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The Caloosahatchee Goldlilocks Condition
Record setting rainfall the last 2 weeks of May flooded the entire Greater Everglades region. To manage lake water levels, the Corps of Engineers began Lake Okeechobee releases on June 1st to the Caloosahatchee and St Lucie estuaries. The Caloosahatchee received harmful estuary flows 2 to 3 times harmful volumes. In a matter of days the Caloosahatchee flipped from 3 months of harm caused by too little freshwater, to harm from too much freshwater. This increasingly frequent condition is what prompted me to coin the description The Caloosahatchee Goldilocks Condition in 2004.
Generally high flows are directly related to high rainfall combined with the loss of storage capacity in the ditched and drained greater Everglades ecosystem but this sudden event, that started with early rainfall at the very beginning of the wet season, bears greater scrutiny because, frankly, it was unnecessary and the direct consequence of bad water management decisions.
Following Hurricane Irma in September 2017 the estuary was blasted with high flows through December. Within 30 days, despite lake levels remaining harmfully high, water managers decided to cut back needed lake flows to the Caloosahatchee, causing salinity levels to creep upriver to levels that exceeded the minimum flow and level harm standard of 10 psu at Fort Myers. For three months, despite our requests and clear evidence that there was sufficient water in the lake to meet all agricultural and other water supply demands and maintain healthy salinity levels in the Caloosahatchee, even if the rainy season started near the end of June, they refused. So the Caloosahatchee got too little freshwater, harming struggling freshwater tapegrass habitat in the upper Caloosahatchee.
Then it started to rain in mid-May. For two weeks the Caloosahatchee got harmful levels of water just from our rivers watershed — runoff from Hendry and Glades Counties — with no discharges from Lake Okeechobee. Harmful high flows that cause low salinity impacts to estuarine and marine organisms occur when freshwater flows at the Franklin lock reach 2,800 cfs (1.26 million gallons/minute or 1.81 trillion gallons/day).
On June 1st, very high discharges from Lake Okeechobee were dumped west that nearly tripled the harmful high flows to the estuary, (over 3.68 million gallons/minute or 5.3 trillion gallons/day) dumping dark fresh water and suddenly dropping salinities in the estuary all the way to the mouth of the river at Shell Point.
The consequence of this sudden, drastic and continuing salinity drop has been a massive die off of estuarine clams and oysters at Iona just upstream of Shell Pointe and is fueling harmful freshwater cyanobacteria, including Microcystis from LaBelle to Iona Cove.
So although the lake, estuaries, and southern Everglades ecosystems were all flooded with too much water, the farmlands in the EAA south of the lake got ideal flood control and water supply conditions. Beginning with the first week water was dumped to the coasts, 98.5% of that discharge was backflowed water from the L8 Canal on the east coast and the Clewiston Industrial canal on the southwest side of the lake! Water comes into the lake six times faster than it can be discharged, so with the lake a harmfully high levels at the very beginning of the wet season, it makes no sense to allow agriculture to shunt their stormwater into the lake where it then gets dumped on the estuaries that have also received too much rain.
On June 20, the Governor directed DEP to issue an emergency order to the Army Corps urging them to temporarily modify permitted operations in order to move water south out of Lake Okeechobee. The order expires on November 30, 2018.
Solutions
The operational protocols for operating this system must change, especially as we face more extremes in weather variability. The past few years, records have been broken for droughts and deluge in the 86 years of record keeping.
1. If the agricultural backflows into the lake had not been allowed there would not have been a need to make the massive, early season estuary discharges. The backflows accounted for 98.5% of the water discharged to the estuaries.
2. It was premature to dump massive quantities of water to the estuaries at the very beginning of the rainy season when no water was being held by or discharged to agricultural areas to share the harm. There was capacity in the lake for this early event.
3. EAA stormwater has usurped and consumes nearly all the capacity of the taxpayer funded stormwater water treatment areas (STAs) and Water Conservation Areas (WCAs) storage capacity south of the lake. This infrastructure was designed to take water from Lake Okeechobee, not serve as agriculture’s personal storage.
4. If water managers had not starved the Caloosahatchee of needed freshwater flows for the four previous dry months, the lower lake would have had even more capacity to store water.
Our estuaries cannot afford to bear the burden of agriculture’s preferential treatment for stormwater and water supply. Common complaints by agriculture that blame the Cape Sable Seaside Sparrow for their water woes are a ludicrous diversionary tactic to keep the public from recognizing the multitude of ways the agencies operate the hydrologic system for the selective benefit of EAA agriculture south of the lake.
The agencies are not going to change the protocols unless we demand it. It is past time to change the system. Progress has been made over the past 24 years I’ve been engaged in this fight. Several projects to open up flow through the bottom of the Everglades system are coming on line this year and next. It takes time but the outcomes are within our reach. Stay connected and stay engaged, in this fight ever voice counts.