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Whipple, A.; Grossinger, R. M.; Rankin, D.; Stanford, B.; Askevold, R. A. 2012. Sacramento-San Joaquin Delta Historical Ecology Investigation: Exploring Pattern and Process. SFEI Contribution No. 672. SFEI: Richmond.

The Sacramento-San Joaquin Delta has been transformed from the largest wetland system on the Pacific Coast of the United States to highly productive farmland and other uses embodying California’s water struggles. The Delta comprises the upper extent of the San Francisco Estuary and connects two-thirds of California via the watersheds that feed into it. It is central to the larger California landscape and associated ecosystems, which will continue to experience substantial modification in the future due to climate change and continued land and water use changes. Yet this vital ecological and economic link for California and the world has
been altered to the extent that it is no longer able to support needed ecological functions. Approximately 3% of the Delta’s historical tidal wetland extent remains wetland today; the Delta is now crisscrossed with agricultural ditches replacing the over 1,000 miles of branching tidal channels.

Imagining a healthy Delta ecosystem in the future and taking bold, concrete steps toward that future requires an understanding and vision of what a healthy ecosystem looks like. For a place as extensive, unique, and modified as the Delta, valuable knowledge can be acquired through the study of the past, investigating the Delta as it existed just prior to the substantial human modifications of the last 160 years. Though the Delta is irrevocably altered, this does not mean that the past is irrelevant. Underlying geologic and hydrologic processes still influence the landscape, and native species still ply the waters, soar through the air, and move across the land. Significant opportunities are available to strategically reconnect landscape components in ways that support ecosystem resilience to both present and future stressors.

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Wheeler, M.; Stoneburner, L.; Spotswood, E.; Grossinger, R.; Barar, D.; Randisi, C. 2022. An Urban Forest Master Plan for East Palo Alto. SFEI Contribution No. 1071. San Francisco Estuary Institute: Richmond, CA.
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Weston, D. P. 1996. Further Development of Chronic Ampelisca Abdita Bioassay as an Indicator of Sediment Toxicity. SFEI Contribution No. 17. San Francisco Estuary Institute: Richmond, CA.
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Werme, C. 2012. Estuary News RMP Insert 2012. Estuary News. San Francisco Estuary Institute: Richmond, CA.
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Werbowski, L. M.; Gilbreath, A.; Munno, K.; Zhu, X.; Grbic, J.; Wu, T.; Sutton, R.; Sedlak, M.; Deshpande, A. D.; Rochman, C. M. 2021. Urban Stormwater Runoff: A Major Pathway for Anthropogenic Particles, Black Rubbery Fragments, and Other Types of Microplastics to Urban Receiving Waters. Environmental Science and Technology Water . SFEI Contribution No. 1040.

Stormwater runoff has been suggested to be a significant pathway of microplastics to aquatic habitats; yet, few studies have quantified microplastics in stormwater. Here, we quantify and characterize urban stormwater runoff from 12 watersheds surrounding San Francisco Bay for anthropogenic debris, including microplastics. Depth-integrated samples were collected during wet weather events. All stormwater runoff contained anthropogenic microparticles, including microplastics, with concentrations ranging from 1.1 to 24.6 particles/L. These concentrations are much higher than those in wastewater treatment plant effluent, suggesting urban stormwater runoff is a major source of anthropogenic debris, including microplastics, to aquatic habitats. Fibers and black rubbery fragments (potentially tire and road wear particles) were the most frequently occurring morphologies, comprising ∼85% of all particles across all samples. This suggests that mitigation strategies for stormwater should be prioritized. As a case study, we sampled stormwater from the inlet and outlet of a rain garden during three storm events to measure how effectively rain gardens capture microplastics and prevent it from contaminating aquatic ecosystems. We found that the rain garden successfully removed 96% of anthropogenic debris on average and 100% of black rubbery fragments, suggesting rain gardens should be further explored as a mitigation strategy for microplastic pollution.

