Horowhenua (Waiopehu) Water Quality Interventions

This page covers work by Horizons Regional Council and partners to improve water quality and aquatic health for the Waiopehu Freshwater Management Unit (FMU). You can learn more about the Waiopehu FMU and the pressures impacting its freshwater environments here. 
The National Policy Statement for Freshwater Management (NPS-FM) directs regional councils to identify areas called Freshwater Management Units (FMUs). FMUs are becoming a key spatial units for freshwater management in the region. More information about FMUs can be found via Oranga Wai | Our Freshwater Future.  

What we’re doing to help the Horowhenua (Waiopehu) FMU

Learn about the Arawhata Constructed Wetland Complex

The Horowhenua (Waiopehu) Water Quality Interventions are designed to improve the health and wellbeing of waterbodies in the area. The project also aims to further characterise the surface and groundwater of the FMU to improve understanding of the flow paths to Punahau Lake Horowhenua, connections between catchments within the FMU and the state of the Ōhau and Waikawa estuaries. 

A Governance Group for the intervention work has been established, which includes Horizons Regional Council, Horowhenua District Council, Muaūpoko Tribal Authority, Te Rūnanga o Raukawa, Lake Horowhenua Trust, and Ministry for the Environment representation. 

This work leads on from the Lake Horowhenua Accord established in 2013, where five parties representing Muaūpoko owners, community interests and statutory bodies agreed to work together to provide leadership and halt degradation of Punahau and Hōkio Stream.  

One of the key interventions is the construction of a wetland complex in the Arawhata sub-catchment of Punahau. The wetland complex will be constructed to improve the quality of water which flows into the lake. It will also consider economic, social and recreational opportunities in future development. Horizons has purchased a 142ha dairy farm in the Arawhata sub-catchment for this purpose. 

Other initiatives, both past and ongoing, include investments in sediment traps, lake weed harvesting, fish passage around the lake weir, riparian fencing and planting, working with horticultural growers in the Horowhenua District to maximise nutrient use and reduce leaching to waterways, and developing sediment and erosion control plans for horticultural growers. 

The video below, featuring representatives from the Lake Horowhenua Trust and Horizons Regional Council, explains how the weed harvesting fits into the suite of initiatives. 

Find out more about the Horowhenua (Waiopehu) FMU

Learn about the Arawhata constructed wetland complex or dig deeper in to the current state of the Horowhenua (Waiopehu) FMU. Here's where you'll also find relevant reports and other documention, including meeting minutes with various stakeholders.