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Continuous data graphs Green Lake at Calumet City, IL - USGS-413605087332101
Important for you to know:
- Scheduled Maintenance NoticeUSGS will be performing maintenance on the time series data processing system beginning at 08:00 EST on April 2, 2026. During this period, delivery of the latest time series data will be delayed. The maintenance is expected to finish within 3 hours, after which all backlogged time series data will be processed and delivered to WDFN web portals and APIs.