DESTIN – Tim Pietenpol peered through his sunglasses into the clear water of the south end of Destin Harbor, where scores of small red snapper and other species of fish swam around.

“There’s a lot of sandwiches down there,” Pietenpol, Destin’s deputy director of public services, joked recently.

In fact, it’s not uncommon to see small snapper, Jack Crevalle, sheepshead, trout and other species in the harbor, he said.

Many of them find their way there through the city’s harbor pump system, which includes grating that prevents sea turtles from entering the busy lagoon, city Public Services Director David Campbell said.

The pump system includes a 7-foot diameter concrete pipe that runs under Gulf Shore Drive and connects the harbor-side pump station/discharge weir to an intake box located about 1,000 feet offshore in the Gulf of Mexico.

The pump station and discharge weir stand at 725 Gulf Shore Drive, just west of the Harbor Landing condominiums. This part of the harbor lines up with the Marbella condominiums and Main Street to the north and the Oceania condos and the Gulf to the south.

The pump pulls fresh saltwater in from the Gulf and into the harbor, which is home to the largest commercial charter fishing fleet in Florida as well as hundreds of other types of watercraft. As in past years, the pump could begin working on a daily basis sometime this month.

Duty calls

While the pump is occasionally activated during colder months, it’s on regular duty during the hotter months, or from April until about November.

“That’s when the need for fresh sea water is the greatest for the overall health of the harbor,” Destin spokesman Doug Rainer said.

During the hotter months, more storms and greater stormwater runoff problems challenge the area. These higher-temp months also are when the harbor sees heavier boating activity and when sun-blocking algae and bacteria are more likely to harm fish, plants and other types of marine life.

Regular discharges of Gulf water into the harbor via the pump system increase the harbor water’s clarity, oxygen level and salinity, city officials say.

During the warmer parts of the year the pump runs daily during off-peak hours between 11 p.m. and 7 a.m., when the demand for electricity is lower.

“We don’t receive calls about the noise of the pump,” Rainer said. “We do get some calls from people asking to have the pump turned on during the colder months.”

Destin finished installing the pump system in 1992 at a cost of $3.3 million. The total consisted of $1.8 million in city money and $1.5 million in state funds.

The original system included a carbon steel pump that proved unsuitable for saltwater conditions and needed numerous repairs. That pump, which had a submersible motor, was replaced in 2004 with the existing, stainless steel pump, the motor of which is above water. Destin officials used $450,000 in city money and funding from other sources to pay for the new pump and pump station upgrades.

Before the old pump was replaced, city officials had to send it to its South Florida manufacturer for repairs about every 12 to 18 months, said Maurice Shackleford, owner of Shackleford Construction in Destin. He helped the city install the existing pump.

Campbell said the existing equipment can pump about 50,000 gallons of water per minute. If the pump ran for 12 hours a day, it would take 17 days to replenish, or completely replace, the water in the harbor.

The gates on the discharge weir are always open. That means that even when the pump isn’t running, Gulf water is flowing through, albeit much more slowly, Campbell said.

The quality of the water is the same at both high and low tide, he said.

Diver down

The pipe that runs from the pump station juts out into the Gulf from Holiday Isle. Most people never see the underwater part of the pipe, city officials said. Its southernmost section ends in a massive intake box, the top of which rises 20 feet from the ocean floor and the bottom of which extends 17 feet below the sand.

“It’s a popular dive site,” Campbell said of the box. “It’s been through every hurricane without a problem.”

Pietenpol said city employees who are certified scuba divers remove barnacles and perform other cleanup/maintenance tasks on the intake box and discharge weir as needed, or at least every two years. The pump is inspected monthly.

The annual energy cost of operating the pump is about $20,000 and its annual maintenance cost is roughly $5,000. The annual cost of water testing is about $4,000. That involves testing for dissolved oxygen content, salinity, water clarity, fecal and total coliform (bacteria) and various nutrients. There have been no fish kills in the harbor since the pump system was installed, Destin officials say.