The Stream

Cape York Water Partnership Network News 

Summer 2023-2024

Special Flood Edition

As I’m sure you all know, Cyclone Jasper, and the ensuing floods, created an overwhelming ending to 2023. 

The floods put our Eastern Cape York Water Quality Program (ECYWQP) teams into overdrive - sampling floodwater, documenting landslides and other erosion, and supporting the communities that were inundated. Some of our staff and many of our friends and colleagues have been personally affected by the floods, and are still clearing out the mud and adjusting their lives

In addition to the personal losses, the destruction of river riparian zones, extreme sediment loads flowing to the reef, and coral bleaching along the coast have been shocking

With this as our current backdrop, this newsletter has a strong focus on the impacts of Cyclone Jasper, including some good news regarding how the Eastern Cape York Water Quality Program erosion projects held up under extreme pressure plus reflections on the also extreme 2023 fire season. We hope you find it informative.

Dr Christina Howley

Water Quality Program Director

Cape York Water Partnership 

Left: Landslip at Cedar Bay (Photo: Tim Hughes) and Christina collects a water sample on the Annan Bridge

The Eastern Cape York Water Quality Program is funded by the partnership between the Australian Government’s Reef Trust and the Great Barrier Reef Foundation.  

We acknowledge the Eastern Kuku Yalanji people on who's Country we at CYWP are based. We respectfully publish below many photos of this land that has been severely impacted by Cyclone Jasper and our thoughts remain with the Wujal Wujal and other local communities.

Above: Eric preparing dataloggers for deployment into the rivers

A rapid preparation for the wet thanks to Cyclone Jasper  

CYWP Water Quality Monitoring Project

As Cyclone Jasper approached in mid-December, the water monitoring team at Cape York Water Partnership were in a race against the clock to prepare for the first big rains of the season. With all hands on deck, we installed equipment into the Normanby, Starcke, McIvor, Endeavour and Annan Rivers, and Annan River tributaries.   

This equipment includes dataloggers that measure turbidity (how dirty the water is), pressure gauges that record river height, and Acoustic Doppler Current Profilers (ADCPs), which use sound waves to measure water velocity. The data collected by this equipment helps us estimate how much sediment (dirt) is travelling out of the rivers and to the reef.  

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We capture data from the first rains of the season- the ‘first flush’, and then continue to monitor for the remainder of the wet season, for the most accurate sediment load estimations. We can’t install some dataloggers into dry or low flowing creeks, so have to wait for the rains to come. This time the rain came a bit quicker than we had expected with Cyclone Jasper, and then just didn’t stop!  But having this equipment in place has allowed us to document the extreme conditions of this event. 

Much to our surprise, most of the equipment we installed remained intact. We only lost one turbidity datalogger from the Normanby at Battlecamp (where the river rose above 21m), however some of the dataloggers, and the infrastructure around them, were damaged. With back-up devices also overwhelmed by the flood intensity, we are still piecing together the missing data to tell the full story.  

A huge thank you to everyone - staff, rangers and boat skippers - who helped us fast track our pre-wet season preparations as Jasper approached!   

Christina installing a turbidity datalogger in a pipe overhanging the Normanby River at Kalpowar Crossing

Nicko helps out installing a turbidity datalogger in the Starcke estuary

Flood levels and water quality across the Annan Catchment in response to Cyclone Jasper 

Cape York Water Partnership

After Cyclone Jasper (Category 2) made landfall on 13 December 2023 it became a slow-moving low-pressure system across the northern Wet Tropics and southern Cape York Peninsula.  Over the following six days, 2970 mm of rain fell at Rossville (Lloyd unpublished data) in the upper Annan Catchment, with much more likely on high mountain peaks. 

Over 1440 mm fell over 24 hours from the 17 to 18 December, triggering major landslide and debris flow mass wasting. The Annan River at Beesbike (above Little Annan bridge) peaked on 18 Dec 2023 at around 14 m, but the gauge was severely damaged right at peak flood and stopped recording, so these data are to be confirmed. 

Left: Top- NASA Aqua MODIS satellite image from 24 December shows green water from Cairns to Cape Bedford reaching out beyond the outer reefs Below- for comparison, same area showing clear water on December 4th before flooding

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Already at major flood stage at 6 m on 17-Dec at 7:00, the river rose another 5 metres in 15 hours to 11.2 m at 22:00 when major damage began, and then rose another 2 metres overnight to 13.3 m damaging property and threatening many lives. The previous maximums were 10.4 m in 1999, 9.5 m in 2004, and 10.05 m in 2014. Other rivers also experienced their flood of record including the Bloomfield and Laura (gauges damaged), and the West Normanby, Normanby at Battle Camp, and Normanby at Kalpowar Crossing. Long-time residents say this is by far the most extreme rainfall and flooding they have witnessed or heard of (but exceptions do exist such as the 1899 Cyclone Mahina at Bathurst Bay).  

