ONONDAGA CAVE STATE PARK Wastewater Treatment Plant, Crossroads, Missouri

ONONDAGA CAVE STATE PARK is a wastewater treatment plant located in Crossroads, Crawford County, Missouri, United States. The facility serves a small population of 200 people, reflecting its role as a park-based treatment system. It is situated in a rural area near the Meramec River basin. The plant provides secondary treatment, which is the standard level required by the US Clean Water Act for municipal wastewater facilities. With a designed capacity of 22.71 cubic meters, the plant operates at full capacity based on reported discharge volume. As a small facility, it is likely subject to state-level NPDES permitting under the Missouri Department of Natural Resources. The treated effluent is discharged into local waterways that drain into the Meramec River, a major tributary of the Mississippi River. The plant's location in a state park underscores its importance in protecting the natural environment and recreational waters of the area.

The plant discharges into the Meramec River watershed, which flows into the Mississippi River and ultimately the Gulf of Mexico. The Meramec River supports diverse aquatic life and is a popular destination for recreation. The plant's secondary treatment helps protect water quality in this ecologically sensitive region.