Public Interest Transportation Forum -

Least Cost Planning in Puget Sound Regional Transportation Plans

Has NOT been Implemented in the State of Washington, But it Should Be!

by John Niles

Dick Nelson and John Niles of Seattle in 2016 formed a non-profit association Advocates for Regional Transportation Efficiency (ARTE) that strives to have State of Washington effectively implement the Least Cost Planning (LCP) methodology that was established by State  law in 1994.  A simple explanation of what Least Cost Planning means for public transit was presented in a Seattle Post-Intelligencer op-ed by Nelson and Niles published February 8, 2001 and posted here.  That essay explains what LCP means for transit, as follows::

Since reducing congestion and pollution is what people say they want from transit, the effectiveness of an investment in transit will be largely determined by the number of new riders it produces. New riders are those who previously drove, as distinct from current bus riders who shift to the new form. With the predicted number of new transit users in hand, planners can begin to sort out the benefits of providing the service and reach a conclusion as to its cost-effectiveness.

New transit riders yield benefits in the form of time saved, driving reductions and environmental improvements, all of which can be converted to dollars and compared to the estimated costs to construct and operate the new system. Widely different transit technologies can be compared. Even proposals that do not require new construction, such as strategies that add buses and van pools to HOV lanes or fill existing buses more completely, can be evaluated by this technique. The most cost-effective investment is one that produces the greatest margin of benefits over costs.

In August 2016, ARTE submitted a petition to Washington State Department of Transportation (WSDOT) to substantively amend the simple State Government rule that governs execution of LCP for high-capacity transportation planning like that carried out by Puget Sound Regional Council and Sound Transit in the central Puget Sound region.  In September 2016, that petition was denied by WSDOT in a letter from the Washington State Secretary of Transportation.

On October 27, 2016, ARTE submitted an appeal to the State Governor to overturn the WSDOT denial of the request to update the LCP rules for State of Washington.  On December 7, 2016 the appeal was rejected by Governor Jay Inslee.

Earlier in his career, Dr. Dick Nelson served as a State Legislator, and assisted in writing legislation that made Least Cost Planning mandatory in Washington's transportation planning. That legislation passed in 1994.  Nelson's involvement continued in collaboration with the late Don Shakow to conduct a series of studies elaborating the concept.  Some of that work is posted at

Here is the history of what happened in metropolitan Seattle in previous years on Least Cost Planning

In 2004 Sound Transit critics reopened the long-standing call for the evaluation of transportation alternatives by Puget Sound Regional Council (PSRC) according to the Least-Cost Planning (LCP) methodology required by Washington State law.  On June 24, 2004, the chair of the Transportation Policy Board of the PSRC announced that she would take up this question in future meetings of the Board.

Almost six years later, the PSRC Transportation 2040 Metropolitan Transportation Plan approved May 10, 2010 includes a description of the benefit-cost analysis tool that eventually resulted from PSRC's response to the LCP mandate. That description is in Appendix H.  PSRC now regards LCP as a form of benefit-cost analysis.  A letter from PSRC to the ST3 Expert Review Panel describes the 2016 status of Least Cost Planning as a methodology in the Seattle metropolitan area.

The controversy reignited in 2004 is over what this law means for government transportation planners. PSRC is interpreting Least Cost Planning in a different way than what the law authors intended, and what many others believe is a common sense approach to deciding how to spend public money to improve the environment. Least -cost planning for transportation investment decisions in the Puget Sound region grew out of the WPPSS energy debacle of the 1970s and 80s.

Victoria Transport Policy Institute's Online TDM Encyclopedia has an entry on Least Cost Planning providing a worldwide, multi-modal perspective.

While Puget Sound activists have aimed their activities at finding cost-effective public transit investments, LCP can also be aimed at alternatives to road investments. As noted in the Online TDM Encyclopedia, "Least Cost Planning means that transit improvements, rideshare programs, or road pricing can be implemented instead of roadway capacity expansion if they improve mobility at a lower total cost, including costs to governments, businesses, consumers and the environment. If a particular demand management strategy can reduce traffic or parking demand by 10%, it is considered to be worth at least as much as a 10% increase in road or parking facility capacity, and often more when indirect impacts, such as environmental and safety impacts, are considered.

An earlier push to implement LCP was made in late 2000 as the PSRC's Metropolitan Transportation Plan called Destination 2030 was being prepared. The history is revealed in a series of letters to PSRC from citizens, and documents from PSRC in response, summarized below and posted full text here in Public Interest Transportation Forum.

