network utility operator

means a person who—
(a) undertakes the distribution or transmission by pipeline of natural or manufactured gas, petroleum, or geothermal energy; or 
(b) is an electricity operator or an electricity distributor as defined by section 2(1) of the Electricity Act 1992 for the purposes of any works as defined by that Act; or (c) undertakes the piped distribution of potable water for supply; or 
(d) is the operator of a sewerage system or a stormwater drainage system

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