WAYWARD RIVERS.

Dominion, Volume 1, Issue 275, 13 August 1908, Page 3

WAYWARD RIVERS.

| ! THEIR CONTROL IN WAIRARAPA. i AN UNMASTERED ENGINEERING ■ I . . PROBLEM., Tho various local bodies, river boards, and farmers generally continuo to ■ have a great deal of trqublo in tho task of river protection in tho Wairarapa (writes our correspondent). Owing to tho fact that the sources of the rivers in tho Tararua Mountains aro so closo to the valley over which they run, the streams in their sudden swiftness ravage, the ravines and tho uplands, and spread tho. soil upon their beds leading over tho plains., Tho result is : a' continual silting up of tho river beds, and this- again leads to . tho streams cutting out new channels to the despair of nearly'every engineer who. has tackled tho difficulty. It has been decided,by. some people, on the evidence of the stony ■ plains in various portions of the .Wairarapa, that thq locality was once a lake;' but there ,is equal reason to believe that those stony areas were caused by the vagaries of the rivers, which silted up, and then, roaming at will unrestrained by the ingenuity of man, cut for themselves new courses in order to find a level.

' In the last twenty years the Ruamalianga has stolen hundreds and hundreds of acres of land, but the smaller streams, such as the Waiohino, between Carterton and Greytown, and tho Waingawa, between Cartorton and Masterton, appear to wage a more relentless war 1 with the land, and only the aid of engineering skill in tho shape of groynes, fas-' cines, and willow planting -has kept them from wrecking the country far and wide. Some time ago the Waingawa threatened to return to a very old course on the . Masterton side of tho bank—a result which would have necessitated . lengthening the bridge on the main road between Carterton and Masterton by another fifty yards. Tho Wairarapa and Masterton County: Councils constructed groynes and a stone bank at great expense,, and tried to run a new channel down tho contro of the. river. At the end. of a year's . time, tile groynes had served their purpose in reclaiming the laud; but then the river made a dash for .the low-lying northern bank, and now threatens to waste hundreds , of acres. Tho ;county councils interested aro consequently ploughing and scooping up tho centre.of the river-bed in the hope that they will keep the stream within proper limits. At present.it seems as if tho effort will bo successful, but the .Waingawa is a snow river; at times it rises suddenly four or five feet in a few minutes, 1 and it will always require constant watching;. Tho gorso which grows .in the bed of this and other rivers is another continuous,danger which tends to . divert the streams from their ordinary channels. Tho.troublp with tho Waioliino Ilivcr between Carterton and Greytown has been tensified by tho' Maiingatariri Stream ' being .choked at'its mouth, where it joins the.Waiohine. The main cause of this is said to be a groyne constructed- on the opposite bank of tho Waiohino-somo ten years ago., Tho result,. however, is that when there is an. extra rainfall, tho Maungatariri overflows. its banks and floods the country for miles, to the general detriment-of tho farmers. The overflow once or twico'in the/year would riot do much damage, but probable.good in,enriching tho/land,. but the .visitation's of .this description are much . too frequent, ..and tjio, result is that acres, of land are .being spoiled, , farms' are mutilated, arid : the farmers, are harassed with much loss. Tho whole question of river'protection is a problem which so.far. has not yet been successfully mastered by the 'best engineering minds in" the Dominion. "