OKEECHOBEE -- They call it “water farming.”

Caulkins Citrus Co., once home to orange groves, is the site of a public-private partnership to reduce harmful freshwater flows to the St. Lucie Estuary.

The 3,200-acre site is adjacent to the C-44 Canal just east of Indiantown. Water from the canal is pumped into bermed reservoirs on the property, where it stays until it evaporates or percolates through the earth into the aquifer. As the water level on the water farm drops naturally, more water can be pumped onto the property.

Additional photos are available at the end of this article.

Thomas Kenny, project manager, explained that the University of North Florida studies the project using a series of wells that were 40 feet, 80 ft. and 180 ft. deep to monitor groundwater. Solar-powered computer equipment constantly collects data. He said they found that 82 percent of the water they put into the reservoir percolates through the earth to recharge the aquifer and 18 percent of the water evaporates.

The site is ideally suited due to the soil composition and the proximity to the C-44 Canal, he said.

“The site is sand, no muck and no hardpan,” he explained. As the water filters through the earth, naturally recharging the aquifer, any excess nutrients in the water — for example, the phosphorus and nitrogen that feed algal blooms — stay on the property, instead of flowing into the St. Lucie River.

All direct rainfall is also captured on site — when it was an orange grove, excess rainfall would drain off through flood control structures.

About 2,800 acres is now covered with water about 4 feet deep.

The property is divided into cells with interconnecting pipes to move the water between the cells. Mr. Kenny explained that the smaller cells are safer than one large reservoir because they reduce the potential pressure on the berms from storm surges.

An added benefit to the local ecology: The property has turned into a natural wildlife preserve, attracting deer, turkeys and a wide variety of water birds. The waterways are filled with fish, alligators, frogs and turtles.

Thick mats of aquatic vegetation cover much of the water surface, helping to clean and purify the water.

According to a SFWMD news release, the public-private partnership between the South Florida Water Management District (SFWMD) and the Caulkins Citrus Co. stores local stormwater runoff and helps reduce the U.S. Army Corps of Engineers’ discharges from Lake Okeechobee to the St. Lucie Estuary.

“Every gallon stored counts during this high water situation,” said SFWMD Governing Board member Brandon Tucker. “The state is doing its part to finish major restoration projects that will store water and protect the estuaries long-term. In the meantime, private landowners like the Caulkins family are stepping up with these public-private partnerships to do their part by giving us the flexibility we need to store water in the short term, helping reduce flows to the estuaries.”

After a two-year pilot project stored more than 40,500 acre-feet of water from the canal and direct rainfall on just 450 acres, SFWMD and Caulkins Citrus formed a public-private partnership to help store water on a much larger scale.

From May 15 to June 22, the Caulkins Water Farm stored more than 5,500 acre-feet of local basin runoff and Lake Okeechobee discharges on top of the 6,000 acre-feet of direct rainfall on the site, keeping that water from flowing into the St. Lucie Estuary.

“This project captured billions of gallons of water in one month and kept it from going into the St. Lucie Estuary,” said George Caulkins III, president of Caulkins Citrus Co. “I think there is a lot of potential in this site and others like it to store local stormwater runoff and protect the St. Lucie Estuary.”