Marylhurst Pump Station Replacement Project
The current station has aging equipment with expensive repair and maintenance costs, and is unreliable in emergencies. It has a history of overflow events and there is no permanent back-up power currently at the site. Access into the pump station dry well (underground pump and electrical controls chamber) is by an elevator within a 3-foot diameter entrance tube and is considered “confined space entry”., Therefore, access is restricted which makes it difficult to maintain the station. Also, below grade electrical equipment is vulnerable to flooding.
The project will involve replacing the existing 37-year old pump station in the same location. New high efficiency pumps will be installed and equipment will be configured differently to provide safer access for operations and maintenance staff, and bring the station up to current standards. A permanent on-site generator will be added to increase the reliability of the pump station. Electrical panels will also be placed within an above-ground building for security and protection. The project team has incorporated neighborhood feedback into design of the architectural features of the building and landscaping.
In September 2016, the City of Lake Oswego hired a consultant team – Murraysmith - to conduct the design for replacement of the Marylhurst Sewage Pump Station.
The Marylhurst Pump Station was constructed in the early 1980s and is the city’s second largest station. It has a service area of 347 acres, which is 83% residential (more than 1,200 households).
The pump station is located along the westerly bank of the Willamette River, at the north end of Old River Road near Glenmorrie Drive, adjacent to the river pathway.
The City awarded a public improvement contract to R. L Reimers Company in January for construction of the project.
Major construction is expected to begin in late March/early April and take about six months to complete. During this time, Old River Road will be closed to through traffic, and a detour will be in place. Most of the time, the pathway will remain open but it will be shifted around the active work zone. There will be a short time when the pathway between George Rogers Park and the pump station will be temporarily closed to all pedestrians, but this will be minimized.
The new pump station will look different from what it is today. The community provided input into the design, which includes a new electrical control building, generator, native landscaping, guard rail and ornamental railing along the pathway. The existing boulders, pavers, plaques and artistic bollards will also be reused and repurposed on site.
Design is complete and the City plans to request bids from contractors to construct the project through mid-December.
Due to lead times for procuring materials and equipment, construction is not expected to start until spring 2019.
Once begun, work is expected to take about six months to complete. During construction, Old River Road will be closed to all traffic at the pump station site, except emergency vehicles, and a detour will be in place.
An open house was held on January 10, 2018 to share information and gather feedback on site landscaping and architectural features for the new electrical control building. View the displays here and the comment summary.
Design is currently underway on the replacement project. An open house will be held on January 10, 2018 where the project team will share information and gather public feedback on site landscaping and architectural features for the new electrical control building.
Wednesday, Jan. 10, 2018
6:30 – 8:30 p.m. (drop by anytime between these hours)
17600 Pacific Hwy.,
Boards will display alternate architectural materials, landscaping and hardscaping features proposed for the project. Input and feedback received at the open house will enable the team to refine the final design before submitting a land-use application to the city’s planning department.
Design and permitting are expected to continue through summer 2018; construction is anticipated to start in fall 2018.
The project team presented an overview and update about the design of the project to the Glenmorrie Neighborhood Association on May 23, 2017. The slides are available here.
From October 3 through October 7, 2016, as a part of the pre-design work for the project, crews will drill 5 or 6 strategically located test holes along the Willamette River Pathway between the lower parking lot of George Rogers Park and Old River Road. The pipeline from the Marylhurst Pump Station, that conveys wastewater to a manhole in Furnace Street, is buried along the entire length of the pathway. The borings will help to determine the ability of the pathway and footbridges to continue supporting the pipeline during a significant seismic event. To maintain safety, the pathway will be closed to public use, 24/7, during those five days.
Surveying and other topographic fieldwork will also be conducted during early October 2016.