Practical design stretches resources further
Since the passage of the Jobs and Transportation Act, ODOT has been implementing Practical Design, which lays out principles for delivering transportation benefits in the most cost effective manner. Three years in, ODOT has seen this effort bear fruit, saving tens of millions of dollars while allowing the agency to deliver projects that improve the transportation system and balance the needs of the community with the context of the corridor.
Two of the key values of practical design that have changed ODOT’s approach to projects are optimizing the system and efficient cost. Under the principle of optimizing the system, engineers move away from developing an optimal design for each project to focus on optimizing the transportation system as a whole. Rather than building one perfect project that addresses all identified issues in an optimal way at significant cost, practical design may allow ODOT to build several very good projects with an overall greater benefit to the public for the same amount of money. Incorporating the principle of efficient cost into the design process means that cost becomes a key consideration on every project, and efforts need to be made to ensure that projects efficiently use public dollars.
Within practical design, safety is a fundamental value that is never compromised, and every project will improve safety. But when safety is considered within the context of the entire system in addition to the individual project, incremental improvements become cost effective options to be considered if they improve the overall safety of the corridor.
“Practical design is a shift from a rules-based design system where engineers apply a set of standards in a manual to one in which engineers are asked to solve problems based on values,” Paul Mather, ODOT Highway Division Administrator, told the Oregon Transportation Commission in a recent presentation.
ODOT began this process by developing a practical design strategy and has since moved into institutionalizing the strategy by training ODOT staff on how to incorporate practical design into projects and working practical design into the agency’s practices.
“When we went to implement practical design, we learned that we were already doing many of the foundational items. But we lacked a systematic way of making practical design decisions on projects,” said Cathy Nelson, head of ODOT’s Technical Services Branch and the leader of the agency’s practical design efforts.
A number of projects have used practical design principles to modify standard design practices in ways that improve the transportation system while fitting within limited budgets, allowing the agency to stretch scarce resources further.
The Jobs and Transportation Act provided funding for the next phases of the I-5 Beltline Interchange. Using practical design, ODOT modified the original optimal design slightly by lowering the design speed. This reduced the need for a separate bridge and allowed for a shorter ramp, saving about $20 million without compromising safety or efficiency. This put the project within the budget available under the Jobs and Transportation Act.
This project constructed a continuous auxiliary lane just south of the interchange of I-5 and Highway 217 to help ease congestion at this chokepoint where two massive streams of traffic converge. Because of the constraints of building within an urban area, an optimal design for this project would be prohibitively expensive. However, the project team used practical design to lower the design speed so that an auxiliary lane could fit within the constraints at a low cost, delivering congestion relief at a reasonable price.
US 26 (Powell Boulevard) from I-205 to 174th
This project, which is still in the preliminary design stage, is examining the entire US 26 corridor east of I-205 to Gresham using a practical design approach to solve safety and operational issues. The initial project scope focused on full reconstruction of 14 blocks of Powell Boulevard to address high crash rate sites. However, optimizing this one individual project exceeded the dollars available for the project and left the remainder of Powell in an unimproved condition. Utilizing practical design, ODOT’s Region 1 and stakeholders are developing a menu of incremental improvement options (including paving, striping, sidewalks, traffic signals/cameras, and others) to meet priority safety and operational needs for the entire corridor within the funds available.