Freshwater Data

"A unit of rock or sediment is called an aquifer when it can yield a usable quantity of water.
Aquifers may occur at different depths in the same location. The map shows the areas of New Zealand’s land surface above one or more aquifers. The aquifer boundaries were described by White (2001), and some boundaries were updated by Moreau and Bekele (2015), using information provided by regional councils and from Lovett and Cameron (2015). The map has 153 polygons (aquifer outlines), some of which have more than one aquifer.
Methods for defining aquifer boundaries generally rely on knowing the locations and characteristics of productive wells, and using geological maps to identify water–bearing materials. In many cases, these boundaries are also influenced by management attributes such as regional or property boundaries, and surface water catchments (Lovett & Cameron, 2015).
This dataset relates to the ""Location and area of New Zealand’s aquifers"" measure on the Environmental Indicators, Te taiao Aotearoa website.
"

River flow is the quantity of water passing a point over a certain time. Each river or stream has its own natural flow characteristics, such as peak flows following rain or high spring flows from snow melt. Overall, this affects how much water is available for irrigation, drinking water, hydroelectricity generation, and recreational activities. River flows also influence a waterway’s physical form, habitat, and ecological processes like migration, spawning, and food supply for aquatic life.

This dataset relates to the "The geographic pattern of river flows" measure on the Environmental Indicators, Te taiao Aotearoa website.

River water quality water is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much can lead to ‘nuisance’ growths of river algae and aquatic plants, degrading habitat. High concentrations in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains raw data collected at NIWA monitored sites of the National River Water Quality Network (NRWQN) over the period 1989-2013. The NRWQN network is used to calculate national trends in river water quality. Fields are described as follows. Refer to Larned et al. 2015 for further details:
sID ---- Unique site ID
srcid ---- Region site is located in
sflag ---- River (r) or Estuary (e)
river ---- River name
location ---- Name of site
nzmge ---- easting
nzmgn ---- northing
NZReach ---- REC1 segment identifier
sDate ---- sample date
Q ---- Recorded flow when sample was taken, cumecs
npid ---- NIWA parameter ID (as used in Larned et al. 2015)
values ---- Parameter value (units are mg/m3, except CLAR (m) and ECOLI (n/100 mL))

For more information please see:
Larned, S, Snelder, T, Unwin, M, McBride, G, Verburg, P, McMillan, H (2015).Analysis of Water Quality in New Zealand lakes and Rivers: data sources, data sets, assumptions, limitations, methods and results. NIWA Client Report no. CHC2015-033. Available at data.mfe.govt.nz/x/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "River water quality" measures on the Environmental Indicators, Te taiao Aotearoa website.

River water quality water is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to ‘nuisance’ growths of river algae and aquatic plants, degrading habitat. High concentrations in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams.

Trend statistics and calculation results for the periods 1989-2013, 1994-2013, and 2004-2013 are provided by monitored site. Units for parameters are mg/m3, except CLAR (m). Refer to Larned at al. 2015 for further details.

For more information please see:
Larned, S, Snelder, T, Unwin, M, McBride, G, Verburg, P, McMillan, H (2015).Analysis of Water Quality in New Zealand lakes and Rivers: data sources, data sets, assumptions, limitations, methods and results. NIWA Client Report no. CHC2015-033. Available at data.mfe.govt.nz/x/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "River water quality" measures on the Environmental Indicators, Te taiao Aotearoa website.

Nitrogen is an essential nutrient for plant growth. It occurs naturally in the environment but is added in agricultural processes (typically as fertiliser) to boost production. Although much of the applied nitrogen is taken up by plants, livestock waste returns a considerable amount to the soil. Nitrate formed from this waste easily drains (leaches) from the soil before plants can absorb it, and it can enter waterways, potentially harming ecosystems.

This dataset relates to the "Trends in nitrogen leaching from agricultural activities" measure on the Environmental Indicators, Te taiao Aotearoa website.

River water quality water is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to ‘nuisance’ growths of river algae and aquatic plants, degrading habitat. High concentrations in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli bacteria can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.
State (percentile) results for the following parameters, by monitored site for the period 2009–2013, are provided. Refer to Larned at al (2015) for further details.

 Clarity (CLAR), m
 Ammoniacal nitrogen (NH4N), mg/m3
 Nitrate nitrogen (NO3N), mg/m3
 Total nitrogen (unfiltered) (TN), mg/m3
 Dissolved reactive phosphorus (DRP), mg/m3
 Total phosphorus (unfiltered) (TP), mg/m3
 Escherichia coli (ECOLI), n/100 mL

For more information please see:
Larned, S, Snelder, T, Unwin, M, McBride, G, Verburg, P, McMillan, H (2015).Analysis of Water Quality in New Zealand lakes and Rivers: data sources, data sets, assumptions, limitations, methods and results. NIWA Client Report no. CHC2015-033
Available at data.mfe.govt.nz/x/s9WT2y from the Ministry for the Environment dataservice.

This dataset relates to the "River water quality" measures on the Environmental Indicators, Te taiao Aotearoa website.

"Wetlands support unique biodiversity and provide important services. They clean water of nutrients and sediment, help dampen floods, provide habitat, and act as carbon sinks. They are also valued for their spiritual and cultural significance and as important sources of food and materials, such as flax. Draining them for agricultural and urban development has reduced their extent. Understanding this reduction provides insight into the loss of biodiversity and natural function.
This dataset relates to the ""Wetland extent"" measure on the Environmental Indicators, Te taiao Aotearoa website. "

When nutrients accumulate in lakes (referred to as ‘nutrient enrichment’) above certain levels, they can make the lakes murky and green with algae, and lower oxygen levels. Lakes with extremely poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species.

Trends in the following parameters are provided:
Trophic Level Index 3 (TLI)
Chlorophyll-a (CHLA)
Bottom-water dissolved oxygen (DObottom)
Ammoniacal nitrogen (NH4N)
Oxidised nitrogen (NO3N)
Total nitrogen (unfiltered) (TN)
Dissolved reactive phosphorus (DRP)
Total phosphorus (unfiltered) (TP)

For more information please see:
Larned, S, Snelder, T, Unwin, M, McBride, G, Verburg, P, McMillan, H (2015).Analysis of Water Quality in New Zealand lakes and Rivers: data sources, data sets, assumptions, limitations, methods and results. NIWA Client Report no. CHC2015-033. Available at data.mfe.govt.nz/x/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "Lake water quality: Trophic Level Index" measure on the Environmental Indicators, Te taiao Aotearoa website.

"Small amounts of nitrogen are a natural component of healthy rivers. Nitrogen in rivers can vary due to differences in land use, climate, elevation, and geology. Nitrogen is transferred from land to water and is cycled through different forms, which can have different effects. Moderate concentrations of nitrate can cause weeds and algae to grow too fast. High concentrations of ammoniacal and nitrate nitrogen can be toxic to fish and other aquatic animals.
This dataset relates to the ""Geographic pattern of nitrogen in river water"" measure on the Environmental Indicators, Te taiao Aotearoa website. "

E.coli is a type of bacteria commonly found in the intestines of warm–blooded animals (including people). When found in freshwater, it can indicate the presence of pathogens associated with faecal contamination, from sources such as waste from humans and farmed animals such as sheep and cows. E.coli concentrations can vary due to differences in land use, climate, elevation, and geology. High E. coli concentrations may cause illness in humans and animals if ingested. This is an important consideration for human health, particularly where people use the river for swimming or boating.
This dataset relates to the ""River water quality: bacteria (Escherichia coli)"" measure on the Environmental Indicators, Te taiao Aotearoa website.