Nothing in this chapter shall affect any existing water rights, riparian, appropriative, or otherwise; nor shall it affect existing rights relating to the operation of any hydroelectric or water storage reservoir or related facility; nor shall it affect any exploratory work, construction or operation of a thermal power plant by an electric utility in accordance with the provisions of chapter 80.50 RCW. Nothing in this chapter shall enlarge or reduce the department of ecology's authority to regulate the surface use of waters of this state or structures on the underlying beds, tidelands or shorelands.