MONITORING AND REPORTING: Waikato Regional Council regularly monitors and reports on our region's lake and wetland resources and the pressure they face.
The Waikato region has more than 100 lakes, ranging from small ponds to the largest lake in New Zealand, Lake Taupo. Waikato Regional Council is looking at ways to protect Waikato’s lakes and restore those with poor water quality.
Demand for farmland and urban development close to water has meant that most of our lakes are now much smaller and shallower than they were in the early 1900s. Some lakes have been completely drained and turned into pasture.
Lakes tend to collect pollutants over time because their waters are still, unlike rivers where moving waters carry pollutants away. More intensive use of land in lake catchments means many lakes now receive more nutrient and sediment loads than in the past. Nutrients encourage nuisance plant growth, such as water weeds and algal scums.
Waikato Regional Council monitors the water quality of lakes using four main trophic indicators:
The five trophic states determined by these indicators are:
Waikato Regional Council's land and river-based works and services are designed to protect the lake water quality and the land surrounding them from the effects of erosion. The work done includes:
Waikato Regional Council also works with community groups and other management agencies to set water levels for peat lakes to help protect these unique ecosystems for the future. Peat lake ecosystems are easily damaged by over drainage of neighbouring land.
There are now community caregroups looking after several of our peat and lower Waikato River lakes in the Waikato region. Lake Ngaroto is also the focus of a major rehabilitation project.