Wastewater Optimization

Municipalities throughout North America have substantial investments in their wastewater treatment systems, and of course as populations grow, utilities must consider investing in expansion. Recently, a sometimes overlooked protocol of optimization, the Composite Correction Program (CCP), has gained resurgence as a technique to ensure existing infrastructure is utilized to the best of its capacity.

In 1996, the Ontario Ministry of Environment and Energy, with matching support from the Government of Canada, funded The Ontario Composite Correction Program Manual for Optimization of Sewage Treatment Plants. The manual, adapted from a handbook published by the United States Environmental Protection Agency in 1989, describes how to apply the Composite Correction Program to economically improve the performance of existing municipal sewage treatment plants in Ontario.

The CCP, as developed by the U.S. EPA, is a two-step process. The first step is a Comprehensive Performance Evaluation (CPE) of the facility that examines four areas—operations, design, administration, and maintenance—to identify performance-limiting factors that prevent the facility from achieving good economic performance. At this point, the potential to improve performance of the facility is reviewed and the plant is either deemed “capable” or “not capable.” If the facility is capable, then the second step is to address these limiting factors through a Comprehensive Technical Assistance (CTA) program. If the plant is deemed not capable, then the next step is to go to a process audit or design upgrade.

A Comprehensive Technical Assistance program involves systematically addressing the performance-limiting factors identified in the CPE that do not involve capital works. A major component of the CTA is hands-on operator training and support to implement process control techniques and standard operating procedures (SOPs) to improve process performance. In addition, empowering operating staff with enhanced skills in priority setting and problem solving fosters an ideal environment to improve performance.

Not every plant proceeds to a CTA, and that is not bad news either. George Terry, a senior process advisor, and his team of process specialists from the Ontario Clean Water Agency (OCWA) have experience with CPEs that validate that the facility is delivering satisfactory performance and capacity.  In these circumstances, a CTA is not needed, but Terry said that “reports from the CPE assist the utility as backup in applying for funding to support their long-term capital plans for sustainability.”

In 2012, the Ontario Ministry of Environment’s Showcasing Water Innovation program provided an opportunity to continue to develop a watershed-wide wastewater optimization program to demonstrate improved performance at wastewater treatment plants in the Grand River watershed. 
(bit.ly/grandriveropt)

The program also aimed to demonstrate good asset management to effectively tap the full potential of existing wastewater infrastructure and defer costly upgrades. Leveraging the principles of CCP, participating municipalities demonstrated latent capacity, higher effluent quality, and a deferral of infrastructure capital costs. For example, Haldimand County deferred more than $10 million in capital infrastructure costs.

Optimization is a continuous process which invests in skills development, as well as the improvement of operators and managers to manage wastewater treatment processes more effectively. The goal of the optimization program is to achieve high quality wastewater effluent, economically, with existing infrastructure. The watershed-wide program is intended to give wastewater managers and operators at all of the wastewater treatment plants in the watershed the tools and approaches to improve effluent quality. Improved process control means improved effluent quality which, in turn, improves the health of the rivers in the Grand River watershed.

Using the Composite Correction Program is a fundamental part of optimizing total life-cycle costs in delivering wastewater services. It supports long-term thinking that stretches infrastructure spending, reduces operational costs, and improves product quality. “That’s the real benefit of the CCP approach,” Terry said. “It gives stakeholders the assurance that they are getting full value from their existing infrastructure, before laying out big dollars in capital expansions.”  WC

Nick Reid is executive director of strategic partnerships for OCWA. This article appears in Water Canada’s January/February 2015 issue.