When the accommodation fundamentally changes the nature of the program, it need not be made. The sport of sand volleyball is an example. A player in a wheelchair cannot maneuver in the sand. But, the sand can be paved to allow a player who uses a wheelchair to play volleyball. But then it becomes volleyball, not sand volleyball. Paving the court is not required. Other accommodations though may be effective. One example is lowering the net and requiring all players to play sit-volleyball.
Hint: public entities, if denying an accommodation because it is an undue burden, must make a memo to file that describes the request, why it was denied, and options considered.