FAQs re: Recycled Water

Recycled Water irrigation sign

What is Recycled Water?

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 City of Santa Rosa’s 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.

Where does the City’s Recycled Water come from?

The City receives recycled water via the Santa Rosa Subregional Water Reuse System (Subregional System) Laguna Treatment Plant.  The Subregional 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.


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.

Is Recycled Water Safe?

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 California Department of Public Health (DPH) establishes and enforces the standards for recycled water. Both the City 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.

Where is Recycled Water used in the City?

The City has been using recycled water throughout the City on approximately 580 acres of urban landscaping including City parks, schools, SSU, commercial properties and Foxtail Golf Course since 1998.  In 2014, the city saved over 270 million gallons of potable water by using recycled water for irrigation.

Is it safe for Parks and Schools?

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.

Is Recycled Water safe to drink?

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.

Why should we use Recycled Water?

Recycled water offers a drought resistant water source that is dependable, locally-controlled, and generally beneficial to the environment. Recycled water allows communities to become less dependent on groundwater and surface water sources and can decrease the diversion of water from sensitive ecosystems. Additionally, recycled water may reduce the nutrient loads from wastewater discharges into waterways, thereby reducing and preventing pollution.

What is the difference between Recycled Water and Reclaimed Water?

These terms are generally used interchangeably and which word is used depends on the region. Recycled or reclaimed water is water that is used more than one time before it passes back into the natural water cycle. Thus, water recycling is the reuse of treated water for beneficial purposes such as agricultural and landscape irrigation, industrial processes, toilet flushing, or replenishing a groundwater basin (referred to as groundwater recharge).

Does Recycled/Reclaimed Water need to be kept separate from other water?

Nonpotable recycled water goes through a separate pipeline system to the customers. It is completely separate from the drinking water pipeline system. Periodic cross connection tests ensure that the nonpotable recycled water pipelines are not accidentally connected to the drinking water system. In addition, there is ongoing monitoring and testing of the nonpotable recycled water and drinking water systems to protect the public's health.

Does Recycled Water give our landscape sufficient nutrients?

Recycled water can play a major role in the management of landscapes in the City. 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.