Kōrero: Public health

Whārangi 3. Environmental health

Ngā whakaahua me ngā rauemi katoa o tēnei kōrero

Sanitation and water

In the 19th century poor public sanitation caused high death and illness rates from infectious diseases such as typhoid. Banning cesspits and installing sewers led to a reduction in these diseases.

Treatment of drinking water followed much later. Most communities drank water piped straight from a river or lake until chlorination was introduced from the 1950s.

Something in the water

Since the Second World War there have been two major disease outbreaks caused by contaminated water. In 1984 around 3,500 people in Queenstown became ill with gastroenteritis after a blocked sewer overflowed into a lake near the public water supply. In 2016 a campylobacter outbreak in Havelock North made over 5,000 people violently ill and was associated with three deaths. The disease was traced to a contaminated pond close to a bore from which drinking water was pumped.

Even in the early 2000s an estimated 500,000 people were drinking water that did not meet (voluntary) standards. New Zealand had higher rates of gastro-intestinal diseases than countries such as Australia, Canada and the UK – this was partially attributed to contaminated drinking water. The Health (Drinking Water) Amendment Act 2007 compelled public water suppliers to ensure water was safe.


The effect of poor and crowded housing on public health was recognised in the 19th century. Courts could declare buildings unfit for living purposes and councils could demolish unsafe or insanitary buildings, but these powers were rarely used – neither was keen to interfere in the private housing market.

From the beginning of the 20th century flush toilets, sinks, baths, washtubs and spouting became more common in the bigger towns and cities. Houses were larger and more weather-tight. The development of hydroelectricity meant hot water was instantly available for personal and domestic cleaning. Older houses and rental properties were not always so well-equipped, which contributed to the government decision to build state houses in 1906, and on a much larger scale from the late 1930s.

From 1935 councils had to conduct housing surveys. In Auckland these revealed significant overcrowding, particularly among Māori and Pacific Island families after the Second World War. Overcrowding was linked to high rates of illnesses such as tuberculosis. While overcrowding decreased from the 1960s, it increased in some areas such as South Auckland, and contributed to an epidemic of meningococcal disease in the 1990s and 2000s.

Insulation of new homes was not compulsory until 1977. By the early 2000s about half of all houses had only partial insulation and one-quarter had none. Cold houses affected health – New Zealand had higher winter mortality rates than northern European countries. From 1996 government insulation and heating subsidies were available for lower-income earners. In 2009 subsidies were extended to all pre-2000 houses.

The Building Act 1991 was less prescriptive than earlier legislation and allowed the use of untreated framing timber. In some dwellings the cladding was poorly weatherproofed, which caused building materials to deteriorate or rot. High levels of damp and mould in these houses were linked to ill health, particularly respiratory conditions such as asthma. Building regulations were subsequently strengthened and in 2017 the Healthy Homes Guarantee Act set standards for rental homes that required them to be warm, dry and well-ventilated. From 1 July 2019 landlords signing any new tenancy agreement had to have installed underfloor and ceiling insulation or provided a heating source that ensured the home was warm and dry. All rental accommodation must meet these standards by 1 July 2021. Grants are available to help landlords meet these requirements. 

Clean air

Air pollution, caused by industrial manufacturing and the burning of coal and waste, was a problem in towns and cities by the mid-19th century. It contributed to respiratory illnesses such as bronchitis and asthma.

From the early 20th century town-planning strategies separated industrial and residential areas, but did not reduce and manage pollution. Clean-air zones were first introduced in Christchurch in the 1960s. Government legislation led to maximum allowable pollution levels, increased monitoring and clean-air zones in some urban areas. Lead petrol for vehicles was phased out from the mid-1980s to the 1990s.

Air pollution remains a public health issue in the 21st century. A 2012 report found that air pollution was associated with 1,175 premature deaths, 607 extra hospital admissions for respiratory and heart illnesses, and 1.49 million restricted-activity days.


Smoke-free environments were a new focus from the 1980s. An anti-smoking public health campaign, the ‘Great Smokefree Week’, was held in 1986. Domestic airlines banned smoking in 1987.

Smoking room

After 1990 some indoor workplaces had special ventilated smoking rooms. These were banned in 2004, apart from in rest homes and care facilities, which were allowed to have smoking rooms for residents. However, employees and visitors could not use the room.

The Smoke-free Environments Act 1990 restricted indoor smoking. Employers had to provide smoke-free and designated smoking areas. Smoking was banned on passenger aircraft and restricted to certain areas on ships and trains, and in passenger lounges and restaurants. Smoking in bars was still permitted.

Smoking in all indoor workplaces, including bars, and all indoor and outdoor areas at schools and early childhood centres, was banned in 2004. New Zealand became the third country in the world to introduce smoke-free bars and restaurants.

In 2011 all prisons became smoke-free. Some councils discouraged smoking in outdoor public areas such as parks and playgrounds – South Taranaki District Council was the first in 2005. Other councils have followed suit, and smoke-free outdoor policies have been introduced at beaches, shopping malls, and outdoor dining areas.

A ban on smoking in cars carrying children under 18 years of age was announced by the government in 2019.

Me pēnei te tohu i te whārangi:

Kerryn Pollock, 'Public health - Environmental health', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/public-health/page-3 (accessed 4 April 2020)

He kōrero nā Kerryn Pollock, i tāngia i te 5 May 2011, reviewed & revised 7 Jul 2019 with assistance from Richard Edwards