Annette Huber-Lee, Chris Swartz, John Sieber, James Goldstein, David Purkey, Charles Young, Elizabeth Soderstrom, James Henderson, and Robert Raucher

OBJECTIVES:

The main objective of this project was to develop a computerized decision support system (DSS) tool that will allow utility strategic planners to effectively evaluate options for managing and developing reliable, adequate, and sustainable water supplies for their customers over the next 50 to 100 years. This tool will allow for the evaluation of multiple future water management scenarios that include integrated social, financial, and economic analyses that are requisite to sustainable, long-term water supply planning.

BACKGROUND:

This effort was distinguished from traditional water utility planning efforts in its focus on sustainability and a longer planning horizon. As such, a wider array of management objectives and opportunities were brought into consideration, requiring a tool that extends beyond sequencing potential supply enhancements in response to unrelenting, unmanaged increases in demand. The longer planning horizon allowed for consideration of a wide range of alternatives on both the supply development and demand management sides.

HIGHLIGHTS:

The research identified, through a utility-attended workshop, priority elements of a water planning DSS. The research also demonstrated that an integrated DSS framework can facilitate the analysis of actual utility-defined future scenarios dealing with long-term sustainable water planning--analyses that comprise multiple elements associated with a range of common planning challenges facing water utilities. In addition to a financial planning module added to the DSS, there may also be a widespread need for research on ecosystem flow needs (both quantity and quality), social cost accounting, and demand management that can be translated into additional modules.

APPROACH:

The research team adopted, refined, and enhanced the Water Evaluation and Planning (WEAP) software system for use as a relevant drinking water industry DSS via substantial interactions with three test site water utilities (Austin, Texas, Philadelphia, Pa., and Portland, Ore.), each facing distinct challenges in long-term sustainable water planning. These collaborations included (1) an initial planning and prioritization meeting with each utility; (2) collaborative development of a first draft DSS; (3) defining, developing, and implementing enhancements to the DSS; (4) implementing scenarios of interest to each utility; (5) reviewing results; (6) reporting on finds to each test site utility; and (7) synthesizing findings of all three test site utilities as recommendations for use of the DSS by the drinking water industry.

RESULTS/FINDINGS:

In collaboration with the test site utilities, the research team demonstrated the usefulness of a computerized DSS for development of long-term sustainable water supply plans. Issues encountered and addressed in an integrated fashion included the following: (1) the timing of investments in future facility expansions; (2) investments in demand management and water reuse and recycling; (3) the coordinated operation of multiple supply sources; (4) changing environmental regulations; (5) service area expansion and regional coordination; and (6) water supply and wastewater treatment management to improve the status of receiving water bodies. While not comprehensive, these planning issues are common to water utilities and the research demonstrated that an integrated DSS allowed for analysis of future scenarios comprised of multiple elements. For example, at one test site utility it was possible to evaluate a set of scenarios whereby facility enhancement actions were sequenced differently in response to different assumptions about the coordinated operation of surface water and groundwater, the minimum flows required to comply with the Endangered Species Act, and the number of wholesale customers included in the utility service area. This sort of integrated analysis is very powerful and is made possible by an integrated DSS for water supply planning.

IMPACT:

Water industry DSS tools must confront the diversity and utility-specific nature of planning challenges and the range of current reliance on such tools. For utilities already utilizing DSS tools extensively, the overarching recommendation is that these tools be benchmarked against an integrated system like the WEAP-based DSS and assessed for their ability to respond to a fuller spectrum of considerations important to long-term sustainable planning. Where less investment has been made in DSS tools, a test application can illuminate integrated analyses that support sustainable water supply planning and whether these opportunities would be more difficult to distinguish using separate tools.

MULTIMEDIA:

The report included a CD-ROM with the Water Evaluation and Planning (WEAP) software and a User Manual.

PARTICIPANTS:

• City of Austin (Texas) Water Utility

• City of Philadelphia (Pa.) Water Department

• City of Portland (Ore.) Bureau of Water Works