By Brandon Buckner & Will Jernigan
Nestled near the Great Smoky Mountains National Park in western North Carolina, the City of Asheville has much to boast about — including quality of life, a vibrant arts culture and more microbreweries per capita than any U.S. city (that’s roughly 100 local beers!). In fact, the Asheville area recently became home to the second brewing sites for Sierra Nevada and New Belgium. Part of the draw for these breweries, apart from the population’s demand for beer, has been the area’s water — which comes in plentiful supply and of the highest quality. It makes for an interesting case study, especially when it comes to managing water loss — water extracted from the rivers or aquifers but lost largely due to aging infrastructure. Those headlines are usually dominated by the cities in the western arid states.
Enter the City of Asheville, which has put itself on the national water loss management map despite having no constraints on available supply and no mandating regulation to address it. Asheville formally launched its non-revenue water (NRW) program in 2012, focusing heavily on the identification and reduction of water losses, recognizing that efficiency gains in water loss reduces costs, improves revenues and serves to mitigate risk for future water supplies. Water loss control also means better management of the water system and better serves the long-term interest of the ratepayers.
A Starting Point
An audit of the water system in the early 2000s found the city produced 21.5 million gallons of treated water each day but lost nearly 7 million gallons per day, or approximately 30 percent. While the city has abandoned the use of “% of supply” to track water loss performance due to its unreliability, this initial assessment served to catch the attention of the managers and elected officials.
Over the subsequent years, the city invested in large scale capital projects to replace millions of dollars of its distribution pipe network, and a wholesale replacement of its roughly 55,000 customer meters. This set the stage for its formal NRW program launch in 2012, following attendance to the AWWA Distribution System Symposium in St. Louis by key staff. Upon return from this conference, system managers established a framework of teams each focused on a different aspect of NRW. Setting up any NRW program requires a team effort from various roles, committed to regular inter-departmental communication of accurate data including but not limited to supply, billing, consumption, metering, costs and other operational data.
An audit of Asheville’s system in the early 2000s found the city produced 21.5 million gallons of treated water each day but lost nearly 7 million GPD, approximately 30 percent.
Not a Solo Sport
The City of Asheville recognized the need for a concerted NRW team. The NRW team was developed with the following groups and focuses:
Audit Input Team: Responsible for tracking and collecting the various points, but has procedures in place in order to validate the information as it is compiled.
Valve & Leak Team: Dedicated team that focuses on proactive leak detection and repair, and control valve maintenance.
Unbilled Customer Team: Responsible for analyzing potential illicit use on unmetered fire service lines and other unmetered connections.
Customer Service Team: Responsible for account coding cleanup, billing software migration cleanup, and revenue recovery calculations.
Metering Team: Oversight of Automated Meter Reading (AMR) conversion, planning and execution of the large and small meter testing programs
Pressure Team: Maintains pressure database, confirms pressure boundaries and provides input for pressure optimization and District Metered Areas (DMAs).
All water systems have water loss — only the extent and composition varies. Each of the teams established work plans with prioritization based upon the water loss components in the baseline (2012) American Water Works Association (AWWA) water audit. The metrics utilized by the City of Asheville are water loss component volumes, their associated values and the overall audit validity as a measure of reliability. This approach for separating and ranking water loss components by their volumes and values have enabled the city to identify where resources should be directed, and more importantly, where they should not be directed. Once work plans were in place, a routine framework was established for communicating progress updates, as well as meeting to evaluate program effectiveness and to chart the course for the next steps. The city has seen first-hand that dedicated teams, regular communication and accountability are core necessities for its NRW program.
Tying NRW to the Capital Program
While auditing, establishing focus teams and putting the NRW program into place fall comfortably into the city’s operations, there have and continue to be considerable capital infrastructure projects that take place each year. Recognizing that NRW is, at its core, driven by the infrastructure, the city sought to ensure a healthy tie between the two efforts. A few exemplary projects are highlighted here.
Leakage and pressure management are also very significant components of the city’s NRW program. With more than 1,500 ft in elevation change, more than 50 pressure zones and some pressures as high as 400 psi, pressure and DMA projects rise to the top of the capital projects list. Using existing zone configurations in 2015, the city installed 23 master meters to existing pressure zones to launch its DMA efforts.
All water systems have water loss — only the extent and composition varies.
