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The problem with stormwater

http://www.gw.govt.nz/the-problem-with-stormwater

The problem with stormwater

Updated 18 July 2012 2:12pm

Some of the main pollutants that get in our stormwater include:

  • litter and dog droppings from pavements and roads
  • detergents from washing cars on the roadside
  • dirt, leaves and lawn clippings from driveways and garden paths
  • left-over paint and water used to wash up paint brushes
  • used engine oil, oil leaks and spills, and radiator water
  • waste cement and concrete from washing down during building and renovation work
  • paint flakes and chemicals from cleaning outside walls

When pollutants like these get into the stormwater system, they can cause a lot of problems

Litter, leaves and clippings:

  • breakdown in water, using up valuable oxygen
  • turn up in waterways and on beaches, making them unattractive and potentially dangerous
  • can injure freshwater and marine animals.

Dog and animal droppings:

  • increase the concentration of hazardous bacteria in streams and rivers.

Detergents:

  • discolour waterways and cause foaming
  • cause weeds and problem algae to grow.

Dirt and sediment:

  • clog fishes' gills, making it harder for them to 'breathe'
  • reduce water clarity, making it harder for fish to find food
  • starve plants in water of necessary light by reducing its penetration
  • encourage weed growth.

Waste paint and oil:

  • cause ugly oily sheens that also suffocate stream fish and insects
  • contain heavy metals that are toxic.

Cement and chemicals:

  • kill fish and insects
  • fine particles smother stream life.