Development for south-west

Press, Volume CXII, Issue 32848, 23 February 1972, Page 18

Development for south-west

The Christchurch Drainage Board last evening gave a higher priority to its No. 11 catchment system, which will take in Halswell, as well as the present area, additional areas of 200 acres between Cashmere and Bowenvale, 140 acres of the Sparks RoadHendersons Road area, 1000 acres of the Worsleys Spur-Happy Home Road area and 270 acres in Halswell.

It also agreed that consideration be given to the early provision—the works committee suggested three years—of work that will allow the staged development of the areas at Halswell and Happy Home Road. A programme of improvements spread over more than 15 years was given by the chief engineer (Mr P. J. McWilliam), with the total cost estimated at sl.4m on present-day costs.

“Further subdivision will almost certainly take place and the availability of sewer outfall will be of considerable financial advantage to the subdividing owners,” the works committee said. “With this in mind, the committee has asked the board's solicitors to look into the question of the board being able to make a ‘headworks ’ charge from those subdividers of land who would benefit from proposed expenditure by the board.”

Mr McWilliam said that a consultants’ report in 1969, indicated that there were deficiencies in the main trunk

sewer system and that there was virtually no capacity available for extensions of the urban area without the construction of more trunk sewers.

One area of deficiency was the system of sewers and pumping stations serving the south-western part of the urban area—the No. 11 catchment system. It had been known for some time that parts of the system were inadequate. This was shown by sewer gorging

and overflows to the Heathcote River at times of peak flow. Thus, it was evident that some work would be required to improve the system to handle the present development without considering Halswell and areas of possible future development. Mr McWilliam looked at five schemes. The one adopted by the board will require 29,770 ft of gravity sewers ranging in diameter from 6in to 30in, 19,850 ft of rising main duplications or

enlargements, upgrading of seven pumping stations and diversion of three pumping station discharge points. Mr J. F. Davidson said it might be wise to consider installing a treatment plant in the south-west area.