Upper Nisqually Channel Migration Protection

About the Project

An existing armored revetment owned and maintained by Pierce County within Mount Rainier National Park (MRNP) suffers repetitive severe flood damages during moderate to high flow events. Repairs to the revetment are very costly and continue to mount. Improvements include installing energy dissipating structures along the face of the existing levee.


This Pierce County Planning and Public Works project will reduce flood risk and annual maintenance against the levee in the upper Nisqually near the MRNP entrance area at SR 706. 


The levee will be closed to recreational use as well as the river in the work areas. Improvements will be constructed from July 2021-October 2021.

Contact

Ingo Kuchta
Project Manager
(253) 798-6165
[email protected]

Project Location and Funding

Location

The project area is at Nisqually River Mile: 64.9 – 65.3. Mount Rainier National Park (MRNP) entrance area at SR 706 Highway


Project Area Map_ForWeb


Funding

Capital project, part of the Pierce County River Flood Hazard Management Plan and Capital Facilities Plan.


Benefits & Potential Impacts 

Benefits

  • Reduced flooding impacts to surrounding community
  • Lessen the need for costly levee repairs
  • The structures may also provide ancillary benefits to fish habitat

Potential Impacts

  • The work will involve stream diversions around the worksite to allow the base of the structures to be placed below the active river channel and low enough to resist erosion.
  Project Timeline
  • July 2021: Construction begins. Truck traffic will increase for rock delivery on the in-water construction work
  • October 2021: Construction ends.
Project Updates

Update: Construction is complete with 27 wedge shaped energy dissipating deflectors installed.

During the defishing exercise around 170 Cutthroat Trout, 1273 Sculpins, and 6 Tailed Frog Tadpoles were captured and released.

Planting is expected in December of 2021.

Nisqually Retrofit_01