NORTH LINWOOD DRAINAGE.

Press, Volume LXIX, Issue 20836, 21 April 1933, Page 9

NORTH LINWOOD DRAINAGE.

REPORT TO BOARD. i CONSIDERATION PROMISED. I A comprehensive report on the storm-water drainage problems of North Linwood was submitted to the Christchurch Drainage Board at its meeting last night by Mr J. Cullens, the engineer to the board. To Mr Cullens had been referred the following alterations suggested by the North Linwood Burgesses' Association:—(a) The diversion of storm-water from the intersection at Linwood avenue and Worcester street from Brittan's drain to Gloucester street storm-water sewer (Porter's drain): (b) diversion of water from portions of Buckley's road now served by Brittan's drain to south Canal reserve drain (Kruse street); (c) Brittan's drain, E branch (McClelland's property); proposed piping of this open drain. Engineer's Report. The engineer's report on these suggestions was as follows: — "(a) In addition to Brittan's drain, the storm-water sewers in Gloucester street and Linwood avenue have to be considered in connexion with any proposal for the abatement of flooding in this district. Investigation has accordingly been made of the City Council storm-water sewers in Gloucester street and in Linwood avenue. The Gloucester street storm-water sewer is of sufficient capacity for the area at present draining into it, except during a big flood in the river at high tide. The discharge is then reduced from 8 cusecs to 63 cusecs. The Linwood f.venue storm-water sewer is not of sufficient capacity apart from the fact that the flow is, at times, impeded by tree roots in the pipes. Some relief is given in the area drained by the latter sewer by means of the storm-water iniets at Worcester street. This relief, however, aggravates the flooding in Brittan's drain. In addition to draining some 19 acres, the Worcester street inlets thus act as a flood relief for part of Linwood avenue. In heavy rain Brittan's drain near Rhona street carries 5-J- cusecs. It is possible, by means of a 15-inch storm-water sewer laid along Rochester' street and into the top end of the Gloucester street stormwater sewer to divert up to 2£cusecs of this flow and so ease to some extent the backing up of the water in Rhona street. This would undoubtedly overload the Gloucester street storm-water sewer in time of flood. The Linwood avenue storm-water sewer, to be adequate for the drainage of the district it serves and also to act as a relief for some of the water from the Gloucester street storm-water sewer area along the north-east side of the avenue, would require to be duplicated with 15in pipes from Gloucester street to Rolleston street, and 18in pipes from Rolleston street to the river. The Gloucester street storm-water sewer is under the control of the City Council. It is constructed of Sft lengths of 24in diameter concrete pipes, butt jointed. It is in fair order, except that from the Surrey street manhole upstream the second and third pipes are flattened at the crown approximately 7in and the fourth and fifth pipes are cracked at the. crown. From the manhole opposite house No. 744 Gloucester street the fourth and fifth and twenty-second pipes are also flattened and cracked at the crown. With reference to trunk stormwater sewers at present maintained by the City Council, it is obviously necessary for the proper drainage of the district, that all such sewers should be maintained and controlled by the board. "Recommendation. Additional storm-water sewers and estimated cost:— . _ "Linwood avenue—lsin and 18in sewer, Gloucester street to river, £1767; Rochester street—lsin sewer, diverting flow from Brittan's dram to Gloucester street, £37o.'' Committee's Recommendation. The Works Committee recommended that the board consider the above proposals as urgent and necessary works when framing the estimates for the current year. . In_ the event of the labour being provided under the No. 5 Unemployment Relief Scheme, the cost would be approximately £llBO for Linwood avenue, and £285 for Rochester strppt The report "was adopted. The engineer also reported that as the land adjoining the South Canal Reserve drain (Kruse street) was subject to flooding it would not be advisable to divert storm water from Buckley's road to this dram. The Works Committee reported that consideration of this matter had been deferred. _ , , As to the piping of the E branch, or Brittan's drain, the engineer reported that this would require six chains and a quarter of 18m pipe, and the estimated cost of materials only, including necessary manholes. was £162. The committee recommended that £BO be placed on the estimates to cover portion of the VV The committee's report was adopted.