Macquarie River rafts

Information about debris rafts along the Macquarie River.

Following previous flood events in NSW, debris rafts have formed along a stretch of the Macquarie River, between Warren (Top) Weir and Marebone Weir in Warren.

The debris rafts are comprised of organic and human-derived materials.

The Environmental Services Functional Area (the EPA is the lead agency) has been working with supporting government agencies and the community as part of a coordinated environmental recovery effort.

The NSW Government held two drop-in sessions in 2023 in Warren to discuss management options for the rafts.  The sessions provided feedback and insights into community concerns and the potential risks associated with rafts and proposed approaches to managing the rafts.

Following inspections in December 2023, a recommendation was made to extend the scope of the project from partial removal of two rafts to removal of human-made debris from the Macquarie River rafts between Warren (Top) Weir and Marebone Weir, including from the river shoreline. Identifiable woody weed debris, like willow, will also be removed from rafts.

The EPA has appointed a contractor to complete the works which commenced on 8 April 2024. All works are being conducted in a manner that is safe to human health and the environment.

Where native woody debris is over 300mm in diameter and 3m in length it is not being removed entirely from the river (in line with Department of Primary Industry’s snag guidelines) but is being tethered to the bank to assist with bank stabilisation and preserving aquatic habitats.

Water monitoring upstream and downstream of rafts is being conducted during the works and immediately after the work.

Map of raft locations as at June 2023

Since the clean-up commenced on 8 April, approximately 302 cubic meters of woody debris and 23 cubic metres of human-made debris has been removed from the Macquarie River. 

What have we been up to recently? 

A grapple and pulley system has been designed and modified, with help from an engineering firm based in Warren, to assist with debris removal. The system allows us to drag debris across the river to where it can be accessed by a long-reach excavator for removal.  

Works are continuing on Raft 1 and Raft 4. A small excavator is being utilised on Raft 4 to lift material collected by boat crews in bulka bags. A boat crew continues to remove debris by hand on Raft 1. 

A grapple designed to make debris retrieval easier, Warren

What’s happening to debris once it has been removed from the River? 

Debris is being taken to the Ewenmar Waste Depot in Warren. We recently visited the Depot to observe how debris is being managed once it arrives at the depot. It’s important that all debris collected as part of this project is managed in line with the waste hierarchy to ensure waste is managed efficiently, sustainably and safely. 

The EPA is satisfied with how the Depot is managing and treating debris from this project. Ewenmar Waste Depot doesn’t currently accept debris classified as hazardous such as chemical drums. While a suitable option is being identified for hazardous waste such as chemical drums, hazardous debris is being taken to the Public Works depot in Warren. 

Ongoing works on Raft 4, Warren

Boat crews working on the upstream section of Raft 4, Warren

Monitoring update

We are monitoring the Macquarie River to review water levels and flow, water quality and erosion potential at the rafts throughout this project. This monitoring is being conducted by the Science team at the Department of Climate Change, Energy, the Environment and Water (DCCEEW).

The DCCEEW Science team were recently on site to collect the data from water quality monitoring instruments located near rafts 2, 4, 5 and 7. The debris rafts are dynamic and do break up and change over time, particularly when they are floating and not anchored in place behind logs and fallen trees. 

The DCCEEW Science team has confirmed that the monitoring found no evidence of any acute impacts on electrical conductivity (dissolved solids) or dissolved oxygen concentrations related to debris removal works. The monitoring instruments show that oxygen and conductivity levels remain within the normal ranges expected for the Macquarie River. 

Excavator removing woody debris from Raft 4, Warren

Safety is the EPA’s number one priority. Our staff supervise works on the ground, and water levels are monitored daily. If you have any concerns or questions related to the works please email us at engagement@epa.nsw.gov.au.

Since the clean-up commenced on 8 April, approximately 177 cubic meters of woody debris and 14 cubic metres of human-made debris has been removed from the Macquarie River.

Surf Life Saving NSW has now concluded their drone surveillance of the river. This valuable data will assist us in confirming the current size of debris rafts and identifying any secondary debris accumulations that we may not have been aware of previously. Works were paused briefly last week due to wet weather, but this didn’t affect the long-awaited removal of a car body deposited by the 2022 floods from the banks of the River at the Industrial Access Road Bridge just outside of Warren township. 

Car body before removal near Industrial Access Road Bridge, Warren 

Car body being removed near Industrial Access Road Bridge, Warren

Raft 4 staging area set up, Warren

Where have we been working?

Work has commenced on Raft 4 and near Raft 2. Heavy machinery including an excavator, a bobcat and a long-reach excavator with a 55 ft boom made their way to site last week to assist with the clean-up.  

Red circles indicate where work is ongoing, Warren

Since our last update work has continued on the removal of a variety of human-made debris from the rafts. Recent items include chemical containers, hard and soft plastics, metal and plastic drums, polystyrene, treated timber, tyres and white goods.

Raft 4 before works, Warren

Raft 4 before works, Warren

Raft 4 during works, Warren

May Community drop-in

The 4th community drop-in session held last Wednesday 1 May was well attended by Warren community members interested in hearing about the progress of the Macquarie River raft project. We were able to let the community know that work on Raft 1 is now largely complete. As the water level changes, additional inspections will take place to determine if further work is required. We are aware of secondary debris accumulations in this area and assessment of these accumulations is ongoing.

 

Since 8 April when the clean-up commenced, approximately 142.6 cubic meters of woody debris and 5.3 cubic metres of human-made debris has been removed from the Macquarie River. 

Debris was identified using aerial surveillance, on-ground and on-water mapping, reports from the community and reports from supporting government agencies, including the Warren Shire Council. Our contractors, Northern Rivers Marine Services (NRMS), are using multiple resources, including slings, chainsaws, boats, land vehicles and hand-picking to carry out the clean-up. 

Where have we been working?

Work has commenced on Raft 1.  

A scientist from the Department of Climate Change, Energy, the Environment and Water (DCCEEW) has been on site to train the contractors to identify woody weed species in debris, including willow, so they can be removed from rafts. 

Red circle indicates where works have commenced, Warren

What types of debris have we been collecting? 

We have removed a variety of human-made debris from Raft 1 including gas bottles, plastic bottles, a tyre, a hot water system, a box freezer, plastic drums, hard and soft plastics, glass, polystyrene and chemical containers. Woody debris including willow has also been removed from Raft 1.  

Raft 1 during works, Warren

Raft 1 during works, Warren

 

Raft 1 during works, Warren

Woody debris removed from Raft 1, Warren

Large skip bin for debris removal, Warren

Woody and human-made debris removed from Raft 1, Warren

Human-made debris removed from Raft 1, Warren

Drone surveillance

Please be aware, you may notice drones in the vicinity of the works between 19-30 April 2024. The drones are operated by Surf Life Saving NSW and are assisting us in identifying debris in the Macquarie River, between Warren (Top) Weir and Marebone Weir in Warren.