About

The U.S. Army Corps of Engineers (USACE) finalized the Lake Okeechobee System Operating Manual (LOSOM) in August 2024, replacing the previous Lake Okeechobee Regulation Schedule (LORS). LOSOM incorporates key infrastructure improvements, including the rehabilitation of the Herbert Hoover Dike, the Kissimmee River Restoration Project, the C-43 West Basin Storage Reservoir, and the C-44 Reservoir and Stormwater Treatment Area, which are part of the Comprehensive Everglades Restoration Plan (CERP). These updates enable better management of water levels to improve flood protection, water quality, and ecosystem health while reducing harmful discharges to surrounding estuaries. 

The Process

The Corps hosted a series of National Environmental Policy Act (NEPA) public scoping meetings in addition to public workshops and Project Delivery Team (PDT) meetings throughout South Florida since January of 2019. The PDT meetings allowed representatives from various government agencies and the public to provide input on the LOSOM plan.

To ensure a thorough and transparent process, six sub-teams were formed, focusing on key areas: Ecology, Engineering, Economics, Water Supply, Water Quality/HAB (Harmful Algal Blooms), and Modeling and Plan Formulation.  

After several years of meetings, collaboration, and in-depth evaluation, the new LOSOM was finalized in August 2024 by the U.S. Army Corps of Engineers and will guide future water management operations for Lake Okeechobee​.

Martin County's Efforts

Martin County was actively engaged in the LOSOM review and evaluation process and assembled a team of subject matter experts to conduct research, evaluate options, provide input and develop strategies to advocate on behalf of our residents, visitors and environment. This team included a variety of scientists, climatologists, hydrogeologists, engineers and environmental legal specialists.

Martin County will continue to make elective investments in water quality. Water quality isn’t just about what happens with Lake Okeechobee and LOSOM, which is why Martin County is extremely active in creating proprietary research and developing water quality improvement projects to help protect the health and well-being of our residents, businesses, environment and way of life. Learn more about our water quality efforts.

Martin County Letter to USACE Re: Response to the July 2022 Draft Environmental Impact Statement (DEIS) regarding LOSOM –September 12, 2022, the Martin County Board of County Commissioners submitted a letter to the U.S. Army Corps of Engineers (USACE) regarding the July 2022 Draft Environmental Impact Statement (DEIS). 

Martin County Letter to USACE Re: LOSOM Re-write – March 31, 2022, the Martin County Board of County Commissioners submitted a letter to the U.S. Army Corps of Engineers (USACE) regarding a recent USACE workshop where they revealed the latest draft of the LOSOM Water Control Plan. 

Martin County Operational Guidance Letter – October 15, 2021, the U.S. Army Corps of Engineers is currently developing operational criteria for Lake Okeechobee as part of the new proposed schedule. These concepts utilized forecasting and predictive tools to dictate when discharges could occur from the Lake. In this letter, Martin County staff explain why we oppose these operational criteria proposed by USACE.

Martin County LOSOM Iteration 3 Letter (RECOVER Stressful Flow Exceedance Counts Comparison) – On August 18, 2021, County staff submitted a letter to Colonel Andrew Kelly with USACE regarding the LOSOM Preferred Alternative CC that was selected by USACE on August 9th. Martin County is aware that Caloosahatchee River (CRE) stakeholders have specifically requested that Alternative CC be “optimized” to include additional harmful Lake Okeechobee discharges to the St. Lucie River (SLE) within Zone D. In this letter, the County demonstrates through modeled data that, if Alternative CC is “optimized” in this manner, LOSOM will undoubtedly result in greater harm to the SLE than the CRE, akin to current conditions under LORS08. Through this letter, Martin County reiterates our objection to the concept of sending more water to the SLE within the Alternative CC optimization process.

Martin County LOSOM Conceptual Plan Evaluation Comment Letter No. 2 – On December 17, 2020, the Martin County Board of County Commissioners submitted comments to the U.S. Army Corps of Engineers (USACE) regarding the development of a new Lake Okeechobee schedule. The USACE is currently in the process of selecting an initial array of new Lake Okeechobee Schedules as part of the Lake Okeechobee System Operating Manual (LOSOM) process. Their approach separated stakeholders into several sub-groups, including the St. Lucie Estuary, Caloosahatchee Estuary, Water Supply, Navigation, Recreation, Lake Okeechobee Ecology, and South Florida Ecology. The USACE provided 27,000 Lake Okeechobee schedule options, and requested that stakeholders provide schedules per each sub group. Martin County provided schedules that fell under USACE’s 4C-1 category, which includes zero discharges to the St. Lucie River through the S-80 structure, or the St. Lucie Lock. 

Martin County LOSOM Conceptual Plan Evaluation Comment Letter No. 1 – On December 7, 2020, the Martin County Board of County Commissioners submitted comments to The U.S. Army Corps of Engineers (USACE) regarding the development of a new Lake Okeechobee schedule. The USACE is currently in the process of selecting an initial array of new Lake Okeechobee Schedules as part of the Lake Okeechobee System Operating Manual (LOSOM) process. Their approach separated stakeholders into several sub-groups, including the St. Lucie Estuary, Caloosahatchee Estuary, Water Supply, Navigation, Recreation, Lake Okeechobee Ecology, and South Florida Ecology. The USACE provided 27,000 Lake Okeechobee schedule options, and requested that stakeholders provide schedules per each sub group. Martin County provided schedules that fell under USACE’s 4C-1 category, which includes zero discharges to the St. Lucie River through the S-80 structure, or the St. Lucie Lock. 

