River systems of Thailand divides into two major branches, the " Tiền Giang" (Front River) and "Hậu Giang" (Back River). These in turn enter the South China Sea through nine estuaries. The following are the principal tributaries of Mekong River which flow through Thailand (tributaries entirely outside the Thai border not shown). The Mekong drains a considerable portion of northeast Thailand. In terms of Thai territory drained, it is second only to the Chao Phraya system. The Salawin River rises in Tibet (Tibetan: རྒྱལ་མོ་རྔུལ་ཆུ།) after which it flows through Yunnan, where it is known as the "Nujiang" River (), although either name can be
Course of the Willamette River of Dunthorpe, which is on the left, and flows around Elk Rock Island. Between Dunthorpe and the Sellwood neighborhood of Portland, the river forms the boundary between Multnomah County, on the left, and Clackamas County, on the right. Reaching the city of Milwaukie, the Willamette receives Kellogg Creek from the right and then Johnson Creek from the right slightly above RM 18 (RK 29). Below Milwaukie, the river passes between Sellwood, on the right, and the River View Cemetery, both in Portland, and flows under the Sellwood Bridge, which carries Southeast Tacoma Street. Below the bridge, Sellwood Riverfront Park, Oaks