WRCRWA Updates: March 6, 2018

Energy Efficiency at WRCRWA Yields $500,000 Rebate from Edison

WRCRWA SCE Incentive
Southern California Edison recently awarded WRCRWA with a rebate check for its energy efficiency efforts at the WRCRWA Treatment Plant. Since first being formed in 1998, WRCRWA’s mission includes, “Plan, construct and operate a cost-effective regional wastewater reclamation treatment and collection system.” One of the primary goals in the recent 14 Million Gallons per Day Plant Expansion Project was to reduce operating costs, while also improving overall plant performance. WRCRWA’s design team worked closely with Southern California Edison (SCE) and their Savings by Design program to achieve this goal.

SCE’s Savings by Design program helps guide municipalities through the process of making wise energy decisions as it relates to equipment and treatment selection. SCE also provides direct cash rebates to customers who make significant reductions in overall energy consumption through implementation of efficiency improvements.

Utilizing SCE’s program, WRCRWA’s team evaluated all aspects of the WRCRWA Treatment Plant and found several opportunities to significantly reduce the WRCRWA Treatment Plant’s electrical demand. Overall, the WRCRWA Treatment Plant is expected to use approximately 9 million kWh less electricity per year. This translates into an approximately $1 million dollars, per year, energy cost savings. Because of this significant reduction in electrical demand, WRCRWA received the maximum allowable rebate of $500,000.

Notice of Completion Granted

A Notice of Completion for the WRCRWA 14 Million Gallons per Day Plant Expansion construction project has been filed with the County of Riverside for construction services.

When WRCWRA was first built, the area surrounding the property was agricultural land. Farms and ranches provided food to the neighboring communities. As residential development began to increase, more homes were built and the area looked less and less agricultural. While housing developments increased, more people moved into in the area, which intensified demand on the WRCRWA Treatment Plant.

In mid-2015, a decision was made to increase capacity of the WRCRWA Treatment Plant. Originally, the WRCRWA Treatment Plant was able to treat (clean) 8 million gallons per day (MGD), following completion of the expansion, the WRCRWA Treatment Plant is now able to treat 14 MGD.

Ratepayers benefit from this expansion, which offers increased capacity, and the ability to treat and clean more water for recycled water purposes. See Change of Use Permit update below. Reusing treated recycled water from WRCRWA can minimize the need for costly imported water.

View Notice of Completion 2018-01-24.

Change of Use Permit Creates New Source of Water for WRCRA Customers

WRCRWASchoolTour051810_0151 WRCRWASchoolTour051810_0137

A Change of Use permit, from the California State Water Quality Resources Control Board, has been granted to WRCRWA allowing Member Agencies to reuse the treated (cleaned) recycled water for approved irrigation purposes instead of discharging the water into the Santa Ana River. Following approval of the permit, changes are now underway to be able to reuse this local source of water. Currently, discharged water is sent downstream and benefits Orange County. By changing the use of the treated water, ratepayers will benefit from this local supply of water and reduce reliance on more expensive imported water.

Treated, recycled water will be available to WRCRWA Member Agencies – City of Corona, City of Norco, Jurupa Community Services District, Home Gardens Sanitary District, and Western Municipal Water District. Member Agencies can re-use the recycled water or sell it, minimizing the need for costly imported water and keeping rates as low as possible.

WRCRWA Construction Update: Anaerobic Digesters, October 17, 2017

As part of the WRCRWA plant expansion project, the remaining of the original two existing aerobic digesters have been covered and converted into anaerobic digesters. With the last digester covered and converted, there will be one less area for odor potential.  The digester is now ready for filling and will be brought online over the coming days. The filling process is anticipated to take about two weeks.

The process will begin on 10/17/17, and during this time there may be a temporary increase in odors.

We are working as quickly as possible to finish this expansion and odor-minimization project at the WRCRWA Treatment Plant. We appreciate your patience during the past two years and during this last major milestone for the project.  We anticipate major construction will be completed by the end of next month (November 2017).

If you have questions, please contact Derek Kawaii at (951) 571-7230. The WRCRWA team is sensitive to the community’s odor concerns and are committed to addressing complaints in a timely manner.

WRCRWA Construction Update: Digester Dome, July 22


Construction crews have place the dome over digester #1. We now have two sealed digesters at the WRCRWA plant. Digester #1 will go on-line in a few months. Working to reduce odors and improve infrastructure, one step at a time.