CYWP scientists, along with state hydrologists, have been monitoring river height, velocity, discharge, and suspended sediment concentrations at six gauges across the Annan (Big Annan Bridge, Oakey Creek, Trevethan Creek, Scrubby Creek, Little Annan at Beesbike, upper Annan at Collingwood). Surprisingly, four of the gauges were not damaged during the floods, but the Little Annan at Beesbike and Big Annan Bridge gauges were damaged just after peak flood conditions. Data reconstruction will help fill in gaps from this damage. Therefore, the river and tributary discharge (volume of water) and sediment loads can’t be estimated until all the data are quality controlled and analyzed.  

Trevethan Creek was heavily impacted by extreme rain and debris flows in the upper catchment, which pushed water and sediment flood waves past the Mulligan Highway bridge. The creek peaked at 9.2 m, which was 2-3 metres above the bridge deck road surface. Turbidity values maxed out at > 4000+ NTU (nephelometric turbidity unit, a measure of water cloudiness due to particles), which is eight  to 10 times higher than seen during past floods, with previously peaks around 500 NTU and 4m river height.  

Unfortunately, Wallaby Creek was not gauged during Cyclone Jasper when 2970 mm of rain fell in that catchment area. But the extent of the flood damage and high sediment loads from debris flows has instigated the installation of a new CYWP turbidity gauge site and water quality monitoring project starting in early January, which will monitor the recovery of the creek over the coming years.  

The upper Annan River gauge site at Shipton’s Flat, located upstream of the Wallaby confluence, was much less impacted by debris flows and bank erosion than Wallaby Creek, with 1300 mm of rainfall recorded at Collingwood mine. The river at Shipton’s Flat peaked at 8.3 m, which was well above the previous 5.7 m peak recorded at the site in 2019. Turbidity values peaked around 1600 NTU, which were similar to the previous wet season in 2023, but double that of the drier 2022 wet season. The rehabilitation efforts by QDNRME at Collingwood mine during 2023 performed very well during the extreme rainfall. However ongoing surface and batter rill erosion is continuing to contribute continuous turbidity values between 1000 and 4000 NTU into the decant dam creek and Annan River.  

Scrubby Creek is just upstream of the little Annan Bridge at Beesbike Station, and before Cyclone Jasper, it had been identified as the second dirtiest creek in the catchment with major gully and bank erosion. Past years turbidity values peaked between 1000 and 3000 NTU, with maximum turbidity recorded after fires burnt most of the catchment in 2021. However, during Cyclone Jasper, when 1200 mm of rain fell in the Scrubby catchment, turbidity values were 1000 NTU or less during the first flush. Values declined to around 500 NTU after Annan River floodwater backed up Scrubby Creek and diluted sediment concentrations.  

The Oaky Creek catchment received approximately 1200 mm of rain in six days and is the largest and previously dirtiest tributary to the Annan River, with major gully and bank erosion. Oaky peaked at 12.8 m and 800 cubic metres per second, higher than observed by locals in 30 years. Turbidity values were < 1000 NTU, lower than previous year’s first-flush due to major floodwater dilution, despite the catchment being partially burnt in December. However, the suspended sediment loads were substantial, with 36,000 tonnes transported during the event by 172 GL (billion litres) of floodwater.  

Preliminary data indicate that the Annan River estuary was three times dirtier than has been recorded during previous floods. Turbidity peaked at 2000 NTU at the Big Annan Bridge with water velocities at 2.5 m/s and a water height of 7 m, which was 1.5 m over the new bridge road surface. That means extremely high levels of sediment dumped on the seagrass meadows at Walker Bay, and Dawson and Forrester Reefs where gauges record turbidity and chlorophyll. By 24 –December,  satellite images recorded brown and green floodwater from the Daintree, Bloomfield and Annan Rivers reaching the outer reef from Cairns to Lizard Island.  

