FAQs

Woronora River is naturally subject to sediment build-up of sandy shoals. Sediment is washed into the river from nearby bushland and residential areas or by riverbank erosion, usually after periods of heavy rainfall. This leads to the bed of the river gradually building up with sediment.

Dredging is the process of removing sediment build-up from a riverbed to improve access for vessels. It is usually carried out with specialised dredging vessels and excavators.

Council has been monitoring the riverbed levels and responding to community requests, carrying out periodic dredging to maintain sufficient depth in priority locations, such as public wharves.

This Plan will set out a proactive, long-term approach to ensuring safe and reliable access throughout the Woronora River into the future.

As per Council’s Dredging Policy, the NSW Government has full financial responsibility for dredging of navigational channels as the bed of the river is owned by the NSW Government. 

Council is available to manage dredging activities on behalf of NSW Government and residents, subject to all works associated with dredging activities being fully funded. 

We will continue efforts to secure grants from the NSW Government to improve navigation of the river. Council is aware of the NSW Government's 'Boating Infrastructure & Dredging Scheme' that will fund the development of new and improved public boating infrastructure and enhanced public access to NSW waterways. The Scheme replaces the previous grants program 'Boating Now'. Registrations of interest are expected to open in late 2024, with successful applicants announced in 2025.

Find out more about the Scheme on the Transport for NSW website.

In preparation, we will be surveying the riverbed again in October 2024 to inform the navigational dredging strategy. The start of dredging will depend on when the NSW Government awards the funding for Council to carry out the work.

The draft Plan considers the Woronora River from the Pass of Sabugal and The Needles downstream to the outlet to Georges River, as shown in the study area map.

A community survey of Woronora residents was conducted in December 2021 to inform the draft Plan. We received valuable feedback from the community, including vessel and river usage, concerns and aspirations for the river, and identifying areas with navigational issues. 

We are now inviting the community and stakeholders to review and comment on the draft plan before it is finalised.

The key recommendations in the Woronora River Dredging Management Plan are:

-    Proactive assessment of the navigation channel, including surveying the riverbed levels every two years (or four years after dredging) to establish a minimum trigger for dredging

-    Ongoing dredging at priority areas as needed, such as Gweneth Thomas Wharf and the Rural Fire Service facility 

-    Navigational dredging (potentially every 7-10 years as determined by riverbed surveying) at the seven highly-sedimented problem areas identified along the river, including:

• Kings Flat
• The reach of the river near Deepwater Estate
• The confluence of Forbes Creek
• Just slightly downstream of the Bonnet Bay boat ramp
• The Woronora River near its confluence with Still Creek
• Near the entrance to Bonnet Bay
• The confluence of the Woronora River and the Georges River.

There are a range of solutions available to address ongoing sedimentation build-up, including:

• Removing the material through dredging (the focus of this plan)
• Reducing the source of material, through stabilisation of the riverbank to reduce erosion or catchment management, such as erosion controls on development sites and management of exposed areas
• Intercepting the source of the material through stormwater treatment devices in the catchment.

Dredging must be considered in the broader context of catchment and waterway management, including the Woronora River Estuary Management Study and Plan (2008). 

Council is developing a Catchments & Waterways Strategy & Implementation Plan which will assess methods for sediment management across the Sutherland Shire.

This Plan is focused on the Woronora River. Council is developing a Catchments & Waterways Strategy & Implementation Plan which will assess dredging management strategy across the Sutherland Shire.

Dredging for flood mitigation purposes was previously examined in the Woronora River Floodplain Risk Management Plan but not recommended for inclusion due to the sheer volume of sediment that would need to be removed to reduce flooding impact, the significant cost associated with this and additional environmental impacts to marine life and bank erosion.