CPWL works closely with our shareholders, stakeholders and regulators to promote and deliver initiatives that enhance environmental outcomes and reduce environmental impacts of the scheme.
CPWL has established an Environmental Management Fund (EMF) for the enhancement of biodiversity across the catchment. The fully operational Scheme generates approximately $115,000 annually for allocation by the EMF. Applications for funding are considered by a Committee appointed by CPWL. Applications are considered for projects designed to address adverse environmental impacts associated with the Scheme, or for biodiversity enhancement projects in the Selwyn / Te Waihora.
The following projects will be considered by the EMF:
Funds have been provided for the planting of native species, the development of wetlands, and for research.
CPWL shareholders are required to apply the use of good management practices and CPWL assists with this through the following initiatives:
The CPWL scheme is part of the Selwyn Waihora Catchment. The Selwyn Waihora Catchment is considered "Overallocated" by Environment Canterbury (ECan). CPWL Shareholders hold groundwater consents for the abstraction of over 200 million m3.of groundwater per annum.
This volume of water exceeds available groundwater quantities, and continued abstraction will deplete the groundwater resource, reduce flows in lowland streams and hill-fed rivers and adversely affect ecological and cultural values.
Prior to the CPWL scheme delivering water to its Shareholders, approximately 100 million m3 was abstracted per annum. With CPWL now fully operational this annual abstraction has reduced to 32 million m3 as groundwater users switch to the CPWL supplied surface water.
This represents a 66% reduction in the abstraction of groundwater since the commencement of CPWL water delivery.
In addition to the CPWL EMF, funds are made available to Te Rūnanga o Ngāi Tahu for environmental initiatives associated with the restoration of health / mauri of the environment in the vicinity of Te Waihora / Lake Ellesmere.
Funding is also provided for the periodic opening of Te Waihora / Lake Ellesmere to the sea to permit the flushing of water from the Lake to the sea.
More detail on the Te Waihora / Lake Ellesmere opening process can be found on the Environment Canterbury website.
CPWL and Aqualinc have developed a website that permits shareholders to access the daily reference evapotranspiration (ET) for the scheme area. Shareholders can view the ET for the last ten days and the forecast for the next three days.
Potential Evapotranspiration is one of the key pieces of information used to make an informed decision on whether to irrigate the next day.
"Meeting a Sustainable Future Selwyn and Hinds"
DairyNZ is working one-on-one with a group of farmers and their advisors to support and explore the options for reducing their farm environmental footprint, while maintaining profitability and considering the strategic objectives of their business. This includes achieving nitrogen reductions and reducing Green House Gas emissions. The objective of the programme is to:
>If you are a farmer in the Selwyn Waihora area and are interested in becoming one of the supported farms or being engaged with a range of extension activities, please contact the CPWL Environmental Team for more information.
The Selwyn Near River Recharge project includes the construction of an off-take on the Central Plains Water scheme that supplies up to 3.5m3/s of Rakaia River Water into a leaky basin beside the upper Selwyn River / Waikirikiri during dry periods.
River water discharged percolates through the groundwater system beneath recharging the aquifer, feeding springs that are the source of streams where mudfish live, and supporting flows in the interconnected Hororata, Irwell / Waiwhio and lower Selwyn / Waikirikiri rivers. It is not expected to increase the length of time the Selwyn River / Waikirikiri flows under the SH1 bridge.
Water is only discharged when forecasting indicates that the area is going into a dry period, with water discharged to keep the flows downstream the same as they would be in an average year. If it is predicted to be an average or wet year, then water is not discharged. This means in some years the system will not be used at all. The aim of the project is to:
The basin is located on the upper Selwyn River in the middle of a pine plantation. The system only operates when the nearby Selwyn River / Waikirikiri is not flowing naturally and does not mix at the surface with natural river water. It primarily operates during winter to compensate for dry winters that result in low river flows the following summer. Monitoring of this project completed in May 2020 will be carried out to understand the impact of the Recharge project.
CPWL has completed planting at the Sheffield intake, planting 2,100 trees at the Sheffield Pond, and riparian plantings at the Hororata River Crossing.
Further initiatives include: