SCCWRP News Internal news announcements from the Southern California Coastal Water Research Project Microbes in sewer pipes to be studied to glean insights about origins of fecal contamination <div>SCCWRP and its partners have launched a study investigating whether the microbial community that grows inside sanitary sewer pipes could provide insights into the origins of human fecal contamination found in aquatic environments across Southern California.</div> <div><br /> </div> <div>The study, launched in January, will examine whether the microbial community growing on the inner surfaces of the City of San Diego’s public sewer pipes is unique to this type of infrastructure, a finding that could help researchers discern whether leaking sewer pipes are responsible for human fecal contamination in urban waterways in the San Diego area.</div> <div><br /> </div> <div>Researchers at the University of Wisconsin, Milwaukee, found that a unique microbial community – commonly referred to as biofilm – lives inside Milwaukee’s sewer collection pipes, making it possible for researchers to trace human fecal contamination found in the region’s waterways back to sewer pipes.</div> <div><br /> </div> <div>For the San Diego study, researchers will seek to replicate Milwaukee’s approach to microbial source tracking. Working in collaboration with University of Wisconsin researchers, SCCWRP will use DNA sequencing methods to determine whether the composition of bacteria in San Diego biofilm samples is unique to the City’s sewer pipes, and whether it’s the same across various sampling sites.</div> <div><br /> </div> <div> <div>The study is motivated by a long-term goal among the region’s water-quality managers to understand whether the human fecal signals that are widely detected in San Diego-area flood control infrastructure are coming from leaky public sewer systems, from defects in privately maintained sewer lateral lines and septic systems, or from humans depositing raw fecal material directly into waterways.</div> <div><br /> </div> <div>The biofilm community that lines the insides of sewer pipes is theorized to be the product of unique environmental factors, including temperature, moisture, darkness and a rich nutrient supply.</div> <div>Because biofilm grows in thin layers on the inner surface of sewer pipes, these layers are constantly sloughed off as wastewater flows through the pipes, making the microbes ubiquitous in untreated sewage.</div> <div><br /> </div> <div>During the study, researchers also will examine whether the biofilm signal is strong enough to be reliably detected even when diluted. Biofilm would only be an effective microbial source tracking tool if its signal can be detected above levels of background interference in highly diluted water samples.</div> <div><br /> </div> <div>If the biofilm tracking method continues to show promise, researchers also will examine whether there are any differences in this biofilm community under wet vs. dry weather conditions.</div> <div>Sampling in San Diego will continue through May, with results expected as early as this summer.</div> <div><br /> </div> <div>For more information, contact Dr. <a href="">John Griffith</a>.</div> <div><br /> </div> <div><img alt="" src="/Images/News/StormDrainChannels.jpg" style="width: 450px; height: 300px; border-width: 1px; border-style: solid;" /><br /> </div> <div><span style="font-family: arial; font-size: 12px;">Human fecal contamination has been detected in storm drain channels across the San </span></div> <div><span style="font-family: arial; font-size: 12px;">Diego area that drain to coastal waters, including Tourmaline Surfing Park, above.</span></div> <div><span style="font-family: arial; font-size: 12px;">Researchers have launched a study that could provide insights into whether leaking </span></div> <div><span style="font-family: arial; font-size: 12px;">public sewer pipes could be responsible for the contamination.</span></div> </div> commassistant ad575d42-96de-4a7a-9f1c-c21ff06197fe Fri, 09 Feb 2018 01:42:59 GMT Study launched to revisit copper TMDL for Marina del Rey Harbor <div>SCCWRP has launched a two-year study examining whether existing regulatory targets for dissolved copper in Marina del Rey Harbor should be modified to more accurately reflect the ecological threat posed by copper.</div> <div><br /> </div> <div>The study, which kicked off in January, will document the concentrations of copper that aquatic organisms in the Los Angeles County boat harbor are exposed to at different times of the year, and how toxic these copper levels are at different sites across the harbor. </div> <div><br /> </div> <div>Under the harbor’s existing Total Maximum Daily Load (TMDL) regulatory target, Marina del Rey Harbor is required to reduce copper loading by 85%, which would require boat owners to make significant changes to the types of anti-fouling paint they typically use on the underside of boats.</div> <div><br /> </div> <div>Although copper in boat paint plays an essential role in preventing barnacles and other marine life from attaching and growing on the underside of boats, water quality in the boat harbor frequently exceeds the regulatory standard of 3.1 ug/L for copper. Marina del Rey is the largest man-made, small-boat harbor in California.</div> <div><br /> </div> <div> <div>The regulatory target for copper was originally set based on the results of standardized laboratory toxicity tests. However, because the tests used purified seawater, researchers don’t know if dissolved copper in Marina del Rey is as toxic to aquatic life as it would be in purified seawater. Previous research has indicated that factors such as dissolved organic carbon can influence the bioavailability of dissolved copper to aquatic life.