Source Molecular Corporation’s Dr. Yiping Cao was one of the invited speakers at the Exfiltration Workshop hosted by the California Association of Sanitation Agencies (CASA) and the Southern California Association of POTWs (SCAP) on October 1, 2018, in San Diego.
Dr. Cao, who is Source Molecular’s Vice-President of Technology, discussed Types of Human Fecal Matter Indicators together with Dr. Michael Trapp of Michael Baker International, a provider of engineering and consulting services. Dr. Trapp introduced indicators used to date while Dr. Cao talked about the human fecal-associated HF183 marker. The HF183 is considered to be the most effective marker of human fecal contamination.
Dr. Cao related that the HF183 marker was used to establish a human fecal contamination score (HFS) for ranking recreational sites by quantitative real-time PCR method. By having a standardized HFS, water managers can prioritize which sampling sites to remediate based on measured human waste levels. Same mathematical algorithms can be applied to other markers to provide for example cow fecal score and gull fecal score (collectively called Host Fecal Scores).
Brandon Steets, a Senior Principal Water Resources Engineer at GeoSyntec, also presented details about their Santa Barbara Study, State of Knowledge on sewer infrastructure exfiltration.
SCAP Executive Director Steve Jepsen noted that water quality from urban runoff continues to be an issue, including bacteria from human sources. However, there are little or no direct funding sources for stormwater quality programs. Mr. Jepsen added that stormwater quality practitioners and scientists don’t always understand collection systems, leading them to point to Sewer Exfiltration/MS4 Infiltration is a prime suspect in bacteria impairment issues. “We need to get out in front of this issue and educate the regulators and stormwater quality practitioners,” he said.
Other speakers and panelists were Melissa Thorme of Downey Brand, Paul Causey of Causey Consulting, Michael Flores of HDR, and Steve Stuart, Dr. Don Marrin and Bryn Evans of Dudek.
SCAP is an association of cities, special districts and other public agencies, which was formed to concentrate its resources to effect reasonable local, state and federal regulations impacting POTWs and collection systems.
CASA’s membership includes engineering consultants, service and technology providers, accountants, attorneys and financial institutions. It represents over 100 public agencies that engage in the collection, treatment or disposal of wastewater, resource recovery or water recycling.