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Filters: Author is Trowbridge, P.  [Clear All Filters]
2018
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.; 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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Shimabuku, I.; Trowbridge, P.; Salop, P. 2018. 2018 RMP Bivalve Deployment Cruise Plan. SFEI Contribution No. 892. San Francisco Estuary Institute: Richmond, CA.
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Franz, A.; Trowbridge, P.; Salop, P. 2018. 2018 RMP Sediment Sampling and Analysis Plan. SFEI Contribution No. 904. San Francisco Estuary Institute: Richmond, CA.
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Jabusch, T.; Trowbridge, P.; Wong, A.; Heberger, M. 2018. Assessment of Nutrient Status and Trends in the Delta in 2001–2016: Effects of drought on ambient concentrations and trends. SFEI Contribution No. 865. Aquatic Science Center: Richmond, CA.

Nutrients and the effects of nutrients on water quality in the Sacramento-San Joaquin Delta is a priority focus area for the Delta Regional Monitoring Program (Delta RMP). The Program’s first assessment question regarding nutrients is: “How do concentrations of nutrients (and nutrient-associated parameters) vary spatially and temporally?” In this analysis, we confirmed previously reported declining trends in the San Joaquin River for nutrient concentrations at Vernalis and chlorophyll-a concentrations at Buckley Cove and Disappointment Slough. A slight increasing trend for dissolved oxygen at Buckley Cove was also detected which could be confirmation that management actions for the San Joaquin River Dissolved Control Program are having the desired effect. Finally, at stations in Suisun Bay, the Confluence region, and Franks Tract, chlorophyll-a showed modest increasing trends, which were not evident in previous analyses. The new analyses presented in this report and the findings from earlier reports constitute encouraging early progress toward answering the Delta RMP’s assessment questions. Specifically, due to the existence of long-term data sets and synthesis efforts, spatial and temporal trends in the concentrations of nutrients and nutrient-related parameters are reasonably well understood and so are the magnitudes of the most important sources of nutrients from outside the Delta. However, additional synthesis work could be done to understand the factors behind these trends. Large knowledge gaps remain about nutrient sinks, sources, and processes within the Delta. The mechanistic, water quality-hydrodynamic models being developed for the Delta may be able to address these questions in the future.

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Shimabuku, I.; Trowbridge, P.; Sun, J. 2018. Bay 2017 Bay RMP Field Sampling Report. SFEI Contribution No. 849. San Francisco Estuary Institute : Richmond, CA.
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Jabusch, T.; Trowbridge, P.; Heberger, M.; Orlando, J.; De Parsia, M.; Stillway, M. 2018. Delta Regional Monitoring Program Annual Monitoring Report for Fiscal Year 2015–16: Pesticides and Toxicity. SFEI Contribution No. 864. Aquatic Science Center: Richmond, CA.

The primary purpose of this report is to document the first year (FY15/16) of pesticide monitoring by the Delta Regional Monitoring Program (Delta RMP). This document reports the results from samples collected monthly from July 2015 through June 2016. The data described in this report are available for download via the California Environmental Data Exchange Network (CEDEN) website.

Pesticide monitoring of the Delta RMP includes chemical analysis and toxicity testing of surface water samples. The parameters analyzed include 154 current use pesticides, dissolved copper, field parameters, and “conventional” parameters (ancillary parameters measured in the laboratory, such as dissolved/particulate organic carbon and hardness). Toxicity tests included an algal species (Selenastrum capricornutum, also known as Raphidocelis subcapitata), an invertebrate (Ceriodaphnia dubia, a daphnid or water flea), and a fish species (Pimephales promelas, fathead minnow). Toxicity testing included the evaluation of acute (survival) and chronic (growth, reproduction, biomass) toxicity endpoints. The surface water samples were collected from 5 fixed sites representing key inflows to the Delta that were visited monthly: Mokelumne River at New Hope Road, Sacramento River at Hood, San Joaquin River at Buckley Cove, San Joaquin River at Vernalis, and Ulatis Creek at Brown Road.

A total of 52 pesticides were detected above method detection limits (MDLs) in water samples (19 fungicides, 17 herbicides, 9 insecticides, 6 degradates, and 1 synergist). A total of 9 pesticides (5 herbicides, 3 insecticides, and 1 degradate) were detected in suspended sediments in 10 of a total of 60 samples collected during the study period. All collected samples contained mixtures of pesticides ranging from 2 to 26 pesticides per sample. From a total of 154 target parameters, 100 compounds were never detected in any of the samples.

