Beach Water Research Articles

Microbial source tracking to address of bacterial contamination in recreational waters

Abstract Background Beach closures in the USA are determined by fecal indicator bacteria thresholds, which are insufficient to identify causes of contamination. We use microbial source tracking (MST) to identify the species source of bacteria entering chronically impaired waters. We find canine bacteria is the primary source of high E.coli levels and demonstrate the power of MST for direction of remediation efforts. Methods This environmental sampling study was performed in Short Beach, Branford, Connecticut, USA. Water samples were collected from outfalls under wet and dry precipitation conditions by 10 Citizen Scientist volunteers. The highest E.coli samples were analyzed for avian, human, and canine markers using MST. Results E.coli from 103 samples was tested from April-October 2023. Pearson’s r between average site E.coli and same day precipitation was 0.71 (p-value = 0.006). Among the high E.coli samples, 19 (76%) were low/non detectable, 5 (20%) were moderate, and 1 (4%) were high for human tracers; 10 (50%) were low/non detectable and 10 (50%) were moderate for avian tracers, and 3 (15%) were low/non detectable, 11 (55%) were moderate, and 6 (30%) were high for canine tracers. Conclusions Precipitation is a driver of elevated bacteria levels. Canine bacteria is likely the primary source of elevated bacterial levels in beach waters, while avian contributors are of moderate concern and human contributors are of low concern. As a result, an education campaign and watertight waste receptacles, rather than costly sewer line replacements, are being deployed to improve beach quality. Key messages • Use of microbial source tracking found canine bacteria is the likely driver of elevated E.coli levels in local beaches, initiating a community education campaign rather than costly sewer replacements. • Microbial source tracking technology offers a powerful public health tool for identifying causes of bacterial contamination in chronically impaired recreational waters.

Beach Quality Evaluation as a Strategy for Sustainable Coastal Tourism Management

This study evaluates the quality and visitor satisfaction across Anyer Beach, Tanjung Lesung Beach, Carita Beach, and Sawarna Beach in Banten, Indonesia, using the Bath Area Registration and Evaluation (BARE) survey and Importance-Performance (I-P) Matrix analysis. Each beach's attributes, including security, water quality, facilities, litter management, and scenery, are assessed to identify strengths and areas for improvement. The findings reveal varying levels of performance and visitor satisfaction, highlighting notable gaps in safety, medical facilities, showers, waste facilities, and changing rooms. Recommendations include enhancing safety measures, upgrading medical and shower facilities, improving waste management practices, and preserving scenic beauty to enhance visitor experiences and support sustainable tourism practices.

Bycatch discard patterns in a tropical beach seine fishery across different monsoonal periods

ABSTRACT The beach seine fishery at Oruwella, Tangalle, Sri Lanka (6°1'51“N; 80°ˊ47'57”E) was studied for its discarded bycatch over 34 months. Fishes of the benthic family-Cynoglossidae were most frequent (40.5 %) for the whole study period while jellyfish (Aurelia sp) showed the highest catch frequency (77.2 %) during the southwest monsoon. The species composition of the bycatch (per haul) was higher during the northeast monsoon than the other two periods. Thus, monsoonal and incidental jellyfish (Aurelia sp) blooms had significant impacts on the abundance and species composition of the bycatch. The study reported 26 bycatch species where 65 % and 73% of the bycatch organism types were benthic and non-commercial species respectively. As 72.6 % of hauls had less than 20 bycatch individuals, the total bycatch abundance (per haul) was comparatively low. The study also revealed the lowest number of discarding bycatch species among other studies. Cod-end made with relatively large (>0.5cm) mesh and traditional knowledge of fishers to forecast specific commercial fish schools contributed to lowering the abundance and the bycatch species in this fishery. As alive bycatch is thrown back into the beach water, the chances of survival are likely to be increased for some bycatch individuals.

