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Kolan catchment storyThe catchment stories use real maps that can be interrogated, zoomed in and moved to explore the area in more detail. They take users through multiple maps, images and videos to provide engaging, in-depth information. Quick facts
Quick linksView the Kolan catchment story TranscriptThis map story is part of a series prepared for the catchments of Queensland. We would like to respectfully acknowledge the First Nations peoples of the land and waters on which this project takes place, and Elders both past and present. We recognise the ongoing effort to protect and promote Aboriginal and Torres Strait Islander cultures, which will leave a lasting legacy for future Elders and leaders. Cover image. The Kolan River at Moorland, Photo by Gary Cranitch ©️Queensland Museum. Table of contents
Understanding how water flows in the catchmentTo effectively manage a catchment it is important to have a collective understanding of how the catchment works. This story map gathers information from experts and other data sources to provide that understanding. The information was gathered using the ‘walking the landscape’ process, where experts systematically worked through a catchment in a facilitated workshop, to incorporate diverse knowledge on the landscape features and processes, both natural and human. It focused on water flow and the key factors that affect water movement. The story map was prepared by the Queensland Wetlands Program in the Queensland Department of the Environment, Tourism, Science and Innovation in collaboration with local partners. The story map was prepared by the Queensland Wetlands Program in the Queensland Department of the Environment, Tourism, Science and Innovation in collaboration with local partners. Navigating this catchment storyThis catchment story contains several interactive elements. These features are designed to assist your viewing experience, so read on for tips on how to best use them.
Main image: Horticulture near Apple Tree Creek, photo by Gary Cranitch © Queensland Museum. Water movementThis catchment story describes the location, extent and values of the Kolan catchment. It demonstrates the key features which influence water flow, including geology, topography, rainfall and runoff, natural features, human modifications and land uses. Knowing how water moves in the landscape is fundamental to sustainably managing the catchment and the services it provides. Kolan catchmentThe Kolan catchment is located to the north of Bundaberg within the Burnett Mary Regional Group natural resource management area. It is mostly within the Bundaberg Regional Council area with small areas in the North Burnett and Gladstone regional council areas. The catchment covers approximately 2,905 square kilometres ( click for animation ). The catchment includes the Kolan River and its tributaries such as:
Kolan catchment waterways flow to the Great Sandy Marine Park, which has connections to the Ramsar-listed Great Sandy Strait and the Great Sandy Biosphere in the south, and flow to the Great Barrier Reef Coast Marine Park in the north. Great Sandy Biosphere Map The Kolan is a Great Barrier Reef catchment. Sediments, nutrients and pesticides from the catchment can enter the Great Barrier Reef lagoon during large floods with flow-on effects to flora and fauna including corals, seagrass, turtles and dugongs. The Great Barrier Reef is World Heritage-listed and a Commonwealth and State marine park. The Kolan catchment is adjacent to the Baffle , Boyne and Burnett catchments. There are hydrological connections within the coastal parts of these catchments through groundwater. Values of the catchment—EconomicA range of different land use types combine to make up the land uses 20 of the Kolan catchment. Land use is dominated by grazing on native pastures together with:
Horticulture is very important to the economy and communities of the Kolan catchment. It is supported by the rich, well-drained soils, groundwater supply and the Bundaberg Water Supply Scheme (BWSS). For more information, see the Wide Bay -Burnett Horticulture story. Other economic values include tourism and recreation with parts of the upper catchment popular for fresh-water kayaking and picnicking, and coastal parts used for boating and recreational fishing, with a rowing club located on the Kolan River. Australasian Darter, Anhinga novaehollandiae, Photo by Gary Cranitch © Queensland Museum Environmental and SocialThe Kolan catchment provides important habitat for many marine, freshwater, terrestrial and groundwater dependent species and includes several protected areas:
The wetlands of the catchment include:
Freshwater systems include:
Intertidal wetlands include trees (casuarinas and some melaleucas), grasses, herbs, sedges, mangroves, saltmarshes, salt pan, gravel, sand and mud, and are adjacent to subtidal wetlands such as rocky shores, coffee rock, boulders, gravel, sand and mud. Intertidal and subtidal ecosystems support threatened and migratory species, including marine turtle nesting. The wider Burnett-Mary region supports species of protected marine turtles , three of which regularly nest in the region. Intertidal systems also provide migratory shorebird roosting and feeding habitat notably for beach stone-curlew (Esacus neglectus), far eastern curlew (Numenius madagascariensis), bar-tailed godwit (Limosa lapponica), greater sand plover (Anarhynchus leschenaultii) and lesser sand plover (Charadrius mongolus). The nearby Great Sandy Strait is a Ramsar-listed internationally listed wetland. The catchment contains limited waterways with connected hydrology from fresh to brackish to salt water, (e.g. Yandaran Creek and waterways leading into the southern Kolan estuary ). These waterways are important fish habitats especially for diadromous fish that need to complete their life cycles by moving between fresh and salt water. The waters of the Great Barrier Reef, Hervey Bay and the Great Sandy Strait support iconic marine mammals such as humpback whales (Megaptera novaeangliae) and dugong (Dugong dugon). The catchment lies between the Hervey Bay-Tin Can Bay and Port of Gladstone-Rodds Bay dugong protection areas. Across Hervey Bay, the World heritage-listed K'gari (Fraser Island) supports a wide range of species and ecosystems and are important culturally and recreationally, including for tourism. The area supports a range of wetland types and values. Further information about some of the different types of wetlands across the catchments is provided below:
Geology and topographyThe geology of a catchment fundamentally affects how the water in the catchment flows both above and below the ground and is also critical for the formation of the soils in the catchment. Several different rock units underlie the geology of the Kolan catchment. Most of the catchment is relatively flat, however the headwaters of the rugged Many Peaks Range are 700 metres above sea level. The upper catchment is dominated by the old, hard sedimentary rocks of the Wandilla and Gympie Blocks, which were deposited more than 220 million years ago when the edge of the continent was still being constructed. The subsequent geological story of these rock units, from west to east, can be considered largely in three main phases:
The geological layers of the catchment are listed below from older (generally deepest layers) to younger (generally uppermost layers).
