Major Towns: Coolum Beach
Subcatchment Area: 830 Ha
Rainfall: 1730 mm/yr (Coolum Beach Post Office)
Major Land Uses:
- Native Vegetation – 430 Ha
- Urban – 335 Ha
The summit and upper slopes of Mt Coolum, the upper catchment of the south arm, support small fragments of banksia heath lands, populated by dwarf White Banksia (Banksia integrifolia), with a shrub layer of Dogwood (Jacksonia scoparia) and Leptospermum species. This gives way to remnant fragments of Forest Red Gum (Eucalyptus tereticornis) open forest on the lower slopes and foothills. This grades to open forests of Scribbly Gum (Eucalyptus racemosa), which occur on the crests and upper slopes of the low sandstone hills. The lower slopes are populated by Broad-leaved Tea-tree (Melaleuca quinquenervia) woodland, which grades to closed forest on the wetter, low lying areas around drainage lines and in coastal swamps.
The north arm flows through Wallum Heath, which consists of areas of open heath populated by Wallum Tea Tree (Melaleuca nodosa) Swamp Banksia (Banksia robur) and Grasstree species (Xanthorrhoea sp.) in the low lying, wetter areas, intergrading with sedgeland.
|Although vegetation covers more than half of the Stumer Creek catchment (52%), urban areas (41%) are rapidly gaining as many new housing estates are under construction or planned. All other land uses account for the remaining 7% of the land area. The vegetated areas of the catchment are concentrated in the northern half, with the southern half being almost entirely urban.
Although not part of the Maroochy River Catchment, Stumer Creek is closely associated to it as it drains a coastal area between the Maroochy Catchment and the ocean.
Stumer Creek is a two-branched coastal creek draining the area around the town of Coolum and the wetlands in the southern end of the Noosa National Park. The north and south arms diverge very close to the mouth. The upper catchment of the south branch begins on Mt Coolum, a Tertiary Trachyte plug that dominates the surrounding area. To the north of Mt Coolum are low sandstone hills that also drain into the south arm of the creek. The lower reaches of the south arm, and the entire north arm drain areas Holocene windblown sand plains.
The mouth of Stumer Creek is often plugged by ocean sand during periods of low rainfall, forming a lagoon. This situation is only altered when sufficient rain falls in the catchment to develop a flow strong enough to erode the sand plug. The mouth of Stumer Creek is constrained in a relatively stable position by outcrops of organic sand rock under the beach.
The steepness of the upper catchment of the south arm means that the stream is ephemeral, only flowing during periods of prolonged heavy rain. The creek rises very quickly due to the impervious nature of the urbanized upper catchment. The creek channel is deeply incised in the upper reaches, but is heavily modified in the middle and lower reaches by flood mitigation works.
The north arm rises in the foothills of Mt Peregian, and associated low hills. The stream originates in the Wallum wetlands of the Noosa national park, with the channel not coalescing until two-thirds down its length, close to the confluence with the south arm. In contrast, the north arm has not been modified by flood mitigation works.