Design Services for Roundabout at US 98 from South to North of Trilby Road

Pasco County, FL

This task was initiated by FDOT District 7 Traffic Safety Office in response to a continued trend of severe angle and left-turn crashes in addition to the focus on Vision Zero safety solutions. These severe crashes resulted in three fatalities and 14 injury crashes between 2012 and 2017. As a result, FDOT explored treatments to enhance the safety of this rural, high-speed intersection with stop-controlled side streets. After an Intersection Control Evaluation (ICE), a roundabout was selected as the preferred countermeasure, although right of way was a severe limitation since any property acquisition would extend the project duration by two to three years.

FDOT selected ELEMENT to complete the survey and design, targeting an accelerated 10-month design process so available Highway Safety Improvement Program funds could be used for construction. Video count data was acquired at the project intersection to determine the specific design and control vehicles to be used on this key freight corridor with 22 percent trucks. Throughout the design process, the ELEMENT actively coordinated with key project stakeholders, provided iterative design solutions to meet the applicable design guidelines while avoiding any right of way impacts, and expedited the various design services and utility coordination to deliver the final design in 10 months. Additionally, to maintain access to local businesses and residences as well as maintain the high truck traffic through the corridor, a nine-phase temporary traffic control plan was developed to meet these goals and the overall restriction of full road closures of US 98 not being permitted. To enhance safety within the work zone, the maintenance of traffic plan incorporated a pilot study for active and passive speed management devices in conjunction with staff from the Center for Urban Transportation Research at the University of South Florida.

The construction contract was awarded on December 26, 2019 with construction of the roundabout completed on October 6, 2020. The roundabout is expected to have a benefit to society of $28.9 million due to an anticipated 83 percent reduction in all crash types. Stakeholders, including Pasco County, elected officials, and FDOT staff have applauded the completed project and the immediate enhancement to the safety both at the intersection and in the immediate area due to the reduced operating speeds along the corridor.