Steve, estes park has a few local rivers, but they are small and will be too low to float when you are here. They are the Big Thompson and Fall River.
The colorado river pumphouse section (mostly class II, one III-) will be running then due to dam release and its a popular float trip. Its a few hours from estes park, but its a nice day trip. The lower blue is class III and is dam release feeding into the colorado river and might be running then too.
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