BOROUGH DRAINAGE.

Franklin Times, Volume 9, Issue 777, 20 October 1922, Page 5

BOROUGH DRAINAGE.

ENGINEER’S REPORT. ON CLEANING PAERATA CREEK. In response to a request by the Borough Council for a report on tne cleaning and straightening of Paerata creek from the proposed drainage outffalf to the Borough boundary, a distance of approximately 60 chains, the Borough consulting engineer, Mr JT. V. Gulliver., submitted his report at* Monday’s meeting of the Council. Dealing with straightening the report states : “I have had a good look at the creek and find) that several diversions have been made already, and think that no further straightening is required on the portion under consideration. From the point of view of sewage disposal it is not desirable that 'the creek should be too straight. The essential thing is to get an intimate mixture of the effluent with the whole of the available water and to allow the mixture to be gently but thoroughly agitated. The creek as it is at present with a slow moving current and sinuous course is most likely to effect this. If the creek were straightened', the increased ' velocity wouldl probably cause <the effluent to form a thread in the swiftest moving part and so would give it little chancy to mix with the remainder of the water. I also believe it desirable that as much purification as possible sroulo take place within the Borough, and too much straightening would reduce the length Off the channel available.” As far as cleaning is concerned the engineer stated : “All growth should be removed from the bottom and sides of the creek and where necessary the banks should be cut down to give everywhere at least 10 feet bottom width. The bottom should be cleaned out* and the sides trimmed and made good. At two of the cuf} offs, the old channel is still open these should be banked off to prevent the effluent stagnating in them. The item of £250 for creek cleaning, shown in my drainage estimate is, I consider, sufficient to do all that is required to put the creek in a fit state to receive the effluent from the filters. The cleaning out and reconditioning of the channel will go a long way towards giving flood water a better get away, and as far as the effluent is concerned, the dilution will be so great in flood time that no harm from this may be anticipated by any flooding of adjacent land. The amount to be spent annually in keeping the creek in oi’der will depend upon the thoroughness of the initial cleaning and would be greatly reduced if the water in Hickey’s dam were .drawn off and the fillies; etc.,i destroyed; also it a fence were’built on each Slide of the creek to prevent cattle from disturbing the banks. The cleaning of the dam should not cost more than £75, and the fencing at ■ 30s per chain would cost £172 10s.” The clerk was instructed to acquaint Mr Svendsen one of the property holders of the estimated cost of cleaning of the creek, while the engineer was instructed to interview the County engineer, Mr J. F McArthur. regarding the cos? <ff cleaning the creek from the Borough boundary to Mm Paerata bridge.