South Florida Water Management District Research Articles

The largest constructed treatment wetland project in the world: The story of the Everglades stormwater treatment areas

The Everglades Stormwater Treatment Areas (STAs) are the largest complex of constructed treatment wetlands in the world with a current treatment area of over 25,000 ha which will total approximately 25,900 ha by the end of 2025. They are designed to remove phosphorus from agricultural and urban stormwater runoff, and when there is available capacity, they can also receive and treat water from Lake Okeechobee. STA-treated water is then sent south to the Everglades to support restoration and maintenance of this unique ecosystem. The recommendation to build treatment wetlands began in 1988 with the Lake Okeechobee Technical Advisory Committee, and the mandate to operate and maintain the STAs continues today through operating permits and consent orders issued to the South Florida Water Management District (SFWMD) by the Florida Department of Environmental Protection. The permits and consent orders set forth a stringent phosphorus water quality-based effluent limit (WQBEL) that must be met starting in 2026. SFWMD has conducted extensive research on treatment wetland function and phosphorus removal efficiency to support construction, management, and operation of the STAs to achieve the WQBEL. The most recent work has been conducted under the Restoration Strategies Science Plan. This 11-year research program began in 2013 and will continue through 2024 to address six key scientific questions aimed at assisting the SFWMD in meeting the WQBEL for discharges from the Everglades STAs. What follows in this Special Edition are articles discussing the results and conclusions from several of these studies.

Your Farm as a Water Storage System: Steps to Establish an Agreement with the Water Management Districts

This publication introduces water storage strategies known as Dispersed Water Management (DWM) and Water Farms (WF) and describes the process that a private landowner should follow to obtain a permit and begin a water storage agreement with the South Florida Water Management District (SFWMD) and the St. Johns River Water Management District (SJRWMD). Written by Brandon Quinn-Ivey and Sandra M. Guzmán, and published by the UF/IFAS Department of Agricultural and Biological Engineering, September 2022.

Changes in nitrogen and phosphorus within a decade in waters along a major canal and estuary in South Florida.

The West Palm Beach-C51 (WPB-C51) canal connects Lake Okeechobee with Lake Worth Lagoon (LWL) in South Florida. This canal receives discharges from Lake Okeechobee and from agricultural and urbanized areas. The objectives of this research were to determine spatial and temporal differences and trends of N and P forms along the WPB-C51 canal and LWL for 2009-2019. Data were obtained from the South Florida Water Management District. Average total P (TP) and total N (TN) concentrations at studied stations ranged from 55 to 183μg L-1 and from 0.61 to 2.62mg L-1 , respectively. The TP and TN concentrations at LWL inflow were higher than the State of Florida's regulatory criteria (49μg L-1 and 0.66mg L-1 , respectively). The TP and TN concentrations generally declined from Lake Okeechobee to LWL; however, agricultural drainage was highest for soluble reactive P (SRP) and all N forms. Temporal trends showed predominantly increasing trends for concentrations of P forms. Total P and TN load rates increased by 0.005 and 0.032 t yr-1 , respectively, at LWL inflow. Results suggest nutrient assimilation by plants and P precipitation along the WPB-C51 canal. Possible sources of SRP and N are fertilizers, nitrification, and organic matter mineralization. Increasing trends in P concentration are possibly due to legacy P and urbanization, and increases in TP and TN loads can be due to larger Lake Okeechobee discharges and higher nutrient concentrations. Results emphasize the need to implement strategies to minimize nutrient input into LWL to meet its water quality goals.

