Russell-Mulgrave Estuary

The area of the Russell-Mulgrave estuary reporting zone can be defined by the pre-cleared extent of mangrove and saltmarsh remnant vegetation which is characterised by species that require periodic inundation of sea water.

This area extends approximately 1.5 km north and 2 km south of the river mouth along the coastline and extends approximately 5.2 km inland. The area includes the confluence of the Russell River and Mulgrave River and several coastal tributaries that drain into the main river channels.

The assessment area of riparian extent extends further up the river than the mangrove and salt marsh communities to the upper tidal limit and includes vegetation types that are more typical of freshwater environments.

Land use within and adjacent to the Russell-Mulgrave estuary area is dominated by grazing in native vegetation in the downstream reaches with cropping more dominant upstream of the confluence on both the Russell and Mulgrave rivers, with some residential development. The localities of Deeral and Bellenden Ker are just west of the estuary area.

The Russell-Mulgrave estuary grade has remained ‘good’ in 2023-24 and the score decreased from 68 to 66 since the previous year.

Key results

• The water quality grade for Russell-Mulgrave remained ‘good’, the score increased slightly from 70 to 71 since the previous year.
• Dissolved oxygen improved from ‘moderate’ to ‘good’ whilst the grades were unchanged for all other water quality indicators since the previous year.
• The habitat and hydrology index declined from ‘good’ to ‘moderate’, with the flow indicator decreasing in score due to the severe weather events from Tropical Cyclone Jasper.
• The flow indicator for the Russell-Mulgrave estuary declined substantially from ‘good’ to ‘moderate’ mainly resulting from poorer scores for measures of flow variability due to above average rainfall, particularly the very heavy rainfall events during December.
• Mangrove condition for the Russell Mulgrave estuary remained ‘good’ and the score increased from 70 to 77. Mangroves experienced a loss of seedlings along eroded shoreline as well as growth in past eroded areas.

The diagram below shows the detailed results for each indicator by year. Click on the timeslider to see data from previous years.