Question: On the new elevated connection to I-5 from eastbound Highway 16 – the one that goes over Center Street and South Tacoma Way – I notice that some of the supports are concrete while others are big old rusty steel columns. Why are they using different materials? – Robert, Tacoma
Answer: The parts of the highway supported by steel columns are just temporary, set up to handle traffic while the new east-bound Nalley Valley viaduct is being built. The sections of roadway over the concrete columns are parts of a more permanent plan.
According to the Washington State Department of Transportation, some of the sections supported by steel columns will stay in place for as long as eight years. Then traffic will be switched onto the permanent structure, and the temporary detour will be demolished.
Have a question about traffic congestion, construction, spending or other transportation issues? Send it to email@example.com. Include your name, hometown and daytime telephone number. We’ll answer as many as we can.