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LOSOM: An Opportunity to Improve Florida Water Policy

Contextual history of Florida's drainage followed by a regularly updated analysis on the status of LOSOM both procedurally and substantively.
LOSOM: An Opportunity to Improve Florida Water Policy
Sunset over a central Florida watershed leading into the northern Glades. 

The Army Corp of Engineers is in the midst of developing a water management plan that will govern freshwater releases from Lake Okeechobee, and replace the Lake Okeechobee Regulation Schedule from 2008, called the Lake Okeechobee System Operating Manual (“LOSOM”).¹ This post gives a brief historical overview of Florida’s drainage and development in order to contextualize the importance of LOSOM and its impact on Florida’s coastal and Everglades (“Glades”) ecosystems, followed by a running and frequently updated analysis on where matters currently stand with LOSOM both procedurally and substantively.

A central issue modernized Florida faces is too much water during the wet season and not enough water during the dry season.2 As detailed below, this broad issue relates to algal blooms that are destructive to eastern and western coastal estuaries during the wet season and a lack of fresh water needed to sustain the southern Glades during the dry season. Fortunately, there is a Comprehensive Everglades Restoration Plan (“CERP”), which is a 50/50 partnership between the federal government, through its Army Corp of Engineers (“Army Corp”), and the state of Florida, through its South Florida Water Management District (“SFWMD”), designed to address these issues.³ CERP, authorized by Congress in 2000, relates to LOSOM as discussed below.⁴

First, some background information and history is necessary for context. It is generally understood that Lake Okeechobee (“Lake O” or the “Lake”), about a hundred miles north of Everglades National Park, is the heart of the Glades, and sources most of its water from its northern watershed, the Kissimmee chain of lakes, which extends almost as far north as Orlando.⁵ In its natural form, water would spill over Lake O’s southern banks, expanding laterally and inching south in the form of a shallow, slow-moving sheet flow of fresh water that would push down hundreds of miles, contributing to the brackish water in and around Everglades National Park and continue further south into Florida Bay, where the Gulf arches alongside the Florida Keys.6  As such, this was and is to an extent an interconnected system.

In the late 1800s, agriculture was a distant but sought after goal for central Florida lands.7 Expensive waterfront properties on what is today called “improved” land (land that has been developed and is occupied by buildings and structures) were not yet within the realm of possibility.8  Draining Florida’s naturally flooded lands to “reclaim” (make a desert, wetland, or other unusable land suitable for development or farming) the land was the number one task and obstacle to human development and conquering what was generally thought of as a harsh and useless wasteland.⁹ After a dramatic series of failed attempts at drainage, Lake O was artificially connected to the St. Lucie and Caloosahatchee rivers, which were connected to canals, deepened, widened, and straightened as needed to facilitate large-scale drainage.10 The brackish water in the coastal estuaries at the mouths of these rivers remain some of the most productive ecosystems in the world,11 and their health has extensive implications for Florida’s marine ecosystems as their waters push to sea and are often visible up and down both coasts and for many miles offshore.

Early settlers south of Lake O constructed small embankments around the lake around 1915, but major hurricanes in the 1920’s created massive storm surges that swept over the embankments and killed over 2,500 people.12 This period of flooding spurred President Herbert Hoover to get the federal government involved in building levees around the Lake in the 1930’s.13 After another significant hurricane landed in 1947, Congress passed the Flood Control Act of 1948, authorizing the Central and South Florida Project (“C&SF”).14 C&SF involved the construction of an elaborate system of roads, canals, levees, and water-control structures stretching throughout South Florida.15 By the late 1960’s, Lake O would be nearly completely surrounded by a substantial dike system called the Herbert Hoover Dike.16 Every cubic foot of water that leaves Lake O’s confines has since been directed and managed by the federal government (other than through Fisheating Creek, which is the Lake’s last free flowing creek comprising a small mid-western section of the Lake17) through the Army Corp. The Army Corp remains in charge of scheduling when and where Lake O’s waters are sent to this day.18