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Weinstein, A.; Cohen, A. N. 1998. The potential distribution and abundance of zebra mussels in California. Dreissena! (New York Sea Grant) 9, 1-3 . SFEI Contribution No. 323.
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Warner, J. C.; Burau, J. R.; Schoellhamer, D. H. 1997. A sediment transport pathway in the back of a nearly semienclosed subembayment of San Francisco Bay, California. Environmental and Coastal Hydraulics: Protecting the Aquatic Habitat(Proceedings of Theme B., F.M. Holly, A. Alsaffar, S.S.Y. Wang, T. Carstens eds.) 2, 1096-1101 . SFEI Contribution No. 29.
Wang, M.; Kinyua, J.; Jiang, T.; Sedlak, M.; McKee, L. J. .; Fadness, R.; Sutton, R.; Park, J. - S. 2022. Suspect Screening and Chemical Profile Analysis of Storm-Water Runoff Following 2017 Wildfires in Northern California. Environmental Toxicology and Chemistry . SFEI Contribution No. 1089.

The combustion of structures and household materials as well as firefighting during wildfires lead to releases of potentially hazardous chemicals directly into the landscape. Subsequent storm-water runoff events can transport wildfire-related contaminants to downstream receiving waters, where they may pose water quality concerns. To evaluate the environmental hazards of northern California fires on the types of contaminants in storm water discharging to San Francisco Bay and the coastal marine environment, we analyzed storm water collected after the northern California wildfires (October 2017) using a nontargeted analytical (NTA) approach. Liquid chromatography quadrupole time-of-flight mass spectrometric analysis was completed on storm-water samples (n = 20) collected from Napa County (impacted by the Atlas and Nuns fires), the city of Santa Rosa, and Sonoma County (Nuns and Tubbs fires) during storm events that occurred in November 2017 and January 2018. The NTA approach enabled us to establish profiles of contaminants based on peak intensities and chemical categories found in the storm-water samples and to prioritize significant chemicals within these profiles possibly attributed to the wildfire. The results demonstrated the presence of a wide range of contaminants in the storm water, including surfactants, per- and polyfluoroalkyl substances, and chemicals from consumer and personal care products. Homologs of polyethylene glycol were found to be the major contributor to the contaminants, followed by other widely used surfactants. Nonylphenol ethoxylates, typically used as surfactants, were detected and were much higher in samples collected after Storm Event 1 relative to Storm Event 2. The present study provides a comprehensive approach for examining wildfire-impacted storm-water contamination of related contaminants, of which we found many with potential ecological risk. Environ Toxicol Chem 2022;00:1–14. © 2022 SETAC

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Vuckovic, D.; MacDonald, J. A.; Lin, D.; Méndez, M.; Miller, E.; Mitch, W. 2023. Pharmaceuticals, pesticides, and ultraviolet filters in wastewater discharges to San Francisco Bay as drivers of ecotoxicity. Environmental Pollution 336 . SFEI Contribution No. 1153.

Research in the United States evaluating ecotoxic risk to receiving waters posed by contaminants occurring in wastewater discharges typically has focused on measurements of pharmaceuticals and personal care products (PPCPs), with limited evaluations of UV filters and phenylpyrazole and neonicotinoid pesticides. In this study, concentrations of 5 representative pharmaceuticals, 11 pesticides or pesticide degradation products, and 5 ultraviolet filters were measured in 24 h composite samples of six wastewater discharges representing ∼70% of the total wastewater discharged to San Francisco Bay during the summer and fall of 2021. No significant difference was observed between concentrations measured on weekdays vs. weekends. A hydrodynamic model of San Francisco Bay was used to estimate annual average dilution factors associated with different subembayments. With and without considering dilution effects, Risk Quotients were calculated using the 90th percentile of measured concentrations in wastewater effluents and threshold concentrations associated with ecotoxicity. Risk Quotients were highest for the neonicotinoid pesticide, imidacloprid, and exceeded ecotoxicity thresholds in the lower South Bay by a factor of 2.4, even when considering dilution. Compared to commonly measured pharmaceuticals, Risk Quotients for imidacloprid were higher than those for carbamazepine, trimethoprim and diclofenac, and comparable to those for propranolol and metoprolol. Risk Quotients for the pesticide, fipronil, and the UV filter, oxybenzone, were higher than for carbamazepine. The results highlight the need to incorporate pesticides and UV filters with high Risk Quotients into studies in the United States evaluating ecotoxic risk associated with contaminants in municipal wastewater discharges.

