- November 22, 2024
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Two decades after the concept of a roundabout at Gulfstream Avenue and U.S. 41 first appeared in a downtown Sarasota mobility study, the circle replacing one of Sarasota’s busiest intersections is now open to traffic.
Bolstered by a 2008-2010 Bayfront Connectivity Study that recommended roundabouts on U.S. 41 at Gulfstream Avenue and at Fruitville Road, the concept has evolved into a string of roundabouts built or planned on Sarasota's bayfront.
With the opening of the latest and the scheduled spring 2023 completion of the entire intersection project, Sarasota now has roundabouts on U.S. 41 — from north to south — at 14th Street, 10th Street, Fruitville Road and Gulfstream, the latter the vital connector between the mainland and St. Armands, Lido and Longboat keys. Two more at U.S. 41 at Myrtle Road and MLK Jr. Way are in the Florida Department of Transportation design process, and studies and planning for roundabouts at U.S. 41 at Ringling Boulevard and at Main Street are under way.
“The design on those two has been put on hold until funding becomes available,” said Sarasota Chief Transportation Planner Alvimarie Corales of the Ringling and Main roundabouts. “All these have been identified as a transportation priority. It's just going to take a couple of years for them to become implemented. These can take eight to 10 years to see from the top of the priorities list to actual construction.”
According to the Florida Department of Transportation, there are some 20 roundabouts operating on the state highway system — including the four on U.S. 41 in Sarasota — and more than 300 on local roads throughout the state. Growing in popularity, they are not unique to the state, but a network of roundabouts on a short stretch of state highway, Corales said, might be.
“As for a chain of roundabouts, this is the first area that has continuous roundabouts,” Corales said. “At the state level they have seen the benefit of having multiple roundabouts as a chain.”
A chain of roundabouts rather than a standalone facility amid signalized intersections through an urban corridor provides for a more efficient movement, according to Sarasota-Manatee Metropolitan Planning Organization Planning Manager Ryan Brown, who points out that yet another at U.S. 41 and University Parkway is under consideration.
“Traffic studies indicate that a network would improve traffic conditions much more significantly than a standalone roundabout due to the limitations from choke points at signalized intersections,” Brown said. “Signalized intersections are confining, and when you look at implementing a roundabout in the middle of regular intersections with red lights on each side, it’s going to choke.”
Since 2002 the Sarasota/Manatee MPO has had a policy requiring consideration of roundabouts for intersection improvements and in greenfield developments.
“That doesn't mean that they always got full consideration or that they would work in every situation,” said MPO Executive Director David Hutchinson. "Engineers have questioned whether or not they can actually work in rural areas, but in rural areas they actually have proven effective as a safety measure.”
The newest link in the roundabout chain along U.S. 41 is perhaps the city’s most visible. Framed by gleaming towers to the east and Sarasota Bay to the west, it could also be considered among the city’s most scenic — and most complex. It carries U.S. 41 traffic at a 45-degree angle, Gulfstream Avenue to and from the keys and into downtown, a driveway into the busy marina and Bayfront Park, plus nearby entrances into The Quay Sarasota off U.S. 41 as well as Golden Gate Point at the approach to Ringling Bridge.
Maintaining vital traffic through all that during the nearly two years of the project — more than 40,000 vehicles flow through the intersection a day — in addition to installing flood management systems; water, sewer and other utilities infrastructure; and widening the roads approaching and leaving the roundabout was no mean engineering feat.
Further complicating the project were multiple delays caused by supply chain and materials shortages in the wake of COVID-19, and most recently FDOT’s reallocation of resources toward recovery efforts following Hurricane Ian. Heavy rains caused further delay of the scheduled Dec. 17 opening of the circle.
Even with the circle open to vehicles, the overall project, originally scheduled for fall 2022 completion, won’t be done until spring 2023. Remaining is work on lanes approaching and leaving the roundabout, which until now were used as detours around the primary construction site. The true performance of the roundabout won’t be experienced until then.
“Anecdotally, from what we've heard from other MPOs across the country, our initial data is promising from the ones that we've built in terms of resiliency as well as maintaining throughput, which of course is a huge priority for everyone,” Brown said. “Having such large roundabouts in such a dense urban area is something that I think others will look to do.”
That resiliency comes in the form of functionality of intersections during localized or widespread power outages. Roundabouts don’t rely on traffic signals to move traffic.
“You're eliminating the need for vigilance over the signaled systems,” said Nina Venter, multimodal planner of the MPO. “If there's one thing we learned with Hurricane Ian, roundabouts that were otherwise unobstructed continued to function whereas many signalized intersections either lost power or the signals were destroyed. As a resiliency tool, roundabouts are really effective, and at those on 41, which are evacuation routes, are really necessary.”
The essence of the roundabout is to slow down vehicles moving through an intersection while simultaneously speeding up the commute by limiting stops and idling, and increasing capacity. Removing left turn movements in the face of oncoming vehicles eliminates the need for stacking and prevents head-on and T-bone type collisions, when most injuries and fatalities occur. The most common crashes in roundabouts are low-speed rear-ends and sideswipes.
“One of the reasons why roundabouts are so highly advocated for is you don't have to spend the energy of the car to slow down and then speed up, and then also just idle,” Corales said. “You keep the car moving and that requires less energy.”
What makes roundabouts, efficient, especially those with multiple lanes, can also make them confusing to some drivers, particularly those who are unfamiliar with them. Arrows, dotted stripes, solid stripes, dual stripes and flashing crosswalk beacons can be a lot to navigate for a driving culture accustomed to left and right turn lanes, through lanes and signals.
The Gulfstream roundabout may be the busiest in the city with vehicles bound to and from the barrier islands mixing with through traffic at a multi-lane, uniquely shaped circle.
Corales said there will be a learning curve.
“But drivers will see the benefits of it. Gulfstream is large, but as long as you already know roundabouts and how they operate, I think it will be a seamless operation,” Corales said. “Some sections of Gulf Stream have been open for for a while now, so they are experiencing parts of it. Once it’s open, they will experience the whole circle there.”