The mid catchment is dominated by the Maryborough Basin, a large depression from the sinking fault block that has filled with mainly sedimentary geologies. The Elliott escarpment is a slightly elevated plateau that spans the Kolan and Burnett coastal catchments and is formed by the Elliott Formation . It provides for a very productive groundwater system associated with the porous, well-drained Elliott Formation sediments which, together with the free-draining soils and BWSS, provides the ideal conditions for intensive horticulture (mixed crops and tree crops) and sugar cane cropping. See the Wide Bay-Burnett Horticulture Story for further information. The Elliott Formation was deposited as sediments 65 million years ago and subsequently weathered by heavy seasonal rainfall ( see diagram ). There are several volcanics outcrops near Gin Gin and Lake Monduran . The Fred Haig Dam wall is constructed around these hard volcanic outcrops at a natural constriction in the landscape. Upstream of Bucca weir, the main channel is forced northward through hard Maryborough Formation adjacent to alluvial terraces (older alluvium) and flats (younger) along the channel. Downstream of the Bucca weir, a fault line has exposed older geologies of the Maryborough Basin. The river is forced southward through another gorge of the Maryborough Formation onto wider alluvial terraces and flats. Relatively narrow alluvial flats have formed along the mid Kolan River upstream of Bucca weir. The lower catchment is mostly porous. It is dominated by wide alluvial flats , coastal sand dune systems, marine muds and the Elliott escarpment. The Elliott Formation forms the northern parts of the catchment. These geologies are porous and well-drained, which provides for the most important groundwater resource in the catchment and region, except where the surface has eroded away exposing harder ferricrete beneath. Below are the Fairymead beds formed over old river beds. The alluvial flats are part of a large floodplain that connects to the Burnett catchment. The sand dunes consist of older Pleistocene (700,000 to 10,000 years ago) sand that has been mostly levelled for farming. Seaward is a younger Holocene sand dune system (less than 10,000 years old) that runs parallel to the shoreline, but have been mostly flattened for farming and residential. Groundwater from the escarpment feed into the Kolan and Burnett catchment, via deep drainage and direct runoff, and also onto the coastal sand system. Folds and FaultsThere are many fault lines in the upper Kolan, and this fault system separates the old, hard upper geologies from that of the mid catchment. Two fault lines also run parallel to the river valley, joining in the Kolan estuary. Further information about some of the different types of geologies and aquifers is provided below:
Natural features - RainfallThe Kolan catchment has a subtropical climate with temperatures ranging from 10 to 33 degrees Celsius. The climate is hot and humid with a wet summer to autumn, with a drier winter and spring. Most rainfall is part of northern monsoons, cyclones or troughs in late summer to early autumn. Average annual rainfall ranges between 1,000 to 1,400 millimetres per year. Average rainfall is slightly higher in the west due to orographic uplift over the mountains and hills of the upper catchment. Orographic rainfall process, East (left), to West (right) Surface waterRainfall runs off rapidly from the hard, relatively steep upper catchment into creeks and eventually the Kolan River and Lake Monduran ( view animation* ). Lake Monduran is part of the Bundaberg Water Supply Scheme (BWSS) with water transferred from the Kolan to the Burnett (Paradise Dam, Ned Churchward Weir and Ben Anderson Barrage) and Burrum (Isis area channel and pipeline network) catchments. See the Wide Bay-Burnett Horticulture Story for further details. Apart from flood flows, most freshwater remains within the Kolan River and in large impoundments , however, some water is transferred to farms in the Burnett and Burrum catchments. The Bucca Weir and Kolan Barrage can overtop following heavy rainfall. The Kolan Barrage contains a vertical slot fishway. Rainfall and surface water in creeks and impoundments also sinks into the ground where it supports a variety of ecosystems. The smaller channels and gullies eventually flatten out to form larger waterways that flow through