I'm not sure the status of the falls right now. I was out that way in mid August and they were still flowing well. You might be able to put in a call to the Ranger Station there and get a report.
Another good day hike if you stay around Lee Vining is the Twenty Lakes Basin at Saddlebag Lake Trailhead (photos:
http://flic.kr/s/aHsjBBSHcA ). You can find a lot of information online about that hike. I don't have my trip report ready yet for it. There is some rough terrain, but it is only about 4 1/2 miles. If you want to just explore and sight see, there is always Bodie Historical State Park (Photos:
http://flic.kr/s/aHsjtuLegs ). Depending on the state of the Aspen Trees, June Lake Loop (south of Lee Vining) and Lundy Canyon (North of Lee VIning and great beaver ponds) are other places to check out (not a lot of hiking, but great scenery, Photos from that area:
https://www.facebook.com/media/set/?set ... 3670d8f69e). There is one trail I've been meaning to take off of the June Lake loop and that is Parker Lake. It looks to be a fairly strait forward hike and nice in the fall if the Fall Colors are alive. It is on my short list for the next time I get out to that area.
Enjoy!!