The Wangaehu River.

Auckland Star, Volume XVII, Issue 201, 27 August 1886, Page 4

The Wangaehu River.

(To tho E

iter.)

Sir,—A letter from Mr X. W. Gudgeon, respecting the recent change in the character nf the Wangaehu water, and su gesting

the introduction of salmon and trout into tho purified river, has been copied from your paper into this evening's " ' anganui Herald," and as the letter contains several errors, correction may not be out of place. 1 happen to know the river throughout its whole course, so can speak positively on the subject. The source of the Wanguehn is on tho X.E. slope of Ruapehu, a lew chains from that of the Waikato, and they sei-m to (low from the .-ame stra'.um of the mountain, though they turn in opposito directions, and have, till now, had such widely dissimilar water. It is generally supposed that tho actual erigin of tho Wungaehu is a small lake in an old crater, tho wator o; which has lately beon boiling, aud that it is the overflow of this lake which, at a certain level, percolates through the mountain side and supplies fie spring, the hiko water having the same thick milky appearance as that of the stream. Tho stream water is so utterly nauseous that its flavour will remain in the mouth for hours, and it taints tbe river, both in taste and colour, right down to tho sea, though it dots not amount to anything iike a thousandth part of the whole volvme that flows in tho lower river. It is only, howevor, in late summer and early autumn, when trie tributaries are low, that the foul water produces any very appreciable effect on the whole. During fully ten months of the yoar the river water is drinkable, even within a few miles of its source, though it is certainly not palatable, and has purgative and anthelmintic properties that make it valuable me jicinally. The idea that the VVangaohu contains no fish is entirely erroneous. Whitebait, smeit, &c, ascend it every year, and in Novem her and December quantities of young eels may always bo seen working their way out of it into its tributaries. In fact, few streams so abound with eels as these ratne tributaries, particularly the lower ones, the river water being least contaminated in the late autumn, when the largo eels are making their way to the sea to breed ; and in the spring, when tho young fish are coming up from tho salt water. Upokororo, Patiki, Papunoko, and Kokopu, occur also in the river, though not abundantly ; and a variety of eel-pout, very like a brown trout in its markings, seems peculiar to it and its tributaries. Lven in (he lower pare of its course, below its junction with the Mangawhoto and Mangamahu, it- has a vi_ry swift current; end above this last stream, it is almost ono continuous rapid tight up to its'source, it having a fall of about -1,000 feet in a distance (along its windings) of about 150 miles. It is, in fact, the most turbulent river iv this part of the colony. 1 think that tho purification of the water is only temporary, and arises from the lako water being dissipated in steam, instead of percolating through the mountain side ; nnd that the phenomenon has actually occurred before, though it was not noticed ut ■ tho time. At the end of lSb- the north east peak of the mountain was steaming or smoking for several weeks, and shortly afterwards the sulphureous stream ceased to flow for übout three months. This probably arose from the boiling of tho lako water, but as no one happened to ascend to the part of the mountain from which the lake is visible, the cause of the failure of tho stream was not suspected. As it occurred in autumn, wheu there was little snow on the mountain, the stream simply went dry ; now, however, tbe melting of the snow, probably to a greater extent than usual, owing to the increased heat of tho mountain, keeps up the volume of water in tho stream, though in a pure instead of impure condition. I doubt if salmon would thrive in tho Wangaehu, as they seem to need pure water; _ though they might do so in its great tributary the Mangawhero, into which trout wero introduced several years ago, as well as into another largo one, tho Tokiaburu, near the base of Ruapehu. I may mention that the steam and smoke lately observed issuing from Ruapehu proceeds, not merely from tbo crater' lake, but from othor parts of the mountain as woll, and particulary from a spot high up on the

westorn side, abovo the sources of the Mangawhero and Manganui-n-te-ao rivers. —1 am, sir, yours, etc., H. 0. Field. Wangauui, August 19, 18S0.