lower lying land. They pass through unconsolidated sediments which store and release water, prolonging flow. Water is discharged very slowly from the groundwater aquifers (notably the Elliott Formation) into waterways, maintaining base flow. In areas dominated by surface flow, the hydrological seasonality associated with these wet and dry season flow conditions are important to the ecological character, function and associated values of aquatic ecosystems. The Kolan River passes through several gorges incised in the hard Maryborough Formation geologies. Downstream of Bucca Weir , the gorge and channel support a series of riffles containing ribbon weed (Vallisneria sp.). These systems provide habitat for a range of fauna such as sensitive macroinvertebrates; turtles, including Krefft’s river turtle (Emydura krefftii), broad shelled river turtle (Chelodina expansa) and eastern snake-necked turtle (Chelodina longicollis); and platypus (Ornithorhynchus anatinus). Water is released from Bucca Weir to support the riffle systems. Rainfall is important for waterways associated with the sand masses as it provides for groundwater recharge. Rainfall also recharges the Elliott Formation groundwater systems. Groundwater and aquifersThe upper catchment's older geologies are hard with rapid surface runoff, however there are many faults leading to fractured geologies that are capable of storing and releasing groundwater, but only in localised areas. Sediments of the Maryborough Basin in the middle of the catchment are porous, forming the Elliott (Cenozoic), Burrum (Cretaceous), Grahams Creek (Cretaceous) and Duckinwilla (Triassic to Jurassic) aquifers. Near-surface aquifers are recharged by heavy rainfall events, or from leaking surface waterbodies. The Elliott Formation Aquifer is an unconfined aquifer consisting mainly of deep sands, silt and conglomerate, including discrete beds of gravel. Where the Elliott Formation beds are horizontal (i.e., south of the main channel) there is a thick, productive aquifer with a hydraulic head running southwest to northeast. Recharge occurs at the top of the catchment, with discharge closer to the coast. The Elliott Formation Aquifer discharges into waterways and the intertidal area. North of the Kolan River, the Elliott Formation Aquifer is thin and heterogeneous and provides little groundwater potential. Faulting has created connectivity between the Elliott Formation Aquifer and Burrum Coal Measures beneath it. Groundwater recharges into the older aquifers (Burrum, Graham’s Creek) through rainfall where they outcrop along the western side of the Maryborough Basin, or through infiltration from the very porous Elliott Formation Aquifer above. The older aquifers are highly heterogeneous and less productive and fresh than the Elliott Formation Aquifer. The alluvial terraces and flats of the Kolan valley are also aquifers. The upper alluvial terraces are older (Pleistocene), representing a previous sea level, and more extensive lower alluvial flats are more recent (Holocene). Not all Maryborough Basin geologies are aquifers. The Maryborough Aquitard (Maryborough Formation) is a siltstone-dominated groundwater flow barrier between the Burrum and Grahams Creek aquifers. Fault lines and folds (anticlines and synclines) near Bucca Weir have exposed this aquitard on the surface, where it formed a barrier to surface flow and shifted the Kolan River to the north through a gorge Either side of the Kolan River mouth are sand dune systems, which receive recharge from rainfall and surface flows. Both Pleistocene and Holocene dunes are aquifers and support many freshwater wetlands. VegetationVegetation affects how water flows through the catchment, and this process is affected by land use and management practices. Vegetation slows water, retaining it longer in the landscape and recharging groundwater aquifers, and reducing the erosion potential and the loss of soil from the catchment. Development and human activities change the shape of the landscape and can modify water flow patterns. Several different vegetation types combine to make up the original native (preclearing) vegetation of the Kolan catchment. Large areas of remnant vegetation remain on the hilly upper catchment, however the valleys and most of the lower catchment are cleared. Explore the swipe map* showing vegetation clearing over time, using either of the options below.
