Best to check the website for availability.
There is a lot of info at the State park website at https://cpw.state.co.us/placestogo/parks/BoydLake
There are shower and restroom houses at the main beach area but I think all of that is closed up for the winter.
I believe there are showers a available year round although it is limited to A loop or something most the loops are closed this time if the year
To bathe there is in the summer but I think it is open all year round for fishing and other things.
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