Tidal Water Research Articles

Red tide detection based on high spatial resolution broad band optical satellite data

Red tide, one of the major ecological disasters in the world, exerts great impact on the marine environment. The ocean color satellite data with low spatial resolution and high spectral resolution is often used for red tide detection, but is insufficient for the fine-scale red tide detection due to its coarse spatial resolution. To address this problem, a new red tide detection method based on pseudo hue angle (PHA-RI) for high spatial resolution broad band satellite data is proposed in this paper. Different from the standard International Commission on Illumination (CIE) system, the false-color bands of near infrared (NIR), red and green are used to calculate the CIE tristimulus X, Y, Z, instead of the true-color bands of red, green and blue. With this method, the red tide can be easily differentiated from non-red tide water, and the distinction between red tide and non-red tide water is doubled compared to that of true-color bands composite. Experiment results show that the PHA-RI method can effectively detect red tide, with an averaged overall accuracy, F1-score and precision of 92%, 0.92 and 0.92 respectively. Compared with the traditional machine learning method support vector machine (SVM) and spectral index algorithm Gaofen-1 (GF-1) red tide detection index (GF-RI), the proposed algorithm has obvious advantages in red tide detection, especially for the strip distributed red tide. Besides, the proposed algorithm has good applicability, and it is proved to be suitable for the detection of red tides with different dominant species including Noctiluca scintillans, Skeletonema costatum and Heterosigma akashiide. Also, it is applicable to different broad band sensors, such as Chinese satellites GF-1 Wide Field of View (WFV), Haiyang 1D (HY-1D) Coastal Zone Imager (CZI), Sentinel-2 MultiSpectral Instrument (MSI) and Landsat 8 Operational Land Imager (OLI). The application experiment indicates that the proposed algorithm is effective in red tide detection, and it can successfully detect fine-scale red tide events, which have not been detected by Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua due to its coarse spatial resolution. The results also shows the advantages of high spatial resolution satellites in fine-scale red tide detection. This work provides a method for red tide detection using high spatial resolution broad band satellite data.

Potential of tidal power plants on Tibo Beach with spektrum method

As time evolved, the demand for electrical energy also increased. As a result, renewable energy is needed to replace fossil fuels as fuel for electricity generation. Tidal water is one of the renewable alternative energy sources used as fuel for electricity generation. The tides will never run out and can also be predicted. One method that can predict data about waves is the Spectrum Method. Tide prediction data can be indicated by carrying out tidal height observations for 15 days at Tibo Beach, Donggala Regency, Central Sulawesi. Based on observations, the data obtained are the highest high water level (HHWL) is 2.4 meters, and the lowest low water level (LLWL) is 0.1 meters. Also, the type of tides on the Tibo coast is a type of mixed waves that tend to double daily, there are two tides with high water and two tides with low water with different water levels. Because the value of formzahl is 0.312. With a 2.4 meter high HHWL and a sea area of 35.4 km2, the electricity generated is 13.08 MW.

Analysis of the inter-annual variability and southward expansion of red tides in the Zhejiang coastal waters from 1981 to 2018

Analysis of the inter-annual variability and southward expansion of red tides in the Zhejiang coastal waters from 1981 to 2018

Tidal water exchange drives fish and crustacean abundances in salt marshes

Coastal salt marshes provide important habitat for fishes and crustaceans, including species of commercial value that feed or take refuge in the marsh. Yet population abundances vary considerably between sites, often without clear explanation. We hypothesised that faunal abundance and mean size would be positively related to 2 physical properties that govern marsh accessibility to water-dependent species, as has been found on the southeastern coast of the USA: (1) the volume of water exchanged by tidal flooding, which gives access to the marsh, and (2) edge amount, the length of the water-vegetation borderline per unit area where species can take refuge and feed. Digital terrain models and tidal information were used to select 5 marshes in Wales, UK, that differed in edge amount and water exchange (52°N, 4°W). Fishes and crustaceans were sampled using baited traps, fyke nets and seine nets. In total, 15 species were caught, including commercially valuable brown shrimp, European eel and sea bass. We found water exchange volume, but not edge amount, boosted fish and crustacean abundances. Crab and sea bass sizes were both negatively affected by water exchange, while shrimp and fish sizes were unaffected. Our findings show how the mechanisms that drive fish and crustacean abundances and sizes vary between geographical regions. Feasibly, fisheries associations with marsh hydrogeomorphology might operate differently as well.