In Memoriam

He liked fish. And he liked people who liked fish. In the span of a week, Michael J. Maceina, Professor Emeritus at Auburn University, went from fishing with his family near Mobile Bay to passing peacefully at home in his own bed on June 10, 2020. During his brief battle with prostate cancer he did not stop fishing, he did not stop hunting, and he did not stop spending quality time with family and friends. Maceina earned his fisheries degrees at the University of Florida (BS, MS) and Texas A&M University (PhD). He worked as a senior environmental scientist with the South Florida Water Management District for several years before joining the Auburn University faculty in 1990, where he worked until he retired in 2015. His population dynamics graduate course was legendary. Maceina was an intense and passionate instructor. He never settled for anything less than your best and he expected you to bring your A-game every day. He certainly always brought his. His students benefitted from his energy and drive to solve fishery problems with rigorous data analysis and a critical eye for investigating data trends and patterns. When he wasn’t fishing or hunting with family and friends, Maceina was a dynamic researcher and prolific author, penning 127 peer-reviewed manuscripts and book chapters. His nickname “Iron Mike” may have come from his dealings with reviewers and editors. He also answered to “Dr. N,” a nod towards his advocacy for large sample sizes and resultant statistical power. Mike and his collaborators made seminal contributions in their studies of relationships between trophic states and fisheries, harvest regulations, age and growth of fish, fish habitat requirements, vegetation management, and environmental drivers of fish recruitment. Mike developed the methodology to use residuals from catch-curves to index year class strength and that influential 1997 paper has been widely adopted by freshwater and marine biologists. Yield models have been the bread-and-butter of marine stock assessments for many years, but were less commonly employed in studies of freshwater fisheries before 2000. Maceina and his student coauthor helped change that when they developed Windows-based FAST/FAMS software. Together, they hosted dozens of workshops to teach several generations of freshwater biologists how to use sophisticated yield models to forecast the effects of regulation changes on fish populations. Given his penchant for studying fisheries management problems, it is not surprising that he coauthored the Best Paper of 2016 in the North American Journal of Fisheries Management (10 years earlier, he coauthored a paper that was a finalist for that prestigious award). Mike was inducted into the Fisheries Management Section’s Hall of Excellence in 2017. He was an AFS Life Member and an active participant at state, regional, and AFS Annual Meetings and symposia for 35 years. He was also active in the North American Lake Management Society and the Aquatic Plant Management Society. Maceina always felt a connection to southeastern U.S. ecosystems and the management of aquatic vegetation and nutrients in lakes and reservoirs. Your endeavors were nearly always successful if Maceina was your co-principal investigator or coauthor. If he was your friend, well, you could find no better. If he was your advisor you counted yourself lucky—perhaps not at the exact moment when he was delivering a well-timed “attitude adjustment,” but later you certainly did. Maceina mentored 28 graduate students who fanned out across the USA and the world to continue his work. That achievement is perhaps his greatest legacy as a fisheries scientist. His son Vaughn Trout Maceina, his daughter-in-law Claire, and their two children survive him. His wife Nellie passed away before he did. A memorial endowment in the School of Fisheries, Aquaculture, and Aquatic Sciences at Auburn University has been established. Contributions can be made out and sent to the AU Foundation in Mike’s name at College of Agriculture Development Office, 100 Comer Hall, Auburn, AL 36849-5401.

Estimating Late 19th Century Hydrology in the Greater Everglades Ecosystem: An Integration of Paleoecologic Data and Models

Restoration of the Greater Everglades Ecosystem requires an understanding of the hydrology of the natural system prior to significant alterations due to water management and land use. Large scale models such as the Natural Systems Model (NSM 4.6.2) have been used by the South Florida Water Management District and other agencies responsible for restoration to estimate past hydrologic conditions; however, these models typically portray a drier natural system for the beginning of the 20th century than what is indicated by paleoecologic analyses and historical data. The purpose of this study is to estimate pre-20th century water levels, hydroperiods and flow in the freshwater wetlands of the Everglades by using pollen assemblage data in three sediment cores to adjust the Natural Systems Model. This study is designed to further test estimates of flow through the Everglades derived from analysis of sediment cores collected in Florida Bay. The results demonstrate that the NSM 4.6.2 underestimates water levels and hydroperiods in the Everglades compared to the paleo-adjusted NSM 4.6.2 model outputs. Flow models that use the paleo-adjusted water levels as input indicate flow through Shark River Slough in the late 19th century was approximately two times observed levels, and flow through Taylor Slough was approximately three times observed levels. The flow estimates derived from this study agree with the estimates derived from earlier studies using estuarine cores.

