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Stormwater agencies in the San Francisco Bay Area are identifying watershed areas that are polluted with PCBs in order to prioritize management efforts to reduce impairment in the Bay caused by PCBs carried in stormwater. Water sampling during storms has been used to characterize PCB concentrations but management prioritization based on the comparison of concentrations between watersheds is made difficult due to variations in flow and sediment erosion between storms and in relation to varying land use. In addition, identifying PCB source areas within priority watersheds has proven complex and costly. To address these challenges, the San Francisco Bay Regional Monitoring Program (RMP) has developed two new interpretive methods based on storm-event PCB yields (PCBs mass per unit area per unit time) and fingerprints of Aroclors (commercial PCB mixtures) that make existing data more useful for decision-making. 

The objectives of this study were to: 

• Apply the yield method to the regional stormwater dataset and provide new rankings, 
• Estimate the presence of Aroclors in samples where congener data are available
• Evaluate data weaknesses and recommend watersheds to resample, and
• Classify watersheds into high, medium, and low categories for potential management.

The response of shallow groundwater to sea-level rise is a relatively new field of study. For low-lying coastal communities, sea-level rise adaptation efforts must consider the potential for groundwater rise to avoid maladaptation. The need to better understand this slow and chronic threat was identified as a critical data gap in the San Francisco Bay Area’s (Bay Area’s) adaptation efforts during the Bay Area Groundwater and Sea-Level Rise Workshop in 2019.

Pathways Climate Institute LLC (Pathways) and the San Francisco Estuary Institute (SFEI) gathered and analyzed multiple data sets and collaborated with city and county partners to analyze and map the existing “highest annual” shallow groundwater table and its likely response to future sea-level rise. This effort covers four counties (Alameda, Marin, San Francisco, San Mateo) and was funded by the Bay Area Council’s California Resilience Challenge. The study focused on the San Francisco Bay side of each county and does not include the Pacific coastline of Marin, San Francisco, nor San Mateo Counties. An advisory committee composed of city and county representatives provided essential support by gathering data and reviewing depth-to-groundwater maps. Additional academic and agency advisors participated in project team meetings and informed project direction. This effort produced the following publicly available data and online tools to support adaptation efforts:

• Existing and future condition depth to groundwater GIS data available for download (geodatabase format).
• A StoryMap providing background information and graphical representations of the processes and impacts of groundwater rise.
• Web maps showing: (1) existing depth to groundwater; and (2) a comparison of the extent of emergent groundwater to the extent of coastal flooding under various sea-level-rise scenarios.

Municipal wastewater effluent has been proposed as one pathway for microplastics to enter the aquatic environment. Here we present a broad study of municipal wastewater treatment plant effluent as a pathway for microplastic pollution to enter receiving waters. A total of 90 samples were analyzed from 17 different facilities across the United States. Averaging all facilities and sampling dates, 0.05 ± 0.024 microparticles were found per liter of effluent. Though a small value on a per liter basis, even minor municipal wastewater treatment facilities process millions of liters of wastewater each day, yielding daily discharges that ranged from ∼50,000 up to nearly 15 million particles. Averaging across the 17 facilities tested, our results indicate that wastewater treatment facilities are releasing over 4 million microparticles per facility per day. Fibers and fragments were found to be the most common type of particle within the effluent; however, some fibers may be derived from non-plastic sources. Considerable inter- and intra-facility variation in discharge concentrations, as well as the relative proportions of particle types, was observed. Statistical analysis suggested facilities serving larger populations discharged more particles. Results did not suggest tertiary filtration treatments were an effective means of reducing discharge. Assuming that fragments and pellets found in the effluent arise from the 'microbeads' found in many cosmetics and personal care products, it is estimated that between 3 and 23 billion (with an average of 13 billion) of these microplastic particles are being released into US waterways every day via municipal wastewater. This estimate can be used to evaluate the contribution of microbeads to microplastic pollution relative to other sources (e.g., plastic litter and debris) and pathways (e.g., stormwater) of discharge.

This report describes the updates to the vernal pool habitat map, the development of the ambient baseline ecological condition survey of vernal pool systems within the Central Valley, and the development and results of the habitat development curve. A fictional project example shows how CRAM and the vernal pool complex CDFs and HDCs can help project proponents and the regulatory agencies think critically about project designs (using CRAM Attributes and Metrics as a standard measure), evaluate project conditions within a regional landscape context, and monitor project performance over time to ensure that project goals are met.

Funding for this report was provided through an agreement with the U.S. Environmental Protection Agency (USEPA).  This report does not necessarily reflect the views and policies of USEPA nor does the mention of trade names or commercial products within this report constitute endorsement or recommendation for use.

This 20-year water quality monitoring status and trends report for the Lahontan Water Board’s Surface Water Ambient Monitoring Program (Regional SWAMP) provides an overview of the environmental settings across the Region to give the reader a sense of the diverse ecological landscape, land uses, distribution and abundance of aquatic resources, and fire history. It includes a retrospective analysis of the Regional SWAMP’s ongoing, targeted water quality monitoring results (2000 - 2021), and concludes by presenting an adaptive monitoring and assessment framework (adapted from the California Wetlands Monitoring Workgroup's Wetland and Riparian Monitoring Plan, known as "WRAMP").  The framework was used to review the program and recommend future monitoring changes to improve efficiencies and address some of the recommendations listed in the Regional SWAMP's 2019 Core Program Review. 

This report synthesizes the baseline assessments for Santa Clara County’s five watersheds to present similarities, differences, and compare ecological condition in streams across watersheds and their subregions, San Francisco Bay-Delta ecoregion, and statewide based on CRAM. It also interprets the assessment results and comparisons to identify risks to stream conditions, and opportunities for stream stewardship. Project D5’s baseline assessments establish a monitoring and assessment framework for evaluating the performance of Valley Water’s programs, projects, maintenance activities, and on-the-ground stewardship actions.

This technical report describes the ten-year ambient stream condition reassessment survey design and monitoring plan (or strategy) for the Coyote Creek watershed. Because the reassessment employed (and modified) the 2010 sample draw, essential background information about the original 2010 probability-based survey design, sample draw, and field assessment outcomes were provided.

In 2016 The Santa Clara Valley Water District and its consultants conducted a watershed wide survey to characterize the distribution and abundance of the aquatic resources within the Lower Peninsula watershed wtihin Santa Clara County, CA based on available GIS data, and to assess the overall ecological condition of streams within the watershed based on a statistically based, random sample design and the California Rapid Assessment Method for streams (CRAM).

In 2015 The Santa Clara Valley Water District and it's consultants conducted a watershed wide survey to characterize the distribution and abundance of the aquatic resources within the upper Pajaro River watershed wtihin Santa Clara County, CA based on available GIS datasets, and to assess the overall ecological condition of streams within the watershed based on a statistically based random sample design and the California Rapid Assessment Method for streams (CRAM).

This report describes the application of GreenPlan-IT’s Site Locator Tool to identify and rank candidate GI installation sites within the City of Ukiah.  The Site Locator Tool is the first (foundational) tool of the GreenPlan-IT toolkit, meaning that the outputs are required inputs for both the Hydrologic Modeling and Optimization tools.   The Site Locator Tool addresses the question: where are the best locations for GI implementation based on local planning priorities?