About this project
Fish re-snagging practices to restore reliable water supply to the Peel River and Tamworth region.
In 2019, WaterNSW implemented emergency measures to improve the reliability of Tamworth’s water supply in response to drought. The project was designed to slow the depletion of Chaffey Dam. A pipeline and pumping station were constructed between Chaffey Dam and Dungowan which resulted in water delivery from Chaffey Dam to Tamworth being undertaken via the pipeline. This meant water releases to the Peel River from Chaffey Dam could cease.
WaterNSW is responsible for implementing two measures to offset the residual impacts of the pipeline operation during drought.
- Develop and implement an aquatic habitat assessment and re-snagging plan that will install a minimum of 50 snags.
- Install self-cleaning pump screens on seven existing pumps.
Both measures provide habitat restoration and conservation measures relevant to Murray Cod and Silver Perch.
What is fish snagging?
‘Snags’ are in-stream woody habitat such as tree root masses, trunks or limbs. Snags naturally form when trees fall into the river following strong winds, flooding or drought. Snags create variation in stream flow needed by native fish and provide habitat for a range of aquatic wildlife. Snags are favoured habitats for native fish, providing ideal conditions for breeding, feeding, shelter and rest. They also play a critical role in providing a place for bacteria, algae and micro-organisms to grow.
GeoLINK’s services for an improved Peel River
WaterNSW engaged GeoLINK to provide services for the re-snagging of the Peel River. Services provided for this project are to:
- Assist with identifying suitable snagging sites within the Peel River between Chaffey Dam to Tamworth.
- Investigate Aboriginal Heritage Impacts, Environmental Impacts and obtain approvals.
- Provide scoping documentation for works at each individual site.
- Identify potential sources of appropriate logs and materials to enable the installation of 50 snags.
We also provided high level advice regarding assessment and approval pathways.
Healthy river, healthy fish
The Peel River has known populations of threatened species such as Eel Tailed Catfish and Silver Perch as well as popular recreational angling species of Murray Cod and Golden Perch (yellow belly). But de-snagging and removal of vegetation from the riverbanks have contributed to a decline in fish stocks.
Re-snagging efforts are a common way to enhance native fish habitat. Creating a more robust fish community in turn creates improved benefits for recreational fishers.
Fish snags were previously seen to create a number of negative impacts to rivers so many were removed from river systems throughout Australia. But many of those impacts have been overstated or proven incorrect.
Snags play an important role in protecting the riverbed and banks from erosion. They also give fish places to hide and forage, create variable flows, and introduce nutrients to the river as they decompose. That’s great news for anglers on the Peel River, who’ll benefit from healthier fish populations.
Finding sites for 50 snags
Identifying 50 suitable sites for snags on the Peel River provided some challenges. It required a methodical approach and thorough process.
- Potential sites were identified considering land ownership and access.
- Site inspections were conducted at each potential location.
- The suitability of each site was determined and defined as either “Not suitable”, “Suitable” or “Ideal”. Some sites had the potential for multiple snags to be placed within the location and surrounds.
- Constraints were considered including those that may pose a threat to the project.
GeoLINK’s expertise helped to move the project forward
A number of constraints were identified at potential sites during the site inspection stage of the project that needed to be considered and addressed. This included:
- weeds
- vegetation pruning and removal
- soil erosion and sedimentation
- potential animal habitat disturbance
- land and water pollution from plant and equipment operation
- rehabilitation after snag placement and monitoring
GeoLINK undertook a project Biodiversity Assessment Report to ensure potential biodiversity impacts are identified and mitigated.
Our Environmental Engineering and Science team have relished the opportunity to be involved in this project. The experienced team combine their knowledge of engineering and environmental processes to provide realistic, integrated and cost-effective design solutions for your project.
Get in touch to find out more about how we can help with your next project.