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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? 

Reconnaissance monitoring for water years 2015, 2016, 2017, 2018 and 2019 was completed with funding provided by the Regional Monitoring Program for Water Quality in San Francisco Bay (RMP). This report is designed to be updated each year until completion of the study. At least one additional water year (2020) is underway. An earlier draft of this report was prepared for the Bay Area Stormwater Management Agencies Association (BASMAA) in support of materials submitted on or before March 31st 2020 in compliance with the Municipal Regional Stormwater Permit (MRP) Order No. R2-2015-0049.

The San Francisco Bay polychlorinated biphenyl (PCB) and mercury (Hg) total maximum daily loads (TMDLs) call for implementation of control measures to reduce PCB and Hg loads entering the Bay via stormwater. In 2009, the San Francisco Bay Regional Water Quality Control Board (Regional Water Board) issued the first Municipal Regional Stormwater Permit (MRP). This MRP contained a provision aimed at improving information on stormwater pollutant loads in selected watersheds (Provision C.8.) and piloted a number of management techniques to reduce PCB and Hg loading to the Bay from smaller urbanized tributaries (Provisions C.11. and C.12.). To address C8, a previously developed fixed station loads monitoring technique was refined that incorporated turbidity and stage sensors recording at 5-15 minute intervals with the collection of velocity and water samples using both manual and auto sampling techniques to compute loads. In 2015, the Regional Water Board issued the second iteration of the MRP. “MRP 2.0” placed an increased focus on identifying those watersheds, source areas, and source properties that are potentially the most polluted and are therefore most likely to be cost-effective areas for addressing load-reduction requirements.

Per- and polyfluoroalkyl substances (PFAS), a family of thousands of synthetic, fluorine-rich compounds commonly referred to as “forever chemicals,” are known for their thermal stability, non-reactivity, and surfactant properties. These unique compounds have widespread uses across consumer, commercial, and industrial products, resulting in widespread occurrence in the environment and wildlife across the globe. This study analyzed ambient surface water in San Francisco Bay for 40 PFAS to discern the occurrence, fate, and potential risks to ecological and human health.

Eleven of 40 PFAS were detected in ambient surface water collected in 2021 from 22 sites in the Bay. Seven PFAS (PFPeA, PFHxA, PFHpA, PFOA, PFBS, PFHxS, and PFOS), were found in at least 50% of samples. PFHxA and PFOA were the most frequently detected analytes (detection frequencies of 86% and 77%, respectively). PFPeA and PFHxA were generally found at the highest concentrations across sites, with median and maximum concentrations of 1.6 and 4.8 ng/L and 1.5 and 5.7 ng/L, respectively. Pairwise Spearman's correlations revealed strong positive correlations  (p <0.001; r > 0.77) among the seven PFAS detected in at least 50% of sites, suggesting significant similarities between their sources, pathways, and/or fate in the environment. PFBA, PFNA, PFDA, and 6:2 FTS were found at a limited number of sites in the Bay. 6:2 FTS was found at a single site at 14 ng/L, the highest concentration of any individual PFAS in the Bay. The sums of detected PFAS for all sites had median and maximum concentrations of 10 and 29 ng/L, respectively.

This study reconstructs the historical landscape of the Petaluma River watershed and documents the major landscape changes that have taken place within the watershed over the past two centuries. Prior to Spanish and American settlement of the region, the Petaluma River watershed supported a dynamic and interconnected network of streams, riparian forests, freshwater wetlands, and tidal marshes. These habitats were utilized by a wide range of plant and animal species, including a number of species that are today listed as threatened or endangered such as Ridgway’s Rail, Black Rail, salt marsh harvest mouse, California red-legged frog, Central California Coast steelhead, and soft bird’s beak (CNDDB 2012, SRCD 2015). Agricultural and urban development beginning in the mid-1800s has significantly altered the landscape, degrading habitat for fish and wildlife and contributing to contemporary management challenges such as flooding, pollutant loading, erosion, and sedimentation. While many natural areas and remnant wetlands still exist throughout the watershed—most notably the Petaluma Marsh—their ecological function is in many cases seriously impaired and their long-term fate jeopardized by climate change and other stressors. Multi-benefit wetland restoration strategies, guided by a thorough understanding of landscape history, can simultaneously address a range of chronic management issues while improving the ecological health of the watershed, making it a better place to live for both people and wildlife.