Estimating Concentration of Suspended Solids Load in Estuary System Utilizing Sentinel 2A: A Case Study of Cipatujah Beach, Indonesia

Abstract Total Suspended Soil (TSS) and Total Dissolved Solid (TDS) refer to materials in the form of sediment and organic substances suspended and dissolved in water which are used as water quality parameters to understand sediment transport, the health of aquatic ecosystems, and technical problems. Concentrations in significant amounts in water areas can be caused by the dynamics of the earth’s surface and human activities, the resulting negative impacts will reduce the quality of the ecological system and indicate the presence of pollutants. This research was conducted to determine the concentration of Total Suspended Soil (TSS) and Total Dissolved Solid (TDS) in estuary waters at Cipatujah Beach, West Java, Indonesia using remote sensing satellite imagery, namely Sentinel-2A. The research carried out focused on testing samples for Total Dissolved Solid (TDS) content, which is one indicator of the level of water pollution that is often analyzed. From the results of sample tests carried out using a TDS meter, it shows that the TDS content in Cipatujah Beach is above 400 ppm so it is not suitable for use as drinking water, and further laboratory tests need to be carried out to determine the TSS content in Cipatujah Beach water.

Canadian beach cohort study: protocol of a prospective study to assess the burden of recreational water illness

BackgroundRecreational water activities at beaches are popular among Canadians. However, these activities can increase the risk of recreational water illnesses (RWI) among beachgoers. Few studies have been conducted in Canada to determine the risk of these illnesses. This protocol describes the methodology for a study to determine the risk and burden of RWI due to exposure to fecal pollution at beaches in Canada.MethodsThis study will use a mixed-methods approach, consisting of a prospective cohort study of beachgoers with embedded qualitative research. The cohort study involves recruiting and enrolling participants at public beaches across Canada, ascertaining their water and sand contact exposure status, then following-up after seven days to determine the incidence of acute RWI outcomes. We will test beach water samples each recruitment day for culture-based E. coli, enterococci using rapid molecular methods, and microbial source tracking biomarkers. The study started in 2023 and will continue to 2025 at beaches in British Columbia, Manitoba, Ontario, and Nova Scotia. The target enrollment is 5000 beachgoers. Multilevel logistic regression models will be fitted to examine the relationships between water and sand contact and RWI among beachgoers. We will also examine differences in risks by beachgoer age, gender, and beach location and the influence of fecal indicator bacteria and other water quality parameters on these relationships. Sensitivity analyses will be conducted to examine the impact of various alternative exposure and outcome definitions on these associations. The qualitative research phase will include focus groups with beachgoers and key informant interviews to provide additional contextual insights into the study findings. The study will use an integrated knowledge translation approach.DiscussionInitial implementation of the study at two Toronto, Ontario, beaches in 2023 confirmed that recruitment is feasible and that a high completion rate (80%) can be achieved for the follow-up survey. While recall bias could be a concern for the self-reported RWI outcomes, we will examine the impact of this bias in a negative control analysis. Study findings will inform future recreational water quality guidelines, policies, and risk communication strategies in Canada.

Assessing the impact of climate change on Vector-Borne Diseases: Strategies for Prevention and Control

Climate change is occurring on a worldwide scale. Human wellbeing, beach front networks, food creation, water supplies, and air quality are as of now being influenced by this change. Over 17% of all infectious sicknesses are vector-borne. There is growing information regarding how vector-borne diseases are impacted by climate change. In request to address the ramifications of climate change on VBDs in India through this paper, we assembled optional information in September 2022 from books, studies, diaries, and distributed articles on this significant subject. This exposition will give a speedy outline of how the main vector-borne diseases in India are evolving epidemiologically.

Antimicrobial resistance characterization of Enterococcus faecium, Enterococcus faecalis and Enterococcus hirae isolated from marine coastal recreational waters in the State of São Paulo, Brazil.

Coastal water quality is facing increasing threats due to human activities. Their contamination by sewage discharges poses significant risks to the environment and public health. We aimed to investigate the presence of antibiotic-resistant Enterococcus in beach waters. Over a 10-month period, samples were collected from four beaches in the State of São Paulo (Brazil). Enterococcus isolates underwent matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) and molecular analysis for accurate genus and species identification. The antimicrobial susceptibility for 14 antibiotics was evaluated using the disc diffusion method followed by a multidrug-resistance (MDR) classification. PCR amplification method was used to detect antimicrobial resistance genes (ARGs). Our findings revealed the prevalence of Enterococcus faecalis, E. faecium and E. hirae. Out of 130 isolates, 118 were resistant to multiple antibiotics. The detection of resistance genes provided evidence of the potential transfer of antibiotic resistance within the environment. Our findings underscore the necessity for continuous research and surveillance to enhance understanding of the pathogenicity and antimicrobial resistance mechanisms of Enterococcus, which is crucial to implement effective measures to preserve the integrity of coastal ecosystems.

