Connoquenessing Creek
View of the Connoquenessing Creek from Renfrew, Pennsylvania
Location
Country	United States of America
State	Pennsylvania
County	Beaver Butler Lawrence
Cities	Butler, PA, Harmony, PA, Zelienople, PA, Ellwood City, PA
Physical characteristics
Source	Oneida Lake and Dam
• location	Butler County, Pennsylvania
• coordinates	40°59′32″N 79°52′11″W / 40.99222°N 79.86972°W / 40.99222; -79.86972[1]
Mouth	Beaver River
• location	Ellwood City, Beaver County, Pennsylvania
• coordinates	40°51′13″N 80°19′13″W / 40.85361°N 80.32028°W / 40.85361; -80.32028[1]
• elevation	735 ft (224 m)[1]
Length	57.76 mi (92.96 km)[2]
Basin size	839.79 square miles (2,175.0 km2)[3]
Discharge
• location	Beaver River
• average	1,123.10 cu ft/s (31.803 m3/s) at mouth with Beaver River[3]
Basin features
Progression	Beaver River → Ohio River → Mississippi River → Gulf of Mexico
River system	Beaver River
Tributaries
• left	Bonnie Brook, Thorn Creek, Glade Run, Breakneck Creek, Brush Creek
• right	Sullivan Run, Little Connoquenessing Creek, Scholars Run, Camp Run, Slippery Rock Creek

Connoquenessing Creek is a tributary of the Beaver River, approximately 50 mi (80 km) long, in Western Pennsylvania in the United States.

Course

Connoquenessing Creek rises in eastern Butler County and flows southwest, through the Lake Oneida reservoir and past Butler, then west-northwest in a meandering course past Eidenau where Breakneck Creek is received, and then continuing past Harmony and Zelienople. It receives Slippery Rock Creek from the northwest near Ellwood City, then joins the Beaver west of Ellwood City, approximately 3 mi (5 km) further downstream.

Watershed

In 2000, a scientific study was conducted to determine the health of the creek. Researchers discovered that only the Mississippi River received more toxic materials than the Connoquenessing, making the small river the second most polluted waterway in the United States. "The Armco Inc. steel facility in Butler, purchased last September [1999] by AK Steel, ranked first nationally for the amount of pollutant discharges. The steelmaker legally discharged more than 29 million pounds of nitrate compounds -- a waste produced when nitric acid is used to "pickle" or clean the surface of raw steel—into Connoquenessing Creek."^[4]

However, as of 2010, the Connoquenessing Creek was not listed in the national Top 10 for polluted waterways. Also, as of 2010, Armco Inc. steel in Butler was not listed in the Top 20 in regards to national pollutant dischargers.^[5]

The creek is a popular canoeing and kayaking destination, with many boaters entering the creek at various locations.