Least Cost Planning Push in 2000-01

The opening shot was fired in September 2000 by a letter from PITF co-editor Dick Nelson and seven other independent regional transportation professionals to PSRC that began as follows:

"We are transportation, land use, and other technical professionals who have a strong interest in the application of least/full cost principles to transportation planning in this region. We are writing to express our concern with the apparent intent of your agency to limit the application of least-cost analysis to alternative "packages" and not apply it to the individual components of those packages." 

This letter was followed by public testimony and recommendations from Dick Nelson in October 2000,  which included these recommendations:

  1. As required by state law (RCW 47.80.030), apply least-cost planning to individual transportation plan elements (facilities, services, and programs), including those that are credible and under discussion in the region but not currently adopted.
  2. Provide a new comment deadline for the DEIS that allows the public to review and compare the cost-effectiveness (net social benefit) of individual transportation elements.
  3. Submit the least/full cost analysis to a panel of nationally recognized transportation economists for their review and comment.

In response, PSRC issued a new 23 page Technical Appendix 11, available full text in the compilation document posted on PITF. The Appendix included the comment:

"[T]his is the very first effort to conduct such analysis for a regional transportation plan in the state of Washington. While this analysis should provide a useful focus to help shape the broad policy directions and implementation strategies to be incorporated in Destination 2030, it should be seen as only the beginning of a new way to look at optimizing cost effectiveness information for making major investment and policy decisions in regional transportation plans."

In response to that Technical Appendix, citizens submitted comment letters, one of which is posted here, along with the published response from PSRC that is required by law.  The complete collection of citizen comments on the Least Cost Planning Technical Appendix and the responses from PSRC, are in a compilation document posted here.

The comment letter from Dick Nelson, et al,  concluded,

We assess the current use of least cost planning by PSRC to be deficient with respect to state law. We make the following strong summary recommendation which would correct the deficiency:

Least-cost analysis of all potential transportation plan components, whether investments or strategies, whether additions to system capacity or policies that produce more efficient utilization of current capacity, and whether sponsored by a governmental agency or a group of citizens, should be accomplished prior to selection of the preferred alternative and adoption of the MTP. The results of this analysis should serve as the basis for selection of the preferred alternative plan and should be incorporated in the final DEIS.

To be clear, this recommendation means that we believed considerable rework of the 2030 Metropolitan Transportation Plan by PSRC was required before adoption.  This did not happen.

PSRC's response to this charge in the Final EIS for Destination 2030 was as follows:

The Regional Council believes it has complied with state law (RCW 47.80.030); any further refinement and utilization of a least-cost analysis methodology simply provides additional information that can be used in future decision processes as they arise.

Washington State DOT has adopted regulations pursuant to RCW 47.80.070 to establish minimum standards for development of regional transportation plans. WAC 468-86-030 defines "least-cost planning " as "a process of comparing direct and indirect costs of demand and supply options to meet transportation goals and/or policies where the intent of the process is to identify the "most cost-effective mix of options." The Regional Council believes that this phrasing supports doing least-cost planning for the "mix of options " rather than on each option separately; if it required a least-cost analysis for each of the components, this phrase would read "the mix of the most cost-effective options."

The Regional Council believes that the best way for the least-cost methodology to "treat demand and supply resources on a consistent and integrated basis " is to put the alternatives into packages based on consistency and integration, and then do a least-cost analysis to see which package is most cost-effective. This was the methodology employed in Appendix 11.It appears that the intent of the statutory amendment (WAC 468-86-080)was for the regional transportation planning organizations to implement least-cost planning methodologies incrementally and for WSDOT to lead the way in how that should be accomplished. The Regional Council ’s Destination 2030 plan requires that enhanced benefit-cost analysis be conducted on all future corridor projects before a given project can be "approved " for implementation.

The last shot fired in the 2000-01 campaign to have Least Cost Planning included as part of the Destination 2030 MTP document was a public comment by John Niles to the PSRC Assembly on the day of the MTP's adoption, May 24, 2001:

"[T]he handling of the official request made by elected officials for more information on all-bus alternatives for high capacity transit is disturbing. The official request was made in the context of the MTP exploring all reasonable transit options to find the most cost-effective ones. There was time for Council staff to prepare a response in the spirit of least-cost planning, but that wasn't done. There was time for a fresh look in the face of remarkable developments in the past few years with modernized bus and guideway technology involving electronics, computers and new energy-efficient, non-polluting propulsion systems and new Federal initiatives on Bus Rapid Transit. But that wasn't done. No, the official Council response to the request -- included on the CD-ROM, thank you very much -- was a review of pre-1996 history that raises far more questions than it answers."