WITHDRAWN: Restoring the Florida Everglades Comments on the current reservoir plan for solving harmful algal blooms and restoring the Florida Everglades

Preface This is an updated version of a review written by the author in April 2018 at the request of The Friends of the Everglades, an NGO based in Miami, Florida, on a plan developed primarily by the South Florida Water Management District (SFWMD) to mitigate coastal pollution that has resulted from discharges from Lake Okeechobee to the Gulf of Mexico and Atlantic coastline and eventually to “send the water south” to the Florida Everglades instead. This EAA Reservoir project was included by the U.S. Army Corps of Engineers in a 2018 U.S. Congressional bill that was approved. In May 2019, U.S. President Donald Trump pledged to spend $200 million to begin construction of this restoration, three times the amount requested by the state of Florida. While supported with enthusiasm by the Florida state legislature, the SFWMD, and some NGOs such as The Everglades Foundation, a change in leadership in the state of Florida after November 2018 elections and especially in the leadership of the South Florida Water Management District (SFWMD) has led to a renewed public optimism for major improvements in water quality management in south Florida. It is therefore timely for this review of the advantages and shortcomings of this “EAA (Everglades Agricultural Area) Reservoir Plan” to be widely disseminated in an international forum such as Ecological Engineering to encourage discussions among scientists and engineers.

Best Management Practices in the Everglades Agricultural Area: Controlling Particulate Phosphorus and Canal Sediments

The South Florida Water Management District has developed a BMP table that lists the BMP practices that have been designed to reduce particulate P and sediment loads in drainage waters from Everglades Agricultural Area (EAA) farms. The purpose of this document is to explain and discuss these particulate P and sediment control practices. These practices serve as important tools in efforts to improve water quality in the basin. This EDIS article is one in a series that attempts to explain in easily understandable terms the implementation methods and rationale behind the main P load reducing BMPs employed on EAA farms. This document is SL228, a fact sheet of the Soil and Water Science Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date August 2005.
 SL228/SS448: Best Management Practices in the Everglades Agricultural Area: Controlling Particulate Phosphorus and Canal Sediments (ufl.edu)

Best Management Practices in the Everglades Agricultural Area: Fertilizer Spill Prevention

Phosphorus fertilizer spill prevention is a Best Management Practice (BMP) approved by the South Florida Water Management District (SFWMD), one designed to reduce drainage P loads in the Everglades Agricultural Area (EAA). Spill prevention of P fertilizers is a BMP that is widely implemented by growers in the EAA. This BMP is easily implemented and can have an immediate impact on reducing off-farm P loads. This EDIS document is part of a series of publications that provide current implementation guidelines for commonly employed farm-level BMPs designed to reduce P loads from farms located within the EAA basin. This document is SL231, one of a series of the Department of Soil and Water Sciences, UF/IFAS Extension. Original publication date September 2005.
 SL231/SS450: Best Management Practices in the Everglades Agricultural Area: Fertilizer Spill Prevention (ufl.edu)

Restoring the Florida Everglades: Comments on the current reservoir plan for solving harmful algal blooms and restoring the Florida Everglades

This is an updated version of a review written by the author in April 2018 at the request of The Friends of the Everglades, an NGO based in Miami, Florida, on a plan developed primarily by the South Florida Water Management District (SFWMD) to mitigate coastal pollution that has resulted from discharges from Lake Okeechobee to the Gulf of Mexico and Atlantic coastline and eventually to “send the water south” to the Florida Everglades instead. This EAA Reservoir project was included by the U.S. Army Corps of Engineers in a 2018 U.S. Congressional bill that was approved. In May 2019, U.S. President Donald Trump pledged to spend $200 million to begin construction of this restoration, three times the amount requested by the state of Florida. While supported with enthusiasm by the Florida state legislature, the SFWMD, and some NGOs such as The Everglades Foundation, a change in leadership in the state of Florida after November 2018 elections and especially in the leadership of the South Florida Water Management District (SFWMD) has led to a renewed public optimism for major improvements in water quality management in south Florida. It is therefore timely for this review of the advantages and shortcomings of this “EAA (Everglades Agricultural Area) Reservoir Plan” to be widely disseminated in an international forum such as Ecological Engineering to encourage discussions among scientists and engineers.

Florida’s recycled water footprint: a geospatial analysis of distribution (2009 and 2015)

