It’s no wonder Lee County residents are confused about Lake Okeechobee releases.

Half the year, local officials tell them the Caloosahatchee estuaries are dying because they need more freshwater flow from Lake Okeechobee The other six months, they are told the estuaries are dying because there is too much lake water being released.

At the Sept. 21 meeting of the Coalition of Counties for the Responsible Management of Lake Okeechobee, the Caloosahatchee and St. Lucie Estuaries and the Indian River Lagoon, Lee County Commissioner Frank Mann expressed frustration with the public’s lack of understanding of the water quality and quantity issues.

While many Lee County residents have spent much of the summer complaining about the freshwater released from Lake Okeechobee, on Sept. 24 the mayors of the cities of Sanibel, Fort Myers, Fort Myers Beach, Cape Coral and Bonita Springs penned a letter to South Florida Water Management District Governing Board Chairman Federico Fernandez asking for a guaranteed increased flow from the lake during the dry season.

Previously, the dry season flow, measured at the Franklin Lock on the Caloosahatchee River — which is 40 miles from the Moore Haven Lock where water from Lake Okeechobee enters the river — was 300 cubic feet per second (cfs) or about 194 million gallons per day. The South Florida Water Management District recently increased the dry season allocation to 400 cfs.

That’s not enough, say the mayors, who have asked for a minimum flow of 700 cfs, measured at the Franklin Lock.

In the Sept. 24 letter, the mayors argued that the additional freshwater from the lake is necessary to keep the salinity levels in the estuary from getting too high. High salinity is harmful to native plants, such as tape grass, which are critical to the estuary habitat.

The letter cites scientific research which indicates that flows needed for actual restoration of the estuaries could be as high as 1,000 cfs. While the mayors argued for increased lake releases during the dry season, local residents and political candidates seeking the votes of those residents were demanding a halt to lake releases during the summer wet season.

Some of the protesters claim the current lake releases are contrary to the natural flow of the system. But historical records show that before the river was channelized, the Caloosahatchee River received little or no water from the lake during the dry season, and did receive lake flow during the wet season. Before the river was channelized, wet season flooding was common in the towns along the Caloosahatchee, as evidenced by historical photos of water in the downtown streets — and even in the stores — in LaBelle.

Before Hamilton Disston used dynamite and dredges to create a liquid highway from Fort Myers to Lake Okeechobee for freight and human transportation in the late 1880s, the river was connected to the big lake by a series of marshes. During the wet season, the lake would overflow into the marshes at Moore Haven, which has an elevation of around 13 feet above sea level. Water from the lake would flow through from the lake through the marsh to Lake Hicpochee. Water flowed from Lake Hicpochee westward into Lettuce Lake and then Bonnet Lake; when the water was high, the two lakes merged. From Bonnet Lake, water flowed into Lake Flirt, the headwaters of the Caloosahatchee River, near Fort Thompson.

Channelization, first for navigation and later for flood control, changed the hydrology of the Caloosahatchee River watershed, draining that watershed much faster than nature’s design. Today, without artificial flow from Lake Okeechobee during the dry season, the river would suffer from saltwater intrusion. The C-43 reservoir project, currently under construction, would store excess water during the wet season and release it to the Caloosahatchee River during the dry season. But project completion is years away, and the Lee County mayors argue that it will store only enough water to provide 214 days of minimum flows at 400 cfs or 122 days of minimum flows at 700 cfs. Even after the C-43 reservoir is operational, the estuary will still need dry season releases of water from Lake Okeechobee, they argue.

The C-43 reservoir was originally designed in 2008, but the project was delayed when the change of governors brought a change of water management priorities. SFWMD estimates the reservoir will be completed in 2022, at a cost of approximately $500 million.

According to University of Florida studies, about 40 percent of the water in the river comes from Lake Okeechobee. Most of the wet season flow to the river — and most of the nutrient load in the water — comes from local basin runoff.