Q. What is recycled water?
A. The California Water Code defines recycled water as “water which, as a result of treatment of waste, is suitable for a direct beneficial use or a controlled use that would not otherwise occur.” Water from tubs, toilets and sinks inside homes and offices travels to the Laguna Treatment Plant, where it is cleaned through a treatment process that is ranked among the top five percent in the world for wastewater treatment technology. The result is recycled water – a high-quality, tertiary-treated water that is safe for the irrigation of landscapes, agricultural crops, vegetable crops that are eaten raw, vineyards, playgrounds, golf courses, parks, cemeteries, freeway embankments, and street medians. It is also frequently used in industrial processes, decorative fountains, fire suppression systems and much more.
Water recycling allows water managers to match water quality to specific reuse applications. This reduces the amount of fresh water required for non drinking uses, ensuring that the best and purest sources of water will be reserved for the highest use - public drinking water.

Q. Where does recycled water come from?
A. The Santa Rosa Subregional Water Reuse System receives and treats wastewater from more than 225,000 residents and 6,500 businesses in the cities of Cotati, Rohnert Park, Santa Rosa, Sebastopol, the South Park Sanitation District, and portions of unincorporated Sonoma County. After entering the Laguna Treatment Plant, wastewater from homes and businesses undergoes a carefully regulated purification and disinfection process, known as tertiary treatment. Throughout the process, samples are taken and tested in a state-of-the-art laboratory to ensure high-quality water.
Q. What kind of water will the Laguna Treatment Plant produce?
A. Santa Rosa treats its wastewater to tertiary recycled water standards (also referred to as advanced water treatment) which is the highest level of treatment defined by the State of California (Referred to as Title 22); this level of treatment allows for unrestricted reuse in virtually all recycled water applications. To ensure a consistent level of quality, which meets or exceeds its intended uses, the City’s recycled water is monitored and tested daily.
Q. Is Recycled Water Safe?
A. Yes, recycled water is safe. To ensure a consistent level of safety, recycled water is continually regulated, monitored and tested by the Laguna Environmental Laboratory, the Environmental Protection Agency, the Regional Water Quality Control Board, and the Department of Public Health. This ensures water quality that far exceeds its intended use. In thousands of applications throughout the U.S., there has never been a documented illness from recycled water use. Consistent inspections and strict regulations are also in place to ensure that the drinking and recycled water systems remain separate. Nature has recycled water for millions of years. By duplicating much of nature’s process, it is now possible for us to purify water to a level that is beyond our drinking water standards.
The safety of recycled water is explored in-depth in "Recycled Water: Putting the Risk into Perspective," a project funded by the WateReuse Research Foundation. The research team analyzed and explored the potential exposure risk pharmaceuticals and personal care products in every day life compared to exposure from using recycled water for approved purposes, such as landscape and agricultual irrigation. The project researchers explored four common scenarios of exposure - click on a link below to read the results:
A child at Play The Golfer Landscaper Ag Worker
Q. How is recycled water made?
A. There are four treatment steps that wastewatergoes through before it is considered tertiary recycled water: primary treatment, biological treatment (secondary), filtration and disinfection (tertiary). These steps are necessary before Santa Rosa’s recycled water is used for agricultural or landscape irrigation, delivered to the Geyser’s Project, or released into the Russian River.
Q. Where is Santa Rosa Subregional Reuse System’s recycled water currently used?
A. Santa Rosa uses approximately 98 percent of its tertiary-treated water to irrigate approximately 6,400 acres of farmlands, vineyards, and public urban landscaping, such as A Place to Play, Finely Park and the Oakmont Golf Course, and for the Geysers Recharge Project, which pumps millions of gallons per day of tertiary-treated recycled water along 41 miles of pipeline to the Geysers steam fields where it is used to generate electricity.
Q. With an expanded reuse program, how else will recycled water be used?
A. Under the proposed project, the recycled water will be used in various parts of our city, bringing this vital resource to select commercial, industrial, institutional and common area residential landscapes. A series of potential irrigation sites are currently under consideration.
