Gresham trestle upgrades

Capital Improvement Project
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We have strengthened the structural supports (known as trestles) that hold a water pipe near Kelly Creek and Beaver Creek in Gresham. This project is part of our commitment to preparedness and our mission of serving excellent water every minute of every day.
Fall 2020 to spring 2021 (vegetation monitoring continues through 2024)
Location Description
Powell Valley Neighborhood, Gresham
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Project overview

Not if, but when... You've heard about our region's earthquake risks. The Water Bureau has worked for the past several decades to increase the number of water supply facilities that can withstand earthquakes. The Gresham trestle replacement project is part of our commitment to preparedness and our mission of serving excellent water every minute of every day.

Through this project, we strengthened the structural supports (known as trestles) that hold the water pipe that runs along Kelly Creek and Beaver Creek in Gresham. Both the pipe and trestles were installed here in 1911. While the pipe is in good condition, but the trestles might not endure a large earthquake or heavy flooding. The work we've completed makes Portland's and Gresham's water supply more resistant to earthquakes and floods.

As part of the project, we removed trees and other vegetation to allow equipment to access the trestle. Because of this, we developed an extensive restoration plan with oversight from the City of Gresham. Now that construction is complete, crews have landscaped the entire lot with native trees and plants that will improve the health of the creek. 

Map showing restoration areas, including: easement area restoration later this spring (yellow on map), planting temporary cover crop spring 2021, and planting native trees, shrubs and grasses winter 2022 (pink on the map), monitoring and caring for existing plantings through 2024 (green on map)
Restoration plan map

Happening now

We have finished strengthening the trestle that holds the water pipe running along Kelly Creek. This means that Portland's and Gresham's water supply is now more resistant to earthquakes and floods.

Construction may be complete, but we're sticking around. Our planting team will be coming by to weed and monitor vegetation in the area through 2024. Growing a healthy greenspace will take a little time, but we're committed to leaving Kelly Creek better than we found it.

Ongoing restoration: Winter 2022 –spring 2024

  • Plant trees and shrubs in the construction area as needed to ensure the area thrives.
  • Continue monitoring and maintenance
Images of trees to be planted on site, including (left) cascara, (top right) Western hemlock, and (lower right) Western red cedar.
Trees planted during revegetation include cascara (left), Western hemlock (top right), and Western red cedar (lower right).
Pictures of the different types of grasses that will be used in re-seeding the open space to prevent erosion, including (left to right) Blue wildrye, slender hairgrass, and California brome.
Photos of native grasses that were planted in the area, including (left to right) blue wildrye, slender hairgrass, and California brome.
Photos of native shrubs that will be planted in the area including Snowberry (top) and Thimbleberry (bottom).
Photos of native shrubs that will be planted in the area, including snowberry (top) and thimbleberry (bottom).

Image credits

Map