Martin County LORS HAB Environmental Assessment Deviation Comment Letter – On July 30, 2020, the Martin County Board of County Commissioners submitted comments to the U.S. Army Corps of Engineers (USACE) regarding the LORS HAB Environmental Assessment Deviation. The Corps is proposing a planned deviation from LORS 2008 in anticipation of and following freshwater Harmful Algal Blooms (HABs), to help reduce the risk of potential concerns associated with algal blooms in Lake Okeechobee, the St. Lucie, and Caloosahatchee estuaries while maintaining other project purposes. This Draft Revised Supplemental EA is being prepared to address comments received in response to the 2019 LORS Planned Deviation Draft EA provided to the public on August 6, 2019 and to supplement the LORS 2008 Final Supplemental Environmental Impact Statement. The proposed action occurs in Glades, Hendry, Martin, Okeechobee, and Palm Beach counties, Florida.

Restoration Coordination and Verification Program (RECOVER) Salinity Envelope Performance Measure – On May 28, 2020, the Martin County Board of County Commissioners submitted comments to the U.S. Army Corps of Engineers (USACE) regarding recommendations to improve the Salinity Envelope Performance Measure to the RECOVER team. This performance measure accounts for salinity ranges that occur in the Northern Estuaries based on freshwater inflows, and how those inflows could stress or damage oyster and Seagrass populations. This performance measure will be used to evaluate alternative lake schedules proposed by the USACE. 

Savings Clause Letter – On May 19, 2020, the Martin County Board of County Commissioners submitted a letter to Congressional members regarding recent efforts to extend the "Savings Clause" in Water Resources Development Act ("WRDA") 2000 to the ongoing development of the Lake Okeechobee System Operating Manual (LOSOM).

St. Lucie Estuary Basin Management Action Plan (SLE BMAP), Request for a 60 Day Extension of Time to File a Petition for an Administrative Hearing – On February 20, 2020, the Martin County Board of County Commissioners submitted a letter to the Florida Department of Environmental Protection requesting a 60 day extension from the standard 21 days within which an administrative petition is due from the issuance of the BMAP Final Order so that Martin County can further review and evaluate benefits and implications of the BMAP on the ultimate health and restoration of the Estuary. 

Sensitivity Runs and Performance Metrics Follow Up Letter – On January 31, 2020, the Martin County Board of County Commissioners submitted a letter to the U.S. Army Corps of Engineers, Jacksonville District, providing further response to a request for input from the Project Delivery Team (PDT) on sensitivity runs and performance metrics that will be used in the LOSOM development.

BMAP Letter – On January 14, 2020, the Martin County Board of County Commissioners provided comments on the Florida Department of Environmental Protection's (DEP) St. Lucie River and Estuary Basin Management Action Plan (BMAP) Draft Update. This letter expresses the county's concerns and recommendations regarding updates to the BMAP modeling approach, proposed management practices for managing nutrient reductions, the revised monitoring plan, and numerical errors found on the county's project list.

Sensitivity Runs and Performance Metrics Letter – On December 11, 2019, the Martin County Board of County Commissioners submitted a letter to the U.S. Army Corps of Engineers, Jacksonville District, regarding input from the Project Delivery Team (PDT) on sensitivity runs and performance metrics to be used for the LOSOM analysis.

CWA Triennial Review Letter No. 2 – On November 22, 2019, the Martin County Board of County Commissioners submitted a letter as supplemental public comment on the Florida Department of Environmental Protection's (DEP) Triennial Review of the Surface Water Quality Standards in Chapter 62-302, Florida Administrative Code. This supplemental letter has two sections relevant to the Triennial Review. Section I addresses turbidity standards. Section II addresses and reiterates Martin County's position that DEP should adopt qualitative and quantitative standards for Microcystin and Cylindrospermopsin.

Martin County Response to LORS08 – On September 5, 2019, the Martin County Board of County Commissioners provided comments and support to the Department of The Army, Jacksonville District Corps of Engineers concerning the proposed LORS08 Planned Deviation from the 2008 Lake Okeechobee Regulation Schedule (LORS08).

Biosolids Letter – On August 6, 2019, the Martin County Board of County Commissioners provided comments to the Florida Department of Environmental Protection on proposed revisions to Chapter 62-640, F.A.C., regarding review of management practices and potential nutrient impacts related to the land application of biosolids.

CWA Triennial Review Letter No. 1 – On May 30, 2019, the Martin County Board of County Commissioners submitted a letter on the Florida Department of Environmental Protection's (DEP) Triennial Review of the Surface Water Quality Standards in Chapter 62-302, Florida Administrative Code. This letter presents Martin County's position that DEP should adopt qualitative and quantitative standards for Microcystin and Cylindrospermopsin.

A series of National Environmental Policy Act (NEPA) public scoping meetings were held throughout South Florida during February and March 2019. Public scoping comments were accepted until April 22, 2019.

Reports

Water Institute LOSOM Synthesis Report

The University of Florida Water Institute was hired to conduct an independent scientific review to help inform the development of the next Lake Okeechobee Regulation Schedule. To do so, the Water Institute convened an interdisciplinary academic review team that:

  1. Acquired and synthesized existing scientific information related to the impacts of the Lake Okeechobee regulation schedule on the ecology of Lake Okeechobee and the estuaries that receive lake discharges;
  2. Identified knowledge gaps and additional data needed to assess the ecological impacts and tradeoffs of proposed changes to LORS; and
  3. Developed recommendations and priorities for new efforts needed to fill gaps in existing knowledge