[2] Lake Magnolia was originally a soil borrow site during the Pennsylvania Turnpike construction decades ago.

Due to the rust-colored water, baths were built beginning in 1773 and completed in 1801 as it was thought to cure many diseases.

[9] Rising just east of the Core Creek Park at an elevation of 160 feet (49 m), the west branch of Mill Creek flows generally south-southeast to its 9.69 river mile just east of Langhorne Manor where it meets an unnamed tributary on the right bank.

Making an S-bend, at the 5.14 river mile, it then joins with Queen Anne Creek then flows south until its adjacent to Interstate 276 Pennsylvania Turnpike where it makes a hard left at the 3.07 river mile to flow east into the Black Ditch Park where meets with the east branch of Mill Creek.

The average slope of Mill Creek including the west branch is 14.49 feet per mile (2.744 m/km).