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Recycled water is wastewater that has been purified through a high level of treatment.  This processed water is treated to strict standards set by the California Department of Health Services and is constantly monitored by local, state, and federal regulatory agencies to ensure it continuously meets those standards. 

Recycled water has been found safe for irrigation, industrial and agricultural uses.  In fact, all water on Earth is in some way recycled.  Mother Nature has been recycling water and wastewater for millions of years through a natural cleansing process of sedimentation, organic consumption, natural filtration and disinfection. Modern wastewater treatment technology essentially speeds up this natural process.

Yes.

Recycled water is wastewater that has been purified through a high level of treatment.  This processed water is treated to strict standards set by the California Department of Health Services and is constantly monitored by local, state, and federal regulatory agencies to ensure it continuously meets those standards. 

Recycled water has been found safe for irrigation, industrial and agricultural uses.  In fact, all water on Earth is in some way recycled.  Mother Nature has been recycling water and wastewater for millions of years through a natural cleansing process of sedimentation, organic consumption, natural filtration and disinfection. Modern wastewater treatment technology essentially speeds up this natural process.

Yes, The California Department of Health Services has very high treatment standards for recycled water.  Palo Alto’s recycled water meets or exceeds all state standards for water used for irrigation and other uses with similar public exposure.  Ponding of recycled water on grass or other areas is specifically prohibited as added insurance that a significant amount could not be ingested by children.  In addition, according to Dr. Stanley Deresinski, Clinical Professor, Stanford School of Medicine, one would have to drink at least 12 gallons of reclaimed water, in a single sitting, in order to ingest an infectious dose of coliform bacteria.

While small concentrations of pollutants are found in recycled water, there is no exposure route for these compounds to be ingested by humans when using recycled water for landscape and industrial purposes. Program staff monitor research regarding treatment technologies, mechanisms of human exposure, and health risk assessments to ensure that reuse practices protect human health.

Palo Alto Regional Water Quality Control Plant’s “tertiary” recycled water has been used on almost all plants and grasses successfully for many years. However, with TDS levels between 800-900ppm, it is a bit saltier than the drinking water supply. It is not recommended for redwood trees or other salt sensitive plants in large quantities. If your property has a lot of salt sensitive plants and you’re concerned with water quality, you may prefer to have reclaimed groundwater delivered instead.

The Purple Pipe Company also procures groundwater from basement de-watering sites in Palo Alto. The groundwater generally has a lower salt content, but it is not filtered or purified. The groundwater is tested once when the basement de-watering commences. Chemical analysis differs a bit at each basement site and, although it is very clear, it may contain suspended solids (extra service fees may apply). Groundwater salinity tests are done by measuring the electrolyte composition of the water by examining its specific electrical conductance (SEC). This measures microsiemens content along with pH balance, alkalinity, and Eh (redox potential). Specific conductance is the measure of the ability of a water conduct electricity. In general, the higher the concentration of dissolved sales in the water, the easier it is for electricity to pass through water. Conductivity is reported in micromhos (umhos) of microSiemens (uS) per centimeter (cm). Conductivity measurements can be converted to TDS measurements, which are usually reported in parts per million (ppm) by roughly multiplying your umhos/cm or uS/cm by a conversion ratio of 0.66, although this can ratio can range from 0.50 – 0.80 depending on the quality of the source. When converted to TDS levels, the groundwater we use from Palo Alto typically converts to TDS levels in the 400-650 ppm range.