By: Mike Matichich

Vital statistics

WHO: Upper Occoquan Service Authority (UOSA), Centreville, Va.
SIZE OF TREATMENT WORKS: 54 mgd
SERVICE AREA POPULATION: 275,000
2010 OPERATING BUDGET, INCLUDING DEBT SERVICE: $61 million
CAPITAL BUDGET THROUGH 2021: $437 million


The Upper Occoquan Service Authority (UOSA) was formed in the 1970s to treat wastewater for four jurisdictions in the Occoquan Watershed, a rapidly growing suburban area 25 miles west of Washington, D.C. Originally 15 mgd, the facility was expanded in 1989, 1995, and 2005.

In addition to keeping the facility in sound working order, the operation's capital improvement program must address mandates that include further expansion of the delivery system and a nutrient-reduction program designed to protect and restore the Chesapeake Bay. With some assets nearing the end of their reliably useful lives, in 2008 the authority embarked on an asset management program to guide decisions regarding renewal and replacement.

ASSET HEALTH AND OPERATIONAL CULTURE

Recognizing that tight economic times require investments to be highly targeted, managers adopted a risk-based approach for allocating resources. “The recession put significant strain on our capital budget,” says Executive Director Chuck Boepple. “We conducted these evaluations to make sure that we use our customers' dollars wisely, focusing renewal and replacement dollars on the assets whose failure would pose the greatest risks in accomplishing our mission.”

Documents such as Implementing Asset Management — A Practical Guide, published by the Association of Metropolitan Water Agencies, the National Association of Clean Water Agencies, and the Water Environment Federation in 2007, provide the starting point for assessing risk elements. But it's equally critical that the evaluation framework also represent the values, priorities, target service levels, and data situation of the specific agency.

We convened three workshops over two months with employees who were familiar with the authority's assets, mission, and vision. Using a 10-point scale, they identified individual components, assigned a weight to each, and defined how the contribution to failure should be scored for each asset or asset group.

Health & Safety and Permit Compliance were given the most weight in evaluating the consequence of failure. For the former, even minor injuries with no lost time were considered a moderate “consequence” outcome. For the latter, the asset had to cause chronic permit violation or result in pending enforcement action to receive the most severe rating.

As for assessing the likelihood of an asset failing, Physical Condition emerged as the most significant factor. But — and this is very important — Performance and Repair History were also regarded as significant considerations.

Because of the importance of physical condition to the risk equation, the authority assessed the condition of key assets. Over eight weeks, 1,912 pieces of mechanical and electrical equipment, pumps, and instrumentation, as well as facility infrastructure such as roofs and concrete, were inspected and rated. Six experienced operations employees evaluated the assets while a group of design engineers focused on plant infrastructure.

Before arriving onsite, authority managers gave the latter a list of assets from their enterprisewide JD Edwards maintenance management system. The evaluation team worked with authority employees to refine the database for field use and limit the evaluation to older assets. To more closely evaluate the condition of relevant architectural, structural, electrical, and building services components for the facilities being evaluated, though, several “new” assets, such as roofs, building skins, and HVAC equipment, were included as well.

The completed questionnaire was loaded onto handheld tablet computers for use by the field teams. The information gathered in the field was then loaded into our proprietary asset-condition evaluation system (ACES) software using the authority's existing equipment identification numbers so condition-assessment information could be transferred back into its maintenance management system upon project completion.

In addition to the condition assessment, scoring was completed for the other elements of risk — performance and repair history — that employees had identified.

THE HIGHEST–RISK ELEMENTS EMERGE

The condition assessment provided a detailed evaluation of each key asset, as well as a profile of the overall condition of the authority's asset inventory as a whole. The combination of condition and other assessments enabled managers to rank assets based on the overall level of risk associated with failure, a key aid in prioritizing them for renewal or replacement.

They used this information to refine their list of capital projects, scheduling projects with risk-reduction opportunities clearly in mind. Ultimately, determining which projects to advance — and when — was based on a number of factors to achieve the following objectives:

  • Maintain reliable service to customers at levels consistent with the mission
  • Provide access to financing at reasonable interest rates
  • Keep bonding programs and rate increases at levels that support affordable rates
  • Address the demands of other projects, such as those necessary to support growth and development needs.
  • Project timing also depends on such factors as bundling related activities and sequencing projects that should be done in tandem or sequentially from a delivery and constructability perspective.

    With the completed condition assessment and related risk scoring, managers have much better information than previously existed on a key input to investment decisions. The analyses helped them divide identified capital projects into two phases, the first focused primarily on those that address the greatest identified risks.

    “It would've been much more difficult to put together a coherent plan that fits within our financial means,” Boepple says. “The analyses helped us identify projects that needed to proceed immediately versus those that could slide back a few years if necessary.”

    For example:

  • An in-house program to modernize the computer platforms for the plant's control system was accelerated due to the significant risk associated with failure of those particular assets.
  • A project to rehabilitate tertiary treatment facilities can be pushed back a few years because doing so poses limited near-term risk.
  • A project to address portions of the biological treatment system was accelerated because of new regulatory requirements.
  • Boepple and his team are using the results to develop next year's budget and work with their financial team to identify bonding needs for the next several years. Beyond that, they intend to continue using their risk-informed framework to focus future resources toward projects that address assets whose failure poses the greatest potential risk.

    — Matichich (michael.matichich@ch2m.com) is global technology leader, Financial Services, for CH2M Hill. Reach Chuck Boepple at chuck.boepple@uosa.org.