Waimakariri River

Waimakariri River

This view illustrates the source of the gravels that make up the Canterbury Plains. A shingle fan coming down from the mountains carries shattered greywacke rocks to the river bed. The river in turn transports these rocks down to the sea, changing them into rounded boulders. Around Christchurch there are many pits where these gravels are dug up, washed, and crushed for use in construction projects.