Q. Where else is recycled water used?
A. Water recycling is long past the experimental stage in this country and throughout the world. It is being used for crop irrigation as well as in parks, school playing fields and other open spaces in many states including Arizona, Texas, Florida and California. Some California communities have relied on recycled water for more than 20 years for landscape irrigation at schools, parks, median strips, large landscape areas, and golf courses. Recycled water also is used in office parks, indoor fire protection and toilet flushing in commercial buildings, fountains, and car washes. In addition to Santa Rosa’s current water recycling programs, recycled water is used in other California communities like Windsor, Rohnert Park, Petaluma, San Jose, Redwood City, Sunnyvale, Orange County, Los Angeles County, Santa Clara County and San Diego County.
Q. Why is water recycling important?
A. For every gallon of recycled water used to irrigate public places, such as Finley Park, a gallon of precious drinkable water is saved. Other benefits of using recycled water for irrigation include a drought-proof water supply, less need to release recycled water into local waterways, the development of a new water supply with a locally controlled, reliable source that is environmentally responsible—it is the same concept that drives the recycling of bottles, cans and paper.
Q. Will the recycled water be safe for children playing in parks?
A. Yes, over 1,600 sites in 22 states are irrigated with recycled water. The water is treated to a quality that can be used to supply a recreational lake used for boating and swimming. The California Department of Public Health has determined that the water is essentially “pathogen free.” In other words this water is carefully monitored and cleaner and safer than water at most beaches.
Q. Is recycled water safe to drink?
A. Santa Rosa’s Urban Reuse Project is for landscape irrigation and potential industrial uses only. However, indirect drinking-water reuse occurs in some communities as recycled water from an upstream community rejoins a river and becomes part of a downstream water supply. In addition, milestone groundwater recharge projects in Southern California have an excellent track record of success, with over 30 years of history and no outbreaks of waterborne disease linked to recycled water. Through groundwater recharge, recycled water percolates into groundwater basins, mixes with naturally-occurring groundwater, and eventually is pumped out for drinking-water use. Treatment technologies are constantly improving, and indirect potable reuse is likely to become a well accepted part of future water supply planning.
Q. Who develops the health standards for recycled water?
A. The California Department of Public Health (DPH) establishes and enforces the standards for recycled water. Both the City of Santa Rosa and the customers using the water for irrigation must meet State requirements for recycled water. In addition, the California Regional Water Quality Control Boards issues water recycling permits based on the established DPH regulations.
Q. Is the use of recycled water mandatory?
A. For all existing sites included in the project area, recycled water use will be voluntary. For any new development that will use water for irrigation in the project area, recycled water use will be mandatory.
Q. Could recycled water get mixed with Santa Rosa’s drinking water?
A. Pursuant to state law, the City will lay a separate set of purple colored pipes to carry the recycled water. There will be no direct interconnections or cross connections between the two water systems. These systems will be regularly monitored to ensure safety.
Q. How will I know if the water I see irrigating parks and other outdoor spaces is drinking water or recycled water? 
A. Landscape areas using recycled water will be clearly marked with signage clearly stating the use of recycled water.
Q. What kind of technical support can recycled water customers expect?
A. The Santa Rosa Urban Reuse Project will provide an extensive program of support services information as well as direct assistance to recycled water customers.
Assistance provided will include:
- Site evaluations
- Water quality information
- Irrigation system evaluations and recommendations to improve water use efficiency
- Training for site supervisors
- Information about successful landscape management
- Information on rebates and incentive programs for irrigation equipment upgrades
Q. Does recycled water give our landscape sufficient nutrients?
A. Recycled water can play a major role in the successful management of landscapes in our area. The higher nutrient content of nitrogen, phosphorous and potassium in recycled water is beneficial to landscapes. In many cases, turf and other landscape plants will be able to obtain from recycled water all the phosphorous and potassium they require, and a large part of their nitrogen requirement. Sufficient micro-nutrients are also supplied by recycled water.
If you have additional questions or need more information, please call us at 707-543-4200.