Plane Catchment Story - Subcatchment key messages

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• Overview
• Physical features
• Natural values
• Subcatchment key messages
• Sandy subcatchment
• Sandringham Lagoon subcatchment
• Rocky Dam Creek subcatchment
• Acknowledgements

View the Plane catchment story

Transcript

Subcatchment key messages

The Plane catchment is listed as a single catchment but consists of several coastal subcatchments with different characteristics in terms of geology, vegetation and land use. Sandy Creek is the largest subcatchment and is dominated by cane farming. Rocky Dam Creek is also relatively large and supports cattle grazing and cane farming. 

Main image. Sandy shore of Marion Creek with exposed rock and mangroves, Notch Point - provided by Reef Catchments.

Table of contents

1. The subcatchments
2. Sandy subcatchment 
3. Plane subcatchment
4. Rocky Dam subcatchment
5. Cape subcatchment
6. Marion and West Hill subcatchments 
7. Carmila, Flaggy Rock and Oaky subcatchments

The subcatchments

A 'catchment' is an area with a natural boundary (for example ridges, hills or mountains) where all surface water drains to a common channel to form rivers or creeks.* 

The Plane catchment is listed as a single catchment but consists of several distinct areas (subcatchments), which have similar characteristics:

1. Sandy subcatchment (Bakers Creek, Ross Creek, Okay Creek, Sandy Creek, BL Creek, Bell Creek, Alligator Creek, Splitters Creek, Louisa Creek)
2. Plane subcatchment (Plane Creek)
3. Rocky Dam subcatchment (Willy Creek, Tommy Creek, Rubicon Creek, Plumtree Creek, Duff Creek, Station Creek, Cherry Tree Creek, Coalters Creek, Tedlands Creek, Turnor Creek, Lantana Creek, Cattle Creek, Arrowroot Creek, Devil Flat Creek, Green Swamp Creek, Rocky Dam Creek, Dawson Creek) 
4. Cape subcatchment (Daintry Creek, Cape Creek)
5. Marion and West Hill subcatchments (Plantation Creek, Emu Creek, Marion Creek, Frog Creek, Basin Creek, Gillinbin Creek, West Hill Creek, Oaky Creek, Spider Creek, Three Mile Creek, Bone Creek, Blind Creek)
6. Carmila, Flaggy Rock and Oaky subcatchments (Leichhardt Creek, Prendergast Creek, Mccafferty Creek, Hannah Creek, Carmilla Creek, Feather Creek, Blind Creek, Stony Creek, Wheybush Creek, Flaggy Rock Creek, Stockyard Creek, Lantana Creek, Okay Creek, Turners Hut Creek, Mosquito Creek, Sandfly Creek, Middle Creek)

Main Image. Lake Barfield near Hay Point - provided by Saskia von Fahland.

*Definition sourced from the City of Gold Coast website - see links at the end of this map journal.

Sandy subcatchment

See the 'Sandy subcatchment' tab for a more detailed discussion of this subcatchment. An overview of the key message for the Sandy subcatchment are provided below.

• Small section of granites in headwaters of Sandy Creek, but mainly alluvium and metamorphics, with coastal clays, mud and sand near the coast.
• Low elevation with some hill slopes in the headwaters and high rainfall over the headwaters.
• Channels tend to be narrow in the upper parts but widen out to the coast and estuarine systems.
• Large areas of deep alluvium along the coastline with good transmissivity (ability for water to pass through the sediment).
• Water is diverted from Mirani Weir to Kinchant Dam, which is located on Sandy Creek’s north arm. 
• Kinchant Dam releases water for irrigation purposes via the Oakenden Main Channel, and flood releases may be made from the dam into Sandy Creek during high rainfall events.
• Modified landscape with large areas of sugar cane cropping and some grazing.
• High value freshwater wetlands (i.e. Sandringham and De Moleyn's lagoons).
• Three distinct areas include Bakers Creek, Sandy Creek and Alligator Creek (Splitters Creek, Bell Creek), as discussed on the 'Sandy Creek subcatchment' slide.

Main image. McEwans Beach - provided by Reef Catchments.

Plane subcatchment

• The Plane subcatchment headwaters are hard siltstone and mudstone, volcanilithic sandstone and conglomerate, with a fault line along the coast.
• The alluvial floodplain consists of clay, silt, sand and gravel channel, with muds and sands near the coast.
• The headwaters are up to 240 metres above sea level (ASL), with higher rainfall over the upper parts and fast run off particularly where it is steep.
• There are groundwater dependent ecosystems (GDEs) associated with some local fractured rock aquifers, however there are limited alluvial aquifers.
• Blue green algae blooms can occur in Middle Creek Dam.
• Plane Creek has extensive salt marsh and salt flats east of Sarina.
• Plane Creek has a series of small weirs that regulate flow and streams tend to be less regulated and modified in the southern parts.
• There are large drops on some of the weirs on Plane Creek, which can interfere with fish passage.
• There is a sugar mill on Plane Creek at Sarina.
• There is a sewage treatment plant (STP) for Sarina.
• Water supply to the Sarina Township is from Middle Creek Dam.

