Doctors Lake Enhanced Phosphorus Removal

Clay County, Florida

Phosphorous Elimination


Owner: Clay County Utility Authority

Engineer: OECS, LLC and Green Earth Operations

Installation: July, 2019

Technical Description:

  • PES Media

  • PES Distribution System

To attain a 6,500 pound annual phosphorus reductions, SWIG will install the Phosphorus Elimination System (PES). The PES is a vegetated vertical filtration system which utilizes an engineered media formulated for extremely high phosphorus loads from the Flemings Island wastewater treatment plant. Each day, 2.4 million gallons of treated wastewater with high phosphorus concentrations are pumped onto the 40,000 sq. ft. facility. To treat ten times the load of an ABS system, the PES media has been especially formulated to effectively remove these extreme P loads. The PES system provides effective P removal approaching 90% for its design life of six years.

The spent media containing very high amounts of P is then used as soil amendment. This amendment provides all the P needed for plants, all the while not leaching out any P. In this way, the system not only removes a substantial proportion of the Doctors Lake P loads during operation, its media will eventually reduce similar loads from golf courses and other fertilized landscapes. As a result, the PES is the most cost-effective and sustainable approach to reduce P loads available.