I have never seen camping around the lake area. I don't believe that it is allowed. There are however several camp sites further up Guanella Pass Road that you can use and are within walking distance from the lake.
The lake is about a 1 mile walk down the road (no sidewalk) but its worth it- bring a hat and sunglasses! There are several shady spots but get there early or you'll end up in one of the 2 spots in front with no shade at all
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