The Washington State Department of Transportation (WDOT) is moving forward with the State Route (SR) 520, I-5 to Medina: Bridge Replacement and HOV (high occupancy vehicle) Project. This effort will replace the SR 520 floating bridge, approaches, roadway and interchanges from I-5 to the eastern shore of Lake Washington.
WDOT has been continuing the in-water portion of geotechnical investigations of the areas surrounding the planned bridge structures west of the floating bridge, and should have them completed in a couple weeks (in-water and on-land investigations began in 2011). This portion of the in-water study provides valuable information to engineers and contractors as they design foundations for the new bridges. A small crew will use a drill rig mounted on a barge to complete the work.
The drill rig will sound similar to background noise from the highway. Area residents also may hear an occasional hammering sound during soil sampling. When in use, the noise generated by the soil-sampling equipment may reach up to 70 decibels, which is similar to the noise levels of highway traffic when standing approximately 50 feet away. All work will occur during daylight hours.