Environmental Assessment for a 10-Year Dredging and Nearshore Sand Placement Program

Client: Transport for NSW - Maritime Infrastructure Delivery Office (MIDO)
Sector: NSW State Government — maritime infrastructure planning and delivery
Timeframe: 10-year maintenance dredging program
Region: Coffs Harbour, NSW

Keeping maritime infrastructure safe and functional isn’t just an operational priority — it’s a cornerstone of community access to the coast. Together with Transport for NSW’s Maritime Infrastructure Delivery Office (TfNSW MIDO), we helped put in place a clear, evidence-based pathway to manage sand build-up in Coffs Harbour over the next decade, while working carefully within a highly sensitive marine environment.

TfNSW MIDO’s objective was to complete an environmental assessment to support a 10-year maintenance dredging program in Coffs Harbour, with an integrated plan to reuse suitable dredged sand via nearshore placement at Park Beach. The intent was to enable the dredged material to re-enter the natural northward drift of sediment, creating the opportunity to help nourish beaches north of the harbour.

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Project Location & Scope

The environmental assessment focused on the inner harbour area at Coffs Harbour, with the option to place suitable sand in the nearshore area at Park Beach in a way that aligned with the intent of Coffs Harbour City Council’s Coastal Zone Management Plan (CZMP) 2019.

Key features of the proposal:

The proposal included a practical, repeatable program designed to respond to changing conditions over time, including:

• Maintenance dredging every one to three years (subject to infill rates) across a 10-year period

• Average sediment volumes of approximately 96,000 m³ expected in most campaigns (to be confirmed via regular surveys), with the initial campaign expected to be approximately twice that volume

• Dredging of key navigation areas to minimum depths of:

• Marina navigation channel: -4.5 m lowest astronomical tide (LAT)

• Boat ramp navigation channel: -2.5 m LAT

• Sediment sampling prior to each campaign to inform suitable placement locations

• Nearshore placement at Park Beach when sand is identified as suitable

• Bed levelling after dredging, and periodic levelling of high spots created through natural shoaling and accretion

• Creation of sediment sinks at key locations to help reduce dredging frequency along entrance channels

What Blue Sky provided:

Blue Sky Planning & Environment’s role was to coordinate the environmental assessment process so TfNSW MIDO could confidently progress the program:

• We prepared the Review of Environmental Factors (REF) to support the project’s approval pathway

• We coordinated specialist studies (bringing multiple technical inputs into a single, coherent assessment)

• We acted as the main point of contact for TfNSW MIDO staff, keeping the process moving and decisions well documented

TfNSW MIDO engaged Blue Sky because of our:

• experience preparing REFs for transport and infrastructure projects

• planning qualifications to address statutory requirements

• proven track record coordinating multiple specialist inputs under tight timeframes

Project Challenges

This was a complex coastal assessment, shaped by both environmental sensitivity and real-world operational constraints.

Working within a sensitive marine environment

A key challenge was that the works needed to be undertaken within the Solitary Islands Marine Park, requiring a strong focus on:

• minimising impacts on aquatic biodiversity

• documenting and applying safeguards that are meaningful in a marine setting

• ensuring the assessment clearly explained risk pathways and mitigation measures in an accessible way for regulators and stakeholders

• liaising with relevant environmental agencies to ensure that their concerns were addressed

Designing safeguards that could evolve over time

Because this is a long-term program, the assessment needed to do more than address a “single dredge event”. A special requirement was to embed safeguards that allow the program to be reviewed and refined across multiple campaigns, informed by environmental monitoring undertaken during the project.

Consultation complexity and Aboriginal land claim context

Consultation was also a significant factor. The harbour is subject to an Aboriginal land claim, and engagement — particularly with the local Aboriginal community — required care, clarity and respect. We worked to ensure consultation inputs were appropriately reflected in both the assessment approach and the mitigation measures.

Seasonal windows and competing constraints

On top of this, delivery had to account for seasonal dredging windows, including:

• avoiding specific environmental constraints (such as bird migration periods)

• managing potential interactions with commercial fishing

• aligning with designated funding and program milestones

Outcomes and Results

Blue Sky commenced work in late 2023, and we worked closely with TfNSW MIDO through the assessment and consultation process to reach a robust determination outcome.

Approval outcome

• The REF was finalised and determined in January 2026

• The project proceeded via a Part 5 determination (REF), with TfNSW as the determining authority

What the determination enables in practical terms

Together, we established the foundations for a long-term program that supports both safety and sustainability:

• a clear, strategic, evidence-based framework to manage sand build-up within the harbour over a 10-year horizon

• a pathway to prioritise safe access to waterways and support continued use of maritime infrastructure at Coffs Harbour

• a structured process for confirming sediment suitability prior to each campaign, so placement decisions can be made responsibly

• safeguards designed to protect the coastal environment and support adaptive management, enabling the program to evolve as monitoring data and site conditions change

Put simply: the determination helps TfNSW MIDO maximise the use and sustainability of maritime infrastructure at Coffs Harbour, while maintaining a careful focus on environmental protection and community expectations.

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Client Feedback

The TfNSW MIDO project manager acknowledged Blue Sky’s dedication to achieving the required outcomes for the environmental assessment within a complex approval pathway — recognition we value highly, particularly on large, multi-year infrastructure programs like this one.

If you’d like to talk through an environmental assessment for a coastal or maritime infrastructure project — especially where sensitive environments, consultation requirements and tight delivery windows intersect — I’m always happy to have a conversation.