Sandringham Lagoon

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Reef Catchments Ltd

Council

On-ground work

(none)

Mackay Regional Council

(not documented)

(not documented)

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Ongoing

Sandringham Lagoon is a 2.2 km long wetland located at the headwaters of Sandringham Creek in Balberra (South of Mackay). The lagoon retains habitat for waterbirds and migratory fish species and acts as a retention basin for run off from a sugar cane dominated catchment. The environmental threats included fish passage barriers, invasive weed infestations choking the system and poor riparian vegetation condition.

Significant restoration works were undertaken at the lagoon from July 2006–August 2008. The tasks undertaken were:

• water quality sampling
• fish community sampling
• observations of bird communities
• consultation with landholders and stakeholders
• public education
• spraying of weeds
• mechanical removal of weeds using an excavator and an aquatic weed harvester
• construction of lagoons to act as fish refuge and sediment traps
• construction of a fishway
• revegetation of banks and
• provision of incentives for landholders to control weeds after project completion.

Effective communication with the landholders surrounding the Lagoon allowed for:

• access at all times for all works
• dumping points for the removed material
• land adjacent to the lagoon to be used for construction of sediment and fish refuge ponds.

A total of 30,000 tonnes of material was removed from the Lagoon, consisting mainly of water hyacinth, water lettuce and hymenachne. 3,640 trees were planted along the riparian zone with a success rate of approximately 85%. By removing the weed mat, water quality was increased significantly. Dissolved oxygen, water clarity and pH levels all improved. The large number of fish that have returned to the lagoon initiated a return in many bird species.

More recently, in late 2015, an outbreak of water hyacinth is overtaking the Council’s ability to manage the weed using chemical control. Plans are in progress for mechanical removal of the weed and mulching of the biomass on site. The proposal is for the beneficial reuse of the mulch during subsequent riparian revegetation projects as well as surrounding landholder education programs to reduce the nutrient load entering the waterway.

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