NATURE HITS BACK

Evening Post, Volume CVI, Issue 107, 2 November 1923, Page 7

NATURE HITS BACK

HARNESSING MANGAHAO

BRIDLE AND BIT NOT YET IN PLACE

DAM SITE AT LAST PUMPED DRY.

FLOOD LEAPS BARRAGE AND DESTROYS WORK.

In a country of limited population and geographically remote from the large industrial centres, big contractors do not grow like mushrooms; and, apart from all questions of political policy, New Zealand has necessarily had to rely on a Construction Department established by the Government. •In this connection, the Department of Public Works has performed a service the complexity and value of which are probably not realised by the people. Where such realisation exists, no one would think of withholding from the Department a full measure of praise. FRONTIERSMEN IN A DOUBLE SENSE. Public Iworks in New Zealand are necessarily carried out in a remote part of the earth—in an insular State which has almost everything in Nature to commend it, but which cannot draw on the labour l-esources of a continent (as_ an American contractor can), and which is divided by thousands of miles of sea from the industrial centres that supply technical equipment, such as the modern earth-moving machinery that may compensate to some extent for scarcity and dearness of labour. Public works in New Zealand not only have to contend with such difficulties as arise from the general geographical isolaI tion,of the country. In addition, they are often sited in the most remote and inaccessible parts of the country. itself. The Public Works engineer's place' is generally more or less on the frontier, and sometimes near the sky-line. Consider Otira (over 2000 feet high) and Mangahao (altitude about 1200 feet). And consider their approaches. OBSTACLES—AND THE TIME 'FACTOR.. Men who have worked at Otira and Mangahao, with their extraordinary records of temperature, or snow, or rainfall (or all combined), know the New Zealand climate as no city-dweller knows it. And they know, a 3 few others know the. cost m human effort of breaking in the wilderness; of uniting East and West with a five-mile tunnel through' the Southern Alps, eight miles of railway electrification (peculiarly susceptible to damage from certain natural conditions), and ever so miles of groynes and riparian-protective works • of carrying, an eastern river through the backbone range to its western side, by means of dams and tunnels, and makin" the same river fall about 900 feet in order (inter alia) to drive tramcars in Wellington. Let these things be remembered when we try to lecture' the Public Works Department on the time-factor, and when we quote American contractors' speed records. Most relevant to this thought is the three-shift hustle now in evidence at Mangahao hydro-electric works. And most eloquent is the response of Nature who has instituted a counter-hustle— abnormal in springtime even for Mangahao— as though she were aroused to defend herself against the liberties which engineers are taking with her configuration and her river system. THE RIGHT SORT OF RIVER— WHEN BRIDLED. In "The Post's" specfal hydro-elec- ' tncal article on Wednesday, the heading appeared "Taming of the Torrent." The story printed below shows the tremendous resistance that the Mangahao torrent offers to the tamer; and illustrates why the harnessing of a fastrising mountain river, addicted to the sort of gorges that provide dam-sites, is a slow and costly affair. There, is one consolation—the hydroelectrical engineers are certainly not finding any lack of the essential water The damage done to construction works as the Mangahao, swollen with the mountain rains in its upper basin rages through its bottle-neck gorge, foreshadows the mighty power that will be exerted in the service of man when the harnessing is complete.