瓦爾河
Rain and underground water collects in pans, vleis and streams and where these connect, the westward flowing Vaal River is born. The river flows west into the Grootdraai Dam near Standerton, Mpumalanga. On its course to the Vaal Dam in Vereeniging, the river is joined by a number of tributaries. The Little Vaal River starts in an escarpment near Ermelo. Near Memel in the Free State is where the Klip River begins. The Watervals River begins in Secunda, Mpumalanga. The Wilge River used to meet the Vaal River before the Vaal Dam was built in 1938; now the water flows straight into the dam.