The water quality implications from the extreme floods are that a new sediment regime has been forced upon Wet Topics catchments including the Annan River. Past hotspots of erosion like Oaky Creek and Scrubby creek are continuing to erode, mainly from gully and bank erosion in dispersive soils. Meanwhile new hotspots such as Wallaby and Trevethan Creek now have elevated coarse and fine sediment loads from mass wasting (landslides), bank erosion, and re-erosion of floodplain sedimentation, These elevated sediment loads could take years to decline to previous conditions. A sediment geochemical tracing study, with samples collected from the Annan tributaries and estuary before, during and after the flood event will help document shifts in the sources of sediment supplied to the river and coast.  

Figure 1: Turbidity and river height (stage) at Trevathan Creek over the Cyclone Jasper flood event (source: CYWP ECYWQP Monitoring Project)  

Figure 2: Turbidity and river height (stage) at Oaky Creek over the Cyclone Jasper flood event (source: CYWP ECYWQP Monitoring Project)  

Figure 3: Turbidity and river height (stage) at Shiptons Flat over the Cyclone Jasper flood event (source: CYWP ECYWQP Monitoring Project)  

Figure 4: Turbidity, river height (stage), and velocity at Annan river estuary over the Cyclone Jasper flood event (source: CYWP ECYWQP Monitoring Project)  

Biblical flooding at Kings Plains

South Endeavour Trust

At first, we welcomed Cyclone Jasper with open arms. After nine relentless weeks of fire fighting, day after day, exhausting night after exhausting night, the cyclone had finally put the remaining fire fronts out.  But our joy was short-lived.


As the rain turned to a deluge that went on and on, the wetland system at Kings Plains started filling up with water and kept getting deeper and deeper.  And it rose… and it rose.  The wildlife was starting to concentrate around the house, in particular snakes.  At one stage one swam between John’s legs.

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The water started creeping in under the homestead at Kings Plains and everything was put up on tables and benches.  And still the water rose.  By the time it was waist deep through the ground floor of the homestead, John and Jan were wading through it to move critical things upstairs.  But what to save?  The computers, our files, anything of value.  And still the water rose.


By this time the rain gauge had gone under water.  We had already had 1.5 metres of rain and it was still pouring but we had no way to measure how much.


By 1am on what will forever be called flood night, the water downstairs was neck deep and rising fast.  The the second house was going under, the sheds had gone under, the new dongas were going under, the old dongas were done.  Fearing that the water would overwhelm the homestead, John and Jan made the decision to evacuate.


But easier said than done.  It was the middle of the night and still pouring rain.  The only option was to swim through the dark to the boat that was already floating in the shed.  It was a very scary moment but they made it.


Fortunately John had moved the vehicles to the highest ground on the hill behind the homestead, and his ute had their camper on the tray so they had somewhere to stay


By next morning the water was lapping at the upstairs of the homestead.  The hill was an island in the midst of a vast inland sea. The only means of transport was the boat.  But with the engine having gone under the only  means of propulsion was rowing.  Rowing back to the homestead John spotted a double reel QuikSpray unit floating by.  He tied it to a tree.  Our amphibious Argo had floated out of its shed and was gone.  It was later found washed up against a tree.  The hill was also refuge to all sorts of wildlife.  So much that it was hard to pull the boat up without disturbing them.  Not wanting to run over a snake John tried to move it.  Yes, it bit him.  Snake bandage applied, snake identified, expert advice was urgently sought: “venomous but not deadly, hospitalization not required”.


A rescue helicopter was dispatched, but still fearing that the upstairs of the homestead would go under John and Jan opted to stay and put everything in the upstairs as high as possible.  Fortunately the water peaked just a few centimetres below the upstairs floor.


This flood was so far above anything that had been experienced at Kings Plains in over 100 years that it seemed to defy explanation. But talking with the Christiansen family who had lived there from the 1920s to the 1980s it became clear that the issue was that both the Annan and the Normanby were experiencing record floods.  Not only did the water falling on Kings Plains have nowhere to go due to the rivers being so high, but water from both river catchments was flowing into the Kings Plains wetland system. 


Basically we had a lake that stretched right over the divide between the two rivers.  A lake 20km long, an average of 4km wide and probably up to 10m deep in places.


For anyone contemplating swimming in the Annan above the gorge, please be aware that Kings Plains has lots of salties and all of them have had a clear run to the Upper Annan!


With the drainage in both directions blocked by flooded rivers, it took days for the water around the Kings Plains homestead  to fall.  When it finally did, it revealed a scene of utter devastation, but with one piece of fascinating good news.  There was almost no mud at all.  There was a very thin dusting of fine sediment but otherwise it was an incredibly clean flood.  Not sure just what that means for our water quality work, but it was truly remarkable.

