MANDEVILLE AND RANGIORA DRAINAGE.

Globe, Volume XXII, Issue 2133, 24 December 1880, Page 4

MANDEVILLE AND RANGIORA DRAINAGE.

The report of the Commissioners has been completed. Messrs Marshman, Bell, and 3jowe were asked to report on the best outlet and take evidence as to the original overflow of the drainage, to enquire as to the effect of the works done, end the expediency of those contemplated by the Board, and generally to report as to the most efficient system of drainage for the district. They report principally in favor of tha lines of action followed by the Board, and add in their concluding remarks the following recommendations : That the embankments across the Oust floodway and eastern side of cross drains generally, should not be raised, and that for the present, and until the capacity of the mam drain shall have been increased, Ho. X drain should not be enlarged, nor anything done that would 4end into main drain more water than now goes'into it. As far as might be possible the shingle banks in the lower parts of the drain should be immediately cleared away. The operations of the Board ought to be directed primarily to keeping the bed of tho drain clear, and concurrently, as funds admit, to the reduction of the bed to the gradient shown in plan attached. _ As the Board can afford it the drain should be widened, the material taken out to be used in etrengthening the banks. They think that Government should be requested to cause the railway bridge over Eyroton branch line to be lengthened to clear the drain ; also, that a catch drain be out on south side of main drain, and possibly on the north side, discharging into the Waimakariri, near the mouth of the Ohoka stream, to take storm water from lands that are too low to aimit of being drained into the main drain. The Commissioners thought that, if possible, Daokey Creek might be diverted into Southbrook, on sub-creek running through sections 5543 and 5535, and the creek near Bennett’s railway station, recently diverted into the watershed of the Oust, be diverted back again by its original course to within the watershed of tho Byre. The quantity of material to be shifted in the enlargement of the main drain would be 246,000 oubio yards, and it would then discharge 166,000 feet per minute, equal to nearly two inches of rainfall over the Oust watershed in twenty-four hours. When this enlargement had been made, and it was shown that the drain can be permanently maintained at these dimensions, Ho. 1 drain might be enlarged. The Board might find it necessary, owing to limited funds, to'spread operations over a considerable time, but if the works were done in the order and on the lines given every step wonld be contributing to the general effect. If the operations are accelerated the dwellers on the line of drain will receive within a shorter time, or if retarded they will be longer without, the relief they desire to obtain.