Water shortages resulting from increased demand or reduced supply may be addressed, in part, by redirecting recycled water for irrigation, industrial reuse, groundwater recharge, and as effluent discharge returned to streams. Recycled water is an essential component of integrated water management and broader adoption of recycled water will increase water conservation in water-stressed coastal communities. This study examined spatial patterns of recycled water use in Florida in 2009 and 2015 to detect gaps in distribution, quantify temporal change, and identify potential areas for expansion. Databases of recycled water products and distribution centers for Florida in 2009 and 2015 were developed by combining the 2008 and 2012 Clean Water Needs Survey databases with Florida’s 2009 and 2015 Reuse Inventory databases, respectively. Florida increased recycled water production from 674.85 mgd in 2009 to 738.15 mgd in 2015, an increase of 63.30 mgd. The increase was primarily allocated to use in public access areas, groundwater recharge, and industrial reuse, all within the South Florida Water Management District (WMD). In particular, Miami was identified in 2009 as an area of opportunity for recycled water development, and by 2015 it had increased production and reduced the production gap. Overall, South Florida WMD had the largest increase in production of 44.38 mgd (69%), while Southwest Florida WMD decreased production of recycled water by 1.68 mgd, or 3%. Overall increase in use of recycled water may be related to higher demand due to increased population coupled with public programs and policy changes that promote recycled water use at both the municipal and individual level.

Effects of short-duration hydraulic pulses on the treatment performance of a periphyton-based treatment wetland

The effect of high flows on total phosphorus (TP) removal in a 40-ha periphyton-based stormwater treatment area wetland (PSTA Cell) located in Stormwater Treatment Area (STA)-3/4 was evaluated by subjecting the PSTA Cell to three short-duration (3-day) hydraulic (high-inflow) pulses. The intent was to mimic hydraulic conditions that would be experienced during large storm events should the PSTA concept be implemented throughout the complex of treatment wetlands (STAs) operated by the South Florida Water Management District for Everglades restoration. The average inflow rate to the PSTA Cell during the pulses (1.3–2.0m3s−1) was approximately three to four times higher than under normal operation. The hydraulic loading rates (HLRs) during the pulses (28–43cmd−1) matched the peak 3-day HLRs observed in STA-3/4 during high inflows associated with storm runoff. Correspondingly, the phosphorus loading rates (PLRs) and hydraulic retention times (HRTs) during the pulses (2.3–6.3mgm−2d−1 and 1.4–1.8 days, respectively) were substantially higher and lower, respectively, compared to PLRs and HRTs in the PSTA Cell under normal operation. No reduction in TP removal performance was observed in the PSTA Cell during the pulses, and there was no indication that post-pulse outflow TP concentrations increased compared to pre-pulse levels in response to the pulse events. The short-term increase in hydraulic and TP loads during this study did not compromise the treatment efficacy of the PSTA Cell. If implementable in a cost-effective manner in the STAs, the PSTA concept could be part of a treatment strategy that achieves TP effluent limits mandated for these wetlands.

Development of a new model tool for evaluating groundwater resources within the Floridan Aquifer System in Southern Florida, USA

The US Army Corps of Engineers (USACE) and the South Florida Water Management District (SFWMD) are partners in an ambitious plan to restore water flows throughout the Everglades ecosystem. An important component of the restoration plan involves storing excess stormwater deep underground in the Floridan Aquifer System using aquifer, storage and recovery (ASR) wells. In order to determine the optimal ASR system and to assess environmental impacts, USACE spent over 11 years and significant resources to develop a three-dimensional groundwater model of the Floridan Aquifer System covering a large portion of the Florida peninsula. This SEAWAT model is capable of evaluating changes in aquifer pressures and density-dependent flows in the entire study area. The model has been used to evaluate the Everglades ASR system already but could also be used by water managers for other important water resources studies in Florida including water supply estimates and adaptation to climate change. As part of an effort to make the model more readily available for other important studies, this study documents and summarizes the overall development of the SEAWAT model including a discussion regarding the intensive calibration and validation efforts undertaken during model development. The paper then demonstrates the use of the model using Everglades ASR project alternatives. Lastly, the paper outlines potential future uses of the model along with its overall limitations. Supplementary online resources are also included that provide researchers with further detail regarding the model development effort beyond the scope of this summary article as well as model development databases.

Experimental Demonstration of a New Extension Plate Scour Countermeasure Downstream of Stilling Basins

AbstractLaboratory experiments were conducted in order to investigate the effectiveness of a new scour countermeasure consisting of a horizontal extension plate (EP) downstream of a gated spillway-stilling basin structure. These experiments were performed on a 1:30 scale model of one of the South Florida Water Management District (SFWMD) gated spillway structures, the S65E gated spillway, because it has experienced worrisome downstream scour. Currently, riprap is the only scour countermeasure documented for these structures. EPs of various lengths were installed downstream of the stilling basin, and the equilibrium scour was measured. It was found that a plate length of approximately 1.88 times the exiting flow depth was the shortest length that resulted in significant scour reduction and downstream scour translation. Measured flow patterns reveal that the EP altered the flow patterns by transferring the plunging flow downstream and eliminating the near-bed reattachment and surface recirculation, possibly...

