Te Tai Tokerau Water Trust have completed a 750,000m³ water storage reservoir north-east of Kaikohe. Known as the Matawii Water Storage Reservoir, it will supply water to the recently opened Ngawha Innovation and Enterprise Park, nearby horticulture infrastructure as well as acting as a water source to Kaikohe in times of water shortage or emergency fire-fighting requirements.
Prior to its construction, NZ Environmental Management undertook baseline ecological monitoring and surveying of the stream habitat and a control site as required by the consent. This included;
- Rapid habitat assessment
- Longitudinal profile variability assessment & substrate assessment
- Bank erosion and condition assessment
- Macrophytes
- Macroinvertebrates
- Kāeo monitoring
- Electrofishing and trapping for fish surveys
Following its commissioning, the dam and outflowing waterway (Kopenui Stream) as well as a control site waterway, are monitored regularly for periphyton and water quality. These measurements include dissolved oxygen, temperature, PH and conductivity. Water temperature is also constantly monitored via HOBO Tidbit loggers, although the manufacturer supplied base stations experienced a malfunction and not all data was recorded in the last six months. This has no been adjusted. Optical DO loggers also recorded the dissolved oxygen for a one-month period between January and March.