WRCRWA Construction Update: Sealing Headworks Gaps, Transition to Enclosed Solids Handling Facility, Dewatering Centrate and Optimum Chemical Dosing, July 2017

Solar DryerThe following is a list of projects currently underway to minimize odor. At the end of October, when we anticipate construction to be complete, odors are expected to be significantly minimized. During the construction and while new equipment is being introduced and made operational, odor aromas may change or even temporarily intensify.

Construction completion was pushed back until the end of October and we assure you we are working around the clock to make the necessary process improvements to address odor.

Current projects we are working on include:

What does this mean?

The headworks is an outdoor structure where initial wastewater screening occurs. Sewage is conveyed through concrete channels that have various contours and flow control gates and are mostly covered with aluminum grating. These contours and gates can cause the covers to be ill-fitting, creating gaps. Staff plans to cover those gaps and reduce the potential for odors to escape.

What does this mean?

The WRCRWA team has been working to start up and optimize a state-of-the-art “solids handling facility.” The new facility will be completely enclosed and will include enhanced odor control measures. This type of facility is the first on the west coast and is only used in a handful of wastewater treatment plants around the world.

What does this mean?

During the wastewater treatment process, sludge is separated into two forms, a liquid and a solid. The process of removing the water is called, “dewatering.” The liquid that is removed during dewatering is called the “Centrate.” The Centrate has to be treated (cleaned). Historically, Centrate was moved to a pump station that was vented to the atmosphere. To minimize odors associated with the Centrate pump station, odor minimizing measures are being constructed and includes venting the Centrate station to an odor scrubber.

What does this mean?

The wastewater treatment process naturally produces gases and odors. Contaminants are removed from gases through a process called “Scrubbing.” This scrubbing can be accomplished both chemically and biologically (depending on the constituents in the air).

The WRCRWA team is working with the manufacturers of the odor scrubbers to achieve optimum chemical dosing for the treatment of foul air through the chemical scrubber and optimizing biological population to achieve optimum odor control treatment through the biological scrubber.

Work continues toward balancing these scrubbers in order to maximize their effectiveness. 

The WRCRWA team, as well as a team of outside professionals, is working nonstop to ensure necessary changes are made to the treatment plant for maximum odor mitigation.

Through the end of October, while construction continues, odors may increase or change. If you have an odor concern, please contact the odor hotline at 951.789.5189 (Monday – Friday, 7 a.m. to 4 p.m.) during all other times, calls can be made to the 24-hour hotline.

When a call comes in to WRCRWA’s call center, the call center assistant will ask the caller for information to assist staff in their attempt to identify the source of the odor. If an odor change or increase is taking place at the time the call is received, Monday - Friday, WRCRWA staff will go to the affected area and investigate for possible causes.

Please let us know if you would like a call back, and someone will call you back within 48 hours of receiving your request.

The WRCRWA plant was originally built nearly 20 years ago when the area around the facility was comprised of dairy farms, a green composting facility, and the Santa Ana River. Because of the remote location, the plant was built outdoors as it was a more cost effective option for WRCRWA’s customers and consistent with its rural location.

After successful development in Eastvale, the dairies and composting facilities were sold and the County of Riverside rezoned the area for housing.

WRCRWA is proactively working to reduce odors. Construction projects spanning the entire plant have been in the process for several years and some are the first of their kind. Thank you for your ongoing patience with this project.

WRCRWA Construction Update: Digester Coating, April 2017 


Development to the expansion of the Western Riverside County Regional Wastewater Authority (WRCRWA) is moving forward as crews are nearing completion of phase 1, which included priority components such as odor control elements. As part of the expansion process, certain facilities at the treatment plant must undergo a coating process. The coating is necessary to protect concrete and facilities that come into contact with wastewater and chemicals used in the treatment process.

Starting on Thursday, April 13 – 19, from 2 to 10:30 p.m. coating work for Digester No. 1 will take place. As a courtesy to the nearby community, crews will work diligently to ensure that noise and light disturbances are kept to a minimum.

All previously implemented noise-reducing measures will be in place. This includes no sandblasting during nighttime hours, no back-up sirens and quiet air compressors. Temporary generators will also be strategically placed to minimize the potential for residual noise. Also, materials will be staged inside the digester prior to nighttime work. Lighting will be directed away from the surrounding neighborhoods. All of these precautions are made necessary in order to reduce disturbances to the neighboring communities.