Diversity and distribution patterns of Sea Urchins (echinoidea) in the waters of Doreng Beach, Sikka Regency, Indonesia

Echinoidea is a marine biota with many important roles in life. Echinoidea can be found in various sea and water areas, one of which is in the waters of Doreng Beach. The rampant exploitation activities and minimal efforts to conserve Echinoidea in the waters of Doreng Beach have caused the diversity of Echinoidea to decline. This study aimed to identify the types of Echinoidea and analyze their abundance and distribution patterns in the waters of Doreng Beach. This research was conducted on October 1 -November 1, 2022. The type of research conducted was qualitative descriptive research with a field observation approach. The method used was the quadrat sampling method. Observations were carried out at three stations, each with 15 quadrat plots measuring 1 x 1 m2. The results of the study showed that there were eight species in the waters of Doreng Beach, namely Echinometra mathei, Echinometra viridis, Diadema setosum, Diadema savignyi, Echinothrix calamaris, Echinothrix diadema, Tripneustes gratilla and Tripneustes Ventricosus. The highest abundance is from the species Echinometra mathei, with a value of 4.62 ind/m2, and the lowest is Diadema savignyi, with a value of 0.02 ind/m2. The distribution pattern of Echinoidea in Doreng Beach Waters is clustered with a moisten index value of 5.5.

Microbial Health Risks of Cryptosporidium parvum and Giardia lamblia in Tropical Coastal Water in Araromi, Nigeria.

Giardia and Cryptosporidium are enteric protozoa that can cause a variety of gastrointestinal diseases, especially in vulnerable people like children, the elderly, and those with impaired immune systems. In order to ascertain the microbiological quality of the recreational water from Araromi Beach in Ilaje Local Government Area, Ondo State, Nigeria. This risk assessment is of great significance to human health protection against waterborne diseases. The aim of this study was to determine the microbial quality of recreational water from Araromi Beach in Ilaje Local Government Area, Ondo State, Nigeria. Microscopic examination of Cryptosporidium and Giardia oocysts were done. Results revealed maximum occurrence of Cryptosporidium parvum (20 oocysts/100 mL) of water sample in the month of April and maximum occurrence of Giardia lamblia (300 cysts/100 mL) of water sample in the month of June. Additionally, according to Kolmogorov-Smirnov tests for normalcy Ho =0.05, Giardia lamblia and Cryptosporidium parvum were not regularly distributed in the water samples collected from the beach throughout the study period. The average likelihood of contracting Giardia lamblia and Cryptosporidium parvum infections after consuming 100 mL of beach water was 0.96 and 0.35, respectively. The risks of infection associated with Cryptosporidium parvum was lower than those associated with Giardia lamblia in water from the beach, but were both above the acceptable risk limit of 10-4. The results of this study indicate that Giardia and Cryptosporidium may represent serious health hazards to people who engage in aquatic activities. Adopting a comprehensive strategy that includes regular inspections, enhanced detection techniques, and the prevention of aquatic environment pollution may provide clean and safe recreational water for all, thereby safeguarding the public's health.

Microplastics in surface water of different beaches in Chattogram coastal area of Bay of Bengal in Bangladesh

Microplastics in surface water of different beaches in Chattogram coastal area of Bay of Bengal in Bangladesh

Essential Mineral Profile of Lingula unguis from Mutiara Beach Waters as a Functional Food Candidate

Essential Mineral Profile of Lingula unguis from Mutiara Beach Waters as a Functional Food Candidate

Seagrass Community Structure in Mangket Beach Water, Kema District, North Minahasa Regency

