MANAGEMENT PLAN

Kaiwharawhara and Korimako Streams Policy

The streams are acknowledged as being a particular focus of both the park and the gorge ecologically and in landscape terms. Issues which require attention include water quality, protection and enhancement of stream habitat for native species and trout , riparian vegetation, bank erosion and the removal of storm and construction debris from the streams and adjacent bank areas.

The quality of the water in the stream where it flows through the park is reasonable. Monitoring is carried out at the Hutt Road and the Wellington Regional Council monitors water quality downstream of the park. Water quality is also monitored upstream in the Otari Native Botanic Garden and in Cummings Park. The main sewer line located along the route of the Kaiwharawhara Stream was recently upgraded resulting in improved water quali ty and the leachate from the old Curtis Street landfall which was polluting the stream has been diverted to the sewer. The quality of the water in the Korimako Stream is marginally outside the water classification standards. However, by the time the flow reaches Trelissick Park the quality has improved due to the dilution provided by additional incom ing flow.

Following the 1976 storm a stream bed material trap was constructed on the Kaiwharawhara Stream at the eastern end of the park. This has resulted in modifications to the stream channel and bed upstream of the structure.

The Wellington Regional Council is the regulatory authority for water quality and stream control including riparian management. It administers resource consents for use of water, discharges into water and works affecting the bed of water bodies. It works closely with the Council's Drainage Department, which manages the city's stormwater ander systems, on water quality an d stream management in the Kaiwharawhara Stream catchment.

Policies:

The remedial works outlined in the Kaiwharawhara and Korimako Streams Management Report (G & E Williams Consultants 199 2) form the on- going basis for stream management.
The need for the bed material trap in the park will be reviewed from time to time as ongoing upstream bank stabilisation wo rks are carried out.
Stream stabilisation works shall be carried out in a manner that minimises adverse visual impacts and that enhances the opp ortunity for habitat creation and the establishment of appropriate riparian vegetation.
Landscape and habitat values shall as far as possible be protected during stabilisation, rehabilitation and stream manageme nt works.
All stream stabilisation works shall as far as possible utilise natural materials.
All willows shall be removed from the park with the initial emphasis being on the area below the confluence with the Korima ko Stream.
There may be exception in the case of willows at the northern end of the park as noted in the Draft Development Plan, parti cularly in relation to Wightwick's Field.
Encouragement shall be given to investigations which are aimed at reducing stormwater contamination and rubbish entering th e Kaiwharawhara and Korimako Streams.
To liaise with Wellington Regional Council and Drainage Department, Cityworks Division, on matters of stream control and wa ter quality affecting the Park.