The zone input flows are tracked in conjunction with tank drops in order to monitor nighttime flows to identify which zones are exhibiting actionable leakage levels. The DMAs have been online for several months and have already allowed the Valve & Leak Team to considerably streamline its efforts.
Another capital project, known as the Fairview Project, involved storage and piping modifications that were made in one particular high pressure zone. The project identified a need for redundant storage as well as pressure reduction, anticipated pressure reduction of over 100 psi with increase in fire flow for nearby schools, and improved water quality by getting rid of dead end lines. While the project was not originally conceived for the purposes of improving water loss, with the substantial pressure reduction, that zone has observed lower overall leakage rates and a reduction in the frequency of main and service line breaks.
The Haw Creek pressure optimization study was implemented to identify the business case for pressure modifications.
Another capital project launched under the NRW banner is known as pressure optimization, starting with a pilot study in two zones: Haw Creek and Spivey. The aim of the pilot, conducted in 2015, was to identify the business case for pressure modifications — considering the cost basis in the zone for leakage, main and service break frequency, pumping energy consumption, and the extension of useful life on the pipe assets. In the Spivey zone, a business case for no action was determined. However, in the Haw Creek zone, a payback of 2 months was determined for implementation of pressure optimization, as the whole zone was over pressurized on the order of 50 psi — incidentally not an uncommon occurrence in hilly terrain where some homes built atop the hill sit in excess of 200 ft above the meter box. Even with the additional customer coordination on a handful of homes requiring supplemental boosting, the business case was compelling. The zone also experienced transient pressure surges on a routine basis, which was contributing to main and service line break frequency.
Bridging the Divide
The city’s formation of focused teams within the organization, in and of itself represents an exercise of communication and inter-departmental dynamics. It’s a fact of life — it takes a lot of people of various expertise to make a water system run — engineers, operators, technicians, accountants, customer service and managers just to name a few. This exemplary communication extended outside of the city staff as well, as the city’s water system is also home to 20 fire departments throughout the city and county. The audit team set out and met with each of these departments to establish a communication, and develop a better understanding of their water uses. This also allowed the city to migrate to a uniform policy for metering and billing of non-suppression type fired department uses.
City of Asheville’s water loss in MGD, 2009 to 2016.
The Good Kind of Nose Dive
The city’s NRW program results are compelling. These results did not occur in a single year, but rather are an aggregate result of putting the right attention on the right parts of the problem with consistency. Since its formal launch in 2012, Asheville’s NRW program has seen steady reductions in water losses — nearly 2.5 million gallons per day of reduction. The city has observed growth in demand during this same time (breweries notwithstanding), and as a result has enjoyed the accommodation of system growth without increasing volumes extracted from the source.
City of Asheville’s AWWA water audit data validity.
In this same period, the city has also steadily improved its audit reliability — as measured by the AWWA Data Validity Score — through the continued implementation of best management practices including source meter testing, customer meter testing, and billing system data analytics. The NRW program has demonstrated an improvement to employee engagement in the mission and overall operational cohesion between departments, fed by more efficient communication and improved business processes.
The efforts and results from Asheville’s NRW program have earned it accolades including being featured in the latest version of the AWWA Free Water Audit Software and M36 Manual for Water Audits & Loss Control, as well as invitations to present on the national stage at conferences dealing with water loss management subject matter. Looking ahead, the city’s next frontier includes achieving and maintaining its economic water loss targets, and further expansion of DMAs and pressure optimization across the distribution pipe network.
About the Authors
Brandon Buckner | Meter Services Division Manager, City of Asheville Water Resources Department
Brandon Buckner is the meter services division manager for the City of Asheville Water Resources Department. Prior to this, he served as the Operator Responsible in Charge for Backflow/Cross-Connection Division with the city. Buckner’s leadership has been essential to Asheville’s NRW success, as he has served as co-chair to the NRW program since its inception in 2012.
Will Jernigan, P.E. | Director, Cavanaugh
Will Jernigan, P.E., is a director with Cavanaugh and nationally recognized leader in water loss management and bioenergy. He has 15 years in the industry and is active with AWWA as a trustee with the Distribution & Plant Operations Division, vice chair of the AWWA Water Loss Control Committee, chair of the WLCC Software Subcommittee and Annual Water Audit Data Initiative, a principle contributing author on the M36 Manual for Water Loss Control, 4th Edition, Chair of the inaugural North American Water Loss Conference and member of the IWA Water Loss Specialist Group.
