the river on its left bank from Corvallis to Albany. Below Corvallis, the Dead River enters from the right at Half Moon Bend, from the mouth. About downstream, a side channel called the Kiger Cutoff, in concert with the main channel, helps form Lower Kiger Island. Below the island, the river reaches Bowers Rock State Park at RM 123 (RK 198), where Bowers Slough enters from the left and the Little Willamette River enters from the right. On the opposite bank from the state park, the much smaller Hyak County Park is on the left. As the river reaches Albany, the Calapooia River enters from the right from the Willamette's mouth. Bryant Park is on the right, and a USGS stream gauge is just beyond the confluence, where the combined rivers flow under the Ellsworth Street Bridge and then the Lyon Street Bridge, which carry U.S. Route 20 eastbound and westbound, respectively. The gradient is slightly steeper in these upper reaches than in the reaches between Albany and Oregon City. Albany to Oregon City In Albany, the river flows east under a Union Pacific railroad bridge and through the city, then curves north by a series of industrial ponds as well as First, Second, Third, and Fourth lakes, which are on the right. At RM 113 (RK 182), Wilson Lake is on the right, and about further downstream, the Willamette leaves Benton County and becomes the boundary between Linn County, on the right, and Polk County on the left. Roughly later, the river leaves Linn County and becomes the boundary between Polk County on the left and Marion County on the right. The Santiam River enters from the right from the Willamette's mouth, and the Luckiamute River enters from the left slightly below the mouth of the Santiam. About later, the river reaches Buena Vista County Park and the unincorporated community of Buena Vista, both on the left, and the Buena Vista Ferry, which carries vehicles using Buena Vista Road between Polk and Marion counties. Below the ferry crossing, the river goes around Wells Island and receives Rock Creek from the right at RM 104 (RK 167). Through the next stretch, Ankeny National Wildlife Refuge is on the right. The river then passes Tyson Island and Murphy Bar before passing under a bridge carrying River Road South in Independence, where Riverview Park is on the left about from the mouth.