The Chicago Harbor Lock, located in Chicago and adjacent to Navy Pier, separates the waters of Lake Michigan from the Chicago River. It is one of two entrances from the Great Lakes to the Illinois Waterway System. And, according to its Lockmaster Selwyn Tyrone Valley, last year it hit a milestone. “In terms of lockages and vessels, we were the busiest in the nation,” Valley said. “We had about 10,000 lockages, and saw an average of 1.16 million passengers, and almost 62,000 vessels.”A 16-member team operates the lock 24/7. There are 10 operators, a lockmaster, a facility manager, a mechanic, an electrician, a facility services assistant, and an information technology specialist