Sarasota County begins shoreline work at Nathan Benderson Park

Sarasota County has begun a $517,803 Shoreline Stabilization Project at Nathan Benderson Park. The work will repair damage done in 2017 by Hurricane Irma.

Nicole Rissler, the director of Parks, Recreation and Natural Resources for Sarasota County, said the damage to the southern shoreline of the park's main lake amounted to wave damage. The length of the 3.6-mile lake allowed waves to gain significant force during the hurricane to do the damage.

She said regular storms have not had the impact that Hurricane Irma possessed and therefore have not been caused any similar damage at the park.

“It was an extraordinary event with the hurricane,” she said.

The waves caused erosion to the south shore, as well as to the boat launch platform, only weeks before the World Rowing Championships. As a result, Sarasota County performed emergency repairs that included the shoring up of material beneath the start line abutments.

Rissler said, however, that from a long-term standpoint, the staff has been working on the current project, which will offer shoring up and stabilization at the south end of the lake, as well as fixing erosion underneath a section of sidewalk.

She said the current project had to be timed around many of the major events in the park and could not be started until now.

Rissler said repairs are concentrated strictly in the southwest and southeast corners of the lake, while the shoreline between those areas was determined to have suffered damage merely on an aesthetic level.

Approximately 275 feet of sidewalk will be removed in order to have the sub-base replaced, and will then be reconstructed.

Rissler emphasized the sidewalk that will be repaired is not the pathway around the park, but exists specifically to connect the start line to the wave attenuator, the long dock which extends into the water in order to break up waves. Rissler said the sidewalk at the area of the attenuator has been closed since 2017.

Rerouting will take place for the adjacent pedestrian and bike paths. Pedestrians will be redirected along the south end of the lake.

A temporary sidewalk will be provided along World Championship Drive, which runs along the southern end of the lake and along its east side. Pedestrian and vehicular traffic will be separated by traffic barrels.

Rissler said for most of the project, park users will still be able to access the southern area. Brianne Grant, a public information officer for Sarasota County, said park visitors will notice signage and digital message boards near closed-off areas.

Rissler said new riprap comprised of limestone rocks, along with sheet pilings, will be placed along the shoreline, and will help resolve the erosion issue.

Brianne Grant, a public information officer for Sarasota County, said the riprap will be around the same size as the material already around the lake, with the rocks weighing 40 to 80 pounds and measuring between 8 and 14 inches in diameter.

She said staff will create a footer at the bottom of the riprap shelf where they will place a geotextile sheet, a type of sheeting designed to increase soil stability.

This sheet is composed of high-tenacity fibers made of polypropylene. Grant said it these are resistant to biological degradation, including chemicals found in the natural environment such as alkalis and acids.

Riprap material will be transported from a staging site, to the project site, using a small loader or skid steer. It will be placed into the lake area by a long-reach excavator, before staff move the rocks around by hand to ensure they properly lock into place. 

During construction, a floating barrier known as a turbidity barrier will be placed in the lake to prevent the flow of sediment contamination from the construction site.

Rissler said the project will also replace the material underneath the sidewalk. Although erosion is not visible from the ground area, Rissler said it has been detected beneath the sidewalk.

“If you look at it with the regular eye, you would think there's nothing wrong with it,” she said.

The boat ramp is also set for repairs.

Rissler said it was also damaged by the forces of erosion from the storm.

“The surface is smoother than we would like for a boat ramp,” she said, explaining that more traction is desired for boat users.

The ramp is different from the launch point normally used in community events, and is primarily recreational in use.

She said in that same corner, shoring up will also take place, with riprap and sheet metal once again being inserted into the water to help stabilize the shoreline.

Rissler said the new additions are expected to help absorb the wave action in the case that any storm activity takes place at Benderson again, and she emphasized that she does not expect the park to see similar damage in the future.

“We’ve had lots of storms,” she said. “We’ve had lots of tropical storms. We’ve had lots of winds since 2017. I think it was, no pun intended, a perfect storm — that wind and where it came out of.”

It is estimated that the project will involve the southwest corner until Aug. 26, the southwestern corner and boat ramp from Aug. 29 to Oct. 14, and the project wrap-up and site restoration from Oct. 15 to Nov. 15.

According to the Nathan Benderson Park Conservancy, fishing in the west part of the lake will be unaffected by the shoreline project. Canoes and kayaks can be used for fishing, and can be launched from Regatta Island and the west shore along World Championship Drive. Both rod-and-reel and cast-net fishing are allowed.