Related News
Related News
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Community members can test out climate-friendly e-bikes at E-Bike Expo on Saturday
EWEB encourages Eugene residents to ride into summer on clean, accessible e-bikes, with a $300 e-bike rebate.
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EWEB Hosts Dinner to Appreciate Customers of the McKenzie River Valley
EWEB hosted a customer appreciation dinner at the Walterville Community Center on Thursday, May 23, in place of its yearly upriver Board meeting. The event allowed customers, EWEB Commissioners, and staff to share a meal and openly discuss topics most relevant to the McKenzie Valley community.
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EWEB bids a fond farewell to College Hill Reservoir and prepares for modern drinking water storage tanks
Several hundred Eugene residents came together on May 30 for a Farewell Celebration at EWEB’s College Hill Reservoir before demolition and construction to build modern drinking water storage tanks begins later this year.
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EWEB invests in satellite-based forestry analytics for vegetation management
EWEB maintains over 1,300 miles of overhead transmission and distribution lines. To aid crews in identifying hazardous vegetation growth in a sometimes heavily forested service territory, EWEB is utilizing a new satellite-based forestry analytics software called Overstory.
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EWEB opens application for 2024 Electric Mobility Community Grants
Grant awards of up to $30,000 to cover costs associated with electric mobility projects.
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Upgrades to Eugene's downtown electric network continue
You may have noticed construction this week on the corner of 7th and Pearl Street. That’s because crews replaced a corroded, aging vault with an innovative, new Voltek vault. The Voltek design allows for the new infrastructure to be built inside of the existing aging vault. We’re able to install the new vault while the cables are still energized, minimizing disruption to customers and traffic while cutting construction time in half.
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The Big Freeze 2024: After Action Report
Winter 2024 was one for the records books, and we'll look back on it for years to come and say, "That was a doozy!" The back-to-back January Ice Storms caused widespread damage to EWEB’s service territory, affecting approximately 38,000 customers. Preliminary repair costs were over $8 million, and additional repairs to transmission lines are still required.
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Fixing the Unseen: Water Pipeline Replacement in Unincorporated Eugene
Learn more about EWEB's methods for monitoring and replacing aged water pipelines.
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Spring Cleaning? How about Spring Emergency Preparedness!
Spring is officially here and that means the plants are blooming, the sun is (sometimes) shining, and the grass is green! We've had our fair share of severe weather already, but spring weather is notoriously unpredictable. While you're in the midst of spring cleaning and garden care, consider completing these emergency preparedness tasks.
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EWEB General Manager Delivers 2024 State of the Utility
General Manager Frank Lawson delivered his address at the March 5 public Board of Commissioners meeting
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Nine days without power: My ice storm story as an EWEB customer and employee
While beautiful and peaceful, buying a home on the edge of the forest and surrounded by trees has its tradeoffs. Moving “upriver,” I knew there would be more threats to prepare for, including Mother Nature’s seasonal surprises.
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EWEB achieves power restoration milestone over the weekend
Crews have so far restored power for 92% of customers who originally lost power at the height of the ice storm.
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Reenergized McKenzie River Valley transmission lines allow EWEB crews to restore power upriver
On Friday, a majority of EWEB crews tackled power restoration efforts upriver, after federally managed transmission lines were reenergized Thursday.
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EWEB estimates one week to complete power system restoration
On Wednesday, EWEB crews restored power for about 10,000 customers by repairing large equipment first.
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Second round of ice and ensuing thaw prompt mass power outages
On Wednesday, all EWEB crews, who have been working nonstop since Saturday, traversed EWEB’s service territory assessing the damage and restoring transmission lines and main power feeders.
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Monitoring of Trail Bridge Reservoir "Sinkholes" Continues
October 22, 2021
As part of our routine monitoring efforts, EWEB conducted a bathymetric survey of Trail Bridge Reservoir in May 2021. The reservoir is one of three that make up our Carmen-Smith Hydroelectric Project located about 70 miles east of Eugene off of Highway 126 near the headwaters of the McKenzie River.
The results of the survey, which is essentially a map of the topographic features of the reservoir bottom, indicated three "depressions" that required further investigation. One of the depressions was apparent during re-examination of a similar survey performed in 2010.
EWEB conducted follow-up inspections with a remotely operated underwater vehicle along with dye testing by divers in early June 2021. Based on the dye tests, the two larger depressions are actively taking water and are considered sinkholes. Subsequent dye testing and geophysical investigations in July and August indicated that there is no concentrated seepage flow through or under Trail Bridge Dam.
Public safety is EWEB's top priority, and staff are working diligently to manage the safety risk to the public downstream of the dam while actively investigating sinkhole conditions and cause. EWEB's Dam Safety team, along with Generation Operations and Engineering, have been working closely with experienced consultants and the Division of Dam Inspection and Safety of the Federal Energy Regulatory Commission to address the issue and develop a risk mitigation plan.
We have implemented several risk-reduction measures to date, including lowering the Trail Bridge Reservoir level approximately 7 feet below the normal operational elevation, increasing monitoring and surveillance at the dam and downstream, and ensuring effective notification and communication with Emergency Action Plan (EAP) partners.
The decision to lower the reservoir level was made out of an abundance of caution.
EWEB has multiple monitoring devices in place to detect anomalies or any unexpected changes. These include stream flow gauges, reservoir level sensors, groundwater level sensors, turbidity monitoring sensors, remote video cameras with night vision capability and seepage weirs at the toe of Trail Bridge Dam.
"Based on our understanding and the data we have gathered so far, the risk of a catastrophic dam failure is low," said Daniel Huang, EWEB's Chief Dam Safety Engineer. "We will continue our investigation and evaluation, and that could take a year or longer."
Carmen-Smith duty operators conduct daily inspections of the dam, and can further lower the reservoir if any anomalies are detected visually or by the monitoring equipment.
There are plans in place to notify the public, public safety agencies and the U.S. Forest Service should the situation change. There is also a siren at Olallie Campground, downstream of the dam, that EWEB staff can activate should the status of the dam change. The campground was closed in August for the remainder of 2021 due to its close proximity to the Knoll Fire.
The steps EWEB has taken with the increased monitoring and lowering the reservoir level by 7 feet reduce the likelihood of a dam failure. Staff, including engineers, are confident they can quickly intervene if anomalies are detected, which further lowers the likelihood of dam failure.
We will continue to monitor and assess the sinkholes to determine the cause and potential remedies.
Anyone with questions or concerns can contact Joe Harwood at joe.harwood@eweb.org.