[4] The highway travels east into downtown Marysville on 4th Street, crossing over a section of the BNSF Railway's Bellingham Subdivision (which also carries Amtrak's Cascades passenger trains) near Comeford Park and the city's landmark water tower.[3][8] The highway continues east on 4th Street and crosses Allen Creek, a tributary of Ebey Slough with large wetlands.[17] The state government widened the westernmost 1⁄2 mile (0.80 km) of SR 528 between I-5 and Columbia Avenue to 60 feet (18 m) and installed traffic signals in 1972.[19] A connection for the two sections of SR 528 was planned in the late 1960s by the state government and approved for construction in 1969,[18] but was delayed until the 1980s due to a lack of available funds from a federal program.[28] The westernmost section of the highway through downtown Marysville was rebuilt in 2008 as part of a repaving project that also replaced a set of water mains.[35] A long-term plan from WSDOT and the Tulalip Tribes proposes adding a set of roundabouts to replace the traffic signals in and around the interchange.