By Michelle Fillingim
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December 16, 2024
Alan Kropp and Associates is proud to have led a team of consultants on behalf of the Alameda County Flood Control and Water Conservation District (ACFCD) on the Naturalization of Line D (New Ohlone Creek) project. The project was recognized by the American Public Works Association (APWA) with a Project of the Year Award in the Category of Environmental Projects $5 Million to Less than $25 Million at the 2025 APWA annual conference in Chicago. The New Ohlone Creek project represents an innovative and sustainable approach to flood control. It transforms a conventional, man-made trapezoidal flood control channel into a dynamic, natural floodplain system. Line D was originally constructed in 1958 as a single objective earthen channel. However, that straight line channel experienced repeated bank failures, and in its quest to find a more permanent solution than patch riprap repairs, ACFCD sought a more environmentally sustainable solution. The project reimagined the flood control channel as a New Ohlone Creek, a meandering creek traversing a broad floodplain. The project took advantage of vacant land belonging to the Ohlone Community College District (OCC) immediately northwest of the channel, and, with the adjacent OCC campus hosting the College’s Environmental program, it provided a synergy and opportunities for students to learn more about natural systems. This design leverages principles of fluvial geomorphology to create a natural equilibrium channel that can adapt to changes in climate and watershed conditions. By expanding the channel floodway and allowing the creek to meander, the project effectively contains flood flows within the channel banks.
