Kōrero: Sewage, water and waste

Whārangi 8. Water pollution

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Ad hoc approach to pollution

Water pollution increased throughout the 19th century but it was slow to gain national attention and action. The Pollution of Water Bill, introduced to Parliament in 1912, gave more rights to polluters than those affected by pollution, and was eventually dropped. A River Pollution Prevention Bill drafted in 1937 also failed to gain support, while the inter-departmental committee on pollution convened in the same year only made ad hoc recommendations.

A 1947 nationwide survey of water pollution found plenty of it. However, there was no political will to deal with pollution until 1953, when the Water Pollution Act was passed. This established a Pollution Advisory Council, which devised a tentative classification for water quality and developed model by-laws for trade wastes – but had no powers to actively monitor and control water pollution until 1963. The Water and Soil Conservation Act 1967 led to the 1972 creation of the Water Resources Council, which took over pollution control and water-quality responsibilities, working in collaboration with the Regional Water Boards established by the act.

Untreated sewage

By the 1970s industrial waste discharges had resulted in dead streams and highly polluted rivers in some urban areas. Cities discharging untreated sewage via ocean outfalls had shore pollution. As towns grew, all sewerage systems needed extending and upgrading.

In the 1950s, 27% of the population was not connected to a sewer. Some 40% of sewage was going untreated into the sea or streams. The rest received only primary treatment (removing solids) before discharge, or a minuscule amount of secondary treatment (aeration to help reduce its biological content). By the early 1970s there was little change in those without sewers, but untreated discharges had almost halved, with most of the change being primary treatment. In Auckland a major civic battle was fought from the 1930s to the 1950s over whether to pump the city's raw sewage further out into Waitematā Harbour, or to build land treatment facilities beside Manukau Harbour and discharge treated water only. The pro-treatment party won.

The last major centres to stop dumping raw sewage into the sea were Wellington and the Hutt Valley (in 1998 and 2001 respectively).

Starry water once again


The Waiwhetū Stream (ironically, Waiwhetū means ‘star-reflecting water’) in the Hutt Valley was sullied with industry waste for over 100 years, making it the most polluted stream in the Wellington region. Contaminants included toxic heavy metals. The commitment to a full decontamination and improvement programme was finally made in 2008, with the total cost of $6.4 million being shared between the Hutt City Council, the Ministry for the Environment and Greater Wellington regional council. The clean-up includes replanting banks with native plants.


Water pollution gets worse

Māori opposition to discharging liquid and solid waste into clean water was central to some of the first Waitangi Tribunal claims in the late 1970s and 1980s. Environmental claims to the Waitangi Tribunal decreased after the Resource Management Act was passed in 1991. This made explicit provision for Māori concerns to be heard as part of the planning process. It also contained provision for national policy statements, which set national standards and ways to achieve them for key environmental resources.

As water quality continued to decline in the 1990s and 2000s, a policy statement for fresh-water quality became more urgent. It was finally drafted and put out for evaluation in mid-2008. The Ministry for the Environment had issued water quality guidelines for fresh water in 1992, and had taken over the Water Resources Council’s role of classifying and monitoring water quality. It also had a programme of practical work around fresh and waste water since the 1990s. Despite this, water quality was getting worse, not better. Many urban waterways were badly polluted. Water clarity can be deceptive as it does not show contamination by heavy metals and other toxins in sediments.

Me pēnei te tohu i te whārangi:

Christine Dann, 'Sewage, water and waste - Water pollution', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/sewage-water-and-waste/page-8 (accessed 14 June 2024)

He kōrero nā Christine Dann, i tāngia i te 11 Mar 2010