Morgan Alexander’s letter to the editor last Saturday about the sewage smell on the Ruston Way waterfront got some notice at City Hall. In his weekly report to the council, City Manager Eric Anderson attributed the stink to rotting wood waste from the waterfront’s industrial past:
Interim Public Works Director Mike Slevin reports that the North End Treatment Plant is an advanced primary plant and has an odor control system that was installed in 1997. … Odors are emitted occasionally from the plant premises during the loading of sludge trucks; however, this is fairly minor because the amount of the odor emitting surface area that is exposed to the air is fairly small. Odors can also emanate from the rag bins but these are enclosed and only emit gas to the outside air when the doors to the area are open. This rarely occurs except when the bins are being loaded onto trucks….
Most often odor complaint times match up when Tacoma experiences a low tide. This is because the Mason creek area was once home to at least one large sawmill. Pictures of the area from the early days of Tacoma show sawmills built on piers. At that time, common practice was for sawmills to dump their wood waste (sawdust, bark, etc.) directly into the water. The decomposition of wood waste in salt water, which is a low oxygen environment, creates sulfurous compounds (rotten egg smell).
This decomposition process in a low oxygen environment will take decades. A University of Puget Sound Study conducted several years ago confirmed that most of the odors in the Mason creek area were generated by the decomposing wood waste in the intertidal area.
Public Works has received another complaint that the smell emanates during both low and high tide. In an effort to address these complaints staff are in contact with Mr. Alexander and plans to meet with the other citizen. Additionally, Public Works plans to test the sanitary line in Ruston Way. We will keep you advised as to our progress.