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Vaughn, L. Smith; Panlasigui, S.; Spotswood, E. 2020. Livestock grazing and its effects on ecosystem structure, processes, and conservation. SFEI Contribution No. 1011. San Francisco Estuary Institute: Richmond, CA.
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Vaughn, L. Smith; Safran, S.; Robinson, A.; Whipple, A.; Richey, A.; Grenier, L.; Cloern, J.; Andrews, S.; Boyer, K.; Drexler, J.; et al. 2020. Delta Landscapes Primary Production: Past, Present, Future. SFEI Contribution No. 988. San Francisco Estuary Institute: Richmond, CA.

This report describes the Delta Landscapes Primary Production project, which quantifies how landscape change in the Delta has altered the quantity and character of primary production. Combining historical and modern maps with simple models of production for five dominant plant and algae groups, we estimate primary production across the hydrologically connected Delta. We evaluate changes in primary production over time (between the early 1800s and early 2000s), between wet and dry years, and with future targets for landscape-scale restoration. For managers in the Delta, restoring historical patterns of primary productivity is a means to better support native fish and other wildlife. To better equip decision makers in managing for improved primary production, this study offers historical context and the best available science on the relative production value of habitat types and their configurations. 

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Vaughn, L. Smith; Plane, E.; Harris, K.; Robinson, A.; Grenier, L. 2022. Leveraging Wetlands for a Better Climate Future: Incorporating Blue Carbon into California's Climate Planning. SFEI Contribution No. 1084. San Francisco Estuary Institute: Richmond, CA. p 31.

The 2022 update to California’s climate change Scoping Plan incorporates management actions in the state’s forests, shrublands/chaparral, grasslands, croplands, developed lands, deltaic wetlands, and sparsely vegetated lands. Missing from this list are the tidally-influenced coastal ecosystems outside the Sacramento-San Joaquin Delta. These blue carbon ecosystems support high rates of carbon storage and sequestration while providing many co-benefits that can enhance coastal climate change resilience. With sufficient data and robust modeling approaches, California has the opportunity to incorporate blue carbon in future Scoping Plan updates and set actionable targets for restoration, migration space conservation, and other management activities that promote long-term survival of the state’s coastal wetlands. To support this goal, this report offers a high-level overview of the state of the science for blue carbon quantification in California. This summary, which covers datasets and quantification approaches, key focus areas for additional science investment, and example scenarios for coastal wetland restoration, is intended to facilitate broader inclusion of blue carbon in future Scoping Plan updates and other state-level climate-planning documents.

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Vasey, M.; Callaway, J.; Parker, T. V. 2002. Data Collection Protocol Tidal Wetland Vegetation. SFEI Contribution No. 279. San Francisco State: San Francisco, CA. p 13.
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Trowbridge, P.; Davis, J. A.; Wilson, R. 2015. Charter: Regional Monitoring Program for Water Quality in San Francisco Bay. SFEI Contribution No. 750. San Francisco Estuary Institute: Richmond, Calif.

The overarching goal of the RMP is to collect data and communicate information about water quality in San Francisco Bay in support of management decisions. The RMP was created in 1993 through Regional Board Resolution No. 92-043 that directed the Executive Officer to implement a Regional Monitoring Plan in collaboration with permitted dischargers pursuant to California Water Code, Sections 13267, 13383, 13268, and 13385. The goal was to replace individual receiving water monitoring requirements for dischargers with a comprehensive Regional Monitoring Program.

The Program is guided by a Memorandum of Understanding (MOU) between the Regional Board and SFEI, first approved in 1996 and amended at various times since (see Appendix C of this Charter). Section VIII of the MOU states the roles and responsibilities of the Regional Board and SFEI in the implementation of the Program. Participating dischargers pay fees to the Program to comply with discharge permit requirements. The cost allocation schedule for Participants is described in Appendix B. The RMP provides an open forum for a wide range of Participant Groups and other Interested Parties to discuss contaminant issues, prioritize science needs, and monitor potential impacts of discharges on the Bay.