John rowing to work

Flood chaos in the homestead, but no mud!

Debris flows directly onto fringing reef to north of Cedar Bay (Landslide photos and maps by Jeff Shellberg)

Mass wasting (landslides) in the northern Wet Tropics during Cyclone Jasper

Widespread mass wasting was triggered by major rainfall during Cyclone Jasper across the northern Wet Tropics of Queensland. Mass wasting includes both shallow and deep-seated landslides into bedrock, and faster moving debris flows that deliver water-laden soil, rock, and trees down hollows and creeks. Local residents in Trevethan Creek, Cedar Bay, Helenvale and Rossville could hear the mountain rock crashing down during the early morning hours of the 18 December with one Cedar Bay camper describing the noise as “terrifying” as they scrambled to find stable higher ground away from flood water.  

Rainfall measurements over the six day storm totaled 2970 mm at upper Rossville in the Annan catchment (Lloyd data), 1962 mm in the upper Daintree, and >1439 mm at Bloomfield (missing 19-20 December). No rainfall gauges are located on higher peaks, which would have received much more. Lower elevation sites in the Annan Catchment received less rainfall, with 1254 mm at lower Shiptons Flat, 1149 mm at Beesbike Station, and 1034 at Oaky Creek, still impressive in their own right. However, it was the extreme rainfall total of 1440 mm recorded at Rossville from 17 December through to early 18 December, on top of the 885 mm of rain that fell earlier in the event, that triggered the mass wasting. 

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The scale of mass wasting observed was unprecedented in the historic record of knowledge and evidence in the northern Wet Tropics (Annan and Bloomfield catchments). Weathered rock, soil, and organic material built up in headwater hollows over the past century and were released during this event as debris flows, after the stability thresholds were passed. Estimating the associated rainfall and flood magnitude-intensity-frequency will take more analysis of existing and reconstructed data. Rather than a “one in 100 year or one in 200 year event”, a more accurate description is 1% or 0.5% exceedance probability that a given magnitude event or larger will occur in a given year. The probability resets each year, and large events could occur back-to-back or even within the same year. The probability of extreme rainfall is further altered by a warming and changing climate. 

Cape York Water Partnership has been surveying and photographing the extent of mass wasting in the northen Wet Tropics by ground, boat, drone, plane and satellite images since Cyclone Jasper passed. There are literally thousands of large landslides, small landslips, and debris flow scars across the landscape, with the large ones easily visible from roads and towns. The bulk of the landslides and debris flows have been within 10 km of the coast in steep forested terrain underlain by weathered meta-sedimentary rock of Hodgkinson Formation; however landslides into granitic terrain also occurred. The density mass wasting sites declined to the west as both rainfall and geology changed, with the upper Annan catchment west of Mt Finnagan much less impacted.  

Hotspots of mass wasting occurred in the headwaters of Trevethan Creek at Mt Amos, Wallaby Creek and Cedar Bay at Mt Hartley, Gap Creek between Mt Finnagan and Mt Finlay, and Mungumby Creek at the Big Tableland. Preliminary satellite images indicate upper Woobadda Creek above Degarra on the Bloomfield was heavily impacted by many landslides, as was much of the coastal strip around Wujal Wujal. It will take several weeks of clear weather to view and map all of the mass wasting via satellite images. Some preliminary examples are provided below.  

The water quality implications are that a new sediment regime has been forced upon Wet Topics catchments like the Annan River. Past hotspots of erosion like Oaky Creek and Scrubby creek are continuing to erode, mainly from gully and bank erosion into dispersive soils. Meanwhile new hotspots such as Wallaby and Trevethan Creek have elevated coarse and fine sediment loads from mass wasting, riparian bank erosion, and floodplain sedimentation, that could take a decade to decline to previous conditions. This means dirtier water and more sediment flowing to the reef for years to come. 

Gap Creek debris flows between Mt Finnagan and Mt Finlay

Gap Creek debris flows between Mt Finnagan and Mt Finlay

Cedar Bay landslide by air

Cedar Bay landslide from the ground (note person for scale)

Wallaby Creek headwaters at Mt Hartley  

Satellite images of Trevethan Creek debris flow paths off Mt Amos before Cyclone Jasper 

Satellite images of Trevethan Creek debris flow paths off Mt Amos after Cyclone Jasper 

Coral loss after Cyclone Jasper

CYWP scientists have observed coral bleaching on reefs in the inshore zone of the Great Barrier Reef to the north and south of Cooktown. 