The upper catchment supports subtropical dry rainforest with emergent hoop pines, gallery rainforest and drier eucalypt forests. Bulburin National Park preserves the largest stand of subtropical rainforest in central Queensland, together with New England blackbutts (Eucalyptus andrewsii) towards their northern range limits, a population of around 40 endemic macadamia trees (Macadamia jansenii), dry rainforest and emergent hoop pine. Limited riparian vegetation remains on the alluvial flats and main channel of the Kolan River. There is some river red gum (Eucalyptus tereticornis) open forest regrowth on the alluvial flats. The coastal Holocene dunes support connected palustrine and mangrove wetlands, and a patch of protected microphyll / notophyll vine forest. The protected Coxen’s fig parrot (Cyclopsitta diophthalma coxeni) has been sighted in this area. Palustrine melaleuca swamps and lakes form a remnant wetland complex along the dune-swale system between the Kolan mouth and Burnett delta, which is partially fragmented by Moore Park Beach. These wetlands are connected to the declared fish habitat area and to the salt waters west of Barubbra Island. Modified featuresChannels and infrastructureBuildings and important infrastructure such as roads , railways (zoom for more detail) and creek crossings create barriers and low permeability surfaces that redirect water through single points or culverts, leading to channelling of water. Relatively small parts of the catchment have been developed. Urbanisation around the township of Moore Park Beach has created some hardened surfaces (including roads), causing rainfall to run off as stormwater rather than infiltrating into the porous sand dunes. Roads impede water flow and aquatic fauna passage. Stormwater from hardened surfaces also enter drains at the bottom of swales between the dunes, and moves through to Moore Park Creek. Urbanisation along the Woongarra Coast and in Hervey Bay has hardened surfaces and rainfall runs off as stormwater, rather than infiltrating into the porous sand dunes and Hummock Basalt, and roads impede water flow and aquatic fauna passage. Dams and weirsThe main impoundments of the Kolan catchment are:
These storages influence how and when water flows through the catchment and to other catchments by inter-basin transfers. Fred Haigh Dam (Lake Monduran), Photo by Gary Cranitch © Queensland Museum The Kolan barrage limits the upstream tidal extent and is fitted with a vertical slot aquatic fauna passage structure (fishway). Other barriers impede aquatic fauna passage during baseflow conditions, with movement during flood conditions only. Irrigation canal, Gin Gin, Photo by Gary Cranitch © Queensland Museum Water Supply Scheme and irrigationA complex network of dams, weirs, channels and pipelines has been developed to support horticulture in the Kolan. Many form part of the Bundaberg Water Supply Scheme (BWSS) managed by Sunwater. This scheme provides water infrastructure to support irrigated horticulture and agriculture via inter-basin transfers between the Kolan (Fred Haigh Dam) and Burnett (Paradise Dam, Ned Churchward weir and Ben Anderson barrage) catchments. One of the benefits of the irrigation system was to provide surface water as an alternative to groundwater extraction close to the coast. Historically, groundwater extraction from coastal aquifers for irrigated horticulture and agriculture caused saltwater intrusion into the freshwater aquifer. By providing a surface water supply as an alternative to groundwater, groundwater depletion, and saltwater intrusion, was limited. Seawater intrusion was also limited by the introduction of groundwater management including:
A system of drainage canals has also been excavated into the dune system to the south of the Kolan River, to drain the high watertable, reduce waterlogged soil and grow sugar cane . Most of this area is below the level of highest astronomical tide and the floodgates are leaky, hence there is still some tidal flow and mangrove growth. See the Wide Bay-Burnett Horticulture story for further details. Groundwater boresThere are many registered groundwater bores across the catchment. Most groundwater extraction is from the Elliott Formation Aquifer and in the alluvial and sand systems. Farm dams are used as holding tanks to retain water for use around the farm in irrigation systems, and to pump water direct to crops. Surface and groundwater resources of the Kolan catchment are regulated by the Burnett Basin Water Resource Plan. The Burnett Water Plan ensures sustainable water use including supporting surface and groundwater dependent ecosystems. Under the water plan, surface water and groundwater is managed close to the coast, especially on the marine plain where saltwater intrusion has occurred in the groundwater previously. Departmental bores are regularly monitored for groundwater and salinity levels as part of the Coastal Burnett Groundwater Management Area. See the Wide Bay-Burnett Horticulture story for more information. Water qualityWater quality for people and environmentWaterways, wetlands, estuarine and marine systems are all environments that provide critical ecosystem services and have high tourism, aesthetic, cultural, recreational and economic values. The values can be impacted by poor water quality from urban, peri-urban, industry and agricultural land-uses. The Kolan is a Great Barrier Reef catchment. Runoff from the Kolan catchment enters to the southern Great Barrier Reef lagoon and Coral Sea to the north of Bundaberg, and the catchment forms part of the broader Great Barrier Reef ecosystem. Poor water quality, which can be caused by elevated levels of fine sediments, nutrients