In support of the overarching goal described above, the following guiding principles define the intentions and expectations of RMP Participants. Implementation of the RMP will:

  • Develop sound scientific information on water quality in the Bay;
  • Prioritize funding decisions through collaborative discussions;
  • Conduct decision-making in a transparent manner that consistently represents the diversity of RMP Participant interests;
  • Utilize external science advisors for guidance and peer review;
  • Maintain and make publicly available the data collected by the Program;
  • Enhance public awareness and support by regularly communicating the status and trends of water quality in the Bay; and
  • Coordinate with other monitoring and scientific studies in the Bay-Delta region to ensure efficiency.
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Trowbridge, P.; Wong, A.; Davis, J.; Ackerman, J. 2018. 2018 RMP Bird Egg Monitoring Sampling and Analysis Plan. SFEI Contribution No. 891. San Francisco Estuary Institute: Richmond, CA.
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Trowbridge, P. 2017. Charter: Regional Monitoring Program for Water Quality in San Francisco Bay. SFEI Contribution No. 844. San Francisco Estuary Institute : Richmond, CA.
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Trowbridge, P. 2017. 2018 RMP Detailed Workplan and Budget. San Francisco Estuary Institute : Richmond, CA.
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Trowbridge, P. 2018. Status & Trends Monitoring Design: 2018 Update. San Francisco Estuary Institute : Richmond, CA.
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Trowbridge, P.; Sun, J.; Franz, A.; Yee, D. 2017. 2017 Margins Sediment Cruise Plan. SFEI Contribution No. 847. San Francisco Estuary Institute : Richmond, CA.
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Trowbridge, P. 2018. 2018 Bay RMP Multi-Year Plan. SFEI Contribution No. 860. San Francisco Estuary Institute : Richmond, CA.
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Trowbridge, P. R.; Davis, J. A.; Mumley, T.; Taberski, K.; Feger, N.; Valiela, L.; Ervin, J.; Arsem, N.; Olivieri, A.; Carroll, P.; et al. 2016. The Regional Monitoring Program for Water Quality in San Francisco Bay, California, USA: Science in support of managing water quality. Regional Studies in Marine Science 4.

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) is a novel partnership between regulatory agencies and the regulated community to provide the scientific foundation to manage water quality in the largest Pacific estuary in the Americas. The RMP monitors water quality, sediment quality and bioaccumulation of priority pollutants in fish, bivalves and birds. To improve monitoring measurements or the interpretation of data, the RMP also regularly funds special studies. The success of the RMP stems from collaborative governance, clear objectives, and long-term institutional and monetary commitments. Over the past 22 years, high quality data and special studies from the RMP have guided dozens of important decisions about Bay water quality management. Moreover, the governing structure and the collaborative nature of the RMP have created an environment that allowed it to stay relevant as new issues emerged. With diverse participation, a foundation in scientific principles and a continual commitment to adaptation, the RMP is a model water quality monitoring program. This paper describes the characteristics of the RMP that have allowed it to grow and adapt over two decades and some of the ways in which it has influenced water quality management decisions for this important ecosystem.

Trinh, M. 2024. 2021 Update to Copper Rolling Average. SFEI Contribution No. 1164. San Francisco Estuary Institute: Richmond, CA.
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Trinh, M. 2024. 2021 Update to Cyanide Rolling Averages. San Francisco Estuary Institute: Richmond, CA.
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Thorne, K. M.; Bristow, M. L. 2023. Sediment Deposition and Accretion Data from a Tidal Salt Marsh in South San Francisco Bay, California 2021-2022. U.S. Geological Survey Western Ecological Research Center .

The U.S. Geological Survey, Western Ecological Research Center collected sediment and accretion data at a wave-exposed tidal salt marsh in South San Francisco Bay, California. Sediment traps and feldspar marker horizons (MH) were deployed along transects of increasing distance from the sediment source, at primary, secondary and tertiary marsh channels/bay. Data were collected bi-monthly over two month periods in summer 2021 and winter 2021/2022. Included here are trap and MH plot locations, calculated sediment fluxes at each station by deployment period, annual accretion rates, and covariates associated with sediment deposition and accretion including vegetation structure and elevation. This project aimed to assess the temporal and spatial patterns in sediment deposition in order to better understand sediment delivery and marsh resilience to sea-level rise.

