Organisers of an anti-gas blockade on the New South Wales north coast hope a large turnout of protesters shows politicians that there is strong community opposition to the industry. About 1,000 protesters have turned up at Bentley to show their support for a delegation of local landholders travelling to Sydney.

Eight local landholders, including Ross Joseph, are travelling to the city to voice their concerns about gas extraction in the Northern Rivers.

They say people at the Bentley blockade are not extremists; but farmers and community members who want to protect where they live.

Mr Joseph says they are concerned about what operations on the neighbouring property will do to their aquifers.

Metgasco's managing director, Peter Henderson says the community should have no concern about the impact of gas drilling and production practices - conventional or unconventional - on aquifers or local water supplies.

"Drilling practices, which include the use of multiple layers of steel and cement to isolate aquifers from the well, ensure that aquifers and water supplies are not affected," Mr Henderson says.

"Metgasco respects the rights of people to protest and express different views. However, we expect people to respect our lawful rights and those of the farmer we are working with."