The structure community of zooplankton and environmental conditions of the Kalimireng River estuary, Gresik, East Java

Water quality monitoring is a key component in the management of these important water resources and ecosystems. Biological indicators can be monitored continuously and are easy instructions for monitoring the occurrence of pollution. One of the biological parameters that can be used as a marker of environmental conditions is plankton. zooplankton can be used as study material to determine the quality and water productivity. The method used in this research is descriptive to determine the water quality condition in the estuary of the Kalimireng river biologically through the identification and characterization of zooplankton. Observations of plankton identification, plankton abundance, dominance index, and characterization of zooplankton were analyzed by fluorescence microscope observation. Three species of zooplankton were found in the waters of the Kalimireng estuary, Leptodiaptomus sp., Canthocamptus staphylinus, and Diaphanosoma bracyurum. Zooplankton is more abundant in water conditions at high tide compared to water conditions at low tide. At high tide, the highest abundance value was obtained at the station I at week 3, 843 ind/mL. At low tide, the highest abundance value was obtained at the station I at week 2,251 ind/L. The highest Dominance Index (D) at tidal water conditions is shown at station 2. This indicates that there is a community that dominates at that station.

Establishing a long-term Tidal Water Elevation for Thane City, India

Future extreme tide levels and flood risk along the coastal region will be impacted strongly by climate change. Flooding in urban areas is a big challenge affecting coastal cities worldwide due to heavy rainfall coupled with high tides. The key factor in the design and planning of coastal town drainage systems is the selection of appropriate tide levels at drainage outfall location. The present study aims to define the long-term tidal water level for Thane city, India and this level will perform effectively under current and future tidal water conditions. The present study uses the observed tidal data from 2009 to 2018 about Thane Salt Bundar tide gauge station and Kasheli Bridge tide gauge station. Initially, the tidal levels are defined for various tidal phases using the fundamental statistical analysis method, the trend of tide level analysed by the linear regression model and then Gumbel's extreme value type I (EV-I) distribution method used to define the long-term tide levels for different return periods. The obtained results indicate that the tidal level may rise by 300 mm at Thane salt bundar and 270 mm at Kasheli bridge. The long-term tidal level at Thane salt Bundar may increase 3.3m and 2.3 m at Kasheli bridge. Established long-term tidal levels give good results under climate change conditions and can be safer for avoiding flood risk and improving the drainage outfall design for Thane city.

Calibration of a 3D hydrodynamic model for a hypertidal estuary with complex irregular bathymetry using adaptive parametrization of bottom roughness and eddy viscosity

This study introduces a new scheme to make both turbulence and flow resistance modeling a dynamic function of tidal water depths and flow direction. The k−ε turbulence model is continuously adapted to local depth conditions and the Manning n bed roughness values are continuously made locally dependent on the direction of flow. Turbulence structure, production, and attenuation in estuaries are highly influenced by the fact that the flow occurs in ‘shallow water’. In hypertidal estuaries with complex bathymetries, the depths are highly variable in both time and space. In this paper, an adaptive correction scheme is introduced to dynamically adjust (in time and space) the k−ε turbulence model as a function of local flow depth. Furthermore, in the flow reversal portions of tidal rivers, flow direction changes cyclically during flood tides and ebb tides. This causes a direction-based pattern of bedforms that significantly affects the directional values of hydrodynamic bed resistance (Manning n). In this paper, an adaptive scheme accounts for flow directionality. The modifications are incorporated into a three-dimensional numerical hydrodynamic model (Delft3D). The resulting simulated water levels of the Koksoak hypertidal estuary are presented and are demonstratively in better agreement with observations than water levels simulated when not using the corrections. The results suggest that the proposed schemes can improve the accuracy of the turbulence and bed roughness models for simulations of shallow hypertidal estuarine flows with complex river bathymetries.