The purpose of this study was to determine the types of seagrasses, density, relative density, frequency, diversity index, dominance index, and environmental factors in Mangket coastal waters. This research method is the quadratic and line transect. This research was conducted in the waters of Mangket Beach, Kema District, North Minahasa Regency on November 27, 2022. There were 3 species of seagrass found in Mangket Beach waters, namely, Cymodocea rotundata, Cymodocea serrullata, and Enhalus acoroides. The number of seagrass species stands at the study site ranged from 105-814 individuals, species density (4.38-33.92 individuals/m2), relative density (6.54-50.72%), frequency of presence (1.67-4 .00), relative frequency (17.24-41.38%), diversity index H'= (0.38) and dominance index (0.004-0.26). The environmental conditions in the waters are temperature 29.5°C, salinity 32‰, and sandy and sandy mud substrates. Keywords: Mangket Beach, seagrasses, community structures. Abstrak Tujuan penelitian ini adalah untuk mengetahui Struktur Komunitas Lamun meliputi jenis-jenis lamun, kepadatan, kepadatan relatif, frekuensi, frekuensi relatif, indeks keanekaragaman, indeks dominasi dan faktor lingkungan perairan pantai Mangket. Metode penelitian ini adalah kuadrat dan line transek. Penelitian ini dilaksanakan di perairan Pantai Mangket Kecamatan Kema Kabupaten Minahasa Utara pada tanggal 27 November 2022. Spesies lamun yang ditemukan di perairan Pantai Mangket berjumlah 3 yaitu, Cymodocea rotundata, Cymodocea serrullata dan Enhalus acoroides. Jumlah tegakan spesies lamun di lokasi penelitian berkisar dari 105-814 individu, kepadatan spesies (4,38-33,92 individu/m2), kepadatan relatif (6,54-50,72%), frekuensi kehadiran (1,67-4,00), frekuensi relatif (17,24-41,38%), indeks keanekaragaman H’= (0,38) dan indeks dominasi (0,004-0,26). Kondisi lingkungan di perairan yakni suhu 29,5°C, salinitas 32‰, substrat lumpur berpasir dan berpasir. Kata Kunci: Pantai Mangket, lamun, struktur komunitas.

Environmental factors associated with Escherichia coli concentration at freshwater beaches on Lake Winnipeg, Manitoba, Canada

At many public beaches, routine monitoring of beach water quality using fecal indicator bacteria is conducted to evaluate the risk of recreational water illness. Results from water sample analysis can take over 24-hr, which may no longer accurately reflect current water quality conditions. This study aimed to assess which combination of environmental factors best predicts fecal contamination (E. coli) levels at two of the most popular beaches on Lake Winnipeg, Manitoba (Gimli and Grand Beach), by linking water quality data and publicly available environmental data from 2007 to 2021. We developed separate mixed effects models for each beach for two outcomes, linear (continuous log-transformed E. coli concentration) and categorical (200 CFU/100 ml threshold), to explore differences in the predictors of E. coli concentrations and exceedances of the provincial health risk threshold, respectively. We used a Directed Acyclic Graph to choose which predictor variables to include in the models. For both beaches, we identified clustering of the E. coli outcomes by year, suggesting year-specific variation. We also determined that extreme weather days, with higher levels of rainfall in the preceding 48-hr, previous day average air temperature, and previous day E. coli concentration could result in a higher probability of E. coli threshold exceedances or higher concentrations in the water bodies. In Grand Beach, we identified that days with lower average UV levels in the previous 24-hr and antecedent dry days could result in a higher probability of E. coli threshold exceedances or higher concentrations. The findings can inform possible trends in other freshwater settings and be used to help develop real-time recreational water quality predictive models to allow more accurate beach management decisions and warrant enhancement of beach monitoring programs for extreme weather events as part of the climate change preparedness efforts.

Distribution of antibiotic resistant bacteria and genes in sewage and surrounding environment of Tórshavn, Faroe Islands

Several studies have investigated the effects of swimming in sewage-polluted recreational beach water, highlighting the associated health hazards. To mitigate potential pathogen transmission, it is imperative that the polluted water is released away from recreational waters and foreshores, where children tend to play. At present, domestic sewage in the Faroe Islands solely undergoes primary wastewater treatment within primary settling tanks before being discharged into the ocean. Effluents are a major anthropogenic source of antibiotic resistance genes and antibiotic resistant bacteria, which are released into the environment. The aim of this study was to investigate antibiotic resistant Gram-negative bacteria and antibiotic resistance genes in influents and effluents of wastewater subjected solely to primary treatment, along with their release into the environment during both summer and winter. Water samples were collected from influents and effluents as well as with increasing distance away from the wastewater outlet and from nearby tidepools. Samples were cultured on MacConkey agar with four different antibiotics for detection of antibiotic-resistant bacteria and antibiotic resistance genes were quantified by droplet digital PCR. All multi-drug resistant bacteria were identified using the API 20E kit. We observed an overall decrease of the abundance of Gram-negative bacteria from the effluents compared to influents, however, we observed the opposite trend in the antibiotic resistance genes. Antibiotic resistant bacteria and antibiotic resistance genes in addition to multi-drug resistant bacteria were found in the surrounding oceanic and several terrestrial tidepool samples. Of the multi-drug resistant bacteria, we found, e.g., Escherichia coli, P. aeruginosa, and A. hydrophila species, which can be pathogenic, potentially causing an infection if encountering a host. These results indicate a relatively wide pollution range of the effluents from the septic tank and treated sewage released into the environment, posing a potential hazard for both humans and wildlife.

