Resource Recovery

The Clean Water Institute aids with the deployment and improvement of nutrient recovery technology marketed and sold in partnership with Ostara Nutrient Recovery Technologies Inc. The Clean Water Institute can pair WASSTRIP with the Ostara reactor, turning polluting nutrients into a safe and usable commercial fertilizer, marketable to nurseries, golf courses and certain agricultural markets. The fertilizer, Crystal Green®, is a premium, slow-release, energy-efficient and environmentally friendly product. Watch the video below to learn about our phosphorus recovery journey and how we can help other municipalities on the path to resource recovery.  


Clean Water Services developed a process called WASSTRIP (Waste Activated Sludge Stripping to Remove Internal Phosphorous) that reduces struvite (magnesium ammonium phosphate) buildup in the operation of anaerobic nutrient removal facilities. Biological phosphorus removal facilities need to recycle nutrient-rich sludge several times within the wastewater facility, which adds to the operating costs and takes up plant capacity. Phosphorus, ammonia, and magnesium become highly concentrated when this happens. Struvite formation coats pipes, valves, and other equipment which reduces flow capacities and increases maintenance requirements.

WASSTRIP technology can save wastewater treatment plants hundreds of thousands of dollars a year in maintenance and longer facility lives. In preventing struvite buildup, WASSTRIP also:

  • Provides a raw source of nutrients that can be turned into fertilizer
  • Reduces chemical use
  • Increases wastewater treatment facility reliability and capacity
  • Reduces operations and maintenance costs (this system prevents plant downtime and maintenance costs of cleaning clogged pipes, pumps and other equipment, and reduces sludge volumes and disposal costs)
  • Reduces greenhouse gas emissions through reduced energy usage
  • Dewaters solids
Clean Water Grow®

The Clean Water Institute sells a retail fertilizer blend, partially composed of Crystal Green®, called Clean Water Grow®. Clean Water Grow® All-Purpose Plant Food is perfectly formulated for flowers, shrubs, fruits and vegetables. The slow-release formula of phosphorus, nitrogen, and potassium provides a steady supply of vital plant nutrients for up to six months. This unique slow-release blend helps to reduce fertilizer leaching and protect local waterways by gently releasing the needed nutrients as the plants use them. 

Scroll through our 2021 Annual Report to explore our Year in Review.

Year in Review

Receive news on what we are doing in the community and our innovative solutions to continue on providing clean water.