The Avoca River drains a substantial part of central Victoria. The river rises at the foot of Mount Lonarch near the small town of Amphitheatre, and flows north for joined by thirteen minor tributaries and through the towns of, and. Two major distributaries leave the Avoca River between Charlton and Quambatook, Tyrrell Creek, flowing to Lake Tyrrell and Lalbert Creek flowing to Lake Lalbert. Although the Avoca River basin is part of the Murray-Darling basin, the Avoca River does not empty into the Murray. Nowhere a large stream, it dwindles as it flows north, eventually terminating in the Kerang Lakes, a network of ephemeral swamps west of Kerang and about south of the Murray River. Although the Avoca River has a substantialcatchment area, the fifth largest in Victoria, most of that area is on the northern plains where rainfall averages only about per year, and where there is little runoff as the terrain is very flat. The mean annual runoff of per annum accounts for only 0.67% of Victoria's runoff. Most of the water flowing in the Avoca River originates in the narrow upper portion of the catchment area, where rainfall averages about per year, most of it falling in the winter and spring. Of all the Victorian rivers in the Murray-Darling basin, the Avoca River is the most variable. The average annual flow is, however recorded actual flows have varied from almost five times the average figure in very wet years to 0.5% of the average in drought years. It has an extremely variable flow, ranging from long periods of low flow that are less than per day to floods. In dry years, flow stops for many months. Although it is the only river of significance in the area, the Avoca River has had no major water storages constructed on it, merely six weirs of only local significance. Little use of the river is made for irrigation as during the peak demand periods of summer and autumn, the river is often not flowing. During low flow periods the Avoca River water is usually too saline to water crops with, but can still provide drinking water for sheep and cattle. The river is crossed by the Pyrenees Highway at Avoca; and the Borung Highway and the Calder Highway at Charlton.
Etymology
As the river is relatively long, indigenous peoples from various cultural groups lived near the river course. In the indigenousDjadjawurrung, Wathawurrung, Wergaia, and Wembawemba languages, the river has several names including Natte yaluk and Boca both with no clearly defined meaning; Bangyeno Banip meaning bunyip waterholes; Djub-djub-galg meaning a place where melaleuca was abundant; Witchelliba with witji meaning basket grass and bar meaning river; and Yangeba with no clearly defined meaning.
