Hopley, 1970:

"The Burdekin River in north Queensland has one of the largest delta floodplains in Australia (1,250 km2) with a large sugarcane and grazing industry (Hopley, 1970). The river’s hydrology is highly modified as a succession of impoundments has been built along the river over the past 60 years. Several weirs, located in the lower floodplain section of the river within 60km of the mouth, were built to harvest water for the expanding sugar industry. The most recent developments have been the Burdekin River Irrigation Area (BRIA) (1989 first operations). Since the construction of the Burdekin Falls dam in 1986, water is released on demand to pump stations within Clare weir and downstream (sand dams) where it is pumped into either artificial channels or natural overflow distributary streams (Plantation, Sheep Station, Kalamia, Iya and Warren’s Gully) to service the BRIA and the water board areas.

With the change in hydrological regime there have been many changes in fish habitats along the streams. Changes include:

• increased flow velocities and sediment loading,
• infrastructure that creates barriers
• weed infestation
• water logging and clearing of riparian trees; and
• an overall change from seasonally isolated water bodies (lagoons) to perennial flowing streams with intermittent deep holes.

There have been massive modifications to land cover, which has changed from forested Eucalyptus woodlands, Melaleuca swamps, sedge wetlands and grassland, to cane paddocks (Hopley, 1970). However, there are also remnant wetland areas identified and conserved within the landscape that retain many of the more natural habitats and fish communities.

The water used for irrigation comes from the turbid Burdekin Falls Dam and is high in suspended sediments. This turbid water supplies a continuous nutrient load which stimulate plant growth (Section 4.2.4). However with the turbid water there may be an effect of light limitation on
submergent plant growth giving competitive advantage to the floating plants. Floating weed
infestations were usually the worst in sites that had irrigation water. Once the weed mats establish and cover a lagoon or the channels, they effectively create a chemical barrier excluding oxygen sensitive fish species."

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Source

Hopley, D., 1970, The geomorphology of the Burdekin delta, North Queensland, Monograph series number 1, Department of Geography, James Cook University, 66pp.