The next step towards Bristol's £70 million eco zoo has been taken after formal planning was submitted.

The 55-hectare park proposed for land at Cribbs Causeway, near junction 17 of the M5 motorway, Bristol, will be the first conservation-led animal visitor attraction of its kind in the UK.

If granted, work could start in 2010 on a zoo which will feature ecosystems such as Congo and Sumatra rainforest, Georgia wetlands, Tanzania savannah and Nepal grasslands.

Costa Rica swamp and Indian Ocean coral reef will also be created so animals will live in a setting to match their natural habitat.

A special feature will be the entrance to a Sumatran tiger enclosure, which will have a covered walkway partly sunk into the ground so visitors will emerge at eye level with the animals as the creatures drink from a watering-hole.

Structural engineer Birgit Schaffarra, from structural and civil engineering consultancy practice Buro Happold, said: "The zoo wants visitors to walk around and feel as if they are part of the various landscapes.

"They want to move away from that fenced-in feeling you often experience in zoos and the emphasis is on great respect for the animals."

She said the park was intended to be a conservation-led wildlife park that inspired people to think about protection of the natural world.

Bristol-based practice White Design has designed large parts of the scheme.

Architect Till Scherer said: "This world class project will combine both animal conservation and sustainability throughout, allowing visitors to think differently about the world they live in. Every aspect of the park's design incorporates sustainability, from the individual buildings and the engineering infrastructure to the landscape."

Natural materials such as timber and bamboo will be used in the construction, with eco-friendly power generation and waste management part of the plan.

It is estimated up to 400,000 visitors a year will be attracted to the park.

Bristol Zoo director Dr Jo Gipps said: "We are thrilled to have submitted to South Gloucestershire Council the planning application.

"Costing approximately £65-70 million, the park will contain an exciting mix of exhibits based on real eco-systems around the world.

"It will be the first conservation-led animal visitor attraction of its kind in the UK and will set a new benchmark for how zoos can support conservation in the wild and establish a more influential position in the global conservation movement.

"In addition to being a first-class visitor attraction, it will support regional tourism and leisure industries, provide a wide range of educational and training courses and bring a number of employment and volunteer opportunities to the locality."