Compliance Strategies for Your CSO Long Term Control Program: A Case Study of the Citizens Energy Group (Indianapolis, IN) Approach

In 2011 Citizens Energy Group (Citizens) purchased the water and wastewater systems from the City of Indianapolis, and assumed responsibility for implementation of a Combined Sewer Overflow (CSO) Long Term Control Plan (LTCP). Citizens is currently in the process of implementing the LTCP in accordance with the requirements of a federal Consent Decree. Citizens’ foremost focus at this time is completion of implementation of the Plan as scheduled and budgeted. The plan is scheduled to be completed in 2025.Citizens also has been re-examining the various strategies that are available to CSO communities to demonstrate compliance with state and federal requirements as related to the residual CSO discharges that are anticipated to occur after full implementation of the LTCP. Citizens finds this review essential in the responsibility to ratepayers supporting the approximately $1.9 billion investment being made to implement the LTCP.This paper will address the various strategies that are available to CSO communities to demonstrate compliance with the various state and federal requirements affecting the residual CSO discharges that most CSO communities will continue to experience after implementation of their CSO control programs. Strategies for compliance discussed in this paper include demonstration of compliance with in-stream water quality standards (WQS), WQS variances, revised or updated Total Maximum Daily Load (TMDL) allocations, and designated use modification via Use Attainability Analysis (UAA).The paper also provides a case study of the regulatory compliance strategy that Citizens is evaluating. This discussion includes Citizens evaluation of specific strategies including development of a UAA and demonstration of compliance with WQS.