South Carolina Beach Water Quality: Stakeholder Workshop Identifies Challenges, Needs, and Recommendations

Coastal water quality is often identified by diverse stakeholders as a major management challenge but can be difficult to define. South Carolina Beach Advocates (SCBA), a nonprofit organization formed in 2015 to educate the public, governmental authorities, and elected officials as to the environmental, economic, and societal impact of South Carolina's beaches and inlets, recognized this challenge and organized a virtual workshop in June 2022 to explore our beachfront communities' water quality management challenges, and discuss various perspectives on beach water quality. Thirty-eight participants from government agencies, local government, industry, academia, and civic society discussed this important topic and identified challenges and concerns, general requirements, needed new capabilities, and recommendations for next steps. Following the workshop, a Beach Water Quality Subcommittee was formed under the auspices of the SCBA to continue this important conversation.

Assessing the role of tidal cycle, waves, and wind as drivers of surf zone zooplankton on a temperate sandy beach

The surf zone is strongly affected by tides, waves, and winds. However, there are still a lack of knowledge about the response of the zooplankton community to these physical factors in the surf area, with a particular emphasis on tidal effects. The aim of this study was to conduct a preliminary assessment of two distinct tidal cycles, encompassing fluctuations in on-offshore currents, waves, and wind and their influence on the surf zooplankton community of Pehuen Co (PC) sandy beach, Argentina. The study involved field sampling at a single station in the surf zone on September 4th, 2018, and May 20th, 2019. The sampling covered four tidal phases at 3-hour intervals, when water and zooplankton samples were collected for analysis. Environmental variables, such as current velocities, water level, and wind data, among others, were also registered. The results indicated that the abundance of surf zooplankton was significantly influenced by physical forces, resulting in distinct impacts. During the Sept 2018 tidal cycle (calm conditions), an on-offshore current emerged as the primary driving force, resulting in the highest abundance of zooplankton being observed at low tide. In contrast, during the May 2019 tidal cycle (southern winds), strong winds intensified the offshore current velocities and wave height, affecting the zooplankton abundance. High velocities of on-offshore currents corresponded to lower abundance of zooplankton at low tide. This situation introduced an extra physical force -the wind- playing a significant role in restructuring the dynamic of the zooplankton community. The preliminary analysis suggests that the relationship between environmental and biological data is complex and varies depending on the physical factors involved. Notably, in rough conditions, south winds can restructure zooplankton dynamics, influenced by strong winds. This work emphasizes the importance of the surf zone waters of sandy beaches and are useful for future research or monitoring programmes of similar high-energy ecosystems.

Trophic Fish Structure Along the Beaches of The Brazilian Amazon River

Purpose: This study analyzes fish communities' diet and trophic structure on beaches along the Amazon River. Methods: 41 beaches were studied, and fish were collected with 12x3m trawl nets and 5mm mesh between nodes. The stomachs were analyzed using the frequency of occurrence and points method. The dietary index was calculated using the preponderance index (PI). Using IP values, the following trophic categories were established: detritivore, hematophagous, herbivorous, benthic invertivore, pelagic invertivore, terrestrial invertivore, scavenger, and piscivore. Species richness and abundance of fish in trophic categories were related to the longitudinal variation of the sampled sites through linear regression 1,166 stomachs from 119 species were analyzed. Results and discussion: The abundance and richness of detritivore species and the richness of scavengers showed a negative relationship throughout the floodplain, while the number of aquatic invertivore species showed a positive relationship. Implications of the research: The existing differences in beach water quality create a longitudinal conductivity gradient, transparency, and suspended material, gradually altering the environment and composition of the ichthyofauna and the trophic structure along the Amazon River. Originality/value: Ecological studies relating the trophic structure of fish to a large-scale longitudinal gradient are scarce in the Amazon River floodplain, which makes this article an essential piece for better understanding Amazonian systems by characterizing the trophic structure of fish from beaches in a longitudinal gradient of the Amazon River in Brazilian territory.

Beachgoers' responses to beach health advisories.

