Waikato Regional Council monitors groundwater quality at sites throughout the region. Measures of water quality include nitrate, pesticides, bacteria (an indicator of disease-causing micro-organisms) and iron.
Threats to our groundwater quality come from many sources and are referred to as either point (from specific locations) or non-point sources (from wider areas).
Point sources include:
Non-point sources include:
Waikato Regional Council monitors the state of groundwater quality in the Waikato Region for:
Waikato Regional Council also gets groundwater information from:
The table below lists the different contaminants we measure to determine groundwater quality in our Region and their maximum acceptable values (MAVs) for drinking water.
|Contaminant||Drinking water MAV standard1||Principal concerns|
(11.3 g/m3 as nitrate–N)
Nutrient enrichment of rivers and lakes
|Arsenic||0.01 mg/l||Human and animal health|
|Boron||1.4 mg/l||Human and plant health|
(indicators of disease–causing micro–organisms)
|Less than 1 in 100ml of sample||Human health|
|Pesticides||Chemical specific||Human and animal health|
|Hydrocarbons||Various||Human health and ecology|
|Synthetic organic chemicals||Chemical specific||Human health and ecology|
|Heavy metals||Metal specific||Human health and ecology|
The most common chemical contaminants found in community water supplies with near or above the maximum acceptable values for drinking water are:
It’s natural to find high levels of arsenic and boron in geothermal areas (mainly Taupo), but nitrate contamination is the result of the way we use the land.
Check out our indicators of groundwater water quality and groundwater well construction.
Find out how to protect community sources of groundwater.
Check out the national drinking water standards on the Ministry of Health(external link) website (online publications).