THE Townsville monsoon had little impact on water quality in the region, including the outer reef, a new report shows.
The Townsville Dry Tropics Report Card 2019 indicates that despite 1.13 million metric tonnes of water discharging from the Ross River into Cleveland Bay, it had minimal impact on the environment.
Dry Tropics Partnership for Healthy Waters chair Diane Tarte said the report showed that overall, water quality across the Townsville region is moderate to very good.
"The February 2019 flood event saw 1.13 million metric tonnes of water discharged from the Ross River into Cleveland Bay, causing riverbanks to erode and nutrients, sediment and litter from the urban environment to flow into the rivers and marine environment," Ms Tarte said.
"Despite the social and economic impacts of the flood event, research suggests minimal impacts so far to most environments, including offshore coral reefs.
"Flood plumes reached the outer reef within five days but dissipated five days later."
Ms Tarte said seagrass meadows showed a decline in biomass following the floods, however, the overall area of meadows had remained above the long-term average.
This was likely due to the good growing conditions from previous years, which provided some resilience within the seagrass ecosystem.
The series of small estuaries in the Ross and Black River basins all scored positively, with a B grade (good) for water quality and habitat.
Cleveland and Halifax Bays each scored a C (moderate) for water quality and habitat.
The offshore marine environment scored the only A (very good) in for water quality.
Launched last year, the Dry Tropics Partnership for Healthy Waters is a collaboration between community, industry, science and government in the Townsville region, to monitor waterway health and promote management actions.
The report card assesses the condition of waterways against agreed management objectives and identifies gaps in monitoring data, all of which can be used to expand knowledge on waterway health.
"We're excited that the report card has expanded to include three new data sets around additional monitoring, which includes a new litter indicator, citizen science data on hard coral cover and 14 new monitoring sites in the Black Basin," Ms Tarte said.
The Townsville Dry Tropics Report Card is one of the five regional report cards in the Great Barrier Reef catchments that produce an annual snapshot of ecosystem health and water quality condition of local waterways.