Lake Whistler, Auburndale: The Dam on This Shore Belongs to the Lake Next Door

The district's daily water control structure report gives Lake Arietta an operational range of 140.1 to 143.1 feet NAVD88. Lake Whistler's entire measured range, from August 1984 through September 2026, runs 132.77 to 137.42 feet on the same datum. Arietta's operating floor sits above every level ever recorded on Whistler. What the gate lets go travels down a channel the dam inventory names the P-3 Canal, at a maximum discharge of 200 cubic feet per second.

Published accounts differ on which direction that runs. The Ledger, reporting the 2018 repair, described P-3 as regulating flow from the 75-acre Lake Whistler into the 754-acre Lake Arietta. The agency records put Arietta on the upstream side.

Water that passes the gate does not stop at Whistler. Florida's Department of Environmental Protection, assessing Lake Ariana in 2018, described that 1,030-acre lake as receiving water from Lakes Arietta and Whistler to the north and west, then discharging to Lake Lena through a canal 164 feet long at Ariana's south end. The department's 2015 report on Lake Lena carries the route the rest of the way: Lena's control structure at its southeastern end discharges into Lake Lena Run, which flows into Lake Hancock, and Hancock discharges to lower Saddle Creek, which along with the Peace Creek Drainage Canal makes up the headwaters of the Peace River.

The pipe under the berm was a culvert 42 inches wide and 70 feet long. The Ledger reported that it had been deteriorating over the decades, and that when Hurricane Irma came it started to collapse. The district's account of the damage was the same: during Irma the culvert began to show signs of rusting and started to collapse. On March 27, 2018, the district announced it would replace the rusty steel culvert with a new aluminum one of the same 42-inch width. Patrick Casey, the district's structure operations project manager, said the replacement would match the size of the old one.

Getting to it meant tearing into the berm that residents near Lake Whistler use to reach their homeowners association's boat ramp, and building a temporary dam around the structure to dry out the work area before the old culvert could be dug out. John Dickson, Auburndale's public works director, said the city would temporarily cap a water line running through the project, with no effect on flow to customers. Work began the first week of April and was scheduled to finish before the rainy season, which typically starts June 1. District staff monitored levels on both lakes while it went on.

The dam inventory now lists the condition of Structure P-3 as Satisfactory. In the district's daily water control structure report, the gate still appears under Table 16, the Lake Hancock Drainage Basin summary, and the waterbody named in that row is Lake Arietta.