It is plain to see why the Glades would need more water sent south from Lake O, in accordance with the natural hydrologic system that was in place for roughly six thousand years before it was altered and in many places severed in the last roughly 130 years.19 Part of the problem is that the Glades need more water south generally. However, circumstances have changed, as there are competing interests for limited water in the dry season and swathes of development and agriculture within the hydrologic flow way, with roughly 50% of the Glades even remaining.20 Additionally, the hydrology of the Caloosahatchee River (the “Caloosahatchee”) was changed so significantly in the late 1800s when it was deepened and widened and connected to Lake O that it now actually requires low volume freshwater releases from Lake O during the dry season to counteract saltwater intrusion and support its ecology.21 These factors create year round complications on how to manage the Lake, during both the wet and dry season.

The land comprising over 700,000 acres immediately south of the Lake is called the Everglades Agricultural Area (“EAA”), and not surprisingly, the EAA is mostly farmlands, with sugar companies controlling roughly 500,000 acres.22 Extensive political history aside, it is not controversial that the agricultural interest is mainly in ensuring year round irrigation, while sending water south in accordance with natural hydrology is crucial to sustaining the southern Glades. As such, there are direct competing interests over where the Lake water goes during the dry season. Further, incentives do not align on what depth to keep the Lake at any given time and how to develop reservoirs and basins that can store additional Lake water per CERP and related plans.23

The wet season is the time to store water for the dry season, while the tail end of the dry season is a time to distribute water to the extent possible in preparation for an influx of water in the wet season.24 This is a constant balancing act. During the wet season, all parties’ immediate water needs are met by an excessive amount of rain, which creates other issues.25 When Lake O levels are high during the wet season, the excess water in combination with nutrient-runoff in the Lake’s watershed creates conditions ripe for blue-green algae blooms in unnatural proportions that are generally detrimental to ecosystems.26 Further, when the Lake level reaches high levels, it becomes a flood risk and poses a safety hazard to local communities if a hurricane were to come along, and it is generally bad for the Lake’s ecology, as submerged plants do not get enough sunlight.27 Of course, south Florida communities also depend on underground aquifers south of the Lake for water supply purposes.28

The question arises as to when and where to send water during the wet season, considering all factors. A general solution is to get the water clean and send it south in accordance with the natural system.29 However, sending the water south requires sending it through the EAA, down through the Stormwater Treatment Areas (“STAs”) which are essentially man-made wetlands designed to filter excess nutrients out of the water, further down through the Water Conservation Areas (“WCAs”), at which point the water will reach relevant Wildlife Management Areas (“WMAs”) and other conservation lands, down to Everglades National Park, and finally out to Florida Bay.30 This multifaceted pathway south, not as expansive or free flowing as it once was, gets saturated and full during the wet season based on standards set forth in regulation schedules, and at a certain point, historically, there has been nowhere for the Army Corp to send the additional Lake water except out through the Caloosahatchee and St. Lucie rivers, regardless of whether the Lake water will negatively impact salinity levels or damage the estuaries.31

These are somewhat complex issues. However, CERP projects involving land acquisition, additional reservoirs to store water, and additional STAs to clean and convey water are and have been underway.32 The Army Corp has worked extensively with the state, mainly through SFWMD to address these issues and enact CERP plans, of which there are over 50.33 One high profile example is the Everglades Agricultural Area Reservoir Project (“EAA Reservoir Project”), which includes a treatment wetland that will clean water and a reservoir that will store excess Lake water.34 SFWMD, responsible for constructing the 6,500-acre STA, began construction ahead of schedule in 2020 and plans to complete it in 2023.35 The Army Corp is building the reservoir component, which will hold 240,000 acre-feet of water.36

It is against this backdrop that the Army Corp is now developing LOSOM, in part to account for progress made under CERP plans and infrastructure improvements (though it will have to be revised to account for the EAA Reservoir specifically, as it is incomplete).37 LOSOM will determine what specific schedule the Army Corp follows in determining when, to where, and roughly how much water flows from Lake O.38 Unpredictable factors such as hurricanes require a level of flexibility, but LOSOM will contain guidelines with optimal ranges of seasonal water flows.39 The conceptual goal of LOSOM is to create a more balanced water management plan for all stakeholders.40

