Recreation equipment is often stored in parks for the convenience of people participating in team sports.
W4 Street Basketball Courts
If you can have private lockers parks for team sports I think this creates a good precedence to have shared public lockers in parks that hold recreation equipment for people with special needs
I suspect this is already done in some locations, in an article on the ADA Jay Beckwith says the following...
Another solution is providing a “mini-adventure playground.”
This can be as simple as creating a designated area surrounded by a low
fence and placing a lockable storage area within this zone. To reduce
theft or vandalism, the storage can be chain link with a combination
padlock the combination to which is provided to parents who agree to
idea. Filling the storage with wooden boxes, planks, cable spools, and
other play-useful but low value items is all that is needed to complete