The City of Durham, N.C. is currently pilot testing an algal scrubber device that will grow algae over a period of time and removing nutrients from the source water. The pilot equipment is set up on Falls Lake, water from the lake is pumped into the unit, the algae in turn use the nutrients (nitrogen and phosphorous) to continously grow the algal mat. At a predetermined point the algal mat is harvested and removed from the system. You may view a video of the pilot unit at: https://www.youtube.com/watch?v=-0WsLRdnk3M .