Hydraulics engineer Dennis Mekkers redesigns rivers in order to save endangered fish species

Seattle District U.S. Army Corps of Engineers hydraulic engineer Dennis Mekkers’ clients are not your typical engineering firm clientele. He often finds himself answering to the environmental needs of endangered salmon rather than to the demands of corporate bigwigs.

A graduate of the University of Washington, Mekkers completed his civil engineering degree in 1995 and a master's two years later, and quickly landed a position with the Seattle Army Corps of Engineers. Mekkers admits he entered the field of engineering for the job security. But after studying civil engineering, the 35-year-old found a way to mix interests in the social sciences with engineering by pursuing a career in hydraulics and hydrology. "I really would have liked to have been a sociologist or anthropologist as a first preference, but it dawned on me that a career in the social sciences might not be the most practical way to make a living," he says. "The practice of civil engineering [is] an excellent avenue through which to render meaningful services to society."

In 2000, the Washington state native completed the first dam removal project for the Seattle District–the Goldborough Creek Dam located in Mason County near the city of Shelton, Wash. Mekkers was responsible for identifying a hydraulically feasible approach for the $4.5 million restoration of the creek.

"The channel had degraded substantially over the years, so removal involved dismantling the dam and restoring the stream gradient with a series of weirs, or grade control structures, in a fashion similar to a stairs-landing-stairs approach," says the former president of the University of Washington's American Society of Civil Engineers student chapter. "Weirs are designed to be passable by salmon and to minimize adverse downstream impacts, such as excessive sediment transport and/or induced flooding."

In the past, Mekkers has evaluated the hydrologic behavior of wetlands, supported the Corps' Floodplain Management services program and been involved in dam safety inspections and investigations. He is currently working on a fish passage facility for the Howard A. Hanson Dam Additional Water Supply project. Located on the Green River in King County, Wash., the $50-million project will provide downstream passage for juvenile chinook, coho, and steelhead salmon. Additional water will be stored for municipal and industrial use by the city of Tacoma and for low-flow augmentation.

"Seattle District is a federal entity with extensive environmental, regulatory, and water resources-related responsibilities over a large geographical area," Mekkers says. "Endangered Species Act-related issues are prevalent throughout our jurisdiction and we must bring an environmental awareness to bear on everything we do." In June 2001, Mekkers was honored by Corps as the Seattle District Engineer of the Year in recognition of his work on past projects for the district. An active member of ASCE's Seattle section, he recently took over as chairman of its Water Resources Technical Committee.

Mekkers plans to develop his hydraulic engineering skills and assist in advancing hydraulic understanding to be more consistent with society’s present and future water resource needs.