NSW Water Hyacinth Strategic Plan

Water hyacinth is covered under a Biosecurity Zone in NSW. It invades waterways and is considered one of the world’s worst weeds as it can completely smoother water ways and has a long seed longevity of at least 25 years.

Conditions are ideal for water hyacinth in most freshwater waterbodies of NSW. This is a significant threat because water hyacinth:

Blocks irrigation channels and equipment
Reduces access to waterways for recreation
Restricts livestock access to water
Impacts native fauna and plants
Blankets the water surface, reducing water quality through decreased light absorption, oxygen levels, temperature and Ph.
Damages fences and pasture in floods
Provides favourable conditions for mosquitoes to breed

Water hyacinth is found in every continent other than Antarctica and is a serious weed in many areas where it has been introduced. Significant economic costs can be caused by water hyacinth infestations. An infestation in Lake Victoria in Africa is estimated to have up to U.S. $150 million in economic costs via impacting fisheries and blocking water channels.

In NSW Water hyacinth grows along the NSW coast from the Queensland border to Kiama in the South East region. The Macleay, Clarence and Richmond catchments have the worst infestations on the North Coast. Large infestations were present in the Hawkesbury River in Greater Sydney during the 1990s. Small remaining populations are still being controlled.

In the North West region, water hyacinth was identified near the Gingham Watercourse near Moree in 1955. By 1976 it had become a major infestation covering 7000 ha. Despite control efforts, a significant seed bank still remains across the region. It has since moved further west, threatening the Murray-Darling system. It is imperative that we contain the known water hyacinth infestations and stop the further spread of this weed in New South Wales.

The department led the development of the NSW Water Hyacinth Strategy which details strategic direction for effective detection and control of water hyacinth. If you would like more information about the Strategy, please contact weeds@dpird.nsw.gov.au

Think you may have seen water hyacinth? Call us on 1800 680 244.

The water hyacinth strategic plan is available to view or download