Clearing the Fog: Developing a FOG Program and Fee in San Antonio

As regulatory limits on wastewater effluent become stricter, the cost to treat wastewater to these stricter standards increases. Many utilities are assessing specific charges to those customers who contribute high-strength wastewater into the collection system. Surcharges for high biochemical oxygen demand (BOD) and total suspended solids (TSS) are common throughout the industry. However, some utilities, particularly in the western United States, are assessing charges for other characteristics of contributed wastewater, including phosphorous content, Total Kjeldahl Nitrogen (TKN), and fats, oils and grease (FOG). Of the ten largest providers of retail wastewater treatment services in Texas, San Antonio Water System (SAWS) has the most comprehensive program for sampling and charging high-strength customers. Currently, SAWS assesses BOD and TSS surcharges to 14 high-strength customer classes, not including Significant Industrial Users (SIU). Now SAWS has engaged Red Oak Consulting (Red Oak) to assist in the development of a FOG program and fee to encourage its customers to continue improving the quality of wastewater discharged into the wastewater system.As part of the FOG Program study, Red Oak researched wastewater utilities throughout the United States to identify other FOG programs and fees. There was significant variation in the programs identified, and SAWS staff selected several elements of these programs to include in its program. In addition, SAWS and Red Oak modified some elements of these programs to make them a better fit for SAWS' objectives. Elements of FOG programs for consideration include:• Frequency of inspection• Method of inspection• Record-keeping requirements• Fee structure• Penalty for violation or non-compliance.The objective of the program is to incentivize customers to reduce the amount of FOG they contribute to the collection system. By reducing FOG at the source, SAWS can avoid costly cleaning and maintenance and reduce or eliminate sanitary sewer overflow (SSO) occurrences. In fact, the additional cost of the program is likely to be offset by these cost savings and the improved quality of influent to the wastewater treatment plants.This presentation will introduce SAWS' FOG program and fee structure and outline the development process. We will review the key issues and decisions, identify the alternatives that were considered, and explain the basis for selecting the program elements and fee structure. Finally, we will provide an update on the program and discuss any challenges that were faced during implementation.