A: Safety is our highest priority: There is not an imminent danger of a canal breach. EWEB staff carefully monitors the performance of the Leaburg Canal throughout the near-term risk mitigation process and the longer-term Triple Bottom Line Assessment. Because the canal is not carrying the large amounts of water that it conveys for power generation [2500 cubic feet per second (cfs)], the risk of a potential failure is greatly reduced. EWEB will monitor the canal in the wet weather season and during storm events when tributary creek flows rise. These creeks, including Johnson Creek, Cogswell Creek, Hansen Creek, and others, deposit their waters into the Leaburg Canal, and then the canal conveys those waters back to the McKenzie River. EWEB staff members are poised to identify and respond to any unexpected developments along the full length of the canal and will inform canal neighbors of any changes of concern.
A: EWEB is evaluating the canal on a near-term, risk reduction basis to mitigate the risk of structural failure from landslides, earthquakes, floods, and erosion. These measures include:
• isolating portions of the canal from the high flow creeks, such as Johnson and Cogswell Creeks,
• removing hazard trees above the canal that may fall during a storm and obstruct the canal, causing water to pool up and potentially flood or cause an undue burden on the canal embankment
• installing pressure transducers that monitor water levels and trigger alarms if water levels extend beyond our currently desired levels
• deploying LIDAR and developing a drilling plan to better understand the canal’s structure and critical subsurface conditions.
A: While implementing the near-term risk reduction efforts, EWEB is conducting a Triple Bottom Line Assessment to identify the financial, environmental, and social impacts of long-term repairs to the canal. This TBL assessment will help Commissioners decide the alternative future services of the canal. The principal decision is whether EWEB should invest in a “Return-to-Service” of the canal as a hydroelectric generation facility, or to decommission the project and reconfigure its “Stormwater conveyance” function.
A: The Leaburg Project is currently out of service. In order to bring the Leaburg Project back online - to “Return-to-Service” – EWEB Commissioners must calculate if it is worth the investment to repair the canal’s structural issues to the extent that it can reliably convey enough water (2500cfs) to generate. Along with the financial costs, there are environmental and social costs to consider, such as the impacts of large construction projects to the Leaburg community, closures to recreation facilities during maintenance, fisheries concerns with diverting water from the McKenzie River into the canal, the carbon footprint associated with the project work, etc.
A: The Leaburg Project has a rated capacity – its maximum ability to produce energy – of 15.9 Megawatts (MWs). But like most other energy generation resources, Leaburg rarely produces the maximum amount possible. Assuming normal water supply conditions, Leaburg can produce, on average, 92,000 MWhs of electricity per year, which represents 4% of EWEB’s annual electricity demand – or enough electricity to power about 13,000 average single-family homes.