and pesticides, has a detrimental impact on Great Barrier Reef ecosystems, particularly freshwater, estuarine, coastal and inshore marine ecosystems. Increases in the volume and speed of runoff can increase erosion in the landscape and stream channels, resulting in sediment being carried downstream and reduced water quality. Water quality is also influenced by runoff and point source inputs such as sewage treatment plants (STPs) and additional inputs such as septic tank seepage and stormwater discharge. The nearest STP is at Gin Gin. It receives sewage from the local area, however most of the catchment uses septic tanks. These areas are also serviced with town water sourced from bores and the BWSS, however water for most of the catchment is supplied by private bores or rain tanks. Water quality policies and programsThe Australian and Queensland governments have a joint commitment to protect the Great Barrier Reef, formalised through strategic plans, such as the Reef 2050 Long-Term Sustainability Plan, the Reef 2050 Catchment Water Quality Strategy and the Reef 2050 Wetlands Strategy. The intent of the Reef 2050 Catchment Water Quality Strategy is to improve the water quality flowing from the catchments adjacent to the Great Barrier Reef, including the Kolan River and wider Burnett Mary region. The strategy uses best available independent scientific advice as provided by the Scientific Consensus Statement 2022, and establishes water quality targets that have been set for the 35 river catchments, including the Burnett-Mary region, flowing to the Great Barrier Reef. These targets define how much land-based pollution needs to be reduced to meet the ecological thresholds that protect the Reef’s ecosystem, and supports their recovery. The Great Barrier Reef Catchment Loads Modelling Program, part of the Paddock to Reef program, estimates average annual loads of key pollutants (sediment, nutrients and pesticides) for each of the 35 catchments draining to the Great Barrier Reef. It assesses progress towards the Reef Plan 2050 water quality targets. A technical report has been prepared for the Burnett Mary region. Key features> - SummaryKey features of the Kolan catchment include:
The subcatchmentsA 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. Larger catchments are made up of smaller areas, sometimes called subcatchments. The Kolan catchment consists of large and small subcatchments . Within a subcatchment, reaches of a river or creek and its surrounds are broken down into sub-units based on similar characteristics. The characteristics of each subcatchment are different, and therefore water will flow differently in each one. The Burrum catchment includes the following subcatchments and sub-units. Main channel of the Kolan:
Major tributaries:
Subunits of the Elliott escarpment, coastal dune systems and floodplain:
Kolan River main channelUpper Kolan (high elevation)Old, hard metamorphosed sediments and volcanics (arenite-mudrock, diorites), fractured and faulted geologies underlie the Upper Kolan (high elevation) subunit. Granites underlie the eastern, highest and wettest parts of this subunit. Most of the subunit is remnant vegetation, with parts of the valleys and riparian areas cleared for grazing. Kalpowar State Forest in the west includes native eucalypt forest and pockets of rainforest, together with hoop pine plantation. On the mountainous plateau in the northeast, Bulburin National Park preserves the largest stand of subtropical rainforest in central Queensland, together with New England blackbutts (Eucalyptus andrewsii) towards their northern range limits, a population of endemic macadamia trees (Macadamia jansenii), dry rainforest and emergent hoop pine. Upper Kolan River, Photo by Queensland Government The narrow river channel flows intermittently through steep-sided banks from waterhole to waterhole. Parts of the subunit support subcoastal non-floodplain tree swamps (eucalyptus, casuarina and melaleuca). High seasonal rainfall in this subunit contributes to the reliable water storage of Lake Monduran. Upper Kolan above Fred Haigh DamThe Upper Kolan above Fred Haigh Dam subunit includes Lake Monduran, which is impounded by the Fred Haigh Dam with a capacity of 562,000 megalitres. Geology consists mainly of granitoid and metamorphic rock. There is a basalt flow and other volcanic geologies near the dam wall, with the wall built on a natural constriction in the landscape. Narrow alluvial flats (porous aquitards) line parts of the valleys. The main channel of the Kolan River enters Lake Monduran from the north. Takilberan Creek runs to the south through a plateau adjoining Bania National Park and Wonbah State Forest, before heading northwards to Lake Monduran. In the east, Tararan Creek skirts a basalt plateau before heading north to Lake Monduran. Both Tararan Creek and Walily Creek to the north are largely cleared and grazed with limited riparian vegetation. Northeast of the dam is Monduran State Forest. The subunit has been largely cleared. The national parks support dry vinescrubs, eucalypt forest and woodlands. Hillslopes and valleys are grazed. Average rainfall is 1,200 millimetres per annum. Terrain is hilly and runoff can be fast from the tributaries that flow into Lake Monduran. The water supply from the catchments leading into Lake Monduran support horticulture and cane production in the Kolan, Burnett and Burrum catchments. Water is transferred from Lake Monduran to the Burnett catchment via a channel and pipes that run across from Lake Monduran and Gin Gin Creek. The water then flows into the irrigation system and network of storages and pipelines in the Burrum catchment (Isis, Gregory and Elliott