Several thousand people gathered in Christchurch to protest at the way Canterbury's water will be managed in future.

The protest attracted people from groups such as Forestry and Bird, Fish and Game to the Anglican Church amid fears that big business and dairy interests will dictate what happens.

Stones from the South Island's great rivers were used to build a cairn in front of ChristChurch Cathedral as part of the protest on Sunday.

"It's about the people of Canterbury coming together and saying you can't just suspend our environmental laws and democracy and think you can get away with that," said Our Water Our Vote spokesman Chris Todd.

The Dean of Christchurch, the Very Rev Peter Beck, also voiced concerns about management and quality of Canterbury's water.

Earlier this year, there was outrage when Canterbury's regional councillors were sacked and replaced by government-appointed commissioners, leaving ratepayers without a say.

There has already been concern about the amount of water used by the dairy industry and many protesters are worried the commissioners will give the green light to more development, putting even greater pressure on the rivers and underground aquifers.

The future of the Hurunui and Rakaia Rivers is also in the spotlight. Water from both catchments is wanted for more irrigation but opponents believe the rivers are under threat. 

They say the conservation orders - which would protect the rivers - have been weakened by legislative changes.

The protest went peacefully but organisers warn the war over water has only just begun.