The Stratton Lock will open for the 2017 season on Wednesday, May 3.  IDNR lock tenders will operate the Stratton Lock on Wednesdays and Sundays from 10:00 a.m. until 10:00 p.m., and on Thursdays, Fridays and Saturdays from 10:00 a.m. until midnight through October 29.  The lock will be closed on Mondays and Tuesdays (with the exception of holidays) for the 2017 season.  The Stratton Lock is also closed for the winter season each year from Nov. 1 through April 30.”

https://www.dnr.illinois.gov/WaterResources/Pages/StrattonLockandDam.aspx