'Brook' in the Bible

Why is my pain unending and my wound incurable, refusing to be healed? You are like a deceptive brook, whose waters cannot be depended on.

And the whole valley of the dead bodies, and of the ashes, and all the fields unto the brook of Kidron, unto the corner of the horse gate toward the east, shall be holy unto the LORD; it shall not be plucked up, nor thrown down any more for ever.