Frequently Asked Questions

1. What is the Advanced Purified Water Facility at American Flat?

A 1-2 million gallons per day groundwater recharge project to evaluate and determine if the State of Nevada’s Category A+ reclaimed water quality (advanced purified water) offers regional long-range water supply benefits. Advanced purified water will be stored in the aquifer and initially be extracted and utilized for irrigation of the American Flat site, and later potentially used to augment drinking water supplies. The project includes upgraded treatment facilities at the Reno-Stead Water Reclamation Facility (RSWRF), an advanced purified water treatment facility to be built near the RSWRF site, conveyance pipelines, pump station improvements, and injection and extraction wells.

2. Why is OneWater Nevada doing this Project and how does this benefit the region?

In light of the challenges and increasing concerns with over-use of water coupled with climate uncertainty (such as longer growing season, snowpack changes, and water runoff timing), it is becoming more and more important to provide a local, reliable, drought-proof water source for both the near- and long-term health and economic vitality of our region. This project would reduce reliance on the Truckee River water supply and enhance the region’s overall water supply resiliency.

3. What is Advanced Purified Water?

Advanced purified water refers to highly treated recycled wastewater that has been processed using proven, state-of-the-art water purification technologies. The resulting pure water meets state and federal drinking water standards.

4. What are the treatment steps to produce Category A+ advanced purified water?

There are currently nine key steps in the treatment train for producing Category A+ advanced purified water, including the primary treatment of wastewater. Alternate steps are being tested and evaluated for consideration to optimize the final treatment train design.

1. Coagulation

Safe, chemical coagulants are added to water causing particles to stick together and form larger impurities which are more easily removed by subsequent treatment steps.

2. Flocculation

Particles floc (group) into larger particles which settle to the bottom of the tank. Water flows up through angled tubes, which also promote settling of particles.

3. Clarification

A buoyant adsorption media bed further reduces solids. Particles adsorb (stick) to the media as cleaner water flows up through it.

4. Filtration

Mixed media filtration removes solids and 99.9% of pathogens.

The above four steps create recycled water suitable for irrigating parks, golf courses, and crops, and for industrial purposes. Then, that recycle water is processed through four additional steps to achieve the Category A+ level of purification.

6. Ozonation

Ozone is a powerful oxidant used to break down organic constituents into smaller, more readily biodegradable molecules. Because of its short life, ozone is generated on-site. Oxygen atoms and molecules are bonded using an electric field to create ozone.

7. Biologically Active Filtration

Microbiologic organisms and carbon adsorption aid in the biodegradation and removal of dissolved organic constituents.

8. Granular Activated Carbon

This is a polishing step for further removal of trace amounts of dissolved organic constituents, such as pharmaceuticals or disinfection byproducts.

9. Ultraviolet Disinfection

High-intensity ultraviolet light inactivates (kills) pathogens or viruses.

After the final step, the Category A+ water (which meets drinking water standards) is injected into the groundwater aquifer, where further natural treatment occurs before extraction. This water is now clean enough to be used for irrigation, aquifer recharge and recovery, and is approved for human consumption.

5.  Is the technology proven and safe?

Yes. The technologies behind these water purification steps have been repeatedly tested and proven to be effective at producing water which meets or exceeds all state and federal drinking water standards. After decades of using purified water to recharge underground and surface water supplies in other parts of the US and the world, there have been no adverse health effects from its use.

6. Does the advanced water purification process remove pharmaceuticals and personal care products?

Existing water and wastewater treatment processes significantly reduce the levels of such substances and to date state and federal regulatory authorities have not found cause to require further reductions although monitoring and research is ongoing and updates are made when deemed necessary. Advanced water treatment processes remove contaminants to levels below concentrations of significance and can produce water qualities that are equal to or better than existing drinking water sources.

7. Is Category A+ advanced purified water (advanced purified water) safe, and does it meet drinking water standards?

Yes. It is regulated to the same rigorous state and federal standards required for all drinking water. In 2016, the National Water Research Institute (NWRI) commissioned a third-party, technical panel of water experts to evaluate and review the Project. This expert panel concluded that it was “plausible, feasible and protective of public health.” Water quality sampling confirms purified water that undergoes this level of treatment has a much higher level of water quality than treated groundwater or surface water. A follow-up review by a NWRI panel of experts will be conducted starting in fall, 2022.

The State of Nevada, which regulates the treatment of groundwater and surface water, is also responsible for regulating the production of purified water. Regulations ensure water purveyors meet state and federal water quality standards, making certain the water is safe. This also includes testing and strict water quality requirements for removing constituents of emerging concern such as pharmaceuticals and personal care products.

8. What do the terms Indirect Potable Reuse and Direct Potable Reuse mean?

How potable reused water is delivered determines if it is called indirect potable reuse or direct potable reuse. Indirect potable reuse means the water is delivered indirectly. After it is purified, the reused water is blended with other supplies and/or sits for a period of time in storage – for example in a groundwater basin, or a constructed or natural reservoir. This blended water then gets delivered to a pipeline that leads to a drinking water plant or distribution system.

Direct potable reuse means the purified water is put directly into pipelines that go to a drinking water plant or distribution system. Direct potable reuse may occur with or without “engineered storage” such as underground or above-ground tanks.

9. Where is water purification already in use?

Using purified water for drinking is not new in the U.S. and has been in use for more than 40 years, since the 1970s. Many communities such as Monterey, San Diego, Pismo Beach, and Santa Clara in California, as well as Singapore, Australia, Texas, Virginia, and Colorado, are currently operating or evaluating this type of project – with many more in various stages of consideration or development. California’s Orange County Water District’s Groundwater Replenishment Project has produced over 200 billion gallons of purified water to recharge its groundwater basin. Disneyland theme park proudly promotes its participation in this type of water recycling and purification program, boasting that, “…almost all the water used at the Resort is recycled in this manner.”

Where is water purification already in use?
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10. What is groundwater recharge?

Groundwater recharge (also referred to as replenishment) is an innovative concept in water conservation/reuse where recycled water is treated to drinking water standards and recharged into a groundwater basin, for later extraction and use.

11. Isn’t all water recycled?

Yes, all water is naturally recycled and reused as part of the hydrologic cycle, through evaporation, condensation, and precipitation. Human-made water recycling, also known as water reclamation or water reuse, centers on using wastewater from homes and businesses that is treated enough to be reused safely.