Reclaiming a landslip zone at Doon Doon creek

Introduction

Siyavash Doostkhah and Greta Kelly’s Doon Doon property lies where Nightcap National Park and Mount Jerusalem National Park meet. 

Since 2012 they have served as caretakers to the property which is home to diverse ecological communities including:

• Brushbox-Flooded Gum wet forest
• Brushbox-Walnut wet forest
• Subtropical Rainforest. 

Their vision has been to reconnect the property with the adjacent national parks and restore the natural balance disrupted by decades of historical agricultural degradation. 

While pristine rainforest remains in sections of the property, other parts had been overtaken by invasive weed species. Through years of committed effort, they have carefully managed invasive growth while planting thousands of native trees, including several threatened rainforest species, to foster biodiversity and soil health.

Challenge

To repair extensive landslip damage and habitat loss in difficult terrain on private property bordering National Park. 

In late February 2022, a catastrophic rainfall event struck the Northern Rivers region, delivering over 800mm of rain in just seven hours.

This deluge followed several months of persistent rain, resulting in a cumulative rainfall of 1,200mm between October 2021 and February 2022. 

The consequences were devastating; multiple landslips occurred across the property, including one of the largest in the region—an 18,000m2 scar running 1,000 meters in length, carving through native vegetation and engulfing Doon Doon Creek. 

The immediate aftermath presented several critical issues:

• extensive tree loss and blocked access routes
• highly unstable deposited material, prone to erosion and micro-slumping
• exposed slip faces with spring activity and ongoing risk of further movement
• denudation of creek banks, with significant habitat loss and hydrological disruption.

"It was really unstable during the first 6 months and rocks would move really easily. It was like quicksand for several metres around the creek. It was quite dangerous; it would look dry and then I would get stuck down to my knees in it. The dozer fully sunk when we tried to do sections of driveway."

- Siyavash Doostkhah

6 months after the event, new and unexpected challenges emerged like:

• the spread of opportunistic weed species on disturbed soil
• difficult terrain with steep, unstable slopes
• increased land management challenges due to degraded soil structure and compromised drainage.

The physical and emotional toll on the landholders was profound. Siyavash knew that restoration would require more than immediate intervention; it would demand years of strategic planning, continuous work, and outside assistance.

Solution

The Landslip Recovery Project was a regionally coordinated response initiated by the Border Ranges Richmond Valley Landcare Network and supported by Tweed Landcare, Brunswick Valley Landcare, and Richmond Landcare. Funded through North Coast Local Land Services, the project provided tailored remediation plans for high-priority conservation lands affected by landslides.

Remediation reports included:

• detailed site assessments including:
  • a helicopter inspection by soil conservation service
  • a soil landscape report
  • drone seeding proposal.
• a landslip revegetation plan by a bush regenerator which included:
  • the environmental background information of the property
  • recommendations
  • a site plan
  • native and exotic vegetation assessments.

From the report, Siyavesh and Grace proceeded with 3 strategies to restore their property. These strategies were:

1. Weed management
2. Hand planting
3. Drone seeding.

LLS Funded Landslip Recovery Initiatives

To support the recovery and stabilisation of the landslip area, Local Land Services (LLS) provided funding for a multi-stage restoration program, which included:

• revegetation efforts
• targeted weed control
• ongoing maintenance and site support.

In Autumn 2023, 2,000 native trees were planted and maintained across 0.5 hectares to assist in slope stabilisation and habitat restoration.

From July 2023 to June 2024, primary and follow-up weed control was carried out over 2 hectares along the landslip-affected area. Integrated methods such as stem injection, cut/scrape and paint, and overspraying were used by the bush regeneration team. Key invasive species targeted included:

• Giant Devil Fig
• Lantana
• Crofton Weed.

To ensure the long-term success of revegetation and weed control efforts, LLS also funded follow-up maintenance across 2.5 hectares. This included bush regeneration contractor works from December 2024-June 2025, focusing on both the landslip zone and adjacent riparian planting areas.

"I would suggest other landholders to prioritise what they can do and stage the works to not overwhelm themselves. Don’t give up and plan to a scale that is achievable to you. Utilise your community and networks as much as you need to assist you."
- Siyavash Doostkhah

Outcomes

Despite the overwhelming devastation, the land has responded with resilience. 

By focusing on achievable, incremental steps and seeking support from collaborative networks, the landholders have transformed a disaster zone into an emerging forest.

• Native trees, including some rare species, are now flourishing. In one particularly successful zone, natural regeneration outpaced planted trees in height and strength by 4 to 8 times.
• Over 2,900 native trees were hand-planted across multiple stages in 2023, providing critical stabilisation. While roughly 20% of these did not survive the first year, replacements have since been added.
• Areas inaccessible by foot were seeded via drone by AirSeed (funded by WWF) with mixed outcomes due to poor germination in control environments and lack of follow-up aerial monitoring.
• Cleared landslip zones saw remarkable natural regeneration of native rainforest species. These volunteer seedlings now form canopy layers, shading out invasive plants and stabilising soils.

The success of the rehabilitation efforts was underpinned by the unwavering commitment of Siyavesh and Grace, who dedicated countless hours to maintaining the plantings and conducting ongoing weed control to ensure the long-term sustainability of the project.  

"Biggest lesson was don’t lose hope. You’re in the middle of a disaster zone and it feels like too much. Take a breath and realise that its part of a natural process. It taught me to look at the landscape with a different lens, to see how this process has been over thousands of years and to see the formation of the valley in the landscape. Don’t be afraid to ask for help – it's beyond us as landholders at this scale."
- Siyavash Doostkhah

Related information

• Revegetating your property
• Managing soil erosion