blast furnaces, an open hearth mill, a steel rolling mill, a glass plant, a huge power plant, and an assembly line. During the 1930s, some 100,000 workers were employed here. The plant has been designated as a National Historic Landmark. Main branch The headwaters of the main branch rise in the southwest corner of Rochester Hills and the northeast corner of Bloomfield Township. It flows mostly south through the western part of Troy, and then flows southwest through Birmingham, a noncontiguous portion of Bloomfield Township, Beverly Hills, the southeast corner of Bingham Farms, and Southfield. It then flows mostly south through western Detroit and Dearborn Heights, then turns southeast in Dearborn and continues along the northern edges of Allen Park, Melvindale, River Rouge and the southern edge of Detroit. Other municipalities that are part of the main branch watershed are Auburn Hills, Bloomfield Hills, Farmington, Farmington Hills, Franklin, Lathrup Village, Oak Park, Orchard Lake, Pontiac, Southfield Township, and West Bloomfield Township. Major tributaries of the main branch include: Franklin River (also known as the Franklin branch of the River Rouge) Farmbrook Branches (flow off river into two rivers running into Farmbrook Road & Franklin, Michigan) Pebble Creek Pernick Creek Evan's Creek Upper Branch (see below) Ashcroft-Sherwood Drain Middle Branch (see below) Lower Branch (see below) Ruby Creek Upper branch The headwaters of the upper branch rise in southwestern West Bloomfield Township, the southeast corner of Commerce Township, and the northeast corner of Novi. It forms in Farmington Hills with the confluence of Minnow Pond Drain and Seeley Drain, where it flows mostly southeast through Farmington, Livonia, Redford Township and enters the main branch in the northwest Detroit neighborhood of Brightmoor, Detroit. Tributaries of the upper branch include (from downriver to upriver) Bell Branch Show Drain Blue Drain Bell Drain Tarabusi Creek Minnow Pond Drain Seeley Drain Middle branch The middle branch forms in Northville in northwest Wayne County with the confluence of the "Walled Lake branch" and Johnson Drain. The Walled Lake branch rises in Novi in a marshy drainage area south of Walled Lake, in southwest Oakland County. Johnson Drain rises in Salem Township in northeast Washtenaw County. From Northville, the middle branch flows south through Northville Township and Plymouth Township before turning to the southeast in the city of Plymouth. From Plymouth, it continues through the southwest corner of Livonia into Westland, then along the northern edge of