LOSOM has been in development since early 2019, with many public meetings and opportunities to provide feedback.41 Substantive work began with the development of conceptual plans, in which the Army Corp “simulat[ed] ~120,000 variations of conceptual schedules using a subset of sensitive and representative criteria to guide the analysis.”42 During “Iteration 1” of the process, eight single-objective plans were developed, in which models focused specifically on algal bloom risk, navigation, recreation, water supply, and the ecology of the major individual water bodies.43 The goal of Iteration 1 was not to pick a plan, but to see what worked.44

Next, during Iteration 2, elements of the single-objective plans were combined, modified and narrowed down to six, more balanced, plans (AA, BB, CC, DD, EE1 and EE2) that varied in performance across different metrics.45 These plans were scored against a no-change alternative based on their impact on Lake Okeechobee, navigation, recreation, ecology of both the St. Lucie and Caloosahatchee estuaries, algal bloom risk in both the St. Lucie and Caloosahatchee estuaries, south Florida ecology generally, and water supply for each of the Seminole Tribe of Florida, Lake Okeechobee Service Area, and Lower East Coast Service Area.46

Among conservation non-profit organizations, the general consensus was in support of Plan CC, subject to revision and optimization during Iteration 3.47 However, the consensus was also that Plan CC was unacceptably harmful to the Caloosahatchee’s ecology.48

As part of Iteration 2, the Army Corp selected Plan CC as its starting point and conducted a roadshow designed to hear feedback as to how various stakeholders wanted to see Plan CC optimized, or revised, during Iteration 3.49 The chart immediately below,50 showing Plan CC pre-optimization, is now outdated but demonstrates how much of an impact stakeholder comments had on the optimization process.

Modeling for Plan CC prior to optimization (pre-November 16, 2021)51

The vertical axis shows the water level, measured at a listed lock and dam in each respective river. The relevant locks and dams are listed in the outside columns of arrows, which show allowable flows to each river, depending on water level and the time of year, shown on the horizontal axis. Each Zone is comprised of the area between its respective line and the line for the Zone above it (except Zone A does not have an upper limit). In sum, the Zones demonstrate a range of releases allowable to the estuaries depending on water levels of the rivers’ locks and dams and the time of year. The pink arrow demonstrates releases south could occur when the Lake level is above 13 feet. The chart also notes that when Lake levels fall into the Water Shortage Management Band (ranging from 10.5-13 feet),52 releases are determined by the State of Florida, and that when water levels are extremely high (roughly 17 feet), maximum releases are allowable.

Flows to the Caloosahatchee are measured at two different locks, the S-77 Moore Haven Lock by the Lake and the S-79 Franklin Lock by the estuary. On the other hand, as seen above, flows to the St. Lucie are measured only at the S-80 lock by its estuary. Naturally, measurements of water level at the estuary factor in watershed runoff from upstream, while measurements by the Lake upstream do not. As such, by measuring the water level near the Lake, Plan CC under-represents how much water the Caloosahatchee estuary is authorized to receive.

Stakeholders raised issues with pre-optimized Plan CC, mainly centering on the high volume of allowable flows, measured in cubic feet per second (“cfs”), to the Caloosahatchee.53 Stakeholders advocated for flows within the Optimal Flow Envelope (which was 750–2100 cfs in 2020), especially in Zone D, likely to be the most prominent zone,54 and also in Zones B and C, which allowed for releases up to 7,200 cfs. Stakeholders also called to remove Zone F, allowing more beneficial dry season releases to the Caloosahatchee55 and to consider and improve upon modeling done by SFWMD.56

On November 16, the Army Corp released the optimized model run (the "Optimized Model")57 on which the substantive drafting of the LOSOM Lake Regulation Schedule, Water Control Plan, and Environmental Impact Statement will be based:

Substantive LOSOM drafting will be based on this Optimized Model.58

This Optimized Model is the most recent substantive development on LOSOM and is noticeably different than pre-optimized Plan CC. The most prominent improvement in the Optimized Model is to Zone D, where the Lake is expected to sit about 76% of the time.59 Up to roughly 17 feet, the Final Model does not allow more than 2,000 cfs of releases to the Caloosahatchee and allows none to the St. Lucie. Zone F from the pre-optimized Plan was also removed, facilitating low volume beneficial flows to the Caloosahatchee. Flows south to the Everglades are also authorized at significantly lower Lake levels than in pre-optimization Plan CC. These are major successes.