subcatchments). Water is also released downstream to the Bucca weir and Kolan barrage. Lake Monduran is stocked with barramundi (Lates calcarifer), Australian bass (Percalates novemaculeata), saratoga (Scleropages leichardti), silver perch (Bidyanus bidyanus) and sooty grunter (Hephaestus fuliginosus). Irrigation canal at Damascus, Photo by Gary Cranitch © Queensland Museum Fred Haigh Dam to Gin Gin Creek junctionIn the Fred Haigh dam to Gin Gin Creek junction subunit, the Kolan River passes through mixed metamorphosed sedimentary and volcanic rocks (Gympie Group), with granites to the northeast. In the east of the subcatchment lies the volcanic Graham’s Creek Formation, the oldest rocks of the Maryborough Basin. In the upper parts, Littabella National Park adjoins Monduran State Forest. Stony Creek passes through a lower section of Monduran State Forest (plantation) and joins Four Mile Creek before entering the Kolan River. Grazing occurs along the hillslopes and valleys and citrus is grown along the alluvial terraces on either side of the Kolan River. Gin Gin Creek junction to Bucca Weir nIn the Gin Gin Creek junction to Bucca Weir subunit, the Kolan River passes through a gorge of hard Maryborough Formation rock adjacent to alluvial terraces (older) and then alluvial flats (younger) along the river. To the south are sedimentary rocks (Brooweena Formation). Where alluvium remains vegetated, they contain wetlands (eucalyptus on alluvial). Alluvial deposits are aquifers. The river channel bends north around cliffed, hard rocks, flowing rapidly through the gorge downstream to the weir. Turtles inhabit the weir pool, notably Krefft’s river turtle (Emydura macquarii krefftii). Bucca weir pool extends approximately 13 kilometres upstream, to the Gin Gin Creek confluence, over alluvial flats. The sodic soils of the alluvial terraces are vulnerable to erosion. Bores extract groundwater from the alluvial aquifer, which together with water from the weir supports tree crops growing on the alluvial terraces and flats, including macadamias and avocados. Kolan River at Bucca, Photo by Gary Cranitch © Queensland Museum Bucca Weir to Avondale BarrageA fault line has exposed older geologies of the Maryborough Basin in the Bucca Weir to Avondale Barrage subunit. West of the Maryborough Formation are volcanics of the Graham’s Creek Formation. The river bends southward through a gorge of Maryborough Formation onto wider alluvial terraces and flats to the south of the river, flanked by sedimentary rocks of the Burrum Coal Measures to the north. South of the main channel is mostly Elliott Formation, which supports a groundwater system. The gorge and downstream river channel support a series of riffles containing ribbon weed (Vallisneria sp.). These systems provide habitat for a range of fauna such as sensitive macroinvertebrates, turtles, including Krefft’s river turtle (Emydura krefftii), broad shelled river turtle (Chelodina expansa) and eastern snake-necked turtle (Chelodina longicollis); and platypus (Ornithorhynchus anatinus). Water is released from Bucca Weir to support the riffle systems. Kolan River at AvondaleThe fast-flowing water also supports recreational canoeing and there is a popular picnic spot at Bucca Crossing. Bucca Creek enters from the north, while further downstream the river meanders northward through a vegetated channel adjacent to alluvial flats. The Kolan Barrage at Avondale separates fresh and salt water. The upper reaches and hills surrounding Bucca Creek are mostly cleared, but middle reaches retain riparian vegetation. Several small and large farm dams occur in this subcatchment and support grazing, mostly on the Burrum Coal Measures, together with some horticulture north of the main channel. Bores extract groundwater from the alluvial aquifer. Macadamias and avocados are grown on the alluvial terraces, mainly on the southern bank of the Kolan River. Sugar cane grows on the alluvial flats and there are avocado orchards near Avondale. Kolan estuarine reachSedimentary Burrum Coal Measures extend either side of the Kolan estuarine reach subunit forming a natural constriction. Downstream of the constriction the river meanders across alluvial flats up to four kilometres wide. Either side of these alluvial flats are elevated plateaux of porous Elliott Formation sediments that provide for groundwater recharge and storage. Surrounding the river mouth is a Holocene dune system that forms a sand spit and island to the south, connected to a swale system. All these systems contain aquifers. To the south the Elliott escarpment is very productive and intensively farmed. The Elliott Formation Aquifer to the north of the Kolan River is too shallow for irrigation supply and remnant vegetation remains. Sugar cane is grown on large areas of the alluvial flats and there is very little riparian vegetation, and significant erosion. Mangroves grow along the river towards the mouth. The river becomes a series of channels and islands to the south within the Kolan River Conservation Park and is a declared fish habitat area. . Wetland at Moore Park Beach Major tributariesGin Gin CreekSouth of the upper Kolan subcatchments, Gin Gin Creek flows eastward through a rugged hilly landscape. The upper parts are granite together with old, hard metamorphosed sediments and volcanics (andesites and rhyolites). Coarse grained, shallow, sodic soils are derived from the granites (quartz, clay, felspar). Basalts (Tirroan to Gin Gin) and pockets of Elliott Formation duricrusts and deeAverage annual rainfall is lower than the upper subcatchments of the Kolan River (1,000 millimetres per year). Runoff is rapid from the hard upper parts. The creek channel