Yes there is. https://jcprd.com/Facilities/Facility/Details/Shawnee-Mission-Park-Beach-75
There is a dog park that allows dogs to swim in the lake for free. I have seen people get in there before but would not recommend as there is no lifeguard.
There is a daily fee or a swim season membership for the beach. The beach is the place at the lake where swimming is permitted. There are life guards on duty.
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