Note, however, that the Optimized Model allows high and even unlimited volume flows when the Lake level is high enough in Zones A-C and is not much of a change in this regard. The Lake is expected to be in Zones A-C roughly 4.7% of the time, during which these high volume releases are allowed.60 However, these expectations are mere estimates and do not consider the quantity of times the Lake level enters into a particular Zone.

As such, the Optimized Model does not in and of itself guarantee no problematic freshwater releases, and conditions are expected to worsen as to the Lake's ecology.61 The Army Corp has indicated on many occasions that any improvement requires a tradeoff. However, the Army Corp's comments are understandably based off of its limited scope in modeling tradeoffs between stakeholders while it develops LOSOM. Land acquisition, restoration projects, and local government laws are a few examples of other factors that may play a role in the Lake's ecology and restoration generally. It is important to note that the Army Corp's modeling is only one factor affecting Everglades and coastal restoration and ecology.

There seems to be a misunderstanding among media outlets that the LOSOM process is over and that harmful discharges are being reduced by a finite percentage. This is not true.

The Army Corp has stated that it still needs to "merge [the] selected model run with all of the other feedback and lessons learned."62 As such, the Optimized Model is not actually final. Further, once this vague merging is done, substantive drafting will finally begin on the actual Lake Regulation Schedule, Water Control Plan, and Environmental Impact Statement.63

The Record of Decision marking the conclusion of the LOSOM process is not projected to be approved until 2023 after the above mentioned documents are revised and commented on extensively.64  As such, no one has the ability to tell what percentage of discharges will be reduced in the coming years, because that depends on what Zone the Lake will be at years down the road. There are also no guarantees the Optimized Model will not change.

So, LOSOM is not and should not be considered finalized until the actual drafting is completed. The Optimized Model does sound promising, but the LOSOM process is not over, and it is not a time for complacency.

Having said that, the Optimized Model seems to be a major improvement over the pre-optimized Plan CC and existing Lake Okeechobee Regulation Schedule from 2008. It should be supported as such. GHL commends the Army Corp, SFWMD, and other stakeholders for their diligent effort in getting to this point in the process.

The final slide In the Army Corp's November 16, 2021 slideshow presentation.66

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Table of Citations

¹Lake Okeechobee Systems Operating Manual: LOSOM Facts and Information, U.S. Army Corp of Engineers (2021).

²Flood Control, South Florida Water Management District (2021).

3-4Restoration Plan: CERP, U.S. Army Corp of Engineers (2018).

5-6Lake Okeechobee, South Florida Water Management District (2021).

7The Swamp: The Everglades, Florida, and the Politics of Paradise, Michael Grunwald (2006).

Improved Land, Black's Law Dictionary (11th ed. 2019).

Reclaim, Black's Law Dictionary (11th ed. 2019).

10Caloosahatchee River and Estuary, South Florida Water Management District (2021); Focus on the St. Lucie River, South Florida Water Management District (1999); The Swamp: The Everglades, Florida, and the Politics of Paradise, supra.

11Life in an Estuary, National Oceanic and Atmospheric Administration (2019).

12-14About Herbert Hoover Dike, U.S. Army Corp of Engineers (2021).

15 Development in the Everglades, National Park Service (2015).

16About Herbert Hoover Dike, supra.

17Fisheating Creek - Habitat and Management, Florida Fish and Wildlife Conservation Commission (2021).

18Just the Facts: Lake Okeechobee Coastal Releases, South Florida Water Management District (2021).

19Lake Okeechobee… Fish, Floods, and Farms, South Florida Water Management District (2021).

