The Portland Water Bureau and contractor Hoffman Construction Company have officially begun an eight-year capital improvement project to update the Washington Park reservoir site at 2403 SW Jefferson Street. The project complies with federal and state mandates, seismically strengthens key water infrastructure on Portland’s west side, and helps ensure a healthy, resilient, and secure water system.
You may have seen on the news, read articles, or observed while driving by that crews are currently in the process of mitigating and removing trees and vegetation in and around the reservoir project site in Washington Park.
The Portland Water Bureau wants to ensure you have the most updated, accurate, and complete information.
SAFETY IS OUR TOP PRIORITY
The traffic plan spanning now until March 2018 has been approved by the Portland Bureau of Transportation. The Water Bureau will be conducting evaluations and adjusting traffic flow as conditions require. The Water Bureau is working with Portland Parks & Recreation, Explore Washington Park, neighborhood associations, and the community to gather on-the-ground feedback and determine if changes are necessary. Please provide your traffic and signage feedback by phone, e-mail, or on the dedicated webpage.
DECEMBER 2016 ACCOMPLISHMENTS
General Site Work
• Shoring wall along Sacajawea – construction has begun on the first retaining wall along Sacajawea Blvd. The wall will stabalize the hillside and, once complete, will allow better construction access while the new reservior is being constructed.
• Existing Reservoir 4 – work has begun to perforate the liner of Reservoir 4. Both dams and gatehouses will be preserved.
• Access ramp into Reservoir 3 – 1,016 tons of gravel are being used to build a temporary access ramp into Reservoir 3. The ramp is 150 long and
100 feet deep. All gravel will be reused on the project when the ramp is removed.
• Installation of large pipelines under Dam 3 – these pipelines will serve as the outlet lines of the new reservoir as well as serve an integral part of the project’s drainage system. The 48” pipes are more than 100 feet underground.
• Erosion control at the site is ongoing.
• Existing Reservoir 4 concrete liner will be perforated to allow for drainage. As part of the project, existing Reservoir 4 will be buried, making room for a large stormwater bioswale and wildlife habitat area with open water and connecting walkways.
• Existing Reservoir 4 basin will be filled in order to stabilize the historic landslide. Excavated material from Reservoir 3 will be moved inside the project work site to fill Reservoir 4. This will dramatically reduce construction impacts and truck traffic to local neighborhoods.
• Shoring wall construction along Sacajawea will continue through the winter. Two shoring walls will be constructed, one temporary and one permanent, to protect the site from earth movement and allow for construction of the underground reservoir.
OCTOBER 2016 ACCOMPLISHMENTS
General Site Work
- Tree protection fencing has been installed to minimize impacts during construction.
- Vegetation and trees have been removed from in and around the project site. Of the approximately 210 trees removed, 19 percent (40 trees) are non-native/invasive. Roughly 47 percent (80 trees) of the healthy, non-invasive trees removed will be used in river restoration projects in the Sandy River Basin. These projects will help create pool habitat, increase cover, and improve spawning beds for migrating, spawning, and rearing fish populations. Several trees were also delivered to the Oregon Zoo for use in primate exhibits. After construction is completed, the Water Bureau has committed to plant 20 percent more trees and shrubs than required.
Reservoir 3 & 4 Work
- Existing Reservoir 4 inlet and outlet piping has been disconnected.
- Existing Reservoir 3 Grand Staircase has been partially removed.
- Gatehouse 3 platform has been removed.
- The plastic liner in Existing Reservoir 3, originally installed in the 1970s and later replaced in 2003-2004, has been removed.
SEPTEMBER 2016 ACCOMPLISHMENTS
General Site Work
- Construction trailers for project team members to work, meet, and manage the project have been delivered and installed.
- The Portland Bureau of Transportation approved traffic control plan spanning Sept. 12, 2016 to March 2018 was successfully implemented. The plan includes road closures, parking changes, a traffic flow reversal, and a multi-use shared path for pedestrians and cyclists along with more than 130 signs, reader boards, and flaggers to maintain a safe, uniform flow of traffic in Washington Park.
