lake bed
lake bottom

Her home, according to what little he knew, was probably at the bottom of the lake.

They could have been standing on the lake bottom, too.

The bottom of the lake: that had been the Wall.

"I just thank God it's not your body down at the bottom of the lake, too."

The ball stopped at the bottom of the lake that is 50 feet behind the green.

But it was at the lake bottom and did not offer to rise.

This created an opening in the bottom of the lake.

But something was stirring at the bottom of the lake.

Under the surface at the bottom of the lake there is ice age water.

Whatever it was, his feet never touched the bottom of the lake.