U.S. Geological Survey monitoring milestones—Chagrin River at Willoughby, OH (04209000)

The Chagrin River at Willoughby, OH (04209000), streamgage is the 1,000th U.S. Geological Survey (USGS) streamgage to reach Centennial status. Centennial Streamgages are USGS streamgages that have been in operation for 100 years or more. Collecting water data since 1925, it celebrated its 100th birthday on August 1, 2025.