Recent bleaching (bright white) and death (brown/green) has been observed at Gubbins Reef off the coast from the Bloomfield River, Dawson Reef near the Annan River mouth, and at Petheridge Isles near the Starcke River. All of these sites had numerous corals that were either in the early stage of bleaching (Gubbins Reef and Petheridge) or recently dead (Dawson Reef).

Left: Coral death and algal growth at Dawson Reef following cyclone Jasper (Photos left and below: Jeff Shellberg)

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The bleaching is likely caused by the extreme volumes of freshwater discharged from adjacent rivers in December. There have also been reports of bleaching further south of the Cape York region – (see ABC article). Coral bleaching occurs when corals are too stressed by high temperatures or low salinity water, such as freshwater flood plumes. Algae that live within the coral cells- and give them their colour- are ejected from the coral- leading to the bright white “bleaching” effect.


Corals can recover from bleaching if the water quality returns to normal range quickly enough. However, bleaching can also lead to coral mortality.


Dawson Reef is 6 km from the Annan river mouth. Since low salinity floodwaters inundated Dawson Reef for 15 days after Cyclone Jasper, the CYWP has observed coral bleaching and mortality of corals that were healthy in November 2023, before cyclone Jasper. Increased amounts of land-based nutrients washed out in floodwaters can also encourage algal growth (see photo above), which grows over the stressed or dead corals and impedes possible reef recovery.

Gubbins Reef January 2024

   Dawson Reef before          29 November 2023

      Dawson Reef after       23 January 2024

Dawson Reef before 29 November 2023 

Dawson Reef after 23 January 2024

A wild, wildfire season on Cape York in 2023

South Cape York Catchments Fire Project

With the recent rains and devastating floods, it's hard to recall we had serious bushfires in late 2023.

Things really heated up after completing our early dry season burns, and late dry season fires had devastating effects on our region. This was primarily due to arson attacks and accidental fires, combined with extremely dry fuel loads and windy weather conditions.

Main photo: Daarrba protection burn; Below top left: Operation Luther Agency collaboration; Below bottom left: Juunjuwarra mosaic burns; Below right: Ranger navigating over the control burns.

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Thankfully our project partners escaped the worst of it due to their extensive early dry season fire management activities. In the Jeannie, Starcke and McIvor river catchments we increased the amount of early dry season burns, with our Traditional Owner partners, to combat regular roadside arson attacks. We recorded a reduction in late dry season fires from 10,500 ha in 2022 to 3,000 ha in 2023. This strategy has proven to be effective in preventing late dry season fires from impacting large areas of Juunjuwarra, Ngulun and Daarrba traditional homelands.

In the Annan catchment a combined effort from local and regional fire brigades, government agencies, Cook Shire Council and landowners achieved a great result in preventing late dry season fires, as well as significantly improving public safety for small landowners adjoining our project area. With the support of the SCYC fire project and other stakeholders, Queensland Fire and Emergency Service conducted Operation Luther to reduce fuel loads before the late dry season. Over the course of two days, 35 personnel operating 18 fire fighting vehicles completed 1,300 ha of early dry season burns around Keating’s Lagoon Conservation Park, Cook Shire Council bore fields and the Marton reserve.

All of these on ground operations take considerate planning prior to the season to achieve the desired results. Now with the wet season we can look back at what worked well, and what didn’t work so well, and incorporate any changes into our plans for the 2024 early dry season. 

The serious wild fires in 2023 give us an important reminder to remain vigilant throughout our dry seasons, take notice of any fire bans and report any suspicious behaviour to the police.

Erosion control at stream crossings on Council’s unsealed roads for flood resilience

SCYC Council Roads Project

South Cape York Catchments, in partnership with Cook Shire Council, is working to trial erosion control Best Management Practices (BMPs) on unsealed Council roads. The emphasis is on practices that will reduce the fine sediment lost from road verges, batters, drains, and gullies in areas with fragile soils near creek crossings. Below we discuss the stream crossing BMP trials, while the next article focuses on managing gully erosion initiated by roads.

Scour erosion occurs at stream crossings when floods and vehicles erode the creek bed and road base sediments. These sediments are transported downstream, degrading water quality in the rivers and coastal waters. During May and June 2023, two stream crossings of Oaky Creek Road were upgraded with either concrete or rock crossings to reduce erosion. The crossing upgrades have also improved road drivability for the user.  