Once completed, the upgraded plant will provide the community with permanent odor mitigation improvements. Currently, the overall completion is at about 90 percent. We are currently projecting overall completion in September 2017.

WRCRWA Construction Update: Solar Dryer System Online, March 2017 

WRCRWA Solar DryersThe WRCRWA plant expansion continues to move forward. As of Monday, the plant's new solar dryer system is officially online. This includes starting the new anaerobic digesters, the solar dryer and processes within the solids handling areas.        








WRCRWA Construction Update, January - March 2017 

IMG_7134The Western Riverside County Regional Wastewater Authority (WRCRWA) continues to make progress on the expansion of the existing wastewater treatment facility. Once the expansion is complete, the plant will have the capability to process 8 to 14 MGD (million gallons per day) of wastewater, which can be used at local parks, nurseries and other outdoor spaces while reducing our region’s dependence on imported water.

In addition, the upgraded plant will provide the community with permanent odor mitigation improvements.

During the month of January, the new SCADA system was put online. This system works with influent head works, the dewatering building, the oxidation ditch and the RAS/WAS (recycled activated sludge/waste activated sludge) pump station. SCADA stands for Supervisory Control And Data Acquisition. It is an operating system of codes that is used to control the treatment plant.

With the continued progress, the primary treatment process is preparing to go online. Primary treatment is the initial phase in the wastewater treatment (cleaning) process. It involves holding the waste in a primary clarifying basin so that the solids can separate. The solids are then removed prior to moving to the secondary phase where the biological treatment of the wastewater occurs. WRCRWA’s updates to the treatment plant make this process unique as the basins will be completely covered, which will mitigate some odors. Traditional treatment plants house the primary process in an open-air facility. The air that is contained within the covered primary clarifiers will be sent through an air scrubber to remove odors prior to release to the atmosphere.

Another major activity starting Feb. 27 is startup of the anaerobic digesters. As part of the expansion and upgrade project, the digesters are being converted to anaerobic biology. What does this mean? The digesters, when originally built in 1998, were uncovered tanks and used aerobic biology. Using aerobic biology means that the biology within the tank needed oxygen as part of its requirements to sustain itself while digesting solid materials within the tank.

With the project, these tanks have been retrofitted with covers and converted to anaerobic digesters. The biology in anaerobic digesters do not require oxygen, and as the biology digest solid material they release gas methane. The methane gas is captured and will be utilized to create heat for keeping the digester tanks at approximately 97 degrees.

 As part of the startup of the digesters, “seed sludge” will be trucked to the treatment plant from the City of Corona’s treatment plant facility. During an approximate two-week period there will be increased truck traffic going in and out of the facility to convey the seed sludge. It is anticipated that after the seeding is done, the biology will be self-sufficient and sustain itself. The entire process to reach stability of sludge in the anaerobic digesters should take approximately 45 to 60 days.

Last, the large glass structure adjacent Baron Drive is the new solar sludge dryer. We will begin using this facility very soon, which should eliminate having to use the outdoor loading structure. Once the sludge in the digesters is fully digested, it is sent through a dewatering process and dewatered.

The dewatering process will take the material from approximately 3 – 4 percent solid to approximately 20 percent solid. The 20 percent dry biosolids are then conveyed in sealed conveyors to the solar dryer where it is spread and allowed to dry to approximately 60 to 75 percent solids. While drying in the solar dryer, all air within solar dryer is treated by air scrubbers to mitigate some odors prior to release to the atmosphere. This step should mitigate odors and save money in trucking costs of biosolids as less water will be hauled off.

Updates on the advancement of the projects or construction schedule are posted on the WRCRWA Facebook page, sent via email, posted to WRCRWA.org as well as mailed to community members. To sign up for our mailing list, visit WRCRWA.org.

To report odors, please contact WRCRWA at:

  • Daytime – Monday through Friday, 7 a.m. to 4 p.m. 789.5189
  • Outside working hours and weekends (24/7) 789.5109

For more information, contact the WRCRWA Administrator at 951.571.7220

The Western Riverside County Regional Wastewater Authority Treatment Plant will be under construction through 2017. Information about the phases of construction will be posted on this page.


WRCRWA Construction Update, August - September 2016 

wrcrwa_const_201607_0021 wrcrwa_construction_201608_0024aThe Western Riverside County Regional Wastewater Authority Treatment Plant (WRCRWA) is dedicated to the completion of the plant’s expansion. WRCRWA has completed a milestone segment in the design for progress towards permanent odor mitigation improvements, which are currently being made at the WRCRWA plant.

