Cocalico Creek
The Cocalico Creek is a tributary of the Conestoga River. It begins in Millcreek Township, Lebanon County and flows for 27 miles until it joins the Conestoga in West Earl Township, Lancaster County. The Cocalico Creek watershed drains an area of 140 square miles. The name is derived from the Lenape word “Gookcalicunk” which means “snake dens”.
Hammer Creek
The Hammer Creek is a 19.2-mile-long tributary of the Cocalico Creek. This places it in the Conestoga River watershed. It originates in Lebanon County and enters Lancaster County in Elizabeth Township just north of the Pennsylvania Turnpike. A dam on the Hammer Creek forms the Speedwell Forge Lake. It joins the Cocalico near Rothsville. The Hammer Creek was named for the sound of the iron forge hammers that could be heard along the valley emanating from the three forges in the Furnace Hills.
Harnish Run
Harnish Run originates on Texter Mountain in West Cocalico Township. It flows into Blue Lake where it joins the Cocalico.
Little Cocalico Creek
The Little Cocalico originates in Spring Township, Berks County. It flows into West Cocalico Township, Lancaster County north-east of Reinholds. It joins the main branch of the Cocalico just south of the Borough of Denver
Middle Creek
Middle Creek is a 15.5-mile-long tributary of the Cocalico Creek. This places it in the Conestoga River watershed. Middle creek originates in Lebanon County near Kleinfeltersville. The stream enters Lancaster County in Clay Township where the creek is dammed to form the Middle Creek Reservoir, famous for the Snow Geese migration each spring. The Middle Creek joins the Cocalico in Ephrata Township.