Thompson, B.; Chapman, J. 1997. General guidelines for using the sediment quality triad. Mar. Poll. Bull 34, 368-372 . SFEI Contribution No. 198.
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Thompson, B.; Lowe, S. 2008. Sediment Quality Assessments in the San Francisco Estuary. SFEI Contribution No. 574. San Francisco Estuary Institute: Oakland, Ca.
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Thompson, B.; Daum, T. 1999. Atlas of Sediment Contamination, Toxicity, and Benthic Assemblages in San Francisco Bay. SFEI Contribution No. 38. San Francisco Estuary Institute: Richmond, CA.
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Thompson, B. 1994. Research Recommendations for the San Francisco Estuary: Understanding the Ecosystem. SFEI Contribution No. 181. San Francisco Estuary Institue: Richmond, Ca. p 49.
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Sutton, R. 2016. Microplastic Contamination in San Francisco Bay - Fact Sheet. 2015, Revised 2016. SFEI Contribution No. 770.
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Sutton, R.; Sedlak, M. 2017. Microplastic Monitoring and Science Strategy for San Francisco Bay. SFEI Contribution No. 798. San Francisco Estuary Institute: Richmond, Calif.
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Sutton, R.; Sedlak, M.; Davis, J. A. 2014. Polybrominated Diphenyl Ethers (PBDEs) in San Francisco Bay: A Summary of Occurrence and Trends. SFEI Contribution No. 713. San Francisco Estuary Institute: Richmond, CA. p 62.
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Sutton, R.; Lin, D. 2022. CECs in California’s Ambient Aquatic Ecosystems: Occurrence and Risk Screening of Key Classes. Miller, E., Wong, A., Mendez, M., Eds.. ASC Contribution. SFEI Contribution No. 1066. Aquatic Science Center: Richmond, CA.
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Sutton, R.; Sedlak, M. 2015. Contaminants of Emerging Concern in San Francisco Bay: A Strategy for Future Investigations. 2015 Update. Contaminants of Emerging Concern in San Francisco Bay: A Strategy for Future Investigations. SFEI Contribution No. 761. San Francisco Estuary Institute: Richmond, CA.

About this Update

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) has been investigating contaminants of emerging concern (CECs) since 2001. CECs can be broadly defined as synthetic or naturally occurring chemicals that are not regulated or commonly monitored in the environment but have the potential to enter the environment and cause adverse ecological or human health impacts.

The RMP Emerging Contaminants Workgroup (ECWG), established in 2006, includes representatives from RMP stakeholder groups, regional scientists, and an advisory panel of expert researchers that work together to address the workgroup’s guiding management question – Which CECs have the potential to adversely impact beneficial uses in San Francisco Bay? The overarching goal of the ECWG is to develop cost-effective strategies to identify and monitor CECs to minimize impacts to the Bay.

To this end, the RMP published a CEC Strategy document in 2013 (Sutton et al. 2013). The strategy is a living document that guides RMP special studies on CECs, assuring continued focus on the issues of highest priority to the health of the Bay. A key focus of the strategy is a tiered risk and management action framework that guides future monitoring proposals. The strategy also features a multi-year plan indicating potential future research priorities.

This 2015 CEC strategy update features revised designations of CECs in the tiered risk and management action framework based on monitoring and research conducted since 2013. Brief summaries of relevant RMP findings are provided. In addition, a proposed multi-year plan for future RMP Special Studies on CECs is outlined. A full revision of the CEC strategy is anticipated in 2016. 

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Sutton, R.; Chen, D.; Sun, J.; Greig, D. J.; Wu, Y. 2019. Characterization of brominated, chlorinated, and phosphate flame retardants in San Francisco Bay, an urban estuary. Science of the Total Environment 652, 212-223 . SFEI Contribution No. 859.

Flame retardant chemical additives are incorporated into consumer goods to meet flammability standards, and many have been detected in environmental matrices. A uniquely wide-ranging characterization of flame retardants was conducted, including polybrominated diphenyl ethers (PBDEs) and 52 additional brominated, chlorinated, or phosphate analytes, in water, sediment, bivalves, and harbor seal blubber of San Francisco Bay, a highly urbanized estuary once considered a hot spot for PBDE contamination. Among brominated flame retardants, PBDEs remained the dominant contaminants in all matrices, though declines have been observed over the last decade following their phase-out. Hexabromocyclododecane (HBCD) and other hydrophobic, brominated flame retardants were commonly detected at lower levels than PBDEs in sediment and tissue matrices. Dechlorane Plus (DP) and related chlorinated compounds were also detected at lower levels or not at all across all matrices. In contrast, phosphate flame retardants were widely detected in Bay water samples, with highest median concentrations in the order TCPP > TPhP > TBEP > TDCPP > TCEP. Concentrations in Bay water were often higher than in other estuarine and marine environments. Phosphate flame retardants were also widely detected in sediment, in the order TEHP > TCrP > TPhP > TDCPP > TBEP. Several were present in bivalves, with levels of TDCPP comparable to PBDEs. Only four phosphate flame retardants were detected in harbor seal blubber: TCPP, TDCPP, TCEP, and TPhP. Periodic, multi-matrix screening is recommended to track contaminant trends impacted by changes to flammability standards and manufacturing practices, with a particular focus on contaminants like TDCPP and TPhP that were found at levels comparable to thresholds for aquatic toxicity.

