APA Group (ASX:APA) has referred the Queensland and New South Wales sections of its proposed Bulloo Interlink Pipeline for Commonwealth environmental assessment under the Environment Protection and Biodiversity Conservation Act, advancing stage three of its East Coast Gas Grid expansion, according to a Thursday statement by the company.

The underground pipeline will link the company's South West Queensland Pipeline with the Moomba to Sydney Pipeline, creating a more direct gas transport route and boosting north-to-south capacity by about 30% to help meet expected southern gas shortfalls from 2028.

The company is advancing environmental studies and design ahead of a final investment decision later this year, with construction planned for 2027, subject to approvals, and completion targeted for 2028.