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Jabusch, T.; Trowbridge, P.; Heberger, M.; Guerin, M. 2018. Delta Regional Monitoring Program Nutrients Synthesis: Modeling to Assist Identification of Temporal and Spatial Data Gaps for Nutrient Monitoring. SFEI Contribution No. 866. Aquatic Science Center: Richmond, CA.

Nutrient loads are an important water quality management issue in the Sacramento-San Joaquin Delta (Delta) and there is consensus that the current monitoring activities do not collect all the information needed to answer important management questions. The purpose of this report is to use hydrodynamic model outputs to refine recommendations for monitoring nutrients and related conditions in the Delta. Two types of modeling approaches were applied: 1) volumetric water source analysis to evaluate the mix of source waters within each subregion; and 2) particle tracking simulations.The analysis revealed that each Delta subregion has a unique “fingerprint” in terms of how much of its water comes from different sources. Three major recommendations for a future monitoring design were derived from this analysis:

Recommendation #1: The subregions proposed for status and trends monitoring in a previous report should be redrawn to better reflect the mixtures of source waters.

Recommendation #2: Long-term water quality stations are needed in the North Delta, Eastside, and South Delta subregions.

Recommendation #3: Areas with a long-residence time and where mixing of different water sources occurs are potential for nutrient transformation hotspots. High-frequency water quality mapping of these areas has the

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Shimabuku, I.; Pearce, S.; Trowbridge, P.; Franz, A.; Yee, D.; Salop, P. 2018. Field Operations Manual for the Regional Monitoring Program. SFEI Contribution No. 902. San Francisco Estuary Institute: Richmond, CA.
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Wu, J.; Trowbridge, P.; Yee, D.; McKee, L.; Gilbreath, A. 2018. RMP Small Tributaries Loading Strategy: Trends Strategy 2018. SFEI Contribution No. 886. San Francisco Estuary Institute : Richmond, CA.
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Schoellhamer, D.; McKee, L.; Pearce, S.; Kauhanen, P.; Salomon, M.; Dusterhoff, S.; Grenier, L.; Marineau, M.; Trowbridge, P. 2018. Sediment Supply to San Francisco Bay. SFEI Contribution No. 842. 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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2017
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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Lin, D.; Sun, J.; Yee, D.; Franz, A.; Trowbridge, P.; Salop, P. 2017. 2017 RMP Water Cruise Plan. SFEI Contribution No. 845. 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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Yee, D.; Wong, A.; Shimabuku, I.; Trowbridge, P. 2017. Characterization of Sediment Contamination in Central Bay Margin Areas. SFEI Contribution No. 829. 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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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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2016
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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.

Schiff, K.; Trowbridge, P. R.; Sherwood, E. T.; Tango, P.; Batiuk, R. A. 2016. Regional monitoring programs in the United States: Synthesis of four case studies from Pacific, Atlantic, and Gulf Coasts. Regional Studies in Marine Science 4.

Water quality monitoring is a cornerstone of environmental protection and ambient monitoring provides managers with the critical data they need to take informed action. Unlike site-specific monitoring that is at the heart of regulatory permit compliance, regional monitoring can provide an integrated, holistic view of the environment, allowing managers to obtain a more complete picture of natural variability and cumulative impacts, and more effectively prioritize management actions. By reviewing four long-standing regional monitoring programs that cover portions of all three coasts in the United States–Chesapeake Bay, Tampa Bay, Southern California Bight, and San Francisco Bay–important insights can be gleaned about the benefits that regional monitoring provides to managers. These insights include the underlying reasons that make regional monitoring programs successful, the challenges to maintain relevance and viability in the face of ever-changing technology, competing demands and shifting management priorities. The lessons learned can help other managers achieve similar successes as they seek to establish and reinvigorate their own monitoring programs.

Hunt, J.; Trowbridge, P.; Yee, D.; Franz, A.; Davis, J. 2016. Sampling and Analysis Plan for 2016 RMP Status and Trends Bird Egg Monitoring. SFEI Contribution No. 827. San Francisco Estuary Institute: Richmond, CA. p 31 pp.
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Senn, D.; Trowbridge, P. 2016. San Francisco Bay Nutrient Management Strategy Observation Program. SFEI Contribution No. 877. San Francisco Estuary Institute: Richmond, CA.
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2015
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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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