What PSRC eventually reported on Least Cost Planning in the published Destination 2030 document is quoted in its entirety as follows:

PSRC's Summary of  Least Cost Analysis in Destination 2030

In the State of Washington, beginning in 2000, Regional Transportation Planning Organizations are required (RCW 47.80.030) to apply least-cost planning analysis to alternative transportation investment strategies. Within Washington Administrative Code (WAC 468-86-030 and WAC 468-86-080)least-cost planning is defined as “a process of comparing direct and indirect costs of demand and supply options to meet transportation goals and/or policies where the intent of the process is to identify the most cost-effective mix of options. ”Least-cost planning attempts to consider all of the resource costs associated with alternative investments, and to provide information relevant to decisions about investment selection and prioritization. Least-cost planning combines elements of strategic, systems level planning with the accounting framework of benefit-cost analysis.

The Regional Council applied the methods of least-cost planning analysis to the systems level transportation alternatives contained in the Metropolitan Transportation Plan Alternatives Analysis and Draft Environmental Impact Statement, published in August 2000.Other analysis might address a broader range of policy and investment questions. This type of analysis is not an exact science, and is subject to the influence of analytical uncertainty. It is not meant to be a substitute for common sense, or political judgment. It is meant to supplement the available information that can aid decision-makers as they face complex choices about alternative investments in future transportation systems. Least-cost analysis provides some insight into the cost effectiveness, and the cost components of different plan alternatives. The following major planning lessons can be drawn from the least-cost analytical exercise:

• Least-cost analysis tells us something about the cost effectiveness of alternative ways of serving a static number of trips but does not fully compare the marginal cost and marginal benefit of the different transportation system alternatives.
• Least-cost analysis of system level transportation alternatives can provide significant information relevant to the decision process.
• Least-cost principles can guide the development of the system elements of a preferred alternative.
• Systems level least-cost analysis of transportation planning alternatives is not a substitute for corridor, project, or program level benefit-cost analysis.

Least-cost analysis is concerned with changes in transportation systems, over the long run. Over time, all transportation costs are variable and are appropriately considered to be influenced by the types of transportation system decisions made. Significant findings from the least-cost analysis of system alternatives include the following:

• When faced with a large increase in the demand for trip-making, regional transportation systems begin to perform poorly if only small actions are taken to directly address additional travel demand.
• Addressing environmental and congestion problems through capital intensive supply side solutions is expensive.
• Programs that manage transportation systems for more efficiency and that offer opportunities to meet travel demand through shorter, higher occupancy, off-peak vehicle trips (or using no motorized vehicle at all) may significantly reduce costs beyond the projects and programs analyzed in the Draft EIS.
• In addition to capital infrastructure costs and congestion costs, one of the most critical variables relating to total transportation system costs (public and private) is the total vehicle miles traveled for all personal travel trips.

Even earlier, some thoughtful commentators advocated that Least Cost Planning be applied to Puget Sound transit in The Seattle Times, May 10, 1995: "Regional transit: learning the hard lessons of WPPSS" by John A. Baden, Ph.D. and Eric H. Espenhorst
And earlier still, during 1993, the Bullitt Foundation in Seattle funded two professionals familiar with least cost planning from the NW Power Planning Council to make an assessment of how LCP would apply to transportation.  Richard Watson, a former director of the Washington State Energy Office and a pioneer in positioning telecommuting as a transportation demand management tool, reported on his work for Bullitt to an early board meeting of the Central Puget Sound Regional Transit Authority, December 10, 1993.  Minutes of that meeting are available for download here.

In the mid-1990s, Puget Sound Regional Council had published a series of papers on least cost planning (pdf):


A Primer for Policymakers: Integrated Transportation Planning, June 1995


Technical Memorandum Regarding Procedural and Analytical Issues Associated with Implementing Integrated Transportation Planning, June 1995


Case Study: Testing Application of Integrated Transportation Planning Methods on System Level Evaluation, June 1995

Public Interest Transportation Forum stands on the point made by critics in autumn 2000 that individual system elements (such as Central Link Light Rail and HOV alternatives such as Bus Rapid Transit) are by law supposed to be analyzed individually, in order to guide system level decisions about the most cost-effective packages of many elements that may include light rail or not.

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Last modified: October 28, 2016