A Risk-Based Approach to Capital Improvements and Regulatory Requirements

Presentation Description: Ross Valley Sanitary District (District) recently updated its Infrastructure Asset Management Plan (IAMP) to transition out of intensified supervision by the state regulatory agency. The District provides wastewater utility service to approximately 16,000 billing customers, representing approximately 47,000 people in central Marin County. The District has been under a Cease and Desist Order (CDO) from the California Regional Water Quality Control Board (RWQCB) since 2013 due to high storm water infiltration and inflow (I&I) and excessive sanitary sewer overflows (SSOs). The CDO contains a list of prescriptive actions, work practices, and specific capital improvements for the District to mitigate the SSOs and improve operations and maintenance of the sewer system. This also included development of the 2013 IAMP which established the District’s prioritized plan for infrastructure assessment and replacement.
Through implementation of the IAMP, the District has achieved significant capital and repair targets set forth in the CDO. As the District progressed with implementation of the IAMP and collected more data about the collection system, new priorities and decision-making strategies were developed. It became clear that some of the original CDO requirements and priorities needed to shift to a more risk-based approach as the District accumulated more knowledge about the condition of its system.
A major update of the IAMP was completed in 2021 which included significant changes to its operational and capital planning processes to be able to respond more dynamically to changing District renewal and improvement needs. The District has been using the updated tools and processes to periodically analyze capital and maintenance needs to align with District priorities. This presentation describes the key elements of the IAMP process and how they influence utility operations and capital planning at the District. The audience will learn about the innovative techniques used to perform the infrastructure assessments and how the assessments are leveraged to inform capital project prioritization. Finally, a discussion will be provided on how the IAMP has impacted the District’s CDO, and how the District has refined and streamlined its required regulatory actions by demonstrating a more flexible, data-driven approach to prioritizing utility management efforts and resources.