</div> <div><br /> </div> <div>The SCCWRP study will seek to use an approach endorsed by the U.S. Environmental Protection Agency to set a site-specific water-quality objective for dissolved copper. The approach enables water-quality managers to consider the effect of local water-quality characteristics on copper toxicity. </div> <div><br /> </div> <div>The site-specific objectives approach has been used to modify copper regulatory targets for San Francisco Bay, the Los Angeles River and Calleguas Creek in Ventura County.</div> </div> <div><br /> </div> <div>Also during the study, researchers will test-drive a recently developed marine version of the Biotic Ligand Model (BLM) to predict variations in Marina del Rey Harbor copper toxicity based on water-quality characteristics. A proposed revision of the EPA water-quality criteria for copper uses the BLM; this study will provide information on how well the model performs in Southern California waters.</div> <div><br /> </div> <div> <div>Sampling for the study, which began in January, is expected to continue through 2019. A draft work plan for the study will be distributed for public review in the coming months. </div> <div><br /> </div> <div>For more information, contact <a href="">Steven Bay</a><br /> <br /> <img alt="" src="/Images/News/CopperBasedPaints.jpg" style="width: 450px; height: 314px; border-width: 1px; border-style: solid;" /> </div> <div><span style="font-family: arial; font-size: 12px;">Barnacles, algae and other marine life attach to the underside of a boat that has been</span></div> <div><span style="font-family: arial; font-size: 12px;"> raised out of the water. Copper-based paints play a key role in preventing this fouling, </span></div> <div><span style="font-family: arial; font-size: 12px;">but because the copper dissolves in water, the water-quality regulatory targets for</span><span style="font-family: arial; font-size: 12px;"> copper </span></div> <div><span style="font-family: arial; font-size: 12px;">in places like Marina del Rey Harbor have been exceeded. SCCWRP and its partners </span></div> <div><span style="font-family: arial; font-size: 12px;">are pursuing a study examining whether the regulatory target for copper should be</span></div> <div><span style="font-family: arial; font-size: 12px;"> modified to more accurately reflect its ecological threat.</span></div> </div> commassistant 54589561-540e-4b76-a6d0-ec34838696e0 Fri, 09 Feb 2018 01:32:38 GMT Technical foundation created for ephemeral stream tools <p>SCCWRP and its partners have completed a pair of studies that establish a technical foundation for building watershed management tools for Southern California streams that run dry for much of the year.</p> <p>The two studies, published as SCCWRP technical reports in December, provide an important proof-of-concept of the feasibility of building tools that can quantitatively<a href=""> assess the health of ephemeral streams</a>, as well as that can <a href="">model the hydrologic flow patterns of ephemeral streams</a>.</p> <p>Although ephemeral streams make up about 60% of all streams in Southern California, existing watershed management tools are designed for application in perennial streams only.</p> <p>The two studies, which were conducted in the Santa Ana and San Diego regions, represent an important step forward in building a suite of ephemeral stream management tools that complement existing perennial stream tools.&nbsp;</p> <p>During the ephemeral streams condition assessment study, researchers examined the composition of terrestrial arthropod and bryophyte communities living in dry streambeds. Multiple biological indicators were identified that could potentially be used to quantitatively score the condition of these ephemeral streams.&nbsp;</p> <p>Based on these findings, SCCWRP and its partners are continuing to work toward developing the quantitative scoring tool for ephemeral stream condition; it is expected to be released in 2020.</p> <p>Furthermore, the ephemeral streams bioindicator data collected during the study is being used to validate the California Rapid Assessment Method (CRAM) tool for ephemeral streams, which was co-developed by SCCWRP. By validating this screening-level ephemeral streams assessment tool, California’s stream managers will have more confidence in the accuracy of the tool, encouraging more widespread adoption among California’s stream monitoring programs.</p> <p>During the ephemeral streams hydrologic mapping project, researchers adapted hydrologic models developed by the U.S. Geological Survey to predict typical monthly flows for ephemeral streams under wet, normal, and dry climatic conditions. Researchers then modeled theimpacts that human disturbances have on these flow patterns over time.&nbsp;</p> <p>The resulting hydrologic maps – available as shapefiles and through an <a href="">interactive web application</a> – reveal the extent and location of ephemeral streams, as well as capture the dynamic nature of ephemeral stream flows across Southern California over time.</p> <p>The hydrologic maps have the potential to support a variety of management needs, including prioritizing sites for monitoring, providing evidence for causal assessment studies, forecasting the impacts of land-use changes and climate change, and informing the design of stream bioassessment surveys.</p> <p>SCCWRP’s work on ephemeral streams has opened the door to partnerships that will expand this science outside of California. Notably, SCCWRP is partnering with the U.S. Environmental Protection Agency and the Arizona Department of Environmental Quality to evaluate the new ephemeral streams tools for Arizona as well.&nbsp;</p> <p>SCCWRP also is partnering with the EPA to evaluate field-based flow duration assessment tools across the arid Southwest that were originally developed for the Pacific Northwest.</p> <p>&nbsp;For more information, contact Dr. <a href="">Raphael Mazor</a>.