With success, we have covered one of the two existing aerobic digesters that are currently being converted to anaerobic (covered) digesters, resulting in the assurance of reduced odors. WRCRWA will transition the remaining uncovered aerobic digester to bypass mode completely; crews will then clean the digester out, inspect the aeration equipment and prepare it for its lid. The covered digester is receiving an application of protective coatings, and welds on the lid were tested during the week of Aug. 29 – Sept. 2.

In addition, construction efforts are underway for the new cell phone tower that is being installed at the plant. Cell towers serve an important need in the community, and WRCRWA wants to inform you of the wonderful benefits of this new installation:

  • The tower will deliver a benefit to the community by providing cellular service in an area with existing dead zones. In times of emergencies having more reliable cell phone service provides added safety.
  • Financial incentives from the telecommunications tower will help keep wastewater rates as low as possible.
  • The cell phone tower may be used by WRCRWA and/or its member agencies for communications, which could improve operation efficiency and effectiveness.
  • Visually, the cellphone tower is designed to blend naturally into the surrounding area.

Updates on the advancement of the projects or construction schedule will be posted on the WRCRWA Facebook page, sent via email, posted to WRCRWA.org, as well as mailed to residents.

To report odors, please contact WRCRWA at:

  • Daytime – Monday through Friday, 7 a.m. to 4 p.m. 789.5189
  • Outside working hours and weekends (24/7) 789.5109

For more information, contact the WRCRWA Administrator at 951.571.7220


WRCRWA Cellphone Tower - July 11, 2016

A cell phone tower is being constructed at our Western Riverside County Regional Wastewater Authority Plant, located at 14634 River Road in Corona.

Design rendering (click image to view)

As one of your community partners WRCRWA wanted to inform you of this addition and share with you some of the benefits of the new cellular tower.

  • The tower will deliver a benefit to the community by providing cellular service in an area with existing dead zones. In times of emergencies having more reliable cell phone service provides added safety.
  • Financial incentives of having the cell tower help to keep wastewater rates as low as possible.
  • Visually, the cellphone tower will blend into the surrounding area.
  • The cell phone tower may be used by WRCRWA and/or its member agencies for communications, which could improve operation efficiency and effectiveness.

Questions or comments regarding the cell phone tower? Contact info@wrcrwa.org or call 951-789-5109.

WRCRWA Construction Update///Digester Cleaning Operations Scheduled - June 21, 2016

As part of the WRCRWA plant expansion project, the two existing aerobic digesters will be covered and converted into anaerobic digesters. Once the project is complete in 2017, both of the digesters will be covered.

The cleaning will begin on Thursday, June 23, 2016 and it will take approximately two weeks to clean. At the completion of each work day, the contractor is required to clean and cover all equipment (associated with cleaning activities). WRCRWA ais working as quickly as we can to finish this expansion project at the facility.

With the cleaning of the second digester, all sludge from the clarifiers will bypass the digester process and go directly to the dewatering process. It is WRCRWA's plan to operate in this bypass mode until the digesters are fully covered and functioning as anaerobic digesters.

New Odor Misting Solution in Place at Plant - May 25, 2016

In the continuing efforts to help mitigate odors at the WRCRWA facility, the facility is proceeding with a change out of the solution distributed in the misting system that is installed along the WRCRWA perimeter and on facility process components.  The new product, CupriDyne Clean, is an iodine-based solution that will be mixed with water and emitted via the misting system.  The plan is to use this material on a trial basis and see if this solution has an enhanced effectiveness over the current solution being emitted.  Research done on this shows it is entirely safe to use, and is expected to enhance odor neutralization.

WRCRWA intend to start using the CupriDyne Clean solution starting the week of June 13.  If the new product provides better results, WRCRWA will continue to utilize it.  If less effective than our current misting solution, WRCRWA will discontinue its use and reinitiate use of the current misting solution.

WRCRWA Construction Update, March 8, 2016

Construction continues at the WRCRWA plant. Beginning tonight through March 13, there will be coating of the inside of a tank, which is necessary in order to protect the tank from erosion. This work must be done at night (between 7 p.m. and 3:30 a.m.) as it needs to take place under the cooler temperatures that nighttime offers. There is no expectation of an increase in odor from this work. In addition, construction crews are committed to keeping noise levels to a minimum at night.