Mangrove leaves: An undeniably important sink of MPs from tidal water and air

Capturing microplastics (MPs) were one of the important characteristics for terrestrial plant. Whereas, role of mangrove leaves in capturing MPs from tidal water and air were still largely unexplored. Here, we detected the spatial distribution of MPs at both submerged (0.10-0.49 n/cm2) and non-submerged mangrove leaves (0.09-0.24 n/cm2) in the Beibu Gulf. Abundance of MPs on submerged mangrove leaves was significantly higher than that on non-submerged mangrove leaves in landward and middle zone (*p < 0.05). Almost no difference existed in the abundances of MPs detected on leaves of different mangrove species. Abundance of MPs on submerged mangrove leaves increased following the sequences of seaward zone (0.11 n/cm2) < middle zone (0.21 n/cm2) < landward zone (0.36 n/cm2). PE MPs with uncoloured/fiber characteristics dominated the MPs both on the non-submerged and submerged mangrove leaves. Furthermore, contribution of tidal water was significantly greater than that of atmospheric deposition on MPs retention on submerged mangrove leaves. Results of this work highlight the importance of tidal water and air in the spatial distribution of MPs at mangrove leaves, and the globally MPs gross reserves at mangrove leaves cannot be ignored in evaluating the MPs sink in mangrove wetland.

Study of Situational Disaster Nursing in Community Preparedness for Tidal Water Disaster in Bahagia Village Pangkal Babu, Tanjung Jabung Barat Regency

Safe Community is a condition that is expected to guarantee a sense of security and health of the community by involving the active role of the entire community, especially in dealing with daily emergencies and during disasters. Bahagia Village has a high risk of tidal water disaster but has never been touched by preparedness disaster from the government, while the significant obstacles are diarrheal disease and common skin disease. there is no provision of counseling or motivating the community to prepare for disaster management. In Tanjung Jabung Barat Regency, there are 3 districts that are prone to disasters, one of which is Tungkal Ilir District 1. Tungkal Ilir 1 District is geographically located on the high seas and within a radius of 1 km from the sea. Based on the BNPB's RBI (Indonesian Disaster Risk) study, land within a radius of 2 km from the sea has a greater risk of disaster with various potential disasters. In the last 10 years, there have been at least 5 tidal water disasters in Tungkal Ilir 1 District, especially in Bahagia Village. This condition underlies the need for a situational study of disaster preparedness in Tanjung Jabung Barat Regency to improve disaster risk reduction (DRR) efforts in order to create a rural-based safe community. This study aims situational state of disaster nursing preparedness of the community around the tidal area in order to realize a disaster preparedness village. This research was conducted with a quantitative survey analysis research with a combination of phenomenological approaches. The sample in this study are 60 respondents, the sampling technique known as purposive sampling. the parameters measured are the level of knowledge, policies and guidelines, emergency response plans, resource mobilization, and disaster warnings. Parameters are measured by disaster preparedness scores. The results of this study show that based on the disaster preparedness score, Bahagia Village community has classified as very ready on knowledge parameter (80,06%),as not ready on policies and guidelines parameter (12,08%), as less ready on emergency response plan parameter (41,83%), as less ready on disaster warning (48,45%), and as not ready on mobilization resources parameter (16,67%).

Assessing the role of deltaic flood plain wetlands on regulating methane and carbon balance

Present study deals with the role of wetland for regulating greenhouse gases (GHG) particularly methane (CH4) emission and carbon (C) sequestration in mature Ganges deltaic environment. The annual total amount of emission and sequestration in wetlands of varying types was estimated along with the seasonal variation. Result showed that the streams were the highest emitter of CH4 followed by ox-bow lakes in all the seasons whereas the bheries (embanked pisciculture arresting tidal water) consistently exhibited the lowest average emission. The average sequestration of C was the highest in ox-bow lakes followed by marshes and mudflats. The average emission in monsoon season was 43% and 78% higher than the average emission of pre and post-monsoon seasons respectively. The yearly total emission was 8.01 × 103 ton and yearly total sequestration was estimated 908.98 × 103 ton. From the perspective of GHG regulation, the wetlands were found to yearly uptake four times higher carbon dioxide (CO2) than the CO2 equivalent (CO2e) of emitted CH4. After offsetting the fixation cost of emitted CH4, the yearly surplus sequestrated C in the wetlands of the entire region was worthy of 68.46 million US dollar (USD). So, wetland plays positive role for reducing greenhouse gas effect and associated temperature rise which is considered to be serious issue. Such result has made a good agreement on the debated issue of wetland CH4 emission and C sequestration and will encourage restoring wetland for even mediating GHG issue.

