Russell Basin

The Russell Basin has a population of approximately 1,700 people, largely in Babinda and Miriwinni.

The Russell River is among the least variable rivers in terms of annual flows in Australia, and the basin receives the highest rainfall in the region. The Russell River and Babinda Creek are the two key tributaries of the Russell Basin.

The upper catchment is in the relatively undisturbed rainforest environments of the Bellenden Ker Range.

The river floodplains and the lower river valley are dominated by sugarcane where the environment has been significantly modified with the loss of much of the original lowland rainforest.

The Russell Basin grade has remained ‘good’ with a score of 75 that was unchanged from the previous year.

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

Water quality

The water quality grade for the Russell Basin remained ‘good’ although the score declined from 75 to 67.

Nutrients remained ‘good’ but the score declined from 74 to 62. The dissolved inorganic nitrogen (DIN) indicator scored the lowest (46) and remained ‘moderate’, with monthly median concentrations often not meeting guideline values. Filterable reactive phosphorus (FRP) scored 77, declining from ‘very good’ in 2018-19 to ‘good’, with monthly median concentrations often meeting guideline values.

TSS (the indicator for sediment) scored 68 and the grade remained ‘good’, with monthly median concentrations often meeting guideline values.

Pesticides for the Russell Basin remained ‘good’ and scored 71, equating to over 97 percent of species protected for the risk assessment metric.

Water quality grades are based on aquatic ecosystem guidelines for protection of freshwater systems and are not based on load reduction targets for the marine environment. The results are derived from the end of catchment monitoring site at East Russell, capturing 78% of the basin.

Habitat and hydrology

The habitat and hydrology index is comprised of four longer-term indicator categories that are updated every four years: wetland extent, (updated for 2017-18), riparian extent (to be updated for 2020-21), instream habitat modification consisting of impoundment length (updated for 2018-19) and fish barrier indicators (in development), and invasive weeds (updated for 2019-20).

The annual scores for the habitat and hydrology index from 2014-15, 2015-16, 2016-17 represent the changes resulting from the addition of indicators and not changes in the indicator scores themselves, whilst the index scores for 2017-18 to 2019-20 include annual updates to the flow indicator as well as updates to the longer term wetland extent, impoundment length and invasive weeds indicators.

The Russell Basin habitat and hydrology index scored 63 for 2018-19 and the grade remained ‘good’.

The habitat modification score of 100 (‘very good’) is comprised of an impoundment length score of 100 (‘very good’) indicating that less than 1% of the total length of the waterways with a stream order of 3 or higher was impounded by artificial structures.

The fish barrier indicator method is still being developed and will be available in future report cards.

Riparian extent for the Russell Basin scored 79 (‘good’) with 5.7% from pre-clear extent to 2013. It is expected that the majority of loss is in the lowlands due to development and land use.

Wetland extent scored 33 (‘poor’) with 37.4% loss of palustrine (freshwater) wetlands from pre-clear to 2017.

The invasive weeds indicator scored 41 (‘moderate’) and represents some impacts of aquatic weeds within the Russell freshwater system including hymenachne (Hymenachne amplexicaulis), salvinia (Salvinia molesta), and pond apple (Annona glabra).

The Russell Basin grade for flows remained ‘good’. Flows in the Russell Basin retained similar characteristics to modelled predevelopment flows in their capacity to support the key ecological assets of water holes, low flow spawning fish, riffle habitats and fisheries production.

The flow indicator provides scores for each flow assessment site and this can be used to assess flows at more local scales. More information on the results of the flow indicator is available in the results technical report.

Fish

The freshwater fish assessment for 2019-20 was conducted at 14 sites in the Russell Basin. The index remained ‘very good’ with the score improving from 86 in 2017-18 to 92.

A total of 38 species were caught and included three species introduced into Australia, the guppy (Poecilia reticulata) the platy (Xiphophorus maculatus) and spotted tilapia (Pelmatolapia mariae).

The indicator for species diversity scored 91 and was graded ‘very good’, meaning many native species expected to occur were caught.

The indicator for introduced fish species scored 94 and was graded ’very good’ due to low numbers of alien fish caught (species introduced into Australia) and no translocated fish caught (Australian species that do not naturally occur in the waterway).

More information on the fish survey including the sites and the fish species list is available in the methods and results technical reports.

See the detailed reports for further information on the methods used to produce the scores and grades and detailed results