The water quality of lakes in Canterbury is strongly influenced by their locality and associated land use types. For example, lowland and coastal lakes are typically saturated in nutrients, and predominately in a phytoplankton dominated state. Whereas, the high country lakes are typically less enriched. Glacial lakes are of low nutrient and algal biomass state, however the water clarity is generally poor due to high inputs of glacial flour. Other high country lakes are at risk of nutrient enrichment from increasing land use pressures, and nutrient management is essential for keeping these lakes clear and free of increasing algal biomass.
25 lakes in Canterbury are located in what have been deemed to be "sensitive lake zones". These area's have been identified to ensure nutrient enrichment from nearby land use is managed, by setting nutrient limits within these zones. A number of nutrient limit setting processes are currently underway in Canterbury.