7 million gallons per day is recycled.

Q: Where does the recycled water go?
A: Recycled water is distributed local farmland near the coast by the coastal distribution system. During the rainy season when the growers do not need as much treated water, it is safely discharged one and half miles off shore into the Monterey Bay as highly-treated secondary effluent.

Q: What is the quality of the recycled water?
A: Recycled water is highly disinfected, as well as similar in appearance and safe like potable water, but has the added benefit of nutrients that are useful to plants, making it possible for farmers to use less commercial fertilizers.

Q: What crops use recycled water?
A: Artichokes, broccoli, cauliflower, head and leaf lettuce, strawberries, celery, fennel, Brussels sprouts, radicchio, rapini and cardoni.

Q: How much does the water cost the growers?
A: Growers are assessed fees based on the amount of water used and acreage. Using recycled water is less expensive than using well water for irrigation.

Q: How much total water do the growers use?
A: Individual growers require different amounts of water, depending on their land size, crops, rainfall and other climate conditions. Growers typically require between one and one-half and two acre-feet of water for each acre of crop each year.

 Q: Has the recycled water you’re delivering ever been contaminated?
A:  Our rigorous monitoring program and testing of the water allows us to ensure that we deliver clean, safe water for irrigation.

Q: When was the last time you couldn’t deliver the water needed?
A: All growers have gotten all the water they need every day. Occasionally, growers are asked to take water at a different time of day.

Q: Where else in the country/world is recycled water used on crops?
A: Recycled water is used throughout the world. In the United States most facilities are in California, Florida, Arizona, Nevada and Texas. The PVWMA efficiently and economically manages existing supplemental water supplies for growers in the Pajaro Valley Basin. It manages the entire groundwater basin which overlaps four major jurisdictions: the city of Watsonville, and Santa Cruz, Monterey and San Benito counties.

THE FACILITY
Q: When did the PVWMA start making deliveries from the Watsonville Recycling Plant?
A:  April 2009

Q: How much did it cost to build the project?
A: Total construction was $48 million. Water recycling facilities construction cost $24.5 million, plus distribution system.

Q: Where did the construction funds come from?
A: The construction was funded by the City of Watsonville, federal and state loans, grants and bonds.

Q: What training do employees receive?
A: All plant and distribution operators receive initial and ongoing training on the operation and maintenance of the water recycling system.  Required personnel also maintain the proper levels of state certification.

Q: Are there other California water recycling projects?
A: Yes. In addition to the 250 water recycling systems currently operating in California, dozens of new projects are in the works. Current operating projects include East Bay Municipal District, South Bay Water Recycling Program, Padre Dam Water Recycling Facility, Santa Rosa Subregional Reclamation System, Irvine’s Commercial Reuse Project and San Diego Regional Water Reclamation System.