The catchment has a total area of 13,800 square kilometres (5,328 sq mi) and is 80% cleared for agriculture.

The river mouth at Guilderton typically closes during the summer months due to insufficient water flow, creating a sandbar.

[7] The river is prone to periodic flooding unusually following cyclones and tropical depressions crossing the coast further north.

[8] More floods occurred in 1917 when 1.7 inches (43 mm) of rain fell in three hours at Mogumber with similar falls in surrounding areas.

Railway lines were undermined to a depth of 30 feet (9 m) leaving Moora isolated from Perth by both road and rail.