Team isn’t just a word around here. It’s a commitment.

WSE’s people are extraordinary engineers as well as environmentalists, philanthropists, and humanitarians. We all share strong values that include providing exceptional service to our clients as well as supporting our communities, employees and their families. We always strive to do what’s right.

We are committed to one another and our mission. Meet the team that works together to passionately and expertly care for rivers, communities, clients and each other.


Jeff Johnson, M.S., P.E.

Jeff, co-founder of WSE, is an expert in the fields of hydraulics, sediment transport, and geomorphology, especially as they relate to public safety and natural resource protection.

Larry Karpack, M.S., P.E.

Larry, co-founder of WSE, is a problem solver who loves using his expertise in surface water hydrology and hydraulics to help clients address complex water management issues.

Bob Elliot, M.S., P.E.

With more than 25 years of practical experience investigating the numerous streams and floodplains within the Pacific Northwest, Bob leads WSE's numerical hydraulic modeling program.

Chris Frei, M.S., P.E.

Chris is a senior hydraulic engineer with over 10 years of professional and academic experience working on complex hydraulic and water resource projects throughout the Pacific Northwest.

Dan Scott, Ph.D.

Dan joined WSE in 2018 after completing his PhD at Colorado State University. There, he studied how geomorphic processes regulate wood and sediment storage around rivers.

Sarah Parker, M.S., P.E.

Sarah first joined WSE in October 2014 after completing a Master’s degree in Civil & Environmental Engineering at Colorado State University.

Tim Tschetter, M.S., L.G., E.I.T.

Tim joined WSE in 2016. He is in the process of completing a Master's degree in Civil Engineering at the University of Alaska-Fairbanks with a focus on sediment transport and river mechanics.

Colin Butler, P.E.

Colin joined WSE as a hydraulic engineer in September 2016 after completing his Bachelor's degree in Civil & Environmental Engineering with a focus in hydrology and hydrodynamics at the University of Washington.

Kaleb Madsen, E.I.T.

Kaleb joined WSE in the Fall of 2017 and is in the process of completing a Master's in civil engineering at Washington State University.

Marissa Karpack, M.S., E.I.T.

Marissa joined WSE in 2015 as an intern while she was completing her Bachelor's degree in Civil & Environmental Engineering with a focus in hydrology and hydrodynamics at the University of Washington.

Chris Meder, M.S., E.I.T.

Chris first joined WSE as an intern and returned in early 2020 as a junior hydraulic engineer after completing a Masters of Science in civil engineering focusing on hydrology and hydrodynamics at the University of Washington.