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Installing temporary diversion tracks around causeway work sites and through creeks often increases disturbance, erosion and weed spread. This is especially the case when funding is not available for erosion control and rehabilitation.  

During construction of the concrete floodway for the SCYC trial, the concrete slab was poured in two halves - side by side, one at a time. This allowed for an alternative driving lane on either side of the causeway work-site and reduced the erosion and weeds infestations associated with diversion tracks. 
While the construction time increased due to the two concrete pours and there were some extra costs such as traffic control lights, the additional cost and time was offset by the reduced costs of not building and rehabilitating a diversion track. The costs of reduced pollution to the Great Barrier Reef have not been factored into unsealed road construction and maintenance until now.  

Additionally, in November 2023 a 500 m section of gravel road at a stream crossing was sealed with a two-coat bitumen “dust seal” after a maintenance grade on the running surface (batters and drains were left ungraded). Dust seals can be applied to low traffic volume roads that are generally well-drained already and where major road alignments are not justified. For roads with a bitumen dust seal, maintenance costs are reduced in the long run, with benefits to the community (dust and vehicle wear) and environment (sediment erosion and reef pollution reduction). By bitumen sealing the road, annual grading of the batters and drains is reduced, and with additional cut-bank and gully erosion control at hotspots, sediment loads to the GBR are dramatically reduced.  

Road segment erosion control treatments continued in December 2023, as did ongoing terrestrial laser scanning (LiDAR) with ± 2 mm accuracy. This before and after scanning will help to quantify the reduction in erosion and fine sediment delivered to the Great Barrier Reef Lagoon from the road segments with different erosion control treatments

Cyclone Jasper dumped 1100 mm of rain in six days on Oaky Creek Road, and the bitumen seal and concrete causeways held up well with a noticeable reduction in erosion in treatment areas.  

The Council Roads Project with South Cape York Catchments is part of the Eastern Cape York Water Quality Program, funded by the partnership between the Australian Government’s Reef Trust and the Great Barrier Reef Foundation. 

Above: Installation of a concrete causeway poured in two halves.  

Above: Completion of a concrete causeway with minimal disturbance. 

Above: Unsealed road before treatment. 

Above: Road sealed with a bitumen "dust seal" for cost-effective erosion control. 

Road Gullies: A legacy issue along Cape York Peninsula roads 

South Cape York Catchments Council Roads Project

Across Cape York Peninsula, traditional road building and maintenance practices have initiated and accelerated gully erosion along all types of roads and tracks, including Cook Shire Council unsealed roads. Dispersive sodic soils are present across the region. These fragile soils erode easily during rainfall and are transported downstream by stream networks, with up to 90% of fine sediments eventually entering the Great Barrier Reef lagoon. These fine sediments settle on seagrass beds and coral reefs, impacting the health of these important ecosystems.  

Gully initiation is often caused by road drainage concentrating excess water onto steeper slopes. Alternatively, direct machine disturbance at cutoff drain outlets can destabilise slopes and lead to gullying. Most often these gullies are left to grow without any corrective intervention. Gully control outside the immediate road running surface is not funded by regular annual maintenance by Queensland Councils or by the State Government under the Disaster Recovery Funding Agreements (DRFA). Large scale erosion control typically falls in the “betterment” funding category, and only if the gully erosion immediately threatens the road infrastructure. Generally, the environmental cost of road gully erosion is externalised to the Great Barrier Reef Lagoon. 

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South Cape York Catchments and Cook Shire Council are working together to manage erosion and sediment runoff to the reef. In October 2023, South Cape York Catchments, in partnership with Cook Shire Council, conducted a large gully erosion control project along Oaky Creek Road. The project goals were to demonstrate the costs and techniques required to control legacy road gullies to guide future Federal, State and local funding of Shire road networks.  

A 0.3 ha and 5 m deep gully was reshaped, compacted, and capped with rock mulch on batters and coarse rock on top of geofabric along rock chute flow paths. 800 tonne of rock was used. The gully was eroding 250 tonnes / year of sediment between 2020 and 2023. Gully control costs were $130,000 and the project saved 116 tonnes of fine sediment (< 20um) to the GBR at a cost effectiveness of $1100 per tonne of fines.  

Cyclone Jasper in December 2023 was a significant test of the gully treatment, with 1100 mm of rainfall in 6 days. The rock chute and batters resisted erosion well, with only a few minor movements of rock. The effectiveness of the rock treatment was ~ 95%, well above comparable gully treatments with organic capping and grass in the same catchment that faired much worse during Cyclone Jasper.  