Main image. Middle Creek Dam, upper Plane subcatchment - provided by Reef Catchments.

Rocky Dam subcatchment

See the 'Rocky Dam Creek subcatchment' tab for a more detailed discussion of this subcatchment. An overview of the key message for the Rocky Dam Creek subcatchment are provided below.

• The geology is dominated by alluvial deposits on the floodplains, including clays, silts and sands.
• The upper catchment is bound by intrusive granites and volcanic formations which make up the Connors Range (felsites and mafites, volcanilithic sandstone and fine-grained Mountain View volcanics).
• The lower catchment is underlain by estuarine deposits and unconsolidated sediments.
• Mean rainfall of 1,507 millimetres per year in Koumala.
• The estuary channel meanders and has high banks.
• The floodplain has areas of good remnant rainforest and accumulates sediment.
• Cab and Tedlands creeks include large ponded pastures, which are bunded to exclude salt water.
• Boat wash can cause erosion in the estuary.
• Riparian vegetation is variable in terms of extent and condition.
• Several deep and permanent pools provide good fish habitat.
• Natural rock weir on main channel, east of the Bruce Highway, and another natural barrier on Waterfall Creek likely present impassable barriers for fish migration.

Main image. Freddy Creek, Oonooie - provided by Saskia von Fahland.

Cape subcatchment

• The headwaters of the Cape subcatchment are hard siltstone and mudstone.
• The lower catchment is dominated by mud, sandy mud, muddy sand and gravel, together with quartzose and shelly sand and beach ridges.
• The headwaters are 230 metres ASL down to 10 metres ASL on the coastal flats.
• Cape Creek has fast run off due to the steep slopes.
• Good riparian vegetation is protected in Cape Palmerston National Park.
• High value dugong and seagrass habitat and a declared FHA are located in coastal marine waters.
• Cape Palmerston served as an important meeting area for the Plane catchment's coastal and western tribes.

Water mouse - provided by Tina Ball, Queensland Parks and Wildlife Service.

Main image. Cape Palmerston headland looking north - provided by Tine Ball, Queensland Parks and Wildlife Service.

Marion and West Hill subcatchments

• The headwaters of the Marion and West Hill subcatchments are mixed mafites and felsites, and granites with Marion Creek on a fault line.
• The lower elevations are mostly siltstone and mudstone, sand and alluvium with estuarine deposits supratidal flats and coastal grasslands near the coast.
• Limited groundwater systems in very shallow alluvium.
• Dryland farming supplemented by irrigation dams.
• The Basin Creek area is mainly used for grazing but no large scale irrigation.
• Marion Creek has natural rock bars.
• Flow in Marion Creek is generally good.
• There are more permanent pools on Gillinbin Creek.
• Basin Creek has some large waterholes.
• There is some erosion associated with cleared riparian vegetation.
• West Hill Creek flow is near-permanent with freshwater wetlands in the alluvium, and limited groundwater systems in shallow alluvium.
• West Hill State Forest is located on the southern headland of West Hill Creek mouth, otherwise land use is mostly sugar cane and grazing.
• Cane irrigation water is sourced from off-stream farm dams (dryland cropping).
• Small areas of ponded pasture on Bund Creek.

Main image. Salt flat, West Hill Creek - provided by reef Catchments.

Carmila, Flaggy Rock and Oaky subcatchments

• The headwaters of the Carmila, Flaggy Rock and Oaky subcatchments are underlain by volcanics (granites), metamorphics, siltstone and mudstone.
• The lower parts are dominated by colluvium and other unconsolidated sediments.
• The headwaters are up to 470 metres ASL.
• Good water supply close to Carmila Creek with several shallow coastal aquifers.
• Carmila Beach residential area uses septic systems.
• Dugong and seagrass areas.
• Fast runoff from mostly hard geologies with some fractured rock providing for localised groundwater aquifers.
• Mostly seasonal flows although Flaggy Rock Creek tends to hold near-permanent water.
• Limited alluvium around Flaggy Rock Creek.
• Some erosion in parts of these subunits (e.g. Carmilla and Flaggy Rock creeks).

Carmilla Creek - provided by Reef Catchments.

Main image. Oaky Creek - provided by Reef Catchments.

Last updated: 18 November 2025