Repurposing Abandoned Infrastructure – (Nearly) Trenchless Parallel Force Main Design and Construction

In the regulatory environment of the San Francisco Bay Area, sanitary sewer overflows (SSOs) are costly infractions that damage the reputation of wastewater agencies, attract unwanted scrutiny from local and regional regulators, and generate unfavorable public relations. For small districts under pressure to consolidate with neighboring agencies, SSOs may signal the end of an independent sewer system. Therefore, maintaining capacity in critical infrastructure is crucial to the survival of small districts, and in today’s economic reality, the ability to find cost effective solutions is equally important. In the context of lessons learned, discussed herein are the planning, analysis, design, sustainability, public outreach, and construction of a parallel sanitary force main by repurposing unused infrastructure via trenchless and conventional installation methods. Benefits of this project include generating beneficial use of abandoned facilities while minimizing environmental impacts and impediments to public travel.