Subdividers’ plan for sewage plant

Press, Volume CXI, Issue 32640, 23 June 1971, Page 20

Subdividers’ plan for sewage plant

The possibility of a Worsleys Spur subdivider installing and financing a temporary, packaged treatment plant for sewage, the Christchurch Drainage Board to operate and maintain it until such time as it could provide its own, permanent sewerage service to the area, was discussed by the board last evening. It is expected that the board will not be in a position to provide permanent service to the area for about 10 years.

The subdivision plans on behalf of the Francis Estate, envisage 300 sections to house 1000 to 1200 persons by 1980 —with a start being made in 1975—0 n the spur above Halswell. The board was informed of other proposed sub divisions in the area and other possible private treatment plants. It said such treatment plants, provided they met standards and conditions laid down,. were possible under the board’s policy. Steven and Fitzmaurice, consulting engineers, sought the board’s views on the possibility of providing temporary sewerage disposal for the subdivision by means of a package treatment plant,

5 the disposal of treated efflu- . ent to be on the' property ? owned by the Francis Estate ' or into the Cashmere Stream. ) This would enable the sub--1 division to be started in 1975, r some 50 sections to become J available yearly after that ' date. The suggestion of a package treatment plant was , based on the belief that the 1 board would not be able to ‘ offer sewerage service for the r area, including Happy Home ‘ Road, for at least 10 years. t The engineer consultants j said that the suggestion of r an extended aeration type package treatment plant might offer an economical t solution to the problem posed »by existing homes in the . Happy Home Road area (the r board is currently considerf ing a petition seeking sewers , for those homes) and for

future urban development in the general area.

AUCKLAND PLANTS

The consultants referred to the success of package treatment plants in the Auckland region and in the Hutt, and said that disposal of wastes from the Worsleys Spur area could be effected in a manner which would in no way affect the characteristics of the area and asked:

"Does the board accept that it is possible to provide sewerage service to this area until the board’s service is available? Would the board accept the task of operating and maintaining a plant in the area, and would the board support the proposal in any subsequent application to the Paparua County Council and the Regional Water Board?”

The chief engineer (Mr P. J. McWilliam) said that the zoning of the area was complicated by Halswell merging with Paparua. The board had informed Paparua that it would endeavour to sewer the Worsleys Spur area and Halswell township by 1980.

“It is considered that a good case could be made for discharging treated effluent from this number of people to the Cashmere Stream or Heathcote River. However, the matter would no doubt have to be considered in the light of what other discharges would have to be accommodated until a sewer outfall was available. OTHER DEVELOPERS

“It is known that other developers are interested and further treatment plants have been and will be proposed," Mr McWilliam reported. He said that incorporating the Happy Home Road houses in any such proposed private treatment scheme would mean a wait of three or four years for house owners there now, and it would be very uncertain if there would be savings in costs.

Mr McWilliam said that the board in 1960 had laid down a policy on temporary treatment plants which said that provided necessary approvals were given the board would not oppose' them, and would operate and maintain plants while they were needed.

“No doubt the board would still accept this general approach, but in view of the changed situation today should review and update this policy. The extended aeration type of plant frequently does not produce an effluent with the standards recommended by the Royal Commission, which could well be the standards required in this case.” WATER RIGHT The board said that an approved temporary treatment plant, not necessarily of the type suggested, could be approved. It was reluctant to consider any temporary measure until it had established at least one viable way of establishing its now outfall for the area. A report on that aspect would be considered by the board soon.

If the board was satisfied with the type of treatment plant to be provided, it would operate and maintain it subject to conditions. The board would not support any application for a water right It would almost certainly lodge a pro forma objection in order to suggest possible effluent standards. However, the board would not oppose such applications in other respects once it had established it had a reasonable method of providing a permanent sewer outfall for the area.

The board also resolved to consider its policy regarding temporary treatment at an early date, and authorised two staff metpbers to inspect package treatment plants in the North Island.

The chairman (Mr A. J. McTainsh) said it was essential that the board’s staff knew of recent developments in New Zealand in different types of treatment plants.