Eau Claire (ō klâr) [key], city (1990 pop. 56,856), seat of Eau Claire co., W central Wis., on the Chippewa at the mouth of the Eau Claire River, in a hilly lake region; inc. 1872. Once a lumber-based economy, the city now has diverse manufacturing, including tires, processed foods, dairy and paper products, and automotive controls. A trading port was there in the late 18th cent. The city grew from several sawmills established on the Eau Claire River in the mid-1800s. It is the seat of the Univ. of Wisconsin at Eau Claire and a technical institute. Carson Park, on a nearby peninsula, contains a memorial to logging days.