Big Rapids, city (1990 pop. 12,603), seat of Mecosta co., W central Mich., at the falls of the Muskegon River; inc. 1869. Agriculture and light manufacturing predominate, and Big Rapids serves as a shipping point for the region's grains. Extensive natural gas wells are nearby. Ferris State Univ., part of the Univ. of Michigan system, is in the city.