Williamstown Child Care Centre Co-operative, which opened in 1986 with 22 children, has objected to a proposal for a 79-place centre behind StAndrew's Presbyterian Church.

The co-op has joined Cecil Street residents, the latter having major traffic concerns, in lodging an appeal with the Victorian Civil and Administrative Tribunal.

The controversial centre was approved by two votes to one at a Hobsons Bay Council planning committee meeting on June 17.

Williamstown North ward councillor Peter Hemphill voted against the proposal, stating there could have been a better proposal with access off Hanmer Street.

Seabrook ward councillor John Hogg and Altona North ward's Michael Raffoul voted in favour of the new centre, which will be leased by the church to Kids by the Bay.

As reported by the Advertiser last month, Reverend Bruce Riding said there was enough demand to justify three more child-care centres in the area.

However, co-op chairman Thane Joske said her tiny centre might now have to move.

"Obviously, we recognise there is significant demand for child care and kinder places in the Williamstown region, but it would be a great shame for this to be achieved at the expense of our well-established, community-owned and operated centre," she said.

"We believe both centres can co-exist and meet the requirements of the local community. We're at risk of actually having to relocate, ultimately, because we can't expand on our current site."

Ms Joske said new child-care regulations, including smaller child-staff ratios and bigger outdoor space requirements, meant the co-op either had to expand or lose four children.

She said the co-op had presented two expansion proposals to St Andrew's, but both had been rejected.

"We're a community centre with just 42 places that caters to all socio-economic groups within Williamstown," she said.

"With changes to legislation, our fees will have to increase and may present a significant financial impact to many families. As a consequence, it's likely to decrease the cultural diversity now enjoyed by the centre."

Co-op co-ordinator Sue Evans confirmed there were 140 families on its waiting list, not 300 as claimed by Reverend Riding.