Effect of Submergence and Apron Length on Spillway Scour: Case Study

Large-scale water resources systems are often managed by an integrated set of hydraulic structures that are vulnerable to wider ranges of discharge and tailwater elevation than envisioned in their original design due to climate change and additional project objectives such as fostering healthy ecosystems. The present physical model study explored the performance of a spillway structure on the Kissimmee River, operated by the South Florida Water Management District, under extreme conditions of drought and flooding with accompanying low and high tailwater levels for both gate-controlled and uncontrolled spillway flow conditions. Maximum scour depths and their locations for two different riprap apron lengths downstream of the spillway stilling basin were measured along with the complex flow fields prior to scour. Effects of tailwater submergence, type of spillway flow and riprap apron length on scour results are interpreted in terms of the measured turbulent kinetic energy and velocity distributions near the bed.

Operational Actual Wetland Evapotranspiration Estimation for South Florida Using MODIS Imagery

Evapotranspiration is a reliable indicator of wetland health. Wetlands are an important and valuable ecosystem on the South Florida landscape. Accurate wetland Actual Evapotranspiration (AET) data can be used to evaluate the performance of South Florida’s Everglades restoration programs. However, reliable AET measurements rely on scattered point measurements restricting applications over a larger area. The objective of this study was to validate the ability of the Simplified Surface Energy Balance (SSEB) approach and the Simple Method (also called the Abtew Method) to provide large area AET estimates for wetland recovery efforts. The study used Moderate Resolution Imaging Spectroradiometer (MODIS) sensor spectral data and South Florida Water Management District (SFWMD) solar radiation data to derive weekly AET values for South Florida. The SSEB-Simple Method approach provided acceptable results with good agreement with observed values during the critical dry season period, when cloud cover was low (rave (n = 59) = 0.700, pave < 0.0005), but requires further refinement to be viable for yearly estimates because of poor performance during wet season months, mainly because of cloud contamination. The approach can be useful for short-term wetland recovery assessment projects that occur during the dry season and/or long term projects that compare site AET rates from dry season to dry season.

Implementing Legally Mandated Science and Peer Review in Support of the Everglades Restoration Program

The Everglades Forever Act mandates that the Florida Department of Environmental Protection and the South Florida Water Management District conduct any research necessary to numerically interpret Florida’s existing phosphorus criterion narrative standard, which requires phosphorus levels cause no imbalance in flora and fauna. The Act commands such research to: meet ambitious deadlines, utilize spatial-scaled science, incorporate substantive peer review, be open for public comment, and be published in scientific literature. These commands riddle phosphorus research with multiple obstacles.This article reviews phosphorus criterion research in the Everglades as an example of scientific excellence resulting from open publication in light of litigation, urgency, and ultimate need to support decision making on definitive phosphorus standards. Specifically, the article begins by reviewing the everglades system and its environmental issues, including those resulting from increased phosphorus levels. The article continues on to summarize the Everglades phosphorus research processes, challenges, and resulting benefits.Ultimately, the article supports the use of phosphorus research in the Everglades as a model example of the positive effects that can result when research is conducted in an open research process.

Bringing the Benefits of Tree Islands Back to the Everglades

Bringing the Benefits of Tree Islands Back to the Everglades

Geostatistics-based groundwater-level monitoring network design and its application to the Upper Floridan aquifer, USA.

A geostatistical method was applied to optimize an existing groundwater-level monitoring network in the Upper Floridan aquifer for the South Florida Water Management District in the southeastern United States. Analyses were performed to determine suitable numbers and locations of monitoring wells that will provide equivalent or better quality groundwater-level data compared to an existing monitoring network. Ambient, unadjusted groundwater heads were expressed as salinity-adjusted heads based on the density of freshwater, well screen elevations, and temperature-dependent saline groundwater density. The optimization of the numbers and locations of monitoring wells is based on a pre-defined groundwater-level prediction error. The newly developed network combines an existing network with the addition of new wells that will result in a spatial distribution of groundwater monitoring wells that better defines the regional potentiometric surface of the Upper Floridan aquifer in the study area. The network yields groundwater-level predictions that differ significantly from those produced using the existing network. The newly designed network will reduce the mean prediction standard error by 43% compared to the existing network. The adoption of a hexagonal grid network for the South Florida Water Management District is recommended to achieve both a uniform level of information about groundwater levels and the minimum required accuracy. It is customary to install more monitoring wells for observing groundwater levels and groundwater quality as groundwater development progresses. However, budget constraints often force water managers to implement cost-effective monitoring networks. In this regard, this study provides guidelines to water managers concerned with groundwater planning and monitoring.

