OMC Moves Forward with "Soldier Pile Wall” Structure
OMC Board Approves Est. $290,000 for Project to Minimize Topsoil Erosion
Olympic Medical Center’s flagship building – Olympic Memorial Hospital – arguably has one of the best views in Port Angeles. Sitting atop the bluff on the Strait of Juan de Fuca, patients may gaze out at the water (or alternatively the Olympic Mountains) when they are hospitalized.
With recent sloughing and sliding of the waterfront bluffs across the North Olympic Peninsula, some have been left to wonder about safety of the bluff behind the hospital.
"We have been monitoring the stability of the bluff for years, and as we have updated and expanded the hospital, we have implemented slope protection measures,” says Scott Bower, plant operations and construction manager, Olympic Medical Center. "What’s more important to note is Olympic Medical has been incredibly diligent in monitoring the bluff and mediating potential issues.”
The hospital building sits on hard glacier-packed soil (better known as hard pan or glacial till), and monitoring reports show the foundation of the bluff has not moved since Olympic Medical officials began monitoring more than 20 years ago. The building is well protected from slides resulting from weather, tsunamis or average earthquakes.
Alternatively, the topsoil on the bluff has been shown to weather and erode at a fairly nominal rate. To mitigate potential loss of topsoil behind the hospital on the bluff, Olympic Medical’s board of commissioners approved building a retaining wall – called a soldier pile wall – to protect topsoil on the slope from erosion.
"The retaining wall is a cost-effective and reliable way to ensure the top soil stays put behind the hospital,” says Bower. "Although our infrastructure near and on the bluff have other safety features in place to protect against slope erosion or other potential disasters, the soldier pile wall adds another layer of protection.”
Work on the soldier pile wall is expected to begin this summer using the small works roster at an estimated cost of $290,000.
During construction of the retaining wall, a protective barrier will be placed for safety at the bottom of the slope between the hospital and the Olympic Discovery Trail. "We want to ensure the safety of trail users during construction,” says Bower. "We do not anticipate any need to hinder access to the waterfront trail during the project.”
Bluff Last Monitored in March 2015
Olympic Medical has engaged Northwest Territories, Inc. (NTI) to monitor the bluff off and on over the past 20 years. In 2014, OMC hired NTI to install a bluff monitoring system to allow for annual evaluations, with the most recent report completed in March.
While installing the monitoring system in 2014, NTI and Bower took a closer look at a slide to the west of the hospital. The slide was due to topsoil movement, and a soldier pile wall was recommended to prevent similar topsoil erosion behind the hospital property. The retaining wall was ultimately approved for the 2015 capital improvement budget. "We take the safety of our patients and staff, this includes the maintenance of our infrastructure, extremely seriously,” says Bower. "We are pleased to begin work on this project that will mitigate future risks to topsoil erosion and help our community members feel at ease about the condition of the bluff behind the hospital.”