Drawing on responses from 238 beachgoers who have visited a Georgia (U.S. state) beach in the past three years, this study asks respondents about their knowledge of beach water quality monitoring, awareness of beach health advisories, perception of water quality, and expected responses upon learning of a beach's water pollution advisory. Binomial logistic regression finds that the only demographic predictor of respondents who would completely stop visiting a beach with an advisory is whether the respondent is a visitor or resident (year-round or part-time). Nearly 40% of visitors would not come to a beach with an advisory compared to 13.4% of residents. Most respondents report they would continue to visit a beach but would stay out of the water and stop harvesting seafood from the beach's waters. More than a third (36.1%), however, are unaware Georgia regularly monitors beach water for water quality, and 41.2% have never read a beach sign warning of contaminated water or seafood. Alarmingly, just over half view aesthetic factors such as no litter, no odor, and clear water as criteria for defining whether beach water is safe.

Abudance of demersal fish by longline fishing gear in Sentang Waters, Serdang Bedagai Regency, Sumatera Utara

Demersal fish is the main catch for traditional fishermen using longline fishing gear in Sentang Beach waters located in Serdang Bedagai Regency, North Sumatra Province. The high economic value of demersal fish is the focus of traditional fishermen to make it the main catch. This study aims to determine the composition of the catch and the abundance index of demersal fish caught by longline in the waters of Sentang Beach. The method used in this research is to use a random sampling method with the mechanism of joining fishermen to go to sea for one month every time fishermen go to sea in November 2022. The data analysis technique uses abundance index value analysis and multiple linear regression analysis. The results showed that the composition of demersal fish caught using longline fishing gear consisted of 5 species of fish namely Snapper (Lates calcarife), Threadfins (Eleutheronema tetradactylum), Pomfret (Pampus argenteus), Sagor catfish (Hexanematichthys sagor) and Mullet (Valamugil saheli) with the highest abundance index obtained by the mullet species. Obtained the highest relative relative abudance of fish found in Senangin species which is 100% and the lowest relative relative abudance of fish in the species of Snapper which is 1.14%.

Identification of potential microbial risk factors associated with fecal indicator exceedances at recreational beaches

BackgroundFecal bacterial densities are proxy indicators of beach water quality, and beach posting decisions are made based on Beach Action Value (BAV) exceedances for a beach. However, these traditional beach monitoring methods do not reflect the full extent of microbial water quality changes associated with BAV exceedances at recreational beaches (including harmful cyanobacteria). This proof of concept study evaluates the potential of metagenomics for comprehensively assessing bacterial community changes associated with BAV exceedances compared to non-exceedances for two urban beaches and their adjacent river water sources.ResultsCompared to non-exceedance samples, BAV exceedance samples exhibited higher alpha diversity (diversity within the sample) that could be further differentiated into separate clusters (Beta-diversity). For Beach A, Cyanobacterial sequences (resolved as Microcystis and Pseudanabaena at genus level) were significantly more abundant in BAV non-exceedance samples. qPCR validation supported the Cyanobacterial abundance results from metagenomic analysis and also identified saxitoxin genes in 50% of the non-exceedance samples. Microcystis sp and saxitoxin gene sequences were more abundant on non-exceedance beach days (when fecal indicator data indicated the beach should be open for water recreational purposes). For BAV exceedance days, Fibrobacteres, Pseudomonas, Acinetobacter, and Clostridium sequences were significantly more abundant (and positively correlated with fecal indicator densities) for Beach A. For Beach B, Spirochaetes (resolved as Leptospira on genus level) Burkholderia and Vibrio sequences were significantly more abundant in BAV exceedance samples. Similar bacterial diversity and abundance trends were observed for river water sources compared to their associated beaches. Antibiotic Resistance Genes (ARGs) were also consistently detected at both beaches. However, we did not observe a significant difference or correlation in ARGs abundance between BAV exceedance and non-exceedance samples.ConclusionThis study provides a more comprehensive analysis of bacterial community changes associated with BAV exceedances for recreational freshwater beaches. While there were increases in bacterial diversity and some taxa of potential human health concern associated with increased fecal indicator densities and BAV exceedances (e.g. Pseudomonas), metagenomics analyses also identified other taxa of potential human health concern (e.g. Microcystis) associated with lower fecal indicator densities and BAV non-exceedances days. This study can help develop more targeted beach monitoring strategies and beach-specific risk management approaches.