The Labor Day holiday weekend brought a large number of people to the Brown Bridge Quiet Area to view first-hand the removal of Brown Bridge Dam and the restoration of the original river channel through the east end delta area. For the most part everyone viewed the progress from the designated viewing areas but a few people wandered into the construction area for a closer look. When encountered, these folks were politely asked to please stay on designated trails and viewing areas. No major issues were reported.
AMEC and Molon commenced again early Tuesday morning. They continued to install the temporary dewatering structure using a larger driver. This worked to a degree but Molon is planning to bring in an even larger driver later this week. Most of the sheet piling is within a few feet of their target depth.
Late last week Beirlien completed phase-I demolition of the power house with the removal of the south bay turbine. The head-gate is used to control the pond level which is holding steady at 789.0. As you can see from the above picture of the south bay turbine wicket gates, zebra mussels had pretty much encrusted the gates. The north bay turbine wicket gates are in the same condition. Molon welded a rod to an arm that operates the gates yesterday and used an excavator to move the lever and open the wickets gates to pass water through the north bay. It worked and they used the same process to close the gates again.
As last reported, Molon brought in a much larger excavator and as of yesterday they had dredged close to 45,000 cubic yards. Everything is going well and have actually opened part of the new river channel to flow. There’s some question about how to handle some really fine sediment under the East Overlook. Project engineers and managers from AMEC, Inter-Fluve, and Molon are currently determining the best course of action to dredge the new river channel in this location. Overall everything is proceeding very well.
Please contact me if you have any questions.
– Steve Largent, Boardman River Program Coordinator