PELUANG URBAN FARMING UNTUK MENINGKATKAN KETAHANAN PANGAN WILAYAH RENTAN BANJIR DI KELURAHAN BANDENGAN KOTA PEKALONGAN

&lt;p&gt;Bandengan village is one of the northern coastal areas of Pekalongan which has been affected by tidal flooding until now. The tidal flood conditions forced people whose livelihoods were from agriculture to change into casual laborers, traders and so on. There is a need for technological breakthroughs in carrying out agricultural activities that are minimal and unsupportive. The modern term that is currently used to cover several cultivation methods in urban areas is Urban Farming. Urban Farming is a form of urban farming growing food in urban areas on land, usually in backyards or on vacant lots, but sometimes neglected spaces such as road medians, which are not usually dedicated to producing food. Extension activities and mentoring by competent agriculture can be able to change conditions that are less favorable for agricultural cultivation until the community is ready in terms of theory and practice. This service is in the context of the 40th anniversary of Pekalongan University in the context of forming the target village. The methods used in this service are lectures, active participation or discussion and mentoring. The outreach activities in the form of lectures and discussions were attended by the youth of the Bandengan village. An overview of Urban Farming is presented using a projector. The explanation of the Urban Farming concept offered is in accordance with the Bandengan area (verticulture, hydroponics, aquaponics and polybags) and what has been done by Bandengan residents, namely hydroponics and polybags. The implementation of this counseling has an impact on the community's enthusiasm to carry out agricultural activities even though their agricultural land has been submerged by tidal water. Urban farming explains how cultivation on land is limited and affected by tidal flooding but can still produce vegetable and fruit crops that can increase the income of the people of Bandengan village.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords&lt;/strong&gt; : Agriculture, Bandengan, Flood Rob, Urban Farming&lt;/p&gt;

Vegetation and hydrology stratification as proxies to estimate methane emission from tidal marshes

Direct measurement of methane emissions is cost-prohibitive for greenhouse gas offset projects, necessitating the development of alternative accounting methods such as proxies. Salinity is a useful proxy for tidal marsh CH4 emissions when comparing across a wide range of salinity regimes but does not adequately explain variation in brackish and freshwater regimes, where variation in emissions is large. We sought to improve upon the salinity proxy in a marsh complex on Deal Island Peninsula, Maryland, USA by comparing emissions from four strata differing in hydrology and plant community composition. Mean CH4 chamber-collected emissions measured as mg CH4 m−2 h−1 ranked as S. alterniflora (1.2 ± 0.3) ≫ High-elevation J. roemerianus (0.4 ± 0.06) > Low-elevation J. roemerianus (0.3 ± 0.07) = S. patens (0.1 ± 0.01). Sulfate depletion generally reflected the same pattern with significantly greater depletion in the S. alterniflora stratum (61 ± 4%) than in the S. patens stratum (1 ± 9%) with the J. roemerianus strata falling in between. We attribute the high CH4 emissions in the S. alterniflora stratum to sulfate depletion likely driven by limited connectivity to tidal waters. Low CH4 emissions in the S. patens stratum are attributed to lower water levels, higher levels of ferric iron, and shallow rooting depth. Moderate CH4 emissions from the J. roemerianus strata were likely due to plant traits that favor CH4 oxidation over CH4 production. Hydrology and plant community composition have significant potential as proxies to estimate CH4 emissions at the site scale.

Numerical simulations of compound flooding caused by storm surge and heavy rain with the presence of urban drainage system, coastal dam and tide gates: A case study of Xiangshan, China

Nowadays, most coastal cities have complex drainage systems (i.e., rivers and pipelines) connected to the sea, affecting the flooding during the co-occurrence of rain and storm surges. In this study, this compound flooding is studied by developing a coupled model based on a one-dimensional (1D) hydrological model SWMM and a two-dimensional (2D) hydrodynamic model ADCIRC. The coupling is achieved by setting the 1D model as a subroutine of the 2D model while the parallel computing scheme of the 2D model is kept using the Message Passing Interface (MPI). The coupled model is applied in Xiangshan, Zhejiang Province, along the eastern coast of China. The model accurately ensures water conservation and reproduces the observed tidal elevation, storm surge, and river water stages during Typhoons Haikui (2012) and Fitow (2013). A series of simulations are carried out to quantify the influences of coastal dams, drainage systems, control of tide gates, rain, and storm surges on the compound flooding. The results show that the drainage system enhances the connectivity between the land and the sea no matter whether the coastal dam exists, leading to faster flooding and draining. Furthermore, when a storm surge occurs, the high surge level can significantly reduce the drainage efficiency of the inland flooding during rain and thus causes more severe flooding hazards. The simulation results also suggest that urban pipelines play an important role in preventing urban flooding caused by rain. And for the prevention of storm surge inundation, an effective gate control strategy is suggested that the gates should be closed when the water levels on both sides of the dam are equal for the first time before the peak of the storm surge and are open when the water levels are equal again. Finally, the flooded area can be divided into the tidal zone, the hydrologic zone, and the transition zone to identify different flood mitigation strategies.