is incised, lacking permanent flow except where Bucca weir backs up into the channel. Riparian wetlands along the alluvial flats contain blue gum, allocasuarinas and casuarinas. Land use is mainly grazing and sugar cane in the upper parts to Tirroan and Gin Gin. A channel and pipeline from Lake Monduran cross Gin Gin Creek, transferring water to the Burnett catchment for cane and tree crop horticulture (macadamias, citrus, avocados, mangoes). Basalt and Elliott Formation sediments are aquifers. There are many small farm dams and local bores that extract water from alluvial aquifers. Yandaran CreekFreshwater to marine connectivity is a key feature of Yandaran Creek . It has significant values as a fish nursery especially for diadromous fish and includes a declared fish habitat area. Terrain is hilly in the north and flat in the south. Geologies are diverse and include the Maryborough Basin and the Graham's Creek Formation volcanics in the upper catchment, intersected to the east by a north-south ridge of hard Maryborough Formation (arenite-mudrock). Downstream are sedimentary rocks of the Burrum Coal Measures and Elliott Formation shallow duricrusts. Alluvial flats occur mainly on the southern bank of Yandaran Creek. The creek runs intermittently into waterholes, notably in the Maryborough Formation, and then into a series of rocky bars and pools and ultimately the tidal declared fish habitat area. Land use is mostly grazing, with some sugar cane and macadamia horticulture. Large flood flows previously deposited alluvial soils on the estuarine flats at the confluence with the Kolan River. Some high flood flows can successively erode the banks. Elliott escarpment, marine plain and floodplainThe Elliott escarpment is a slightly elevated plateau spanning the Kolan and Burnett catchments. It provides a productive groundwater system with porous, well-drained Elliott Formation sediments, which together with the Bundaberg Water Supply Scheme (BWSS) provide the ideal conditions for irrigated intensive horticulture (mixed crops and tree crops). Groundwaters from the escarpment feed into the Kolan and Burnett catchment, via deep drainage and direct runoff, and also onto the coastal sand system. Between the Kolan and Burnett river mouths, older Pleistocene sand backs onto a younger Holocene dune system, which acts as a floodplain that joins the two basins during large flood events. The low-lying dune system has been levelled for agriculture, which is irrigated by a mix of reticulated water from the Bundaberg Water Supply Scheme (BWSS) and groundwater. A system of drainage canals has also been excavated into the dune system in the south to drain the high watertable and reduce waterlogged soil and enable sugar cane to be grown. As most of the area is below the level of highest astronomical tide, and the floodgates are leaky, there is some tidal flow and continued mangrove growth. In the north, a slightly more elevated Holocene sand-barrier dune-swale system joins the Kolan mouth and the Burnett delta, which is a series of channels parallel with the dunes, interspersed by entrances to the sea. The northern part of the Elliott escarpment is the most productive part for horticulture, and includes mixed annual small crops (e.g. sweetpotatoes, strawberries), with extensive tree crops (macadamias) to the west and south. Macadamia irrigation practices aim to contain surface water within the landscape. Rural residential properties with small dams lie along the northern edge of the plateau. Larger dams on drainage lines capture water running off the landscape. A network of pipelines distributes irrigation water from the Gooburrum balancing storage in the southwest (part of the Bundaberg Water Supply Scheme). Stony Creek off the Elliott escarpmentThe Stony Creek subunit drains the western side of the Elliott escarpment. It joins the Kolan River downstream of Bucca weir, where the alluvial floodplain narrows between the Elliott Formation (south) and the Burrum Coal Measures (north). The creek is largely groundwater-fed by the Elliott Formation Aquifer, recharged by direct rainfall percolating into the porous soil. Several large farm dams provide irrigation for crops and there are many small dams on rural residential properties. Tree crops (macadamias) are grown in the east. Elliott escarpmentThe Elliott escarpment subunit is a small area underlain by Elliott Formation. Large areas are cleared for sugar cane, horticulture and residential, however some areas retain eucalypt forest. Cane train, Welcome Creek, Photo by Queensland Government Kolan/Burnett dune systemThe Kolan/Burnett dune system subunit (and alluvial floodplain) wrap around the Elliott escarpment, supporting mangrove wetlands in the north and east. The older Pleistocene dunes of the marine plain have a lower relief, with coarser sediments than those of the higher relief Holocene dune-swale system in the east. Clays are deposited across the marine plain when submerged during major floods. Major flood flows can also reconfigure the entrances of the Kolan River and Burnett River. Moore Park Beach, Photo by Queensland Government A network of freshwater swale wetlands connects to mangroves, saltmarsh, tidal flats and channels, apart from where roads and causeways cross the marine plain. Marine to freshwater hydrological connectivity allows diadromous fish (e.g. mullet, mangrove jack) to access habitat required to complete critical life stages. Protected migratory shorebirds such as the bar-tailed godwit and far eastern curlew roost in the mangroves and marine turtles nest along the beach. The declared fish habitat area and mouth of Kolan Conservation Park recognise these values. Sugar