Our Living Land
Land Management
From geology and vegetation to land use and the meandering paths of our waterways, Te Hoiere catchment has evolved over time. Today, Te Hoiere Project seeks to understand the relationships that shape these changes, now and into the future, by bringing together science, mātauranga Māori, and local knowledge.
Each of the catchment actions in Te Hoiere Project are led by a project partner, the community or both. The land management objectives of the Project are complex, with the Environmental Science Team at Marlborough District Council leading much of this work alongside the community, external science providers, and other project partners.
The Project’s Integrated Catchment Enhancement Plan, developed in 2020-21 through a process of ‘planning by the community for the community’, identifies a need to better understand the catchment and land management actions relating to sediment and erosion. In turn these actions would lead to improvements in natural ecosystems while lifting economic and community well-being.
In response, work is being carried out to:
- Assess river geomorphology and dynamics to increase knowledge of the physical landforms and processes to support decision-making (Complete)
- Map erosion vulnerability within the catchment (Underway)
- Develop a riverbank erosion plan, collaboratively identifying ‘hotspots (Underway)
This work supports the community aspiration that landscapes are preserved, with pristine and rugged upper catchments as well as rural catchments with a patchwork of protected areas and productive land. The result is a diversity of landscapes, while the community enjoys a flourishing natural environment.
The Project’s land management research and planning actions help with everyone’s understanding of the catchment’s land processes in a way that’s collaborative and practical. The scientists partner with the community, external researchers and experts on these larger research studies, such as Auckland University.
River Geomorphology
Geomorphology is the study of landforms and how they have evolved over time. Te Hoiere Project has funding to assess river geomorphology in the catchment to better understand how river landforms relate to erosion and, in turn, how that may impact land management choices.
A foundational study into Te Hoiere River geomorphology was authored by Dr Jon Tunicliffe from Auckland University, published in 2021 by Department of Conservation. This report of three rivers, including Te Hoiere, looked at geomorphology to demonstrate how knowledge of their physical landforms and processes can support decision-making for river restoration. Read the report on the Department of Conservation website by clicking here.
Building on this work, Council scientists worked with Dr Tunnicliffe to carry out detailed geospatial mapping for Te Hoiere/Pelorus, Rai, Ronga, Opouri, Tunakino, Whakamarino (Wakamarina) and Kaituna Rivers.
This mapping and modelling by University of Auckland can be found at the link below.
Te Hoiere River Dynamics: River processes and typology in the Te Hoiere and Rai catchments
Geospatial Tools
Funded through Te Hoiere Project and partners, the development of geospatial tools for the catchment is to improve catchment understanding. The work relies heavily on 2020 LiDAR data to provide a fine-scale image of the land surface. These tools can be used to inform sediment mitigation and riverbank erosion plans, as well as provide landowners guidance to aid on-farm decision-making.
Erosion Vulnerability Mapping
This geospatial tool addresses the Project's goals to better understand the catchment by establishing a way to assess erosion vulnerability. Eventually, this feeds into the project's land management objective that a community-led riverbank erosion plan is developed and available for the community to inform individual landowner actions, such as resource consents.
Conceptually, this mapping work combines different datasets from above and below the ground, as well as historic information to better understand the likelihood and influences of erosion in this catchment. The datasets provide a reliable identification of land that may be more at risk of erosion, which would enable land managers to make better decisions.
Below, streambank erosion in Rai Valley – August 2023; Photo/Marlborough District Council
Riverbank Erosion Plan
Following on from the river geomorphology work, the Project is now focussed on practical application of this research, with work underway to develop a catchment-wide plan for riverbank erosion. This community-led plan would provide information for individual landowners and land managers to guide decisions that impact erosion management. In the future, this will involve community engagement to help form this plan, as well as input from an external expert in river and erosion engineering to guide feasibility.
Project Partners
Scientists with Marlborough District Council lead this project alongside the community, with support of Council’s GIS team, Te Papa Atawhai Department of Conservation, and Ministry for the Environment.
In addition to the ongoing support of the Project partners listed above, various experts and agencies have been consulted to help with undertaking of this work. These include Our Land and Water, University of Auckland and Biospatial Ltd.
Related Land Management
Forestry
Our Project partners at the Top of the South Wood Council are leading five projects as part of Te Hoiere Project that focus on land management.
Click here to learn more about forestry.
Nature Based Solutions
Marlborough District Council is participating in a national-level science project seeking to inform nature-based solutions for river management. All councils across the country are participating in this work, which is coordinated by the Ministry for the Environment. Te Hoiere catchment was chosen to enable further science modelling and scenarios for better catchment understanding.
A feasibility study to explore nature-based solutions in the catchment will undertake modelling, based on a series of actual rainfall events and projected climate change scenarios. The aim of the work is to understand if it is possible to reduce storm peak flows in the rivers, across the catchment and with the work of the community. Community meetings began in late 2023 and are ongoing, with this research expected to conclude in April 2025.
The Nature Based Solutions approach has been adopted in large scale in Europe and America but is less well understood in a New Zealand context. The national-scale of the project is seeking to rapidly improve our understanding of this approach in New Zealand catchments and farming systems.
Read more about this research and its aims on the Marlborough District Council site.
Land Use Modelling
Our Land and Water is funding Synthesis Scenarios for Future Land Use, undertaken by Manaaki Whenua Landcare Research and Perrin Ag. This project looks to scenario modelling to show how a water quality target can be met in three catchments by changing land use. These scenarios will not compromise profitability, increase greenhouse gas emissions, or result in other environmental impacts. The three catchments are Waihao (Canterbury), Tukituki (Hawke’s Bay) and Rai Valley (Marlborough). These catchments have community-defined water quality objectives that are unlikely to be achieved through reasonable mitigation efforts alone.
