Never swam or paddled in Lake Tahoe before.  Checked online and deepest part of the lake is 1644 feet.  That is deep.  Just slightly saline, which means it is more like fresh water than salt water and less buoyancy when you swim.  Water temperatures in the summer are in the 60's which is cold if your body temperature is 98.6 and you are immersed more than a few minutes in the lake.  There is not much of a safety factor if you fall in Lake Tahoe from a boat or kayak and do not have a life vest.  After quite a few deaths in Lake Tahoe, including Ma from Hawaii, should be required equipment for any boater or kayaker to wear a life vest and neoprene wet suit or partial wetsuit to increase survival time by reducing the rate of hypothermia.