Weather permitting, Army Corps of Engineers expects sand placement to be completed late next week
The U.S. Army Corps of Engineers (USACE) issued a contract modification on Thanksgiving Day — Nov. 26 — to the Virginia firm handling the Lido Key Hurricane and Storm Damage Reduction Project, to fill in an area affected by Tropical Storm Eta in November, The Sarasota News Leader has learned.
Following an assessment conducted after Eta passed through the Gulf of Mexico, USACE spokesman David Ruderman told the News Leader that the most significant sand loss on Lido was documented on the southern end of the project area.
Ruderman works out of the USACE’s Jacksonville District Office, which is overseeing the Lido initiative in collaboration with the City of Sarasota.
Cottrell Contracting Corp. of Chesapeake, Va., which began renourishing Lido Beach on July 18, “proceeded right into [the] added work since they had just completed the original contract placement [Thanksgiving] morning,” Ruderman told the News Leaderin a Nov. 30 email.
“They were working on that additional fill area until yesterday when they had to pull the dredge in to safe harbor due to high winds and waves associated with the passing cold front last night,” Ruderman added.
National Weather Service (NWS) data recorded at the Sarasota-Bradenton International Airport showed that just before midnight on Nov. 29, winds began climbing from a range of 7 to 8 mph up to 10 mph and increasing into the early morning hours of Nov. 30. At 7:53 a.m. on Nov. 30, wind was reported out of the west at 25 mph, with a gust at 33 mph.
Gusts of 25 mph and 23 mph were reported earlier, the NWS data show.
Cottrell’s dredge Rockbridge has been removing sand from Big Sarasota Pass, which is between Lido and Siesta keys, to widen Lido Beach.
As of Nov. 30, Ruderman noted in his email, “[I]t looks like they will resume dredging around Wednesday or Thursday of this week and may complete the modification work within a week from then, weather permitting. That will be the final beach fill for this project and the dredge will be demobilized after that.”
A subcontractor is scheduled to construct two groins on the southern portion of the beach to try to hold the sand in place between subsequent renourishments, which are anticipated approximately every five years, according to documents provided to the Florida Department of Environmental Protection (FDEP).
The groin work on the beach is expected to start in January 2021, Ruderman told the News Leader in mid-November.
No documented issues with turbidity in Big Pass
The News Leader also took the opportunity this week to review the latest sets of turbidity monitoring reports related to the dredging in Big Pass. Under the terms of the FDEP permit for the Lido project, personnel have been assigned to the Cottrell Contracting dredge to ensure that removal of sand from the pass does not result in persistent cloudiness in the water, which could be detrimental to sea life that relies on sunlight to survive.
The first of those recent reports, issued on Nov. 13, noted that the dredge was shut down following the passage of Tropical Storm Eta. Nov. 11 was the primary day Sarasota County residents experienced the effects of the storm, with rainfall of more than 6 inches in some areas and wind gusts in the mid-40 mph range.
The first report on Nov. 14 — issued at 7 a.m. — noted that adjustments were being made to the pipeline used to transfer the sand to the shore, and maintenance was underway on the “cutterhead,” which is the equipment used to bore into the sand borrow areas. Just after 3 p.m. that day, the dredging had started, a later report said.
At 7 a.m. and 11 a.m. on Nov. 16, the turbidity reports pointed out, the dredge was not operating because of mechanical issues. Finally, by midafternoon that day, the sand removal once more was underway.
Mechanical issues have been noted in a number of the turbidity reports over the past months.
The Nov. 26 reports — the latest available prior to the News Leader’s publication deadline this week — showed no issues with the dredge or turbidity.
The wind on the afternoon of Nov. 26 was out of the southwest at a maximum of 10 knots, according to the reports issued at 3:03 p.m. and 3:15 p.m.
A report completed at 11:12 a.m. on Nov. 26 noted that the wind was blowing a maximum of 8 knots out of the southeast, an increase from the 4-knot speed recorded in the 7 a.m. report.
The previous day — Nov. 25 — the wind was out of the east when dredging was underway just after 7:35 a.m. However, the 11:09 a.m. report put the maximum wind speed at 16 knots, out of the southeast. Still, that report also indicated that the seas were calm.