Lake Lou Yaeger is a 1,300-acre (5.2 km²) reservoir located in Montgomery County, Illinois. Created by damming the West Fork of Illinois's Shoal Creek, it was built for recreation, sport fishing, and flood control purposes. The lake is 8 miles (13 km) long and 0.5 miles (0.8 km) wide. The nearest town is Litchfield, Illinois, south of Springfield, Illinois and north of St.