Investigating the Causes and Mitigation of Harm Algal Blooms, Including Red Tide, in South Flor William J. Mitsch, Ph.D.

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1 Investigating the Causes and Mitigation of Harm Algal Blooms, Including Red Tide, in South Flor William J. Mitsch, Ph.D. Eminent Scholar, Endowed Chair, and Director, Everglades Wetland Research Park, Florida Gulf Coast University Courtesy Professor, School of GeoSciences, University of South Florid Professor Emeritus of Environmental Science, The Ohio State Universit

2 Presentation Outline Harmful Algal Blooms in the World Everglades Restoration, Lake Okeechobee and Water Quality Issues in South Florida Recent Red Tide Investigations in Ft. Myers area Isotopic Analysis to Identify Sources of Nitrogen Pollution What It s Going to Take to Fix All of This Conclusions

3 More than 750 aquatic ecosystems worldwide currently suffer from degraded conditions due to urban and agricultural inflows that cause water quality degradation often referred to as hypoxic or harmful algal blooms due to nitrogen and phosphorus Source: World Resource Institute

4 Restoring the Florida Everglades Source: Mitsch and Gosselink, 2015

5 Coastal Water Pollution in Southwest Florida Caloosahatchee River 2016 Gulf of Mexico Sanibel Island An unseasonable amount of precipitation (>30 cm) fell on south Florida in the dry season in January 2016 due to extensive frontal storms caused by El Nino. Approximately 3.1 billion m 3 of polluted Lake Okeechobee (Lake O) water was sent down the Caloosahatchee River to the Gulf of Mexico and the St. Lucie Canal to the Atlantic Ocean in 2016, severely polluting both estuaries. The pumping of water to these outlets was deemed necessary because of high and unsafe Lake Okeechobee water levels, which were, in turn, due to the high rainfall events in January 2016.

6 Five months later in 2016 the Florida governor declares a state of emergency for both coastlines over 'guacamole-thick' blue-green algal blooms in coastal waters.

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8 Red tide in SW Florida (August 2018)

9 Red tide sampling in SW Florida (August 8-9, 2018)

10 Once again, in August 2018, the Florida governor has declared a state of emergency for Florida, this time for two distinct harmful algal blooms: 1. blue-green freshwater HABs and 2. red tide saltwater HABs

11 Red tide sampling locations, Ft. Myers coastline, August 8-9, 2018

12 Red tide water quality and Karenia brevis counts, Ft. Myers coastline Aug 2018

13 Karenia brevis counts August 8-9, 2018

14 Isotopic analysis of Lake Okeechobee and Gulf of Mexico Isotopic analysis of nitrogen compounds has proveen to be a viable tool to identify sources of nitrogen pollution and the processes affecting nitrogen both in surface and groundwater. Different sources of nitrate can have distinct isotopic ( 15 N-NO 3 and 18 O-NO 3 signatures).

15 Nitrogen data from Pei Ma, Ph.D., visiting scientist at Everglades Wetland Research Park, FGCU

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17 Solutions to all of these HABs in south Florida

18 New Everglades Agricultural Area (EAA) Reservoir Proposal Flow south to the Everglades from Lake Okeechobee will increase by 76% from 210,000 to 370,000 acre-ft/yr. A 240,000 acre-foot reservoir (23 ft deep and 10,100 acres in area) will be built for water storage. Only 6,550 acres of treatment wetlands (13% increase) are proposed. As designed, this EAA Reservoir project will likely deliver phosphoruscontaminated water to the Florida Everglades.

19 Treatment Wetlands in the Everglades aka Stormwater Treatment Area (STA s) Lake Okeechobee Everglades Agricultural Area Florida Everglades Stormwater Treatment Areas (light green) 57,000 acres of these wetlands have been created. Source: SFWMD

20 Stormwater Treatment Areas (STAs) upstream of Everglades

21 Annual flow and inflow and outflow phosphorus concentrations in treatment wetlands (STAs) in northern Everglades designed to reduce phosphorus from agricultural runoff In 2015 Inflow P: 99 ppb Outflow P: 17 ppb 10 ppb Source: SFWMD 2016 report

22 Conclusions Red tide is and has been a natural phenomenon but it is clear that human activities, principally high-fertilizer agriculture, bears some of the responsibility for giving natural red tide a booster shot. Wetlands can be designed to remove significant amounts of nitrogen and phosphorus from agricultural and storm water runoff and are significant sinks of atmospheric carbon as well to mitigate climate changes. Concentrations on the order of ppb of total phosphorus and 1 ppm total N are reasonable expectations but lower concentrations can be achieved from treatment wetlands in Florida.

23 Conclusions In the Florida Everglades, the pollution of the east and west coastal estuaries by Lake Okeechobee water has to stop and the original north to south flow of the greater Everglades must be achieved, but only with clean water. The current EAA reservoir plan is inadequate in its guarantee to deliver clean water to the Florida Everglades. Florida needs to install 100,000 more acres of treatment wetlands in the 700,000-acre EAA, 14 times more than is currently included in the current EAA reservoir plan, to insure clean water to the Everglades and subsequent reduction of Lake O discharges to coastal waters. Wetland restoration and creation are not easy. They require attention to Mother Nature (self-design) and Father Time (projects take time to reach their potential).

24 Thank you!