After more than a decade of planning, the City of Newport’s Big Creek Dams Project
is set to kick off its detailed design phase. This significant development in the project is enabled by $4 million in initial funding from the Oregon State Lottery funds. At its August 21 meeting, City Council approved a contract with HDR, an engineering firm, to begin designing a replacement dam. Design is expected to take several years, and construction will require additional state and federal funding.
The City has known that the dams could fail during a seismic event since 2010, and
more recent inspections have shown the problem is worsening. Yet, a long-term solution
is extremely costly and beyond what the City’s residents could afford without significant
government funding. Newport’s Big Creek Dams were built decades ago. The lower dam was completed in 1951, and the larger upper dam was added in 1968. Both dams are earthen, forming an embankment constructed by compacting successive layers of soil and gravel to form a core and placing more permeable materials on the upstream and downstream sides.
These dams were common then but not constructed to withstand seismic events. Only
within the last 20 years has Oregon been recognized as an area susceptible to sizeable
seismic activity.
Newport is home to 10,755 year-round residents and attracts 2.5 million visitors
annually. Complete failure of the Big Creek Dams would cause a loss of the drinking water
source for an indefinite period, potentially resulting in loss of life and financial losses that
would exceed the cost of the proposed project to resolve the issue. HDR will design a single concrete dam between the upper and lower reservoirs, and their work will also provide an updated cost estimate for construction. The new dam would be higher than the existing dams and hold the volumes currently stored in the lower and upper reservoirs. The additional storage would address future water supply needs for the community.
The current lower reservoir would be reduced or removed to address safety
concerns, and the existing upper dam would be lowered, overtopped by water, and
incorporated into the new area of the upper reservoir. Over the coming months, residents living near the reservoir and those who recreate there may notice early signs of surveying and research activity, including equipment on roadways. “We want residents and visitors to the area to be aware and informed; we are taking some initial steps on the project, including bringing in equipment, in the coming weeks,” said City Engineer Aaron Collett.
“We are excited to have the funding and the engineering firm to get the design underway,
and we will be proactively sharing information and continuing to address our community’s
questions,” he said. “Most importantly, we want to ensure everyone’s safety.”
The City is building a resource for current information on the project and expects to
have a project website online in the coming months for residents to get updates.
Questions may be directed to Aaron Collett, at a.collett@newportoregon.gov
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