Mill Creek (Delaware River tributary)

Mill Creek (also known as Otter Creek) is a 11.04 mi long tributary of the Delaware River and is one of six streams in Bucks County, Pennsylvania by the same name. Mill Creek rises just east of Core Creek Park in Middletown Township and reaches its confluence at the Delaware River's 118.87 river mile in Bristol Borough.

History
In 1885, the "Atlas of Properties Near the Philadelphia and Trenton Railroad" by G.M. Hopkins, give Mill Creek shows the stream from its source to the confluence with Queen Anne Creek (Mill Creek) as Mill Creek, but, below that as Otter Creek. Some modern maps show Mill Creek all the way to the Delaware except that the estuary itself is labeled as Otter Creek.

The east branch of Mill Creek is also known locally as Black Ditch Creek.

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

Silver Lake appears to have been created around 1701 after a dam was built in 1687 to power a mill in Bristol. Due to the rust-colored water, baths were built beginning in 1773 and completed in 1801 as it was thought to cure many diseases. Silver Lake has been dredged a number of times to remove silt.

In March 2023, approximately 8,000 gallons of "latex finishing material" leaked into Otter Creek. The material leaked from a pipe at a Trinseo plant. Residents of Philadelphia were advised to drink bottled water on March 26, as there was a chance tap water may have been impacted.

Statistics
The watershed of Mill Creek is 19.80 sqmi, passing through residential, commercial, and industrial areas, much of the path of the creek lies in Levittown, Pennsylvania. The Geographic Name Information System I.D. is 1181137, U.S. Department of the Interior Geological Survey I.D. is 02916.

Course
Rising just east of the Core Creek Park at an elevation of 160 ft, 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. Then it turns to the south for a distance to the Mill Creek Valley Park. 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. At the 2.00 river mile, Mill Creek flows into Silver Lake which discharges Mill Creek at the 1.33 river mile, thence meet its confluence with the Delaware River at an elevation of 0 ft. The average slope of Mill Creek including the west branch is 14.49 ft/mi.

The east branch rises with two branches near the Falls Township Lake. After a short distance to the southwest, it meets a branch that connects with the Pennsylvania Canal (Delaware Division), then continues variously south and southeast to its confluence with the west branch in the Black Ditch Park.

Named Tributaries

 * Queen Anne Creek
 * East Branch Mill Creek

Municipalities

 * Mill Creek, main branch
 * Bristol Borough
 * Bristol Township
 * Mill Creek, western branch
 * Bristol Township
 * Middletown Township
 * Mill Creek, eastern branch
 * Bristol Township
 * Falls Township

Public Parks

 * Main Branch
 * Silver Lake County Park
 * Black Ditch Park
 * western branch
 * Mill Creek County Park