Environmental Impacts / Mitigation

As above excepting the visual impact will be lessened as it is not possible to see this position from the access road to Red Hill.

10) Power House & 11) Spillway

The proposal is for this to be located at GR 818.0 512.0 on the TLHS bank of the Parapara River on the flood plain delta of the Glen Gyle.
(See also Plate 4 for the location.)
The 8m x 6m x 3.6m high concrete building housing the turbines and generator will be sited in a clearing of the regenerating bush in this location avoiding the larger remnant hard beech trees on the bank. Concrete is the preferred material for possible fire resistance with the minimum clearance to existing vegetation and to contain any noise from the generator equipment. Suitable plaster and colour treatment will be provided to the exterior of the building so as to blend in to the surrounds.

A security fenced cage will house the transformer and switching equipment and include a pole to support the overhead transmission lines towards Glen Mutchin and ultimately into Washbourne Creek and connection to the existing grid. The cleared area will be limited to the area of the building and fenced area plus four metres. The access road will terminate outside the building at a vehicle parking area of approximately 50m2, which will be the work area for construction of both the powerhouse and the spillway.

The spillway will involve the excavation of material from the river bank which comprises boulders of up to 1.2 metres in diameter and this indicates considerable stability exists in the bank at this point. The draft tube from the turbines is expected to exit via the spillway into the river at an oblique angle of 45 degrees to the downstream flow via a concrete wing wall structure and pad at river bed level.

An approved composting toilet will be provided for construction and for the later use of maintenance personnel and the pubic.

Environmental Impacts / Mitigation

Impacts are expected from both the construction and operation phases. These include:

1. Vegetation clearing.
   
2. Visual.
   
3. Noise
   
4. Bank stability
   

In addition, the construction phase will include the possible impacts of spillage of fuels or oils or concrete materials into the river itself.