The new 66.5-acre Gathering Place park, located in Tulsa, Oklahoma, is situated along the Arkansas River and became the largest privately gifted public park in the United States due to its generous $350 million donation from the George Kaiser Family Foundation. Designed by Michael Van Valkenbaugh Associates Inc. (MVVA), it includes seven acres of playgrounds, zip lines, a lodge, nature trails, gardens, a pond, a sports court, concert lawns and more. Originally a flat, windblown and sun-baked site, its topography was altered significantly by raising it in some areas, lowering it in others and reintroducing a broad range of native ecology.
As a way to make the four distinct areas of the park feel cohesive, two sets of land bridges were needed to convey traffic on Riverside Drive. The roadway carries traffic through the bridges and under the park allowing visitors access to the banks of the river and to all areas of the park.
"The bridges increased the amount of park space, and they did it seamlessly, allowing us to grade up on the edges and make the roadway seem invisible as users cross from one side to the other," stated Chris Gates, Associate Principal with MVVA.
HNTB Corp. worked with Contech Engineered Solutions to determine the type of structure best able to bear the weight of high fill, landscaping, and in case of emergency, the city's heaviest fire truck. In addition, it was imperative that the solution be cost effective. Selected as the best solution were two - twin 42' x 11.5' CON/SPAN® O-Series® Bridge Systems, 294' in length. A precast solution was selected over cast-in-place for its cost savings, speed of installation and quality control. After the units were installed via crane, the structures were covered with up to 14 feet of fill at each end of the bridges to form a sight and sound barrier from the traffic below. Each of the structures is wide enough to accommodate two lanes of traffic.
The project included 5,300 tons of precast components, including 196 CON/SPAN arch units weighing 27 tons each. A load was delivered to the site every 30 minutes for a total of 24 loads each day until the project's completion.
"Waterfront space is often isolated by a riverside or lakeside drive," added Ted Zoli, HNTB's National Bridge Chief Engineer. "Putting a deck over a bridge uses landscape to reconnect a city to a waterfront, offering some of the most transformational opportunities in urban design. With the cost-effectiveness of precast arch bridge construction, these spaces can be generous enough to become park spaces on their own. The bridges at Tulsa's Gathering Place are wonderful examples of this strategy."
Inspired by the riverfront location, water became a character-defining element of the park and is included in many play features. Additionally, local natural materials, especially Oklahoma stone was used throughout the park in a variety of ways, connecting the Gathering Place to the region's natural features.
The Gathering Place officially opened in September 2018 and hosted over 300,000 visitors in its first month.
For more information about this project, please read these articles: Roads and Bridges, Informed Infrastructure and Precast Solutions.