- Vegetation and trees are in the process of being removed from around the project site. Of the approximately 210 trees to be removed, 19 percent (40 trees) are non-native/invasive. Roughly 47 percent (80 trees) of the healthy, non-invasive trees removed will be used in river restoration projects in the Sandy River Basin. These projects will help create pool habitat, increase cover, and improve spawning beds for migrating, spawning, and rearing fish populations. Several trees were also delivered to the Oregon Zoo for use in primate exhibits. After construction is completed, the Water Bureau has committed to plant 20 percent more trees and shrubs than required.
Reservoir 3 & 4 Work
- The wrought iron fencing surrounding Existing Reservoir 3 and 4 has been removed. Portions will be rehabilitated off‐site and incorporated into the redeveloped surface water feature. Prior to removal, the fence was photographed, documented, tagged, inventoried, and specially packaged for protection so that it could be taken off site for restoration, some for repurposing, and all for protection during construction.
- The construction fencing surrounding the site has been installed.
- The Weir Building, constructed in 1949 to screen water, has been removed. Its removal will provide the necessary space to build shoring that will in turn support the underground reservoir construction.
- Large equipment is mobilizing on site for the installation of two shoring walls, one temporary and one permanent, to allow excavation for the new seismically reinforced underground reservoir fortress.
Please see below or visit us online and click on Tree & Vegetation Mitigation & Removal.
Tree and vegetation mitigation and removal is scheduled to occur Sept to early-Oct. 2016.
Trees and vegetation are being removed for a variety of reasons, including:
- Room to move equipment in/out of project site
- Trees’ proximity to the construction zone
- The building of the new underground reservoir and shoring walls
- Removal of ailing trees
- Removal of trees that would be severely damaged during construction
- Removal of non-native/invasive species trees
The Tree Protection, Preservation, and Removal Plan is posted online.
Approximately 209 trees will be removed from in and around the site.
- None of the trees are old-growth
- 40 trees (19 percent) to be removed are non-native/invasive species trees
- 80 (47 percent) of the healthy, non-invasive trees will be used in river restoration projects in the Sandy River Basin as part of the Bull Run Habitat Conservation Plan (HCP). These projects will help create pool habitat, increase cover, and improve spawning beds for migrating, spawning, and rearing fish populations over 2.6 miles of stream.
Certain trees will be mitigated and fenced for protection.
Some of the tree’s root balls within the project limit will be left in the soil for stability.
After construction is completed, the Water Bureau has committed to plant 20 percent more trees and shrubs than required.
More About the Project
A new 12.4 million gallon, seismically reinforced below ground reservoir will be constructed in the same footprint of existing Reservoir 3 (upper) with a reflecting pool/water feature on top. The new reservoir will preserve the historic drinking water function provided by the original reservoirs and be engineered to withstand ongoing landslide encroachment and potentially catastrophic effects of a major earthquake.
When complete and online, the new reservoir will supply water to Portland’s west side and serve more than 360,000 people, including all downtown businesses and residents, 20 schools, three hospital complexes, more than 60 parks, and the Oregon Zoo.
Existing Reservoir 4 (lower) will be disconnected from the public drinking water system and a lowland wildlife habitat area, bioswale, and reflecting pool will be constructed in the basin.
Construction has started and will proceed through 2020. A pause in construction is scheduled to occur from 2020 to 2022 to allow soils to settle. From 2022 to 2024, construction of interpretive features, including the two reflecting pools and surface features, will conclude the project.
Construction will proceed through 2019. A pause will occur from 2020 to 2022 to allow soils to consolidate to reduce any vertical movement. From 2022 to 2024, construction of interpretive features, including the two reflecting pools and surface features, will conclude the project.
The next project e-mail update is scheduled for September 2016. Please contact us with questions, concerns, or to change your preferences to receive project updates.
- Reach us by Phone: 503.823.7030
- Write us an E-mail: Lindsay Wochnick
- Visit us Online: portlandoregon.gov/water/wpreservoirs