The application of oyster and seagrass models to evaluate alternative inflow scenarios related to Everglades restoration

The South Florida landscape is highly engineered featuring ∼3380km of canals, ∼1225 water control structures, >70 pumping stations, managed wetlands, densely populated coastal watersheds, and impacted estuaries. Landscape scale agricultural and urban modifications require flood control which sometimes results in the release of excess freshwater that potentially damages estuarine ecology. The Central Everglades Planning Project (CEPP) is a partnership between the U.S. Army Corps of Engineers and the South Florida Water Management District focused on restoring natural patterns of freshwater flow to the Everglades and associated estuaries. One of the primary project goals is to reduce deleterious inflows eastward to the St. Lucie Estuary (SLE) and westward to the Caloosahatchee River Estuary (CRE) by diverting freshwater south from Lake Okeechobee. Performance evaluation of the CEPP relies upon integrated modeling which links the watershed engineering projects to estuarine salinities and biotic responses. The objective of this study was to utilize seagrass and oyster models to evaluate the effectiveness of alternative inflow scenarios. There are three different scenarios: the existing condition base (ECB), the future without proposed CEPP projects (FWO) but with other landscape features that could alter freshwater inflows, and alternative 4R (ALT4R) that incorporates a suite of restoration projects including those associated with the CEPP. Each of these inflow scenarios was used to generate daily salinity time series from 1965 to 2005 at multiple locations in the SLE and CRE which were used to run site-specific seagrass and oyster models. The hydrodynamic and ecological effects of freshwater inflow were greater in the SLE compared to the much larger CRE. Predicted densities of oysters (individualsm−2) and seagrass (shootsm−2) were greater in the wet season (May–Oct) vs. the dry season (Nov–Apr) in both estuaries. Oyster and seagrass densities increased under the ALT4R inflow scenario that mitigated high inflows to the estuaries in the wet season. This result improved environmental conditions while increasing freshwater availability for other parts of the Greater Everglades and the southern estuaries such as Florida Bay and Biscayne Bay.

A simple method for routine monitoring of glyphosate and its main metabolite in surface waters using lyophilization and LC-FLD + MS/MS. Case study: canals with influence on Biscayne National Park

A novel method was developed for the analysis of the herbicide glyphosate and its main metabolite aminomethylphosphonic acid (AMPA) based on lyophilization. Sample preparation steps are limited to fortification with aspartic acid as internal standard and water removal by lyophilization (3–4 days for 72 samples), followed by suspension of dry residues in borate buffer (pH=9.0) and addition of ethylenediaminetetraacetic acid (EDTA) and 9-fluorenylmethylchloroformate (FMOC-Cl) for pre-column derivatization. The obtained derivatization mixture was injected on a highly endcapped C18 column where a basic pH gradient separation of the anionic analytes from neutral derivatization byproducts was achieved, with simultaneous quantitation by fluorescence and compound confirmation by tandem mass spectrometry. Method detection limits (for 20mL samples) were 0.058μg/L and 0.108μg/L for glyphosate and AMPA, respectively. The method had a high dynamic range (0.1–50.0μg/L) which allowed quantitation at both background and high levels of the herbicide. As a case study, the methodology was successfully applied to detect the occurrence of these compounds in water canals managed by the South Florida Water Management District. These canals will be used as freshwater source to hydrate estuarine wetlands of Biscayne National Park under the Comprehensive Everglades Restoration Project, in order to decrease ecosystem stress from hypersaline conditions caused by anthropogenic reduction of historical freshwater flow towards the Biscayne Bay. Method development, validation, advantages, limitations and measured environmental concentrations are discussed. This methodology has minimal requirements in terms of materials, instruments and analyst training, which could represent a desirable tool for laboratories interested in the monitoring of glyphosate in surface waters.