Summer Sat and Sunday, bring a picnic!
Go in the morning - 9.00 am or so. More boat traffic in/out of the locks. No salmon now - but the fish ladder later in the year should be cool.
The days prior to seafair or opening day are excellent as there is a lot of boat traffic.
Mid-late May is when Salmon are running. Also, many Spring festivals at the park. Locks, Salmon ladder, and botanical gardens.
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