cane is farmed on the artificially drained sandy swales. A network of channels and floodgates has been installed to prevent saltwater ingress, however some saltwater seeps in and there are some mangroves. Elliott Escarpment to Moore Park Beach and Quaternary DunesDownstream escarpment to Moore Park beach and Quaternary dunes subunit, Croome Creek drains off the Elliott escarpment along the middle of the plateau. It crosses the levelled Pleistocene dunes of the marine plain to emerge beyond the Holocene dunes. Croome Creek intersects an artificial drainage network of canals and floodgates between the canefields and flows through Holocene dunes to the sea north near Moore Park. The Holocene dune system provides connections from fresh to salt water, which provides critical fish breeding habitat and nurseries. A patch of protected microphyll / notophyll vine forest is surrounded by wetlands. The protected Coxen’s fig parrot (Cyclopsitta diophthalma coxeni) has been sighted in this area. Sandbanks of the estuary provide high tide roosting site for migratory shorebirds including bar-tailed godwit, far eastern curlew and lesser sand plover. Moore Park Beach is significant for turtle nesting, however, the shoreline has been eroding ( Digital Earth Australia Coastlines data ). Sugar cane is farmed on the levelled Pleistocene dunes. East of the Kolan estuary, the township of Moore Park Beach extends along a 6 kilometre strip of the Holocene dune-swale system between the two estuaries. Roads disrupt hydrological connections between fresh and marine ecosystems. The pH of drains can be low and acid sulfate soils have been recorded. The Moore Park Beach water supply is a mix of Bundaberg Water Supply Scheme reticulated water and groundwater, and sewage is managed by septic systems. Elliott escarpment to Quaternary dunes (Welcome and Sandy creeks, Elliott escarpment to Skyringville) drain the southeastern corner of the Elliott escarpment. These creeks form incised channels that flow towards the marine plain until they are diverted into an artificial drain running eastward towards the Burnett catchment. Welcome Creek also runs northward into the rectangular network of drains behind Barubbra Island. Land use on the plateau consists of irrigated horticulture (small crops such as strawberries, sweet potatoes) and tree crops (macadamias). Sugar cane is farmed on the levelled Pleistocene dunes which are widest here where they meet the floodplain of the Burnett River. ConclusionThe Kolan catchment shows how natural and modified features within the landscape affect how how water flows. These issues need to continue to be managed to ensure that the significant natural, cultural and social values of the catchment are protected and maintained, and to minimise impacts within the catchment to the receiving waters of Great Sandy Marine Park and downstream in the Great Barrier Reef, while providing for residential, farming and other important land uses of the catchment. Knowing how the catchment functions is also important for future planning, including climate resilience. With this knowledge, we can make better decisions about how we manage this vital area. AcknowledgmentsDeveloped by the Queensland Wetlands Program in the Department of the Environment, Tourism, Science and Innovation in collaboration with local partners.
This resource should be cited as: Walking the Landscape – Kolan Catchment Story v1.0 (2026), presentation, Department of the Environment, Tourism, Science and Innovation, Queensland. Images provided by: Burnett Mary Regional Group and Gary Cranitch © Queensland Museum The Queensland Wetlands Program supports projects and activities that result in long-term benefits to the sustainable management, wise use and protection of wetlands in Queensland. The tools developed by the Program help wetlands landholders, managers and decision makers in government and industry. Contact wetlands@detsi.qld.gov.au or visit https://wetlandinfo.detsi.qld.gov.au DisclaimerThis catchment story has been prepared with all due diligence and care, based on the best available information at the time of publication. The department holds no responsibility for any errors or omissions within the document. Any decisions made by other parties based on this document are solely the responsibility of those parties. Information contained in this education module is from a number of sources and, as such, does not necessarily represent government or departmental policy. Data source, links and informationSoftware UsedArcGIS for Desktop | ArcGIS Online | ESRI StoryMaps Some of the information used to put together this catchment story can be viewed on the Queensland Globe. The Queensland Globe is an interactive online tool that can be opened inside the Google Earth™ application. Queensland Globe allows you to view and explore Queensland spatial data and imagery. You can also download a cadastral SmartMap or purchase and download a current titles search. More information about the layers: Source Data Table Flooding Information: Bundaberg Regional Council Fraser Coast Regional Council North Burnett Regional Council Other references*Note - If you have been directed here via a reference hyperlink, to return to the section you were previously reading, use your browser's 'back button' to resume reading where you left off.*
Last updated: 28 July 2026 This page should be cited as: Department of the Environment, Tourism, Science and Innovation, Queensland (2026) Kolan catchment story, WetlandInfo website, accessed 4 August 2026. https://wetlandinfo.detsi.qld.gov.au/wetlands/ecology/processes-systems/water/catchment-stories/kolan/ |
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