Water pollution in the West Coast, New Zealand
Water pollution is an environmental issue on the West Coast of New Zealand.
Water resources and water pollution come under the jurisdiction of the Resource Management Act and is controlled by the regional councils - for the West Coast it is the West Coast Regional Council.
A 2008 State of the Environment report showed that:[1]
- acid mine drainage has significant effects on freshwater ecosystems
- less than 5% of the water samples taken from contact recreation sites indicated unsafe swimming conditions. 17 sites are monitored along a length of 600 km[2] of coastline that drains hundreds of rivers. For the upper 150 km, north of Westport, there is no monitoring[3]
- point source pollution has decreased and nonpoint source pollution has increased
- Water deterioration occurs at the lower levels of a number of catchments
- Water quality improvements were evident in a number of water quality indicators.
Issues
Grey River
Raw sewage is discharged into the Grey River after heavy rainfall. Historically, sewage and stormwater from Greymouth, Cobden and Blaketown was discharged directly to the Grey River. Changes to the Grey District Council's wastewater schemes provide separation and treatment for sewage, except during periods of high rainfall, such as spring, when the capacity of the sewage treatment is exceeded.[4]
Acid mine drainage
The West Coast has a long history of mining and some of the waterways suffer from acid mine drainage as a result of the leaching of acidic water from mining activity.
Drinking water
Eighty two percent of the population is supplied by reticulated drinking water with 28% having some form of treatment to improve water quality. None of the water supplies reach drinking water standards.[5]
Lake Brunner
The water on Lake Brunner has been monitored since the 1990s and it shows that the water quality of the lake is declining.
Ngakawau River
North of Westport Water from the Stockton open cast coal mine pollutes the Ngakawau River.
Mokihinui River
50 km north of Westport. This river has a 68,000ha catchment, which is largely pristine[6] except for the lower coastal region downstream of the ranges. Nevertheless, the two major farms work hard to protect the river via planting of riparian strips and strategic farm management practices.
See also
References
- ↑ Horrox, J. (June 2008). "West Coast Surface Water Quality" (PDF). West Coast Regional Council. Retrieved 8 August 2010.
- ↑ http://www.wcrc.govt.nz/about_us/our_region/
- ↑ http://www.wcrc.govt.nz/state_of_the_environment/water_quality/contact_recreation_risk.htm
- ↑ Bromley, Tui (31 October 2012). "Effluent with your whitebait?". The Greymouth Star. The New Zealand Herald. Retrieved 31 October 2012.
- ↑ "Environmental determinants in the West Coast" (PDF). Joint report by the West Coast DHB and the CPH–West Coast. 2008. Retrieved 8 August 2010.
- ↑ http://www.protectedplanet.net/sites/Mokihinui_Forks_Ecological_Area