CASE STUDIES AND VALUE OF RESEARCH
WaterOne Applies Foundation Research
to Prioritize Pipe Replacements
Dan Smith, Waterone
As water systems age, the need for infrastructure replacements through asset management programs becomes
greater and greater. Water District No. 1 of Johnson County, Kansas (WaterOne) is a relatively young utility but the
corrosive soils within its service territory has taken a toll on the buried infrastructure necessitating the need for an
asset management program. As WaterOne has developed its asset management program, it has looked to WaterRF for
guidance on various issues, such as pipe replacement, renewal, and corrosion.
WaterOne serves over 400,000 people in 17 cities of a growing, affluent section of the Kansas City metropolitan area.
WaterOne has over 2,500 miles of water mains with some approaching 100 years of age in a service territory covering
272 square miles. The pipeline materials consist of cast iron, ductile iron, PVC, PCCP, HDPE, and AC.
Historically, WaterOne has done an excellent job of planning for the future water supply needs of the utility by
developing a master water supply plan that forecasts production, transmission, and distribution needs 20, 30, and 40
years into the future. These plans are then built into the utility’s financial model for capital planning needs and for the
issuance of bonds for financing of the water supply master plan.
In the late 1990s, WaterOne recognized that a major component was missing from the financial model. That
component was the inclusion of funding for replacing aging infrastructure. The Water District has been developing
asset management programs for both its distribution and production facilities to deal with its aging infrastructure since
early 2000. Replacement programs and monitoring of its assets are now incorporated into the Water District’s long-term financial plan.
The most difficult asset to address is buried infrastructure since it cannot be seen except when it ruptures or is
excavated for a tap or relocation. WaterOne retained consulting services to develop a Nessie Model of its buried assets
so it could begin the process of identifying what classes of assets were most likely in need of replacement and to assist
in the overall financial planning needed for buried assets. Once this was completed, a more detailed approach was
necessary to identify specifically which pipes needed to be replaced.
WaterOne’s engineering staff worked closely with its IT/geographic information system (GIS) department to develop
an in-house pipe replacement prioritization schedule (PRPS). The PRPS utilizes various data available through the
utility’s GIS system and business management software (BMS) to create a prioritization schedule that is based on eight
categories. One of the categories is directly based on the financial viability of the proposed replacement utilizing a
financial break-even formula developed in Water Research Foundation (WaterRF) report, Decision Support System
for Distribution System Piping Renewal (2002, order #90892/project #2519). The list of criteria is as follows, in no
order of importance:
• Financial break-even formula
• Break history, breaks/miles/year
• Pipe diameter
• Pipe material
• Pipe age
• Corrosiveness of soil