The City of Rome needed to increase the capacity of the Blacks Bluff WWTP so they had JJ&G Engineers look at the existing equipment to see what could easily be expanded and incorporated in the expansion.


The existing plant used the Schreiber counter current aeration process for biological treatment of the waste water.  Schreiber proposed the addition of fixed air diffusers on the perimeter of the existing aeration basins in order to meet the additional oxygen demand for the plant expansion.  This allowed the existing bridge, diffusers and concrete tanks to be used in order to keep the cost of construction to a minimum.  The proposal was determined to be the best solution and was installed.

In order to install the additional diffusers in the aeration basin, an isolation gate had to be installed in the tank.  Fontaine was asked to come up with a solution that would fit in the round tank and have a gate operator design that would allow the aeration basin bridge to rotate without impeding the travel.  The size of the gate required a dual stem configuration.  Of the gate manufacturers approached with this particular application, only Fontaine was able to offer a fabricated stainless steel solution.

The City of Rome needed a grit and grease removal system at the head of the plant to remove the heavy grit and grease loads that come to the plant.  The Schreiber design was selected for this application.  The design had to take into account that the screens upstream of the grit and grease tanks had 2” bar spacing and the type of grease coming to the grit and grease removal system would be a heavy grease intermingled with whatever solids passed through the screens 2” bar spacing.  Schreiber modified the design to incorporate air and water lances that would push the heavy grease down the grease channel to the removal auger.  The City, JJ&G and Schreiber worked to fine tune the design after installation so that the grit and grease removal system could remove the wastes that were particular to this application.  

The solids handling at the plant incorporates the use of anaerobic digesters.  The existing digesters were rehabbed and Vaughan’s Rotamix digester mixing system was installed to provide an efficient mixing system for the plant upgrades.


Gorman-Rupp self priming pumps were selected for the Waste Sludge Pump application.


The Blacks Bluff WWTP was designed to have a high flow by-pass that sent flow to side stream tanks for treating the screened and diluted wet weather peak flows.  The flow eventually makes it to the chlorine contact chamber where it is disinfected by chlorine that is fed by Severn Trent Capital Controls gas feed equipment.  The gas is inducted into the chlorine contact chamber with Chlor-A-Vac gas induction units.  The design also incorporates the use of Halogen Emergency Shut-Off valves on the chlorine gas cylinders that will turn off the flow of gas in an emergency situation.