The Werribee River begins near Leonards Hill, on the southern slopes of the Great Dividing Range just to the north and east of Korweinguboora when a number of small creeks join, in the Wombat State Forest.
The creeks commence from slopes around Leonards Hill (739m above sea level), Beavers Hill (716m) and Edwards Hill (708m), between Kurweinguboora and Bullarto South. These creeks near Kurweinguboora begin on undulating farm land, or inside Wombat State Forest.
Creeks forming on Slopes north of the Leonards Hill to Ballarto South Road, flow north to the Loddon River, while those to the west of Kurweinguboora flow to the Moorabool River catchment. Creeks flowing between Blakeville and Green Hills flow into Pykes Creek reservoir and southward to the Werribee River.
The climate of the area is classified as cool-temperate to Mediterranean zone with cold and wet winters (May-Aug) and warm and dry summers (Dec-Feb). Mean annual rainfall in the region in the last 20 years was between 600-700 mm. http://www.forestscience.unimelb.edu.au/wombatflux
Some damp forest occurs in higher rainfall areas of the Wombat Forest where annual rainfall is between 950-1200mm per annum.
The forest has been logged over many years but is still home to some great scenery, walks and wildlife.
Wombat Forestcare Inc. says:
“The Wombat Forest contains a diverse range of native plants and animals, including a number that are listed as rare or threatened, such as Powerful Owl and the Wombat Bush Pea. As well as these natural values, the Wombat is a significant water catchment area, giving rise to six rivers.”
The river then flows southward, leaving the forest behind, passing through farmland on its way towards Ballan.
At Ballan if flows through the centre of this attractive town, providing the population with a flood plain which has been used as a golf course and recreational reserves. Parts of the river here are overgrown with Hawthorne (Crataegus monogyna) and other species. One such area is Caledonian Park, where quite large scale clearance of the exotic species has been undertaken and replaced by indigenous species.
Below Ballan these weed species have overgrown the watercourse and the river is not clear of them for some distance.