Distribution of Tide Type in Indonesian Waters Based on 7 Days Data Measurement of Ipasoet-BIG Station

Tidal data is needed in the field of energy, marine navigation, coastal construction and other activities related to the oceans. Tidal phenomena occur due to the interaction of the earth with space objects. The sea level rise in coastal waters can be modeled by a harmonic function containing tidal constant numbers. From the constants formed can be calculated a Formzahl number that shows the type of tides that occur at the observation station. This paper tries to describe the distribution pattern of tidal types that exist in Indonesian waters based on data observation collected at station belong to the Geospatial Information Agency. The result is that there are 4 types of tides in Indonesian waters, with the most dominant distribution are mixed tide, prevailing semi diurnal typel.

Vertical pore pressure variations and geotechnical sediment properties at a sandy beach

The role of geotechnical properties and soil behavior for beach dynamics has been recognized before, but geotechnical field measurements in energetic beach environments are still rare. This study focused on two days of field measurements along a cross-shore transect reaching from the foot of the dunes to the upper subtidal zone at the western sandy beach of the island of Sylt, Germany, just south of the city of Westerland. Sediment properties and geotechnical parameters were obtained from sediment sampling and limited in-situ testing. Pore pressure measurements were conducted along a vertical array in the upper 55 cm of the beach surface in the lower intertidal zone. Pore pressure recordings were then analyzed using a one-dimensional-vertical (1DV) model based on Biot (1956) and Mei and Foda (1981). Laboratory testing results demonstrated slight trends of increasing grain size and friction angles from the subaerial to the lower intertidal zone. In-situ sediment strength testing using a portable free fall penetrometer supported the trends in friction angles for the subaerial and intertidal zone. Additionally, a significant increase in sediment resistance was observed in the swash zone and upper subtidal zone. Pore pressure recordings showed a consistent trend associated with the tidal water elevations. However, data collected during low tide suggested a decoupling of surface water effects and groundwater, possibly associated with gas content and negative pore pressures in the vadose zone. Pore pressure recordings also suggested a more pronounced wave damping in the upper sediment layers and a minor phase lag. The 1DV pore pressure model succeeded to simulate the observed pressures at all sediment depths well, and suggested no liquefaction events during the measurement period, but a reduction of effective weight that may affect sediment dynamics.

Influence of Edaphic Salinity on Leaf Morphoanatomical Functional Traits on Juvenile and Adult Trees of Red Mangrove (Rhizophora mangle): Implications with Relation to Climate Change

Rhizophora mangle L. is one of the most distributed species of neotropical mangroves. The species exhibits great phenological variability that is associated with saline concentrations of the sediment where it grows. Among the organs that are most affected by interstitial and tidal water salinity concentrations are the leaves. Since the hypersalinity generates water deficiency, it changes photosynthetic and hydraulic processes of the plant. To understand the relationship between the variation in leaf blade parameters and the water stress generated by salinity in two growth stages, morphoanatomical functional traits were quantified in leaves of juveniles and adults of R. mangle in three structurally different mangrove forests with different ranges of natural salinity (Oligohaline: 5.8–11.7 practical salinity units (PSU); Euhaline: 9.2–35.6 PSU and 23.9–47.7 PSU). We hypothesized that water stress caused by salinity generates modification in conductivity, water-storage, and photosynthetic tissues. Our results showed a greater number of morphoanatomical traits affected by salinity in juveniles compared to adults, greater variability in the traits associated with water accumulation and transport. Adults and juveniles subjected to higher values of salinity had traits more tolerant of variability in this factor, allowing superior adaptation to environments with high water deficit than individuals originating in oligohaline environments. This difference in adaptability to salinity between populations of R. mangle may imply different responses to climate change, where populations of oligohaline origin will be more susceptible to hypersalinization resulting from this phenomenon, while populations of euhaline origin could more effectively tolerate the aquatic stresses caused, allowing a prolongation of their permanence and the provision of their ecosystem services over time.

