The Silting-up Question.

Te Aroha News, Volume XXVI, Issue 43090, 9 May 1907, Page 2

The Silting-up Question.

Same time ago the Ohinemuri County Council instructed Mr James Stewart C.E., to prepare a report on the effect of the deposit of iniuing debris in the Ohinemuri River. The report was read at the last meeting of tho Council, and t the conclusions ari'ived at were as fol- J lows : —(A) Prior to abmt ten years ago, ’ comparatively little harm or damage to the river or to the farming interests lias taken place. But shortly after that period it became evident to those more immediately interested that the evil results of the river being a sludge channel ■ was a growing and serious menace to the i district. In consequence, early in I Q OI, ] the attention of the Government was 1 called to the matter.

(B) The report of Mr Perham, deputed to examine the case, confirmed in many important respects, the allegations of damage to the rivers and lands. But it is very evident that had he ever thought it likely that an increase of the deposits from the mines, to an extent of nearly threefold, would take place during the next six years, with a monthly increment of increase of 2,000 cubic yards, he would have supported them on all points. (C) The beds of the rivers from Mackay town downwards show a serious rise on the whole, but not uniformly, and the shoals formed are shifting downwards with every flood, and gradually damag ing the main river. (D) That the rise of the bed in the Ohinemuri was the cause of the unprecedented level of the flood in January last, resulting much damage to the adjacent lands, by the deposit of sand, and otherwise. (E) That the outlet drains get choked by sand, and although they are afterwards more or less scoured out of their own impounded water, obstruction to the drainage must follow. (F) That the successive deposits on the broad meadow lands of even thin layers of fine quartz sand (which has about the same fertility as that of broken glass) will, if continued, effect their destruction as grazing lands, and convert them into wastes of blowing sand. Mr Stewart recommended as follows • I agree that the alternative of returning the whole of the tsilings to re-fill the stopes in the mines is impracticable, but in part not so, as it seems to me quite possible tnat at least one half might be passed down with the other fillings without danger either to the stability or salubrity of the mines. All this will no doubt be held by some to amount to a proposal to seriously obstruct the mining industiy, but it is only a question of expense, between the mine-owners and the general community, if forced to the work of dredging. I am aware also that by many the mining industry is held to be paramount. That is a question which I must leave to others But at a time when it is seriously proposed to com meuee the arterial drainage on the great low lands in the Thames and Piako Valley, it seems anomalous that a system should be continued which would to a largo extent render nugatory a scheme of such importance from a national point of

view. MR PERHAM’S REPORT

In July, 1901, a report, accompanied by plans, was submitted to the Government by the late Mr Thomas Perham, UE. In a map accompanying the report ha indicated the accumulations of tailings in the bends of the Oliinemuri, and show a length of the Waihou of about two miles below the Junction as required to be dredged. Mr Perhuiu’s report also stated that, while admitting the fine quartz sand “ has tended to raise and narrow the river bed, it is not so serious as is generally represented by the farming interests ” He further stated that

“ the artificirl drainage of swampy low country tends to materially raise the beds °f _ the rivers by the deposit of alluvial Soil and vegetable debris.”

MR PEED’S REPORT. In a report furnished to the Government by Mr F. Reed, Inspecting Engineer of Mines, of date 27th Auguftlast, that official says that “ no further silting up of the river, between Paeroa and Nether!on, has apparently taken place since the visit of Mr Perham, in 1901.”