This report is one of three technical reports of Tracking California's Trash – a Proposition 84 Storm Water Grant Program project funded in large part by the State Water Board. BASMAA and its project partners – 5 Gyres, City of Fremont, City of Oakland, City of San Jose, San Mateo Countywide Water Pollution Prevention Program (SMCWPPP), and Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP) provided the match funds.
The primary objectives of the project were to:
This report presents an evaluation of a monitoring protocol (on-land visual assessment (OVTA)) to assess the levels of trash on land (streets and sidewalks) that could reach storm drain inlets as a surrogate for trash discharged from stormwater conveyances. Although several studies have predicted or quantified trash discharges from stormwater conveyance systems, none appear to have attempted to empirically measure reductions over time from this specific trash transport pathway. In the Los Angeles region, trash reductions are currently based on the geographical extent of trash control measure implementation and predetermined trash reduction values for each type of control measure implemented. In the San Francisco Bay Area, trash reductions in stormwater are calculated using three methods. The first two are equivalent to the two methods used in the Los Angeles region (i.e., areas treated by full capture systems and the results of agreed upon control measure specific studies). The third, on-land visual assessment, is currently Bay Area specific. The OVTA is a qualitative protocol that results in observations of trash levels on streets and sidewalks in specific assessment areas. The protocol assumes that the level of trash that is observed on streets and sidewalks is consistent with the level of trash discharged by stormwater conveyance systems. Quantitative monitoring and OVTA assessments were conducted at seven study areas located in the cities of Fremont, Oakland, and San Jose, California. Quantitative monitoring activities included the removal of trash from streets, sidewalks, and storm drain inlets. The trash collected was characterized in terms of weight, volume, and item counts. Quantification events were supplemented with qualitative OVTAs conducted before, after and between street sweeping, and before and after rainfall events. In addition to OVTAs conducted as part of the project, the results of approximately 3,100 OVTAs conducted at roughly 1,200 assessment sites by SCVURPPP and SMCWPPP were utilized to address the project monitoring questions.
This report is one of three technical reports of Tracking California's Trash – a Proposition 84 Storm Water Grant Program project funded in large part by the State Water Board. BASMAA and its project partners – 5 Gyres, City of Fremont, City of Oakland, City of San Jose, San Mateo Countywide Water Pollution Prevention Program, and Santa Clara Valley Urban Runoff Pollution Prevention Program provided the match funds.
This report presents information on developing, testing, and evaluating monitoring methods designed to accurately calculate trash loading rates in stormwater conveyance systems and receiving waters that vary in type, size, flow, and location. Standardized and reproducible monitoring methods to empirically measure trash loading (i.e., flux) in either stormwater discharges or receiving waters have not been available. A literature review was carried out to analyze existing methods and projects that monitored trash within water bodies. The review found that few municipalities and entities in the U.S. have attempted to evaluate concentrations and loads of trash discharged in receiving waters. The biggest source of references was from studies designed to monitor plastic pollution in marine environments, mostly at sea. Methods used during the project were based primarily on NOAA’s Marine Debris Monitor and Assessment Document, Algalita’s River Los Angeles Study, and 5 Gyres’ global estimate that compiled data from multiple partners to determine a global estimate for plastic pollution. These studies suggested that using multiple trawls to capture samples of plastic pollution floating on the surface of a water body, with some focus on what is in the water column, would be the most successful approach. Therefore, methods described in these studies were modified to capture trash samples in receiving waters to accommodate the higher flows observed in rivers, creeks, and channels during wet weather events. Monitoring methods were evaluated in four creeks (three in the Bay Area: Colma Creek, Coyote Creek, and San Mateo Creek and one in Los Angeles: Arroyo Seco, a channelized river in Pasadena).
On June 30, BASMAA convened a biotreatment soil and tree round table to review the current
soil specifications to determine if improvements to the specification can be made to positively
impact the health of trees planted in biotreatment areas. Participants at the Roundtable
included numerous stakeholders: Municipal representatives, compost providers, soil suppliers,
soil laboratory technicians, civil engineers, landscape architects, soil scientists, construction
inspectors, and Water Board representatives.
Specification requires the BSM to be a mixture of sand and compost.