The Naturalization of Line D (New Ohlone Creek) is a transformative flood– control initiative in Newark, California, led by the Alameda County Flood Control and Water Conservation District in collaboration with Ohlone Community College. Originally constructed in 1958 as a straight earthen channel, Line D suffered repeated bank failures. This project reimagined the channel into a meandering creek and dynamic floodplain system, applying fluvial geomorphology principles to create a self-sustaining, climate-resilient waterway.
The adjacent Ohlone College campus, home to an Environmental Studies program, provided a unique opportunity for educational synergy and ecological restoration. The redesigned creek enhances flood protection, ecological value, and public access while supporting student engagement with natural systems.
ENGEO provided hazardous materials services throughout design and construction. This included site exploration, health– risk assessments, and preparation of remedial plans reviewed and approved by the Department of Toxic Substances Control (DTSC). ENGEO also oversaw the removal of approximately 3,900 cubic yards of impacted soil and submitted a completion report to the DTSC.
The project faced complex environmental and logistical hurdles, including impacted soils requiring offsite disposal, artesian groundwater conditions, and sensitive receptors. Additionally, multiple staff transitions at the DTSC added regulatory complexity. Despite these challenges, ENGEO maintained project momentum through technical expertise and close coordination with project partners.
