"Note: There are no bathrooms and\or Porta-Potty’s up there, so if you’re bringing the wife\GF or kids be prepared."
Actually there are quite a few that are available on all sides of the lake. Here's a few....google the locations:
Big Bear Lake Visitors Center (24/7)
Meadows edge picnic areaBig Bear Discovery Center
Boulder Bay Park
Meadow Park, big Bear
Miller Park, Fawnskin
Here is a link to a lake map that shows lakeside facilities, public access and restrooms:
http://www.bbmwd.com/lake-map/
These are just a few but there are plenty more.