A COALITION of environmental groups says legal action launched against the builders of a dam in southeast Queensland could affect the proposed Traveston Crossing dam.

The lawsuit alleges that a fishway, built for the unique lungfish at Paradise dam on the Burnett River 80km southwest of Bundaberg, does not work endangering the species, which is considered a living fossil.

The Wide Bay Burnett Conservation Council has applied for an injunction against Burnett Water, the builders of the Paradise dam, requiring that the fishway be working within six months.

The conservation council's Roger Currie says the fishway, designed to protect the lungfish, has never worked properly and is not suitable and only six lungfish moved upstream using the fishway while none has moved downstream since the dam was built in November 2005.

He says the same fishway design is due to be installed at the Traveston Crossing dam if it gains approval from the Federal Government.

AAP