18. No expropriation under this division shall take place except in the case of a water-power of an average natural force of at least 150 KW and large enough for industrial purposes, nor shall such right in any case be exercised to the prejudice of an industry already established or of water-works supplying the territory of a municipality wholly or in part.
R. S. 1964, c. 84, s. 18; 1977, c. 60, s. 2; 1996, c. 2, s. 862.