 More tributaries including Ellen Brook, Jane Brook, Henley Brook, Wandoo Creek, Bennett Brook, Blackadder Creek, Limestone Creek, Susannah Brook, and the Helena River enter the river between Wooroloo Brook and Guildford; however, most of these have either dried up or become seasonally flowing due to human impacts such as land clearing and development.Between Perth and Guildford the river goes through several loops.Originally, areas including the Maylands Peninsula, Ascot and Burswood, through Claise Brook and north of the city to Herdsman Lake were swampy wetlands.