The Ross Valley Sanitary District (RVSD) was established in 1899 and is one of California’s oldest sanitary districts. It is located in Marin County and serves the communities of Sleepy Hollow, Fairfax, San Anselmo, Ross, Larkspur, Kentfield, Greenbrae, and Murray Park.
RVSD maintains approximately 196 miles of mainline and trunk line sewers and 7.9 miles of force main pipe. These linear assets are stored in a Computerized Maintenance Management System (CMMS) and asset management program that uses Innovyze’s InfoAsset Manager software.
Stephen Miksis, Operations & Maintenance Manager, and John Vogel, Operations Supervisor, have achieved a very successful proactive asset management framework. This framework improved the condition of the collection system infrastructure, controlled infiltration/inflow (I&I), and minimized the number and impact of sanitary sewer overflows (SSOs) that may occur.
Before implementing a proactive asset management program, the wastewater system was experiencing major failures, SSOs, and high I&Is which contributed to prompt the California Regional Water Quality Control Board to issue a Cease and Desist Order (CDO) in 2013.
Since then, RVSD developed an asset registry, performed thorough condition assessments, and used advanced risk analysis to intelligently and effectively manage their wastewater infrastructure.
The RVSD team relies on a CMMS that uses the InfoAsset Manager program to store complaint and blockage records, maintain electronic logs of preventive maintenance activities, and to record issues, identified through regular sewer maintenance activities. This information is used to define and prioritize suitable sewer management activities.
"Within InfoAsset Manager, we track historical information about each pipe segment that is used to help define the six-month priority maintenance schedule. It stores service calls and generates automatic work orders for both regular and six-month maintenances. The results from CCTV inspections, pipe cleaning, and pipe repairs are recorded in InfoAsset Manager and integrated into analyses and reports", Miksis said.
RVSD also implemented field maps which are updated as assets are added, rehabilitated, and as corrections are identified through field work.
Field map updated with all field work, shown in InfoAsset Mobile
"Field personnel used to carry a hard-copy map book that contained the entire sewer system. They now use laptop notebooks with InfoAsset Mobile installed on them: personnel gained real-time reporting and mapping capability and field work efficiency improved", Vogel explained.
"InfoAsset Mobile and InfoAsset Manager sharing the same database has contributed to improving field personnel and office productivity. This means that our processes – including scheduling work orders, reporting while in the field, and synchronizing our asset information back to InfoAsset Manager – are streamlined", Vogel continued.
Pipe repair form completed, and CCTV information entered in InfoAsset Mobile, while in the field
Work orders generated from InfoAsset Manager are used for the system-wide cleaning of all sewer pipes and siphons. When work orders are completed, the InfoAsset Manager database updates with the field reporting instantaneously.
Stephen Miksis uses the recording of cleaning results to help alter the frequency or method of cleaning for manhole-to-manhole pipe segments, to reflect current field conditions.
"This is an important aspect of our sewer cleaning program: we always have a realistic view of the condition of our system. Our teams clean most of the sewer system about every 1 to 8 years. And thanks to the insights we gain from stored asset data, we clean specific portions of the system with known problems on a more frequent basis. Consequently, we are able to minimize maintenance costs, because we can prioritize cleaning activities of the right assets", Miksis explained.
"Our mainline sewer condition assessment program includes CCTV inspection of main line pipes to determine their condition and to detect cleaning requirements. We also investigate all SSOs with video inspections: if an SSO resulted from a main line structural defect, we want to make sure that we prevent that defect from leading to a second SSO. Consequently, we typically make repairs or replacements within one month after the SSO occurred", Miksis continued.
CCTV management within InfoAsset Manager
When conducting pipeline risk‐based prioritization, RVSD relies on its InfoAsset Manager integration with the RVSD Sewer Main Asset Replacement Tool (SMARTool) that was developed in Microsoft® Access. It evaluates the risk of failure for an individual pipe segment, given that asset’s likelihood and consequence of failure. When new CCTV inspections are added in InfoAsset Manager, the SMARTool results are updated with the new CCTV data and risk scores can be assigned to that inspected pipe segment.
Capacity was assessed as part of RVSD’s Infrastructure Asset Management Plan (IAMP). "We utilized the calibrated hydraulic model that was developed using Innovyze’s InfoWorks ICM software for the Sewer Hydraulic Evaluation and Capacity Assurance Plan (SHECAP) project, and applied a 10-year, 24-hour design storm. Pipes were considered under-capacity if the hydraulic model predicted an SSO", Miksis explained.
"We plan to update our hydraulic model and capacity assurance analysis in 2021 to develop a revised list of rehabilitation and capital improvement projects. In the meantime, we have completed extensive capital improvement projects in accordance with the 2013 IAMP and the large diameter sewer condition assessment work of 2014. As a result of this capacity assessment work, SSOs due to capacity have been reduced by 88% from 2016 to 2019", Miksis concluded.
RVSD’s implementation of the risk-based asset management program has enabled the district to lengthen wastewater asset life. It has also provided a decision-making tool, improving decisions made with regards to asset rehabilitation, repair, and replacement.
"With the historical and current information stored in the InfoAsset Manager database, we are able to compare SSO trends from previous years and identify system components that repeatedly contribute to system failures", Miksis explained.
RVSD teams continuously monitor many more metrics: they use dashboards directly within InfoAsset Manager, and they have integrated it to Power BI to create more configurable dashboards. They track KPI metrics related to pipe cleans, incidents, inspections, manhole and pipe repairs, resources, and many more. RVSD constantly leverages these metrics to improve decisions related to their asset management program.
RVSD won Small Collection System Agency of the Year in 2020, for the Redwood Empire Section of CWEA (California Water Environment Association). According to CWEA, this award is "given in recognition of outstanding maintenance programs, regulatory compliance and safety & training procedures".
"We could not be more pleased with receiving this prestigious award, as it is a recognition of our ongoing asset management program success and the continuous hard work of RVSD staff", Miksis concluded.
This case study is based on RVSD’s Sewer System Management Plan (SSMP). For more information, read Ross Valley Sanitary District’s SSMP (PDF).