Artesian Contamination By Sea Water Doubted

Press, Volume CVII, Issue 31521, 8 November 1967, Page 25

Artesian Contamination By Sea Water Doubted

The possibility of salt-water contamination of artesian bores near the coast was scouted by the City Engineer (Mr P. G. Scoular) at a meeting of the Christchurch Regional Planning Authority yesterday. The question was raised by Mr D. B. Rich, who said there were reports of pollution in some artesian bores, and some authorities believed that there could be contamination from the sea. “There is no possibility of salt getting into the artesian water,” said Mr Scoular. “To the south-west, there have I been peculiar analyses of the; water, and it is suggested that this could be caused by very, diluted sea water. “If it is, it is in a peculiar place. If it was sea water, it | would change our thinking asi to where the water comes I from.” The director of planning; (Mr C. B. Millar) said that! there was a suspicion of salt* in some shallower wells; but; evidence was lacking to sup-1 port a restriction on well-| sinking. The authority approved a! technical report on ground I water, which said that in the. Christchurch area, wells took! 25m gallons a day, and j springs removed 50m gallons a day. “While pressures have drop- j ped slightly, there is no evi- 1

rjdences as yet to suggest that 11 the supply is failing,” the re- , port continued. “There is no ’evidence that the Christ- _ | church supply will fail to pro- ' | vide for future needs, although new wells must in- ’ j creasingly tap deeper water . | layers. E | “In areas where ground I ; water supply is not feasible.] ,’the Waimakariri is a satisfactory alternative. The cost of [ such a service, though higher j than present costs, will not be for water-supply to ! j act as a restraint to urban development.” , j Extensive urban develop- ] I ment west of Christchurch. ! the report stated, could rejduce rain-water intake, but ] this would cause only a slight fall in levels.