Structures Engineer David Graff. P.E. Embraces Projects That Challenge Assumptions of What is Possible
December, 2021
From a utilitarian standpoint, bridges serve a singular purpose: they enable the crossing of obstacles via the most direct route possible. For Bridge Project Engineer, David Graff, P.E., this strict interpretation of bridges held true, especially when viewed through the lens of accommodating vehicular traffic. That all changed when he joined Otak’s Structures Group in Colorado and began working on pedestrian bridges.
In 2017, David had recently completed the engineering graduate program at the University of Colorado Boulder (CU), where he had intentionally pivoted away from his previous structures work in buildings and cell towers, to focus on bridges. He says that he found “vehicular bridges to be very interesting and cool projects to work on.” During this same time, Otak expanded its operations in Colorado and merged with Loris and Associates, where David was working. He was familiar with Otak, having originated from Portland, and he saw the merger as an opportunity to be a part of a collaborative environment and work with professionals from other disciplines.
David credits Otak Project Engineer and Structures Group Manager, Dan Beltzer, P.E., with introducing him to pedestrian bridges. He says, “the thought of working on pedestrian bridges had never really entered my mind.” Dan shared some of the projects they were working on at the time, which included a number of pedestrian bridges. “He showed me the very first iterations of the 23rd Street bridge on CU’s campus, and there was no looking back. I thought, ‘now this is the project I want to work on’.”
As David explains, “the vehicular bridges that Otak works on tend to be very interesting in and of themselves, but with pedestrian bridges, the location of the project often adds another dynamic and an opportunity to really interact with the landscape.” One aspect he enjoys is how pedestrian bridges tend to be nature-oriented, providing the users with an opportunity to interact with the surrounding environment in a way that would not be possible without the structure in place. He also appreciates how, as an engineer, “you have a lot more flexibility with pedestrian bridges of what you can do in terms of the materials, shapes, and layouts. You essentially have a blank slate of how the structure is going to look, and I find that to be super interesting and super exciting.”
David was integral to the design and engineering of the 23rd Street and 19th Street pedestrian bridges for the University of Colorado Boulder in Boulder, CO. Both projects presented a unique set of challenges in terms of historic and natural preservation, as well as steep rocky terrain. The primary purpose of the two bridges was to connect the campus with other parts of the community, but the project location over a creek and riparian habitat also provided an opportunity to connect bridge commuters with nature. David is proud of the work he and the team delivered but jokingly laments how high the bar has been set for future projects. “Those two bridges have been the main projects I’ve worked on at Otak. They were such interesting projects requiring some innovative design, and have had such a positive outcome for the University and the community. This is the standard I find myself comparing other projects to; it just doesn’t get much cooler than that,” he says.
A current project David is excited to be working on is the Heritage Lid project, which involves parallel vehicular and multi-modal bridges over US Highway 6 (US 6) in Golden, Colorado. US 6 is a major thoroughfare that connects the cities of Boulder and Golden, ultimately meeting I-70 at the base of the mountains. US 6 also bisects Golden, so the new bridges will serve to connect the two sides of the highway. What David finds most interesting about the project is how the bridges are “not just for better vehicular access, but are also meant to provide access for pedestrians and bikers. The focus is on building infrastructure that provides alternatives to getting in a car to drive across a busy intersection, and provides a unique experience along the way.” Although designs are still preliminary, the project will also encompass three pedestrian underpasses, thousands of square feet of wall, and a high level of aesthetics throughout including special features such as landscaping, trees, boulders that kids can climb on, and a shade structure.
David relishes the multidisciplinary team environment at Otak. “Being able to gain the perspective of other professionals and work collaboratively to solve problems and come up with innovative solutions is a real benefit,” he says. “As structural engineers, we’re pretty out-of-the-box thinkers, but working within this ecosystem, and seeing the creative ideas others generate, challenges your own assumptions and constraints about what is possible.”