Shire of Chapman Valley
|Area||~3,965 square kilometres, located ~440 km north of Perth.|
|Towns||Nabawa, Nanson, and Yuna|
|Average Temperature||Mean daily maximum temperature over 30 years 1990 – 2019 Coastal: 32.7°C (Jan) and 20.5°C (Jul); Inland: 37.5°C (Jan) and 19.7°C (Jul).|
|Annual Rainfall||Average annual rainfall over 30 years 1990 – 2019 Coastal: 394 mm; Inland: 315 mm (BoM 2020).|
|ABS Profile||Chapman Valley ABS profile|
|Shire Website||Shire of Chapman Valley|
Over 1,400 people live in the Shire of Chapman Valley, with the majority of those people living in the peri-urban areas in the southwest of the Shire, near the City of Geraldton (ABS 2016).
The population in the Shire of Chapman Valley increased by 22% between the last census in 2011 and the most recent census in 2016, and is projected to continue to increase by a further 5% by 2031 (DPLH 2016).
Approximately 13% of residents of the Shire of Chapman Valley were born overseas and approximately 4% are of Aboriginal and / or Torres Strait Islander descent.
Estimates of the resident populations as at 30 June are released annually for Local Government Areas (LGAs) in Australia by the Australian Bureau of Statistics. The estimates are generally revised 12 months later and final estimates are available after the following census. Visit the ABS website for further details.
The main land uses in the Shire of Chapman Valley are agriculture, rural residential and nature conservation.
Wokatherra Nature Reserve
The Wokatherra Nature Reserve covers ~146 ha and is located in the Chapman Valley. The reserve forms part of the Yamatji conservation estate.
Weirmonger Nature Reserve
The Weirmonger Nature Reserve covers ~10 ha and is located near East Yuna. This small patch of remnant vegetation is completely surrounded by agricultural land. The reserve forms part of the Yamatji conservation estate.
Wandana Nature Reserve
The Wandana Nature Reserve covers ~69 000 ha and is the only Nature Reserve within the Geraldton Hills subregion of the Geraldton Sandplains bioregion. The reserve is an incredibly diverse and important refuge for flora and fauna in the region.
Protheroe Nature Reserve
The Protheroe Nature Reserve covers ~88 ha and is located west of Nabawa. The reserve forms part of the Yamatji conservation estate.
Oakajee Nature Reserve
The Oakajee Nature Reserve covers ~161 ha and is located south of Howatharra. The reserve forms part of the Yamatji conservation estate.
Oakabella Nature Reserve
The Oakabella Nature Reserve covers ~43 ha and located north of Bowes. The reserve forms part of the Yamatji conservation estate.
Nilligarri Nature Reserve
The Nilligarri Nature Reserve covers ~9ha and is located near the Bowes homestead. The reserve forms part of the Yamatji conservation estate.
McGauran Nature Reserve
The McGauran Nature Reserve covers ~1 098 ha and is located just outside of East Yuna. The reserve forms part of the Yamatji conservation estate.
Mallee Nature Reserve
The Mallee Nature Reserve covers ~333 ha and is located north east of Binnu.
Howatharra Nature Reserve
The Howatharra Nature Reserve covers ~93 ha and is located east of Howatharra. The reserves forms part of the Yamatji conservation estate.
East Yuna Nature Reserve
The East Yuna Nature Reserve covers ~2 300 ha and contains high quality remnant vegetation which provides crucial habitat for rare flora and fauna.
Bindoo Hill Nature Reserve
The Bindoo Hill Nature Reserve covers ~840 ha and was initially established as a water reserve. The reserve consists mostly of undulating hills and stony outcrops of Tumblagooda sandstone and it is a good place for viewing Geraldton Sandplains shrubland, heath and woodland vegetation.
Bella Vista Nature Reserve
The Bella Vista Nature Reserve covers ~90 hectares and is located near Nanson.
