Open channel through Halswell to Avon-Heathcote Estuary

Year proposed

  1875

Status

  Not implemented

Location description

  Northern Lake Ellesmere up through to the Halswell River. Bray (1875) Scheme No. 1 (see designs/drawings figure).

Description of option

  A 15 mile (24.1 km) open channel cut was proposed from the north of Lake Ellesmere up through to the Halswell River - effectively reversing it.

Opening, closing, and lake level control description

  Allows continuous discharge.  Requires a higher lake level to obtain suitable hydraulic gradient.

Maximum discharge

  below 50 cumecs

Maintenance/Management description

 

Cost description

  Cost for 15 miles of cutting: 1,245,600 pounds (Bray, 1875).

Fish passage benefit rating

  Low

Potential running impacts or benefits

  The fall required over 24.1 km cut is far too great to prevent a rising of the lake level during a flood, even with the greater head available in 1875. Scheme more "one for preventing the drainage of the lake" (Bray, 1875).