Mud Mountain Dam
This project replaced an existing fish trap and haul facility downstream of the Mud Mountain Dam to protect homes and businesses in the lower White River and Puyallup Valleys from flooding, and provide fish passage to current standards while mitigating complex habitat and infrastructure needs. Osborn Consulting (Osborn) was responsible for the Care and Diversion Work Plan and the Temporary Environmental Controls, and the temporary diversion of the river flow and fish passage during construction. The Care and Diversion Plan for the river documents each phase of construction, hydraulic modeling for both scour design and fish passage requirements, environmental compliance, and a fish monitoring plan.
USACE Seattle District & Cascade Water Alliance
osborn’s plan shaves 20+ months off construction
The plan Osborn developed to efficiently phase and isolate the work area shaved 20+ months off the construction schedule and enabled USACE to use the new facility for the 2021 Pink Salmon run, which is a bi-annual fish run that historically overwhelmed the old facility.
osborn’s access road design helps avoid delays
Osborn developed the design for the access road leading to the trap and haul facility. Originally planned as a two-lane road that transitioned to a one-lane road due to the surrounding topography, a Value Engineering Change Proposal (VECP) was submitted to consider widening the road to include two lanes for the entire extent. The new design avoids delays in the movement of fish hauling trucks or emergency vehicles and removes the need for signal lights on the access road. Instead of the costly fabricated elevated walkway that was initially proposed, the new design was able to accommodate a simple paved pedestrian path along the whole length of the access road.