The coastline of the shire is dominated by the Cattamarra Coal Measures, formed during the Jurassic period from volcanic and sedimentary rocks and consisting of siltstone, shale, claystone, coal and sandstone. Just inland, the underlying geology is the Northampton complex, which consists of migmatitic and paragneiss rocks. Further east, the shire lies on a complex of formations, including the above and Tumblagooda Sandstone, the Yarragadee Formation and Holmwood Shale. Tumblagooda Sandstone consists of fine to coarse grained red-bed sandstone and minor siltstone. The Yarragadee formation was formed during the Jurassic period from volcanic and sedimentary rock and consists of sandstone interbedded with shale. Holmwood Shale was formed during the Permian period from sedimentary and volcanic rock and consists of grey shale and clayey siltstone interbedded with limestone. The north east portion of the shire lies primarily on the Nangetty formation, formed during the Carboniferous-permian period from sedimentary and volcanic rocks and consisting of diamictite, shale and sandstone.
Coastal soils are deep and sandy. Soils to the east consist of sodic subsoils, red loamy duplexes, sandy duplexes and siliceous coloured sands. The red loamy duplexes are often associated with drainage lines in the area. Red shallow loams, red to brown hardpan soils and deep sandy earth are associated with the undulating plains and breakaways of the shire.
The shire is located within the Geraldton Hills (GES01) and Edel (YAL01) IBRA sub-regions and is characterised by sandy proteaceous heath, casuarina scrub, and low close acacia shrublands. The Edel subregion is unique because it is a transition zone for flora and fauna between the South West and Carnarvon Bioregions. Patches of Subtropical and Temperate Coastal Saltmarsh can be found in the shire. This is a nationally protected Threatened Ecological Community listed as vulnerable under Australia’s national environment law. The plant, animal and micro-organism community is found in the intertidal zone, often associated with estuaries. The plant community consists mainly of salt-tolerant vegetation (halophytes) including grasses, herbs, reeds, sedges and shrubs. Several Priority Ecological Communities occur in the shire, including Acacia rostellifera and mallee eucalypt Coastal Sands, the plant assemblages of the Moresby Range System and the Frankenia pauciflora shurblands on Tamala Limestone ridges.
The coastline of the Northern Agricultural Region consists mainly of sandy beaches backed by low dunes, valued for recreational, aesthetic and cultural reasons and as storm protection and habitat. Primary dunes, or foreshore dunes, refer to the first system of dunes shoreward of the low water mark. These dunes typically support little vegetation. Secondary dunes, or back dunes, are undulating, sandy ecosystems located further from the water.
The Central West Coast limestone reef system extends from Kalbarri to Perth and supports an extremely high species diversity of seagrasses. Extensive seagrass meadows in protected, near-shore areas of the NAR, provide shelter and nursery habitat for many fish and other marine creatures including Western Rock Lobster. Seagrasses also provides services as primary biomass producers, sources of dissolved oxygen, sediment traps and nutrient cyclers.
Gascoyne Groundwater Area
The Gascoyne Groundwater Area extends north to Kalbarri and bounds the Arrowsmith Groundwater Area east to pastoral country. The largest groundwater aquifer occurs in the Yarragadee Formation, which has an estimated yield of 22.5 million m³/year. Groundwater from fractured rock aquifers in the eastern, inland part of the region is predominantly saline, with poor yields.
Drainage Basin Length (km) Catchment Area (km2) Average Stream Salinity (mg/L) Key Characteristics Greenough 80 1,644 3000-35000 Originates east of Yuna and drains the farming areas of the Chapman Valley. The river enters the ocean within the northern suburbs of Geraldton and is only open to the ocean during winter ﬂows.
River Length (km) Catchment Key Characteristics Buller 10 33.9 The Buller River head waters rises 25 km north of Geraldton and meanders in a southerly directions before discharging into the Indian Ocean approximately 4 km north of Drummonds Cover.