The JEA District II Water Reclamation Facility (WRF) discharges up to 4.0 mgd of highly treated wastewater to the St. Johns River through a single outfall at times when reuse is not feasible. In the winter, this discharge to the river may result in a warm water attractant for manatees. ATM developed and analyzed various outfall modifications that would result in the elimination of this potential warm water manatee attractant.
The evaluation was completed using an EFDC hydrodynamic model to extract current and vertical density profiles. Nearfield thermal mixing analyses were conducted with CORMIX. ATM’s analyses led to design and permitting of a physical barrier to exclude manatees from the outfall area and minimize its potential as an attractant during cold weather.