It's time for homeowners to clean up their act, with a new survey showing lead, mercury and pesticides washing into Wellington Harbour.
The sediment in the harbour is contaminated by several heavy metals, the Greater Wellington Regional Council survey found.
Levels of copper, lead, zinc and mercury exceed national guidelines.
Council environment spokesman Chris Laidlaw said that, for the most part, private companies around the region had "got their act together" but households needed to follow their lead.
Many people did not think as they washed paint, detergent, and motor oils into stormwater drains, he said.
"Few people appreciate every last drop of that contaminant will end up in the harbour."
Regional council coastal scientist Megan Oliver said the contamination was not a health threat to people swimming, diving, food-gathering or fishing.
But if the pollutants increased, they could become toxic to the tiny animals that lived in the sediment, vital to the food chain and marine environment.
The harbour floor would be tested again in two years.
- The Dominion Post
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