Yes. For example, there is the remarkable dolphin species in China's Yangtze river. It's known variously as the Wuhan Baiji Dolphin, and the Chinese River Dolphin. It's particularly interesting because it's NEARLY BLIND, with eyes that protrude a bit and seem to face upward a bit. It's thought to have come to its current river habitat roughly 20,000 years ago. It's nearly extinct-- roughly 13 individuals are currently alive. It's the world's most-endangered cetacean, and is expected to become extinct sometime in this decade, despite an active preservation project. Its habitat is steadily changing and disappearing because of the "3 gorges" dam project, normal river pollution, tons of SOUND pollution from heavy boat-traffic, and mortality from the expected collisions with all that boat traffic. More info: http://en.wikipedia.org/wiki/Chinese_River_Dolphin This variety of dolphin should NOT be confused with the pink dolphin (a.k.a. "white dolphin", which is NOT a true fresh-water dolphin. The pink (white) dolphin lives in China, but generally lives in shallow ocean water, not in rivers. There are roughly 1,000 living white (pink) dolphins

there are also freshwater dolphins in the amazon river

I'm just elaborating on michelle_d's answer. The Amazon river dolphin has a strange hump on its back, and the head flows less smoothly into the "beak". It is nearly blind, and hunts using echolocation.

The December 14th episode of Geraldo at Large discussed the white dolphins - Baiji Dolphins, a rare fresh water dolphins that live in the rivers of china. Unfortunately the review was discussing their extinction. There may be 2 or 3 left in the river but most likely will not survive due to hunting and pollution. Every year the local Chinese have a dolphin hunt where over hundreds are slaughtered pointlessly, in a pool of their own blood. These dolphins, I believe they are called Baiji dolphins. They have a long straight nose and have been around for thousands and thousands of years.