20Everglades, South Florida Water Management District (2021).

21USACE Increases Lake Okeechobee Releases to Caloosahatchee, U.S. Army Corp of Engineers (2021).

22Central and Southern Florida Project Comprehensive Review Study, South Florida Water Management District (1999).

23Lake O Discharges: Sugar Farmers Sue Army Corps over EAA Reservoir: Will it Delay Project?, Ed Killer, Treasure Coast Newspapers (August 27, 2021).

24SFWMD Prepared for Wet Season, South Florida Water Management District (2018); Dry Season and Drought Are Not the Same, Abbey Tyrna, University of Florida Institute of Food and Agriculture (2021).

25District Remains Laser Focused on Sending Water South, South Florida Water Management District (2020).

26Addressing Blue-Green Algal Blooms, South Florida Water Management District (2021).

27Cyanobacteria in Florida Waters, Florida Fish and Wildlife Conservation Commission (2021).

28Florida’s Water Resources, Tatiana Borisova and Tara Wade, University of Florida Institute of Food and Agriculture (2018).

29District Remains Laser Focused on Sending Water South, supra.

30Water Quality Improvement, South Florida Water Management District (2021).

31Statement: SFWMD Responds to Increased Releases from Lake Okeechobee, South Florida Water Management District (2021).

32-33Restoration Plan: CERP, supra.

34-36Progress Continues on the Everglades Agricultural Area Reservoir Project, South Florida Water Management District (2021).

37EAA Water Reservation FAQ, South Florida Water Management District (2020).

38-39Lake Okeechobee System Operating Manual (LOSOM), a Component of the Central & Southern Florida (C&SF) System Operating Plan, U.S. Army Corp of Engineers (2021).

40Lake Okeechobee System Operating Manual, Leslye Waugh, South Florida Water Mangement District (April 8, 2021).

41Lake Okeechobee System Operating Manual (LOSOM), a Component of the Central & Southern Florida (C&SF) System Operating Plan, supra.

42Lake Okeechobee System Operating Manual (LOSOM) Preferred Alternative, U.S. Army Corp of Engineers (August 9, 2021).

43-44Lake Okeechobee System Operating Manual, supra.

45-46Lake Okeechobee System Operating Manual (LOSOM) Preliminary Preferred Alternative, U.S. Army Corp of Engineers, (July 19, 2021) (see page 8).

47LOSOM Update: Army Corps Selects Preferred Alternative, The Everglades Foundation (2021); Leaders Unite to Call on Corps to Send Water South, Sanibel-Captiva Conservation Foundation (2021).

48Tell The U.S. Army Corps LOSOM Must Be Balanced For All Stakeholders, The Conservancy of Southwest Florida (2021); Leaders Unite to Call on Corps to Send Water South, Sanibel-Captiva Conservation Foundation (2021).

49-52 Lake Okeechobee System Operating Manual (LOSOM) Preferred Alternative, supra.; Central and Southern Florida Project: Water Control Plan for Lake Okeechobee and Everglades Agricultural Area, U.S. Army Corp of Engineers (2008). Lake Okeechobee System Operating Manual (LOSOM), a Component of the Central & Southern Florida (C&SF) System Operating Plan, supra; Lake Okeechobee System Operating Manual (LOSOM) Preliminary Preferred Alternative, supra.

53Tell The U.S. Army Corps LOSOM Must Be Balanced For All Stakeholders, The Conservancy of Southwest Florida (2021); Leaders Unite to Call on Corps to Send Water South, Sanibel-Captiva Conservation Foundation (2021); Letter from Byron Donalds to Colonel Andrew Kelly (August 3, 2021); LOSOM Update: Army Corps Selects Preferred Alternative, The Everglades Foundation (2021).

54RECOVER Northern Estuaries Performance Measure: Salinity Envelope, U.S. Army Corp of Engineers (2020).

55-56Lake Okeechobee System Operating Manual (LOSOM) Preferred Alternative, supra.

57-66Lake Okeechobee System Operating Manual (LOSOM), U.S. Army Corp of Engineers (Nov. 16 2021)