Different types of lakes experience different pressures and responses to surrounding land use, and climate, and may be susceptible to nutrient enrichment as a result. Lowland and coastal lakes are typically saturated in nutrients and susceptible to algae blooms. Whereas high country lakes are typically less enriched. Glacial lakes are typically less nutrient enriched and usually have a low abundance of algae in the water. Glacial lake water clarity is generally poor due to high inputs of glacial flour.
Twenty-five lakes in Canterbury are in "sensitive lake zones", these zones have been identified to ensure nutrient enrichment from nearby land use is managed by setting nutrient limits.
Our Monitoring Programmes
Water quality monitoring is carried out for a range of lakes throughout the region, this range represents different types of lakes with different surrounding land uses. By monitoring this representative range, we gain an idea, overall, of the health of Canterbury’s high country, coastal, lowland, and artificial lakes, including for recreational water quality.
High country lakes are routinely monitored from helicopter at a single site on each lake over five consecutive months (December to May) as part of a cyclic monitoring programme. Larger coastal lakes are monitored at lakeshore or by boat monthly (e.g., Te Roto o Wairewa/Lake Forsyth, Te Waihora/Lake Ellesmere, Wainono Lagoon), and smaller coastal lakes by shore quarterly (e.g., St Annes Lagoon, Lake Rotorua).
Our lake water quality 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.