The Council Roads Project is part of the Eastern Cape York Water Quality Program, funded by the partnership between the Australian Government’s Reef Trust and the Great Barrier Reef Foundation. 

Before erosion control at site 8 road drain and gully, along Oaky Creek Road

After erosion control at site 8 road drain and gully, along Oaky Creek Road

Before erosion control at site 8 road drain and gully, along Oaky Creek Road

After erosion control at site 8 road drain and gully, along Oaky Creek Road

Powerline track erosion control with Ergon and Jabalbina Partners

CYWP together with Ergon Energy completed a cost-share erosion control project in October and November 2023. The unique partnership aimed to complete civil works along a 10 kilometre powerline track which would reduce sediment runoff to local creeks and the Great Barrier Reef, stop significant track and gully erosion, and provide long term resilience for track access. 

Located between Black Mountain Kalkajaka and Trevethan Waterfall near Mt Amos, the 43 year old track traverses four private Freehold properties, two sections of Black Mountain Kalkajaka National Park and Jabalbina Yalanji Aboriginal Corporation (JYAC) freehold land. 

Left: Terrestrial Laser Scanning of powerline track sites 17, 18 and 19

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Working closely with Traditional Owners for cultural heritage clearance, Ergon’s local civil contractors completed works on 33 sites over a four week period. With support from CYWP staff in planning, design and site management, the participants used over 2000 tonnes of rock and gravel to create a variety of erosion control measures which included: 

                 46 Whoaboys (to divert track water runoff) 

                 18 Check dams (for reducing water runoff velocity in gullies)  

                 917 m2 of Rock Sheeting at 17 sites (to prevent track erosion) 

                 300 m2 of Rock Armouring at 29 sites (to reduce creek/gully erosion) .

CYWP Primitive Tracks Project Manager Dr Jeff Shellberg said that the Ergon Trevethan Project was a great example of private and public partnership investment to reduce erosion in GBR catchments, fixing past legacy issues along powerlines, and providing resilient access to power poles for maintenance.

Cyclone Jasper in December 2023 was a significant test of the treatment works, with 1200 mm of local rainfall in five days. After Trevethan and Wallaby Creek destruction from flooding, CYWP Tracks Project Officer Brad Smith said said he was pleasantly surprised that the Trevethan powerline mostly held up from all the hard work, especially all the whoaboys. 

"Out of the 46 whoaboys, only one failed, while five had major erosion and 40 were functionally stable with minor to modest erosion. The creek crossings had more erosion due to the flood impacts, with 19 of the 29 crossings with major erosion of placed rock. In contrast only a few check dams moved in gully drains," Brad said.

Before and after pictures are included below.  

Monitoring using Terrestrial Lase Scanning (TLS) was conducted at a control and treatment segment before the cyclone. Scanning after the wet season will help quantify erosion rates and treatment success.  

As with many erosion control structures after record rainfall and cyclone, some maintenance will be required during the next dry season to enhance long-term resilience.  

Above: Before

Above: After

Above: Before

Above: After

Above: Before

Above: After

Above: Before

Above: After

Future resilience to extreme rainfall and flooding  

By Dr. Jeff Shellberg, Cape York Water Partnership  

Since the devastating December floods, Cape York Water Partnership have been working to assess water quality and flood impacts in the Annan and other river catchments, and consider ways our communities can be better prepared for future extreme flooding. 


While the observed slowdown of cyclone Jasper was not initially forecast by weather models, BOM continuously updated the forecasts for prolonged heavy rain. But the models did not predict the magnitude of the six-day rainfall event in the higher ranges of the northern Wet Tropics. Over 2970 mm of rainfall fell at Rossville (Lloyd data) during cyclone Jasper, with 885 mm falling between 13-16 December, 1440 mm on 17-18 December and 665 mm on 19 December. More rain likely fell higher in the ranges. The Annan River at Beesbike rose to flood stage at six metres on 17 December at 7:00 am, rose another five metres in 15 hours to a record 11.2 m at 10.00pm when major damage began, and then rose another two metres over night to peak at 13.3 m, with this historic flood damaging property and threatening lives.   

