If you asked the members of Caryville-Jacksboro Utility Commission in Tennessee about sustainability 13 years ago they would have called it unattainable. In 2000, the utility faced a $13 million overhaul to fix a failing collection system infrastructure. Years of deterioration, inflow and infiltration (I and I) were challenging treatment plant capacity, equipment life and creating $18,000 in annual energy cost overruns.
A Mission RTU monitoring a CJUC lift station.
The utility spent 48 man hours per day repairing and overseeing 45 remote pump stations. There were not enough resources to accommodate the community or future generations. CJUC executive secretary Frank Wallace called these short-term solutions burdensome.
The utility had to find a more cost effective way to reduce I and I operations and oversight. Wallace researched every solution to meet the community's short and long-term needs. In 2000, he met with the Environmental Protection Agency (EPA) to discuss energy conservation and I and I reduction. He agreed to launch a system-wide evaluation to identify collection system problems. Wallace implemented a Capacity Management, Operations and Maintenance (CMOM) program. CJUC lacked a Supervisory Control and Data Aquisition (SCADA) system that could gather data in as part of the CMOM program. After evaluating options, Wallace sent a request to the directors of Caryville and Jacksboro to authorize a managed SCADA system from Mission Communications. He installed Mission's remote terminal units (RTUs) on the utility's most critical pump stations.
The Mission system proved its worth in several months. Personnel now spend 30 minutes per day reviewing site operations. They are kept apprised of pump station anomalies through real-time alarms generated by the new system. These notifications allow personnel to focus on preventive maintenance and other pressing issues. Cellular-to-Web data transmissions save employees time by giving them information that can be accessed from their Web-enabled devices. Reports and trending data created by the Mission system also help them identify pump I and I issues. The runtime variance report is emailed to Wallace if runtimes exceed the average.
"We know if we're having an I and I issue during a storm event because we have more runtimes and more starts," explained Wallace. "Not only does the system provide the data, but it tells us what we need to do with it. We're able to start thinking about possible solutions before we arrive on site."
Optimized pump starts and runtimes help CJUC reduce energy consumption.
CJUC's total investment to rehabilitate the existing CJUC system was $3.5 million. The municipality saved $9.5 million by opting for rehabilitation instead of a total system overhaul. The cost of the Mission system was a small part of the investment.
"The decision was a no-brainer. I couldn't place that sort of burden on our community when I didn't have to," Wallace explained. "Instead, we sought out innovative products that would fulfill the collection system needs along with the needs of the community."
Since the system upgrade, CJUC has lowered operation and maintenance by an average of $98,000 per year. Annual pump station flow has been reduced by 36 million gallons. CJUC has also instituted a successful program to reduce energy usage. An initial energy management system installed at the wastewater treatment facility revealed multiple areas of high energy consumption. CJUC set six aerators to cycle on and off for optimal energy use. Pumps were optimized to consume less power. These sustainability measures saved $18,000 and 200,000 kWh of power in the first year of operation. CJUC now averages an annual $21,500 in energy savings. The overall savings are due to infrastructure rehabilitation, equipment efficiencies and improved oversight.
In 2011, the CJUC joined the Tennessee Water and Wastewater Energy Efficiency Partnership to continue sustainability efforts. The partnership included EPA Region 4, the Tennessee Department of Environment and Conservation and seven neighboring utilities. Joint participants achieved a combined annual carbon dioxide emission savings of 6,696 tons. The CJUC was awarded the EPA Outstanding Leadership and Successful Organizational Achievements award for its role in sustainability.
"The decisions we made throughout the past several years helped us create a more sustainable system," explained Wallace. "The Mission Communications system is incredible. The data that it provides was a vital part of helping us to identify our inefficiencies within the system."
CJUC could have chosen another and ultimately more expensive solution. Instead, they chose to rehabilitate. This decision has made the CJUC an award-winning utility that will continue to serve its community for future generations.
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