Canterbury/Waitaha has many different types of rivers, from alpine and braided rivers to hill-fed lowland streams. Braided river ecosystems form a large part of the Canterbury landscape and are internationally rare. Along the coastal plains, groundwater emerges to create spring-fed streams which meander seaward. The water quality of rivers in Canterbury is strongly influenced by land use – from mountains to sea.
Results are reported on LAWA for Environment Canterbury’s river monitoring network of several hundred sites across the region.
The rivers of Waitaha support a diverse range of plants, insects, fish, and birds, provide for cultural and recreational values, and hydroelectric power generation.
River systems are vulnerable to land use effects, including from nutrients and sediments from land, water takes for irrigation and hydro schemes, invasive plants and animals, and pollution. Increased nutrients enable more algae and aquatic plants to grow excessively. Too much algae and plant growth makes for unsuitable habitat for insects, that aquatic animals eat. The more modified the landscape, generally, the poorer the river water quality.
Our Monitoring Programmes
Water quality monitoring is carried out for a range of rivers and streams throughout the region. By monitoring this representative range, we gain an idea, overall, of the health of Canterbury’s rivers, including for recreational water quality.
Sites monitored for state of the environment reporting are sampled monthly. Sites monitored for compliance with our regional plan are generally sampled quarterly. Sites for recreational water quality are sampled weekly from November to March.
Water quality data inform what condition rivers are in, and if water quality is getting better or worse. Our data help us assess and report on the state of Canterbury’s water resources, including for recreation, to evaluate our resource management plans, and to explore emerging issues related to sustainable freshwater management.
Regional Plans and Restoration Activities
Increased demand for freshwater in Canterbury means that freshwater resources need careful monitoring and measurement to achieve effective and sustainable water allocation and management. Our focus, through our regional resource management plans and activities (including under national policy statements, standards, and regulations) is on sustainable water and land management. Environment Canterbury works in partnership with Ngāi Tahu, and with territorial authorities, in carrying out its freshwater management functions with water users and local communities.