Collection System Improvements to Effectively Reduce SSOs

Abstract

In 2003, the Clark County Water Reclamation District (District) assessed their practices, procedures, equipment and systems utilized at that time to manage the District's wastewater collection system. The goal of the assessment was to identify gaps between the District's practices and industry best practices for managing wastewater collection systems. The outcome of this process was a Collection System Assessment Report. Since the completion of the 2003 assessment, the District implemented several of the recommendations and a number of key stakeholders at the District have also changed. The 2006 Collection System Services project updates the 2003 assessment and included high-priority initiatives for immediate implementation focused on sanitary sewer overflow (SSO) reduction and mitigation. These high-priority initiatives included: 1) An Updated Developer-installed Infrastructure Inspection Program and District Outreach to Stakeholders, 2) Standards for Pipeline and Manhole Inspections and Implementation of Contracted Inspection Work, 3) Cleaning Workload Required to Clean the District's Entire System and Implementation of Contract Cleaning Work, 4) Costs, Estimated Flows, and Plausible Systems for Diverting Dry Weather Flows from Streams Through the District's Water Reclamation Plant (WRP), 5) Integrated Computerized Maintenance Management System (CMMS) Scope and Budget for Implementation. In addition to these immediate high-priority actions, to address recent developments and provide for long-term, proactive improvement in the District's wastewater collection system, this project included additional analysis and updating to identify key opportunities for improvement in the following areas: 1. Asset Databases; 2. Collection System Odor Control; 3. Rehabilitation and Replacement capital improvement projects (CIPs); 4. Prioritized Cleaning Program; 5. Lift Station Operation and Maintenance; 6. Regulatory Reporting Practices; and 7. Other Key Opportunities. District staff selected key opportunities from the updated Collection System Assessment Report for implementation over a 5-year planning horizon and an Implementation Schedule was developed based on the priorities set by the District. The plan includes a budgetary estimate of the cost for the implementation of each initiative; including a staffing and equipment plan. This paper presents a summary of the key features of the District's collection system improvement plan to reduce SSOs. As a result of the first year of the program, collect system SSOs have been reduced 27 percent.