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Sutton, R.; Kucklick, J. 2015. A Broad Scan of Bay Contaminants. San Francisco Estuary Institute: Richmond, CA.
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Sutton, R.; Xie, Y.; Moran, K. D.; Teerlink, J. 2019. Occurrence and Sources of Pesticides to Urban Wastewater and the Environment. In Pesticides in Surface Water: Monitoring, Modeling, Risk Assessment, and Management. Pesticides in Surface Water: Monitoring, Modeling, Risk Assessment, and Management. American Chemical Society: Washington, DC. pp 63-88.

Municipal wastewater has not been extensively examined as a pathway by which pesticides contaminate surface water, particularly relative to the well-recognized pathways of agricultural and urban runoff. A state-of-the-science review of the occurrence and fate of current-use pesticides in wastewater, both before and after treatment, indicates this pathway is significant and should not be overlooked. A comprehensive conceptual model is presented to establish all relevant pesticide-use patterns with the potential for both direct and indirect down-the-drain transport. Review of available studies from the United States indicates 42 pesticides in current use. While pesticides and pesticide degradates have been identified in wastewater, many more have never been examined in this matrix. Conventional wastewater treatment technologies are generally ineffective at removing pesticides from wastewater, with high removal efficiency only observed in the case of highly hydrophobic compounds, such as pyrethroids. Aquatic life reference values can be exceeded in undiluted effluents. For example, seven compounds, including three pyrethroids, carbaryl, fipronil and its sulfone degradate, and imidacloprid, were detected in treated wastewater effluent at levels exceeding U.S. Environmental Protection Agency (US EPA) aquatic life benchmarks for chronic exposure to invertebrates. Pesticides passing through wastewater treatment plants (WWTPs) merit prioritization for additional study to identify sources and appropriate pollution-prevention strategies. Two case studies, diazinon and chlorpyrifos in household pesticide products, and fipronil and imidacloprid in pet flea control products, highlight the importance of identifying neglected sources of environmental contamination via the wastewater pathway. Additional monitoring and modeling studies are needed to inform source control and prevention of undesirable alternative solutions.

Sutton, R.; Lin, D.; Sedlak, M.; Box, C.; Gilbreath, A.; Holleman, R.; Miller, L.; Wong, A.; Munno, K.; Zhu, X.; et al. 2019. Understanding Microplastic Levels, Pathways, and Transport in the San Francisco Bay Region. SFEI Contribution No. 950. San Francisco Estuary Institute: Richmond, CA.

Microplastics (particles less than 5 mm) are ubiquitous and persistent pollutants in the ocean and a pervasive and preventable threat to the health of marine ecosystems. Microplastics come in a wide variety of shapes, sizes, and plastic types, each with unique physical and chemical properties and toxicological impacts. Understanding the magnitude of the microplastics problem and determining the highest priorities for mitigation require accurate measures of microplastic occurrence in the environment and identification of likely sources.

To develop critical baseline data and inform solutions, the San Francisco Estuary Institute and the 5 Gyres Institute have completed the first comprehensive regional study of microplastic pollution in a major estuary. This project supported multiple scientific components to develop improved knowledge about and characterization of microparticles and microplastics in San Francisco Bay and adjacent National Marine Sanctuaries, with the following objectives:

  1. Contribute to the development and standardization of sample collection and analysis methodology for microplastic transportation research.
  2. Determine a baseline for future monitoring of microplastics in San Francisco Bay surface water, sediment, and fish, and in ocean waters outside the Golden Gate.
  3. Characterize pathways by which microplastics enter the Bay, including urban stormwater and treated wastewater effluent.
  4. Investigate the contribution of Bay microplastics to the adjacent National Marine Sanctuaries through computer simulations.
  5. Communicate findings to regional stakeholders and the general public through meetings and educational materials.
  6. Facilitate evaluation of policy options for San Francisco Bay, with recommendations on source reduction.

