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PND Hydraulic Engineer Addresses Fish Waste Management in New Textbook


Alex Jefferies takes flow measurements at a fish passage structure on Buddy Creek near Talkeetna.


A chapter by Alex Jefferies, PE, a hydraulic engineer with PND’s Anchorage office, is included in a newly published textbook intended to help educators engage youth in discussions about the past, present, and future role of animals in science education. “Engineering a Solution for Managing Fish Waste” is the third chapter in the book, “Animals and Science Education – Ethics, Curriculum and Pedagogy,” and is one example of animals as the focus of science education. In Alex’s case, her studies led to an engineering solution that contributes to ecosystems, mitigating issues ranging from safety and pollution to odors and aesthetics.

Nathan Harris, EIT, also with the Anchorage office, and Brandi Opsahl, EIT, who joined PND upon graduation but has since moved to Washington, receive a credit in the chapter as well, for contributing to Alex’s fish grinder project while students at UAA, as part of their senior design project.

Alex was approached to write the chapter by Dr. Michael P Mueller, a professor with the College of Education at the University of Alaska Anchorage, after she earned attention for her invention of a fish-waste disposal system. In 2014, Alex was awarded U.S. Patent 8,833,682 B2 for a water-powered fish carcass disposal system, an innovation inspired by growing up on the Kenai Peninsula among fishermen, salmon, and wildlife. She designed a system that floats in a body of water, grinds fish carcasses into pieces, and returns them to the water. The goal is to decrease human-bear interactions by more thoroughly disposing of fish remains that otherwise attract dangerous predators to populated river areas.

Alex graduated from UAA with a bachelor’s degree in civil engineering in 2011, and completed her master’s in civil engineering earlier this year. For her thesis, which focused on fish passage enhancement, she studied a fish passage structure on Buddy Creek near Talkeetna along with the Alaska Department of Fish & Game for three years. She created a two-dimensional algorithm to study juvenile salmonid movement throughout the structure.

While with PND, Alex has designed numerous fish passage structures throughout Alaska including embedded culverts, open-bottom arches, and bridge revetments focusing both on hydraulics and fish passage elements. She is well versed in the latest approaches for improving fish passage through practice and attendance of the latest ADF&G, U.S. Fish & Wildlife Service and U.S. Forest Service fish passage seminars.

The book is the second in the “Environmental Discourses in Science Education” series by Dr. Mueller, Deborah J. Tippins and Arthur J. Stewart. The first, “EcoJustice, Citizen Science and Youth Activism,” explores theory and practice in these emerging areas. Both books are available online in both eBook and printed formats.

PIT (passive integrated transponder) tag antennas housed in PVC (polyvinyl chloride pipe) were installed by the Alaska Department of Fish & Game to detect tagged juvenile fish.


PND Engineers, Inc., founded in Anchorage in 1979, provides civil, structural, arctic, marine, geotechnical, and coastal engineering; hydrology; surveying; environmental permitting; project management; and construction inspection services for a range of projects. The firm has offices in Anchorage, Juneau, and Palmer, Alaska; Seattle, Washington; Houston, Texas; and Vancouver, BC.

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