Distribution, sources, and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in the tidal creek water of coastal tidal flats in the Yellow River Delta, China

The concentrations, distribution, sources and ecological risk levels of polycyclic aromatic hydrocarbons (PAHs) in tidal creek water from coastal tidal flats of the Yellow River Delta were investigated. The concentrations of 16 PAHs ranged from 0.113 to 1.533, with a mean value of 0.496 ± 0.035 μg L−1, which indicated a moderate level of pollution. The main long-term sources of PAHs in the coastal tidal flats of the Yellow River Delta were petroleum combustion and petroleum pollution. The ecological risk assessment showed that the levels of PAHs in tidal creek water of the coastal tidal flats in the Yellow River Delta corresponded to medium to high ecological risk levels, and a high probability of potential ecological risk, posing harm to aquatic organisms. Among the 7 sampling sites, site 5, site 6, and site 7 were at high ecological risk, and the other sites were at moderate ecological risk. PAH pollution in the tidal creek water near the Yellow River Estuary and farther south, in the coastal tidal wetland of Laizhou Bay, deserves special attention, especially with respect to the prevention and control of benzo[a]pyrene (BaP) pollution in the water.

Deciphering long-term seasonal and tidal water quality trends in the Mahanadi estuary

Deciphering long-term seasonal and tidal water quality trends in the Mahanadi estuary

Recent trends in inland water level change in coastal Bangladesh–implications of sea level rise in low-lying deltas

Accurately constraining local variation in tidal water levels is the vital first step in managing the risk of coastal hazards associated with sea level rise (SLR). Here we show sub-regional patterns in delta tidal dynamics and coastal SLR along the northern Bay of Bengal based on long-term (1990 to 2017) in-situ measurement data. Seasonal trend decomposition combined with robust linear modelling are applied to determine rates of water level change, with an average rise in coastal extreme sea levels of 6.9 ± 2.1 mm yr−1 translating to increases of 5.1 ± 4.2 mm yr−1 in tidal water levels within the delta. Mean increases of 18.3 ± 4.1 mm yr−1 and 18.2 ± 6.8 mm yr−1 at high and low-tide respectively in tidally dominated rivers of southwest Bangladesh contrast with the fluvially active central and eastern sections of the delta where falling trends of −6.5 ± 2.3 mm yr−1 (high-tide) and −10.2 ± 3.1 mm yr−1 (low-tide) are recorded. Rapid changes in river level at individual sites can occur over periods of ca. 3 to 10 years, most likely resulting from short-term hydro-morphological changes. An acceleration of change in high-tides is indicated by a rise from the long term (1950 to 2018) rate of 4.4 ± 1.5 mm yr−1 to 5.9 ± 3.2 mm yr−1 between 1990 and 2017, leading to increased risk for the local population. At local and regional scales, the inland impact of SLR within the delta is observed to be strongly modulated, necessitating more detailed analysis of driving mechanisms at the site specific level. Our results can be used to aid development of adaptation strategies in Bangladesh and as a call for increased monitoring of hydro-morphological parameters within the Bengal delta and other large deltas in Asia and worldwide.

Investigation of polyethylene terephthalate (PET) drinking bottles as marine reservoirs for fecal bacteria and phytoplankton

Polyethylene terephthalate (PET) is frequently used in the food and beverage industry and therefore contributes greatly to plastic marine debris. The fecal pollution indicator bacteria Enterococcus is used for marine water contamination assessments and is regularly found in storm water discharge. In order to examine if PET drinking bottles act as refuges for Enterococcus, a study was conducted within euhaline tidal waters of Wrightsville Beach, NC, USA via the deployment of bottle floats positioned nearby two stormwater outfall pipes. Bottles were retrieved weekly to assess the accumulation of fecal bacteria and phytoplankton. Each bottle was analyzed for the presence of Enterococcus on plastic surfaces and within water inside the bottle. Abundance of Enterococcus and planktonic chlorophyll α was found to be significantly greater in association with PET bottles versus the surrounding waters. Bottles were observed to act as reservoirs for both Enterococcus and phytoplankton with concentrations well above the state, federal, and WHO standards.