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People living on floodplains know they are prone to flooding and prepare accordingly, but predictions of flood height risks for extreme events like these are lacking. Improved rainfall-runoff modeling using high-resolution topography maps (LiDAR) could better assign risks to individual floodplain pockets or properties. LiDAR topography data exist for many of the flood-affected communities south of Cooktown. These areas should be re-flown post-flood to document flood impacts and assess future flood risks. Tide and flood interactions in estuaries could also be better modelled, as could predicted changes with future sea level rise.  


Real time warnings of approaching floodwater could be improved. Queensland Government flood height gauges on the Bloomfield and Annan River were damaged by the extreme floods, but still provided some warning of rising river levels for the area. What was missing was real-time rainfall observations in higher elevation areas above the communities of Rossville and Wujal Wujal. The installation of a rainfall gauge at upper Gap Creek above Rossville could help warn residents of potential floodwater heights and timing. But mobile phone and internet service which is needed to access real time data is currently unreliable. 


Opening blocked roads from landslides and bank erosion is a priority for local Councils, TMR, and community. However, rebuilding back to the same conditions keeps the community vulnerable to future failures. QRA and DRFA disaster recovery guidelines focus on repairing unsealed and sealed roads back to their pre-disaster conditions. Instead of re-building past roads to their pre-disaster conditions, incorporating improved erosion control following Best Management Practices (BMPs) will make roads more resilient for residents and reduce anthropogenic sediment loads to the Great Barrier Reef Lagoon. Examples include using more drainage relief culverts, additional causeways and creek bridges, rock armouring of batters and steep slopes, stabilizing road-caused gullies and landslips, minimizing annual vegetation disturbance, revegetation of bare areas, and sealing gravel roads on unstable soils.  


While no one foresaw the devastation to follow cyclone Jasper, investing in these resilience measures can help our communities be better prepared for future flooding, and improve the health of our local waterways.

Main photo: Wallaby Creek floodplain, after Cyclone Jasper

Above: Gap Creek and adjacent Road showing loss of riparian zone and destruction of the road by flood debris flows

Above: Wallaby Floodplain LiDAR in 2013 showing elevation and relative flood risk

Above: Common need for drainage relief culverts along local Council roads.  

Bev Coleman, finance officer extraordinaire

Meet the CYWP team!

In less than three years, Cape York Water Partnership has expanded from an informal alliance of people and organisations, to an incorporated association with a four-person management committee, nine staff, and three long-term contractors. In this part of the world, where finding the right people for a science-based organization can be difficult, we are blessed with a dedicated and experienced team.  

Our diverse backgrounds include hydrologist/ fluvial geomorphologist, ranger, aquatic scientist/marine biologist, zoologist, ecologist, environmental scientist, engineer, builder, farmer, storyteller and more. Over half our team were born and raised in Cape York, bringing a deep understanding of the place and its people. The rest of us have been captured by the magic of the Peninsula and made it our home.  

Above left: CYWP Staff from left to right are: Eric Dick (Water Quality Project Officer), Barb Rosendale (Program Management Support Officer), Dr. Jeffery Shellberg (Track Erosion and Sediment Loads Project Manager), Sarah Herkess (Program Coordinator), Lyndal Scobell (Comms advisor), Ori Albert Mitchell (Track Project Officer and GIS whiz), Dr. Christina Howley (Program Director and Aquatic Ecosystems Monitoring Project Manager)   

Above: Robert Morris (Track Erosion surveyor) and Brodie Gibson (former WQ project officer) in the background.

Above: Sienna Thomason (CYWP water quality intern) 

Above: Brad Smith (Track Erosion Project Officer) 

Welcome to our new management committee

Cape York Water Partnership

We have recently elected a new Management Committee and would like to express our gratitude to departing committee members, Kallum Clarke (Jabalbina Yalanji Aboriginal Corporation) and Priscilla Gibson (Rinyirru Aboriginal Corporation). Kallum and Priscilla, along with Christina as Secretary and Treasurer Sue Marsh (Laura Rangers) have guided us through the challenging set-up stage and helped to create a strong governance foundation for CYWP. We are excited to welcome our wonderful new committee members- Alberta Hornsby (Chair) and Gary Meredith (Deputy Chair).

Above left:  Our new management committee. From left - Gary Meredith (Deputy Chair), Alberta Hornsby (Chair), Christina Howley (Secretary) and Sue Marsh (Treasurer).

Right: The outgoing committee, from left - Kallum Clarke , Priscilla Gibson, Christina Howley and Sue Marsh.


The Eastern Cape York Water Quality Program is funded by the partnership between the Australian Government’s Reef Trust and the Great Barrier Reef Foundation.