Struvite Is History

A view of the new Phosphorous Recovery Facility at the Robert W. Hite Treatment Facility (RWHTF) in Denver. The reactor is a tall, gray cylinder and is one of the more prominent structures at the plant site.
Above: Jerod Swanson-Centrisys/CNP and Isaac Avila-Metro Water Recovery beneath the MagPrex phosphorus recovery reactor.
Top banner: Struvite in powdered form is produced by our MagPrex phosphorus recovery reactor and transferred to A1 Organics for a phosphorus-rich composting product.

Thursday, August 26, 2021, was a day for the Metro Water Recovery history books as we transferred our first load of phosphorus-rich struvite to A1 Organics, a local composting company. This load of struvite totaled around 23 tons of magnesium ammonium phosphate recovered directly from the treatment process at the Robert W. Hite Treatment Facility (RWHTF) downstream of Denver. 

Major Achievement

Sending struvite to A1 Organics achieves a milestone and major goal of our Phosphorus Initiative – to recover phosphorus from the water we treat and beneficially reuse this element. Recovering the phosphorus meets environmental regulations and prevents it from (1) passing through our treatment and into the South Platte River and (2) forming rock-hard struvite inside our process equipment. 


Hard work and dedication from our teams and partners propelled the organization to reach this milestone. Our Technology and Innovation, Comprehensive Planning, Engineering, and Operations departments led efforts to select, construct, and start up a new 421,000-gallon Centrysis/CNP MagPrex™ phosphorus recovery reactor in the middle of the RWHTF. Our Resource Recovery and Reuse department is leading the handling and distribution of the struvite product to A1 Organics. 

Happy Ending  

Operation of the MagPrex™ reactor, along with biological phosphorus removal technologies, has reduced phosphorus in the water we treat and return to the South Platte River to less than 0.5 milligram per liter. Since starting up the reactor in October 2020, our pipes, pumps, and other equipment have stayed struvite-free.  

Want to know more? 

Click here to watch a video about our phosphorus recovery efforts (please note we’ve recently changed our name).  

Click here to view our Phosphorus Initiative infographic