“Commission” means the state commissioners of water supply appointed under chapter one hundred and eighty-nine, laws of one thousand eight hundred and eighty-two, and their successors however appointed or designated.

“Fresh water” means any fresh water stream, spring, river, or the tributaries thereof, or the waters of any lake, pond, storage reservoir or conduit from which water is drawn, or which is used for furnishing a public water supply.

“Pipe line” means any conduit through which petroleum or any of its products is conveyed or intended to be conveyed.