The toxic bluegreen algae and phytoplankton blooms that have turned the river and estuary toxic, killed fish, shellfish and decimated critical habitat for manatee, fish, crabs and shrimp this season were the direct result of water management decisions to cut off the Caloosahatchee from water this past fall and spring.
Although the South Florida Water Management District (SFWMD) announced that this drought was projected to be the worst in 50 years, and water shortages were predicted last October, no water restrictions were implemented until March 26.
Now that the rainy season has commenced, it is appropriate to review the water management decisions and their impacts on the Caloosahatchee estuary for this past dry season with the hopes that we can prevent another repeat of these disastrous conditions and get a fair share of public water for the public resources of the Caloosahatchee.
Rains are bringing the first significant water flow to the Caloosahatchee since the U.S. Army Corps of Engineers and SFWMD last cut off all releases to the river and estuary on March 6. The result of being cut off from needed freshwater flow is the exact conditions we warned these agencies about: complete loss of the low salinity zone in the estuary below the W.P. Franklin Lock and Dam and stagnation of water and the toxic bluegreen algae blooms that have polluted nearly half the river the past seven weeks since late May.
Freshwater provides a low salinity zone (SUBHEAD)
Each week since January, we have submitted a report to the Corps and District on Caloosahatchee conditions and warned that without water the estuary’s low salinity zone would disappear and with it the critical habitat for many of our food and recreational fisheries.
Ask the crabbers, ask the snook fisherman, ask the tarpon hunters how their numbers have been and you’ll get the same answer. Devastated. In the lower estuary, 60 to 80 percent of oysters have suffered from disease due to excessively high salinities. These species need freshwater for a portion of their life cycle which coincides with the dry season. So if freshwater to the Caloosahatchee is cut off, sea water from the Gulf of Mexico extends all the way to the lock, eliminating the entire freshwater portion of the estuary below the Franklin dam.
The freshwater tapegrass that supplies refuge, habitat and food for everything from bait fish, juvenile recreational fish fry, shrimp, shellfish and crab larvae to winter feeding grounds for the endangered manatee are killed off by high salinities.
Water flow prevents stagnation (SUBHEAD)
Lack of water flow also deteriorates water quality in the river. Before the 1950s and 1960s, dredging that deepened the Caloosahatchee to its current depth and resulted in the construction of the W.P. Franklin Lock ( S79) in eastern Lee County, freshwater springs provided freshwater flow throughout the year. But today, the springs are gone and low water tables during drought mean that groundwater flow is not available either. Lack of flow causes stagnation that promotes blooms of toxic bluegreen algae that has caused health department warnings to be posted across three counties from the Franklin Lock to Lake Okeechobee.
Ask homeowners along the river what it means to them to have dead fish and clams killed by toxic algae floating and stinking up their backyards making it unbearable to be outside, let alone near the river.
These conditions were preventable with early mandatory conservation and shared cutbacks in water use across all users. Your calls and letters have helped bring this issue to the attention of the agencies but we need to turn that attention to action, changing how the limited water resources are shared and managed. DEP’s response to our letters stated:
“Management of Lake Okeechobee is a matter of balancing flood control, public safety, navigation, water supply and ecological health. The Florida Department of Environmental Protection (DEP) along with the South Florida Water Management District (SFWMD) are fully committed to working with residents, environmental groups, agriculture, governmental agencies and other partners through public processes to evaluate current initiatives and the need for additional actions that will improve water quality and better manage the timing and quantity of freshwater flows to the estuary.”
Ok, but we have not seen the “fully committed” on their part yet. So, let's hold them to action on these commitments. We need the Army Corps of Engineers and SFWMD to re-evaluate the policy and management decisions that cause these unsustainable conditions.
The Caloosahatchee river and estuary are critical to our economy, quality of life and ecological vitality. We cannot allow the failed management of critical natural resources to continue.
Aerial photograph of the Franklin Lock, taken from the north side.