</p> <p>&nbsp;<img alt="" src="/Images/News/HydrologicMap.JPG" style="width: 450px; height: 417px; border-width: 1px; border-style: solid;" /></p> <span style="font-family: arial; font-size: 12px;">SCCWRP and its partners have developed a series of hydrologic maps that estimate <br /> the historic flows of ephemeral streams. The maps above show flow conditions in the <br /> Santa Ana region in January, left, and July, right, under three different types of seasonal <br /> rainfall patterns (dry, normal, and wet). From these interactive, customizable maps, <br /> watershed managers can understand the dynamic nature of ephemeral stream flows<br /> over time.</span> commassistant 0b25a8dc-0dab-4da4-b441-43c7afc87b6a Fri, 09 Feb 2018 01:07:34 GMT Draft framework unveiled for assessing human health impacts of contaminated sediment SCCWRP and its partners have completed development of a standardized sediment assessment framework intended to better protect the health of humans who consume seafood caught in enclosed bays and estuaries in California. <div><br /> </div> <div>The draft framework, published as a<a href=""> SCCWRP technical report</a> in October, is being considered for adoption by the State Water Board to define for environmental managers how to implement California’s Sediment Quality Objective (SQO) for protection of human health. </div> <div><br /> </div> <div>The human health SQO – one of three adopted by the State Water Board in 2008 for enclosed bays and estuaries – is a one-sentence regulatory target that calls on sediment contamination to not be present “at levels that will bioaccumulate in aquatic life to levels that are harmful to human health.” </div> <div><br /> </div> <div>SCCWRP and its partners have spent more than a decade conceptualizing, building and vetting the human health SQO framework to create a standardized technical definition of what it means to be in compliance with this regulatory target. </div> <div><br /> </div> <div>California’s environmental management community will be able to use the framework to inform decision-making on issues like setting appropriate sediment clean-up targets. </div> <div><br /> </div> <div>The draft framework relies on standardized, quantitative indicators of sediment contamination’s human health effects to score the quality of sediment in enclosed bays and estuaries. Indicator scores are classified into condition categories ranging from “unimpacted” to “clearly impacted.” </div> <div><br /> </div> <div>The human health framework is designed to complement California’s SQO assessment framework for the protection of sediment-dwelling aquatic life, which was adopted by the State Water Board and approved for regulatory use in enclosed bays and estuaries in 2009. Both frameworks use standardized, quantitative indicators with defined thresholds to provide consistency and statewide comparability. </div> <div><br /> </div> <div>There is not yet an approved assessment framework in place to support California’s third SQO, which applies to the protection of fish and wildlife. Under the human health SQO framework, sediment sampling sites are assessed in two main ways:</div> <div><br /> </div> <div> <ul> <li><strong> Chemical exposure analysis:</strong> Sportfish tissue chemistry data are compared to the advisory sportfish tissue contamination levels developed by California’s Office of Environmental Health Hazard Assessment (OEHHA).</li> <li><strong>Site linkage analysis</strong>: The linkage between site sediment contamination and tissue contaminant concentration is evaluated. </li> </ul> <div>The framework features a three-tiered assessment process that provides capability to adapt the assessment to a wide range of situations. The framework also makes use of a food web bioaccumulation model to evaluate site linkage.</div> <div><br /> </div> <div> Assessments using the framework will be focused around PCBs (polychlorinated biphenyls) and chlorinated pesticides – two major chemical drivers of seafood consumption risk. </div> <div><br /> </div> <div>SCCWRP and its partners began conceptualizing pieces of the draft framework in 2005, and started developing the technical aspects in 2009 with the guidance of a scientific steering committee as the project came into sharper focus. A stakeholder advisory committee that included participation by SCCWRP member agencies also played a key role in shaping the framework.</div> <div><br /> </div> <div> Final refinements to the framework, which were completed over the past year, included harmonizing tissue chemistry evaluation thresholds with OEHHA’s seafood consumption advisory tissue levels, completing a four-year test drive of the framework in the greater Los Angeles Harbors area, and refining the bioaccumulation model used to evaluate sediment contamination. </div> <div><br /> </div> <div>The State Water Board will solicit public comments on the draft framework through the end of 2017, and hold an informational public workshop on December 5, 2017 in Sacramento. The draft framework is scheduled to be considered for adoption by the State Water Board in March 2018. </div> <div><br /> </div> <div>For more information, contact<a href=""> Steve Bay</a>.</div> </div> <div><br /> </div> <div><img alt="" src="/Images/News/SQOHumanHealthFramework.jpg" style="width: 450px; height: 655px; border-width: 1px; border-style: solid;" /><br /> </div> <div> <p class="Caption2"></p> <span style="font-size: 12px; font-family: arial;">SCCWRP and its partners have developed a sediment quality framework that establishes</span></div> <div><span style="font-size: 12px; font-family: arial;"> a standardized technical definition of what it means to be in compliance with California’s</span></div> <div><span style="font-size: 12px; font-family: arial;"> Sediment Quality Objective (SQO) for the protection of human health in enclosed bays</span></div> <div><span style="font-size: 12px; font-family: arial;"> and estuaries. The draft framework was published as a SCCWRP technical report, above.</span> <p class="Caption2"></p> <p class="Caption2"><o:p></o:p></p> </div> commassistant 5edd5f18-9ab6-4e26-b8e2-03136a5c5aa5 Mon, 20 Nov 2017 18:33:50 GMT