Impact of Stormwater Discharges on Water Quality in Coastal Marine Protected Areas

Marine protected areas worldwide limit harvest to protect sensitive fisheries, but rarely do they address water quality goals that may have equally demonstrable impacts. California has over 500 coastal shoreline miles of marine protected areas designated as Areas of Special Biological Significance (ASBS), but receives untreated wet weather runoff discharges from over 1600 storm drain outfalls. The goal of this study was to assess the extent and magnitude of water quality impacts in ASBS following storm events. A stratified probabilistic design was used for sampling receiving water shorelines near (discharge) and far (non-discharge) from storm drain outfalls. In general, reasonably good water quality exists in California's ASBS following storm events. Many of the target analytes measured did not exceed water quality standards. The post-storm concentrations of most constituents in discharge and non-discharge strata of ASBS were similar. The three potentially problematic parameters identified were total PAH, chromium, and copper.

The Mussel Watch California pilot study on contaminants of emerging concern (CECs): synthesis and next steps

A multiagency pilot study on mussels (Mytilus spp.) collected at 68 stations in California revealed that 98% of targeted contaminants of emerging concern (CECs) were infrequently detectable at concentrations ≤ 1 ng/g. Selected chemicals found in commercial and consumer products were more frequently detected at mean concentrations up to 470 ng/g dry wt. The number of CECs detected and their concentrations were greatest for stations categorized as urban or influenced by storm water discharge. Exposure to a broader suite of CECs was also characterized by passive sampling devices (PSDs), with estimated water concentrations of hydrophobic compounds correlated with Mytilus concentrations. The results underscore the need for focused CEC monitoring in coastal ecosystems and suggest that PSDs are complementary to bivalves in assessing water quality. Moreover, the partnership established among participating agencies led to increased spatial coverage, an expanded list of analytes and a more efficient use of available resources.

Mussel Watch update: long-term trends in selected contaminants from coastal California, 1977-2010

This study examined trends in contaminants measured during three decades of "Mussel Watch" monitoring on the California coast. Chlorinated organic contaminants and butyltins declined the most rapidly, with tissue concentrations in 2010 that were up to 75% lower than during the 1980s. Silver and lead declined at about half of the stations statewide, but generally exhibited slower rates of decline relative to the organic compounds. In contrast, copper increased at many stations, and PAHs showed little evidence for declines. Mussels from San Francisco Bay and the Southern California Bight were historically the most contaminated and have had the steepest declines. Overall, these data show that the "Mussel Watch" approach to monitoring contaminants in California has provided some of the best evidence of the effectiveness of actions to improve water quality over the past 30 years. These datasets also highlight challenges that remain in managing PAHs and copper.

Refocusing Mussel Watch on contaminants of emerging concern (CECs): the California pilot study (2009-10)

To expand the utility of the Mussel Watch Program, local, regional and state agencies in California partnered with NOAA to design a pilot study that targeted contaminants of emerging concern (CECs). Native mussels (Mytilus spp.) from 68 stations, stratified by land use and discharge scenario, were collected in 2009-10 and analyzed for 167 individual pharmaceuticals, industrial and commercial chemicals and current use pesticides. Passive sampling devices (PSDs) and caged Mytilus were co-deployed to expand the list of CECs, and to assess the ability of PSDs to mimic bioaccumulation by Mytilus. A performance-based quality assurance/quality control (QA/QC) approach was developed to ensure a high degree of data quality, consistency and comparability. Data management and analysis were streamlined and standardized using automated software tools. This pioneering study will help shape future monitoring efforts in California's coastal ecosystems, while serving as a model for monitoring CECs within the region and across the nation.

Assessing water quality in Marine Protected Areas from Southern California, USA

Despite the regulatory mandate to maintain "natural water quality", there are ≥ 271 storm drain discharges that potentially threaten the 14 designated marine water quality protected areas in Southern California called Areas of Special Biological Significance (ASBS). After sampling 35 site-events, the geomean concentrations of total suspended solids, nutrients, total and dissolved trace metals, and polycyclic aromatic hydrocarbons in the ocean following storm events were similar between reference drainages and ASBS discharge sites. Concentrations of chlorinated hydrocarbons were nondetectable and no post-storm sample exhibited significant toxicity to the endemic purple sea urchin (Strongylocentrotus purpuratus) near ASBS discharge sites. A reference-based threshold was developed and, despite the similarities in average concentrations, there were some individual ASBS discharge sites that were greater than reference background. Cumulatively across all ASBS, the constituents that were most frequently greater than the reference-based threshold were nutrients and general constituents, followed by dissolved and total trace metals.

Composition and distribution of beach debris in Orange County, California

Many studies have quantified debris collected on beaches around the world. Only a few of those studies have been conducted in the United States, and they are largely limited to semi-quantitative efforts performed as part of volunteer clean-up activities. This study quantifies the distribution and composition of beach debris by sampling 43 stratified random sites on the Orange County, California coast, from August to September 1998. We estimated that approximately 106 million items, weighing 12 metric tons, occur on Orange County beaches. The most abundant items were pre-production plastic pellets, foamed plastics, and hard plastics. Debris density on the remote rocky shoreline was greater than that on high-use sandy beaches for most debris items. This finding partially reflects the periodic clean-up of high-use beaches by local municipalities, and also indicates that a high percentage of the observed debris was transported to the site from waterborne sources.

Population, income, and ecological correlates of child pedestrian injury

Pedestrian injury is a significant health problem among urban children. This study is an analysis of the role of population, income, and ecological factors in the occurrence of child pedestrian collisions. One hundred and ninety-eight motor vehicle collisions occurring in Hartford, Connecticut involving pedestrians younger than 15 years old were reported to police during 1986 through 1987. Collision locations were abstracted from police reports and assigned a census tract. Census tracts were classified as "high frequency" (8+ collisions), "moderate frequency" (3 to 7 collisions), or "low frequency" (0 to 2 collisions). High-frequency census tracts had greater proportions of children and of nonwhite residents than moderate- or low-frequency tracts. They also were characterized by high proportions of households headed by females living below the poverty line. High-frequency tracts had a greater number of children per acre than moderate or low tracts. Children per acre had the strongest association with collision frequency (R = .72) and remained the most consistent when other variables were controlled. The number of children per acre is a potentially useful predictor of census tracts at risk for child pedestrian collisions. This may be useful in developing focused prevention strategies within an urban environment.