The Blackwater River
is a tributary
of the Lamine River
, about 55 miles (90 km) long, in west-central Missouri
in the United States
. Via the Lamine and Missouri
Rivers, it is part of the watershed
of the Mississippi River
The Blackwater River is formed by short north and south forks in Johnson County
about 6 miles (10 km) northwest of Warrensburg
and flows generally east-northeastwardly through Johnson, Pettis
Counties, past the towns of Sweet Springs
. It flows into the Lamine River in northwestern Cooper County, about 4 miles (6 km) southeast of Blackwater.
Several sections of the river's upper course have been straightened and channelized.