City makes wastewater plant pay for itself

Every municipality is looking for ways to create new non-tax revenues. Harrisburg, Pa., Mayor Stephen Reed made it a priority more than 10 years ago when he instituted the Mayor’s Energy and Revenue Development Program. As part of that program, the Harrisburg Advanced Wastewater Treatment Facility (HAWTF) became a revenue generator.

HAWTF is owned by the Harrisburg Authority and operated through a lease-back agreement with the city. It provides service to the city and six other tributary municipalities.

In 1982, Reed issued a request for proposals for a feasibility study to determine whether retrofitting the plant for cogeneration was appropriate. Brinjac, Kambic & Associates, Harrisburg, was selected to perform the analysis and determined that cogeneration capabilities could be added to the plant.

Suggested modifications included downsizing the existing UNOX pure oxygen system, since the study indicated the plant was producing oxygen in excess of that needed for operations. Payback for the downsizing investment was realized in less than one year. The study also indicated that the Harrisburg facility was operating well below its hydraulic and organic capacity. Harrisburg took advantage of the excess capacity by accepting outside sludge. As a result, the facility established its Contract Hauling Waste Program (CWHP), benefits of which included:

* additional revenue through permits, disposal and lab fees, as well as through better use of plant capacity and the generation of electricity for resale; and

* the provision of an environmentally safe waste disposal alternative.

Interestingly, while the program resulted in a substantial increase in process waste and septage, it did not create the need for additional employees or infrastructure.

In 1994, HAWTF treated almost 21 million gallons of process waste and septage, creating revenues of $877,145. The resale of electricity from its cogeneration capabilities resulted in additional revenue of $113,616. HAWTF estimates the combined cogeneration and CHWP revenues will exceed $1 million annually over the next several years.