This document presents the findings of this three-year project. A companion document, “San Francisco Bay Microplastics Project: Science-Supported Solutions and Policy Recommendations,” has been developed by 5 Gyres using the findings of this study (Box and Cummins, 2019).

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Sutton, R.; Mason, S. A.; Stanek, S. K.; Willis-Norton, E.; Wren, I. F.; Box, C. 2016. Microplastic contamination in the San Francisco Bay, California, USA. Marine Pollution Bulletin 109 . SFEI Contribution No. 769.

Despite widespread detection of microplastic pollution in marine environments, data describing microplastic abundance in urban estuaries and microplastic discharge via treated municipal wastewater are limited. This study presents information on abundance, distribution, and composition of microplastic at nine sites in San Francisco Bay, California, USA. Also presented are characterizations of microplastic in final effluent from eight wastewater treatment plants, employing varying treatment technologies, that discharge to the Bay. With an average microplastic abundance of 700,000 particles/km2, Bay surface water appears to have higher microplastic levels than other urban waterbodies sampled in North America. Moreover, treated wastewater from facilities that discharge into the Bay contains considerable microplastic contamination. Facilities employing tertiary filtration did not show lower levels of contamination than those using secondary treatment. As textile-derived fibers were more abundant in wastewater, higher levels of fragments in surface water suggest additional pathways of microplastic pollution, such as stormwater runoff.

Sun, J.; Sutton, R.; Ferguson, L.; Overdahl, K. 2020. New San Francisco Bay Contaminants Emerge. SFEI Contribution No. 931. San Francisco Estuary Institute: Richmond, CA.

In 2016, the RMP launched a novel investigation to detect new or unexpected contaminants in Bay waters, as well as treated sewage (or wastewater) discharged to the Bay. This study used non-targeted analysis, a powerful tool that provides a broad, open-ended view of thousands of synthetic and naturally-derived chemicals simultaneously. We identified hundreds of contaminants, and the results have opened our eyes to urban stormwater runoff as an important pathway for emerging contaminants to enter the Bay.

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Sun, J. 2018. Non-Targeted Analysis of Water-Soluble Compounds Highlights Overlooked Contaminants and Pathways (Coming Soon). SFEI Contribution No. 905. San Francisco Estuary Institute: Richmond, CA.
Sun, J.; Pearce, S.; Trowbridge, P. 2017. RMP Field Sampling Report 2016. SFEI Contribution No. 826. San Francisco Estuary Institute: Richmond, CA.
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Sun, J.; Davis, J.; Stewart, R. 2018. Selenium in Muscle Plugs of White Sturgeon from North San Francisco Bay, 2015-2017. SFEI Contribution No. 929. San Francisco Estuary Institute : Richmond, CA.
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Sun, J.; Davis, J. A.; Stewart, R.; Palace, V. 2019. Selenium in White Sturgeon from North San Francisco Bay: The 2015-2017 Sturgeon Derby Study. SFEI Contribution No. 897. San Francisco Estuary Institute: Richmond, CA.

This report presents the findings from a study evaluating selenium concentrations in white sturgeon (Acipenser transmontanus) tissues collected during the 2015-2017 Sturgeon Derby events in North San Francisco Bay. The goal of this study was to investigate the distribution of selenium among sturgeon tissues to inform the toxicological and regulatory interpretation of selenium measured in non-lethally collected tissues, including muscle plugs and fin rays. This technical report provides documentation of the study and presents its major findings.

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Stevens, D. 2002. Estimation of Means, Totals, and Distribution Functions from Probability Survey Data. SFEI Contribution No. 110. San Francisco Estuary Institute: Oakland, CA.
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Stein, E. D.; Cayce, K.; Salomon, M. N.; Bram, D. L.; De Mello, D.; Grossinger, R. M.; Dark, S. 2014. Wetlands of the Southern California Coast: Historical Extent and Change Over Time. SFEI Contribution No. 720. Southern California Coastal watershed Research Project (SCCWRP), San Francisco Estuary Institute (SFEI), CSU Northridge Center for Geographical Studies: Costa Mesa, Richmond, Northridge.
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