Conceptual models developed for selected San Francisco Bay margin areas (referred to as priority margin units, or PMUs) have identified shiner surfperch as a crucial indicator of PCB impairment, due to their explicit inclusion as an indicator species in the PCBs TMDL, importance as a popular sport fish species, tendency to accumulate high PCB concentrations, site fidelity, and other factors. The conceptual models recommend periodic monitoring of shiner surfperch to track trends in the PMUs, and as the ultimate indicator of progress in reduction of impairment. The objectives of this study were to 1) establish baselines for long-term monitoring of PCB concentrations in shiner surfperch in four PMUs, and 2) understand local spatial variation in shiner PCB concentrations to support optimization of the long-term sampling design. This study also provided valuable information on the presence of shiner surfperch and other species in the PMUs. 

This report was prepared as a briefing document for a September 2016 workshop held in Sacramento by the Delta Regional Monitoring Program. The purpose of the workshop was to plan how to invest in nutrients-related studies in order to inform better management of Delta waterways. First, the report compiles information about the major existing nutrient monitoring programs in the Sacramento-San Joaquin Delta. Next, it outline options for “no regrets” actions for workshop participants to review. The report summarizes interviews with representatives of Delta monitoring and resource management programs, describes current monitoring efforts in the Delta, and presents the conclusions and recommendations from recently completed data syntheses.

This report explores the potential for integrating ecological functions into flood risk management on lower Novato Creek. It presents an initial vision of how ecological elements could contribute to flood protection, based on a broad scale analysis and a one day workshop of local and regional experts. The Vision is not intended to be implemented as is, but rather adapted and applied through future projects and analysis. Other actions (e.g., floodwater detention basins) may also need to be implemented in the interim to meet flood risk objectives.

Project Background

Over the past century and a half, lower Novato Creek and the surrounding tidal wetlands have been heavily modified for flood control and land reclamation purposes. Levees were built in the tidal portion of the mainstem channel beginning in the late 1800s to convey flood flows out to San Pablo Bay more rapidly and to remove surrounding areas from inundation. Following levee construction, the wetlands surrounding the channel were drained and converted to agricultural, residential, and industrial areas. These changes have resulted in a considerable loss of wetland habitat, reduced sediment transport to marshes and the Bay, and an overall decreased resilience of the system to sea level rise.
In addition to tidal wetland modification, land use changes upstream in the Novato Creek watershed have resulted in several challenges for flood control management. Dam construction and increased runoff in the upper watershed have resulted in elevated rates of channel incision, which have increased transport of fine sediment from the upper watershed to lower Novato Creek. Channelization of tributaries and construction of irrigation ditches have likely increased drainage density in the upper watershed, also potentially contributing to increased rates of channel incision and fine sediment production (Collins 1998). Downstream, sediment transport capacity has been reduced by construction of a railroad crossing and loss of tidal prism and channel capacity associated with the diking of the surrounding marsh. As a result of the increased fine sediment supply from the watershed and the loss of sediment transport capacity in lower Novato Creek, sediment aggradation occurs within the channel, which in turn reduces the flood capacity of the channel, necessitating periodic dredging.

Currently, the Marin County Department of Public Works (MCDPW) is coordinating the Novato Watershed Program, which includes Marin County Flood Control and Water Conservation District, Novato Sanitary District, and North Marin Water District. Within lower Novato Creek, the Program is seeking to implement a new approach to flood control that includes redirecting sediment for beneficial use, reducing flood channel maintenance costs, restoring wetland habitat, and enhancing resilience to sea level rise. Included as part of this goal is the re-establishment of historical physical processes that existed before major channel modification, which in turn will re-establish historical ecological functions and help to create a tidal landscape that is resilient to increasing sea level.