Vancouver Aquarium has outlined ambitious expansion plans for the next 12 years, which include the eventual phase out of its captive beluga programme.

The aquarium was left reeling last November when two of its whales died in quick succession, with Aurora and her daughter Qila dying just days apart, leaving the facility with its signature tank empty.

As part of the CA$100m (US$76.1m, €72.2m, £61.3m) expansion, the aquarium is building a larger enclosure for its Arctic beluga habitat, with a new water filtration system and improved security measures. Up to five belugas currently on loan to other facilities are expected to be on display by Q2 2019, though they will be non-breeding animals. The aquarium says it will no longer house whales by 2029 – the year the facility’s operating license expires.

“The aquarium has announced a new 12-year beluga conservation programme centred on a small group of non-breeding beluga whales that will be brought back to Vancouver from peer accredited institutions to participate in an expanded Marine Mammal Research Programme,” said the aquarium in a statement.

“By the end of 2029, the aquarium intends to discontinue its display of beluga whales, and this proactive and important on-site conservation research programme will come to an end.”

Beyond 2029 the aquarium says it will continue to work with belugas, but that its conservation work would continue “further afield”.

A ruling by the Vancouver Park Board banning the breeding of captive cetaceans collapsed in November 2014, when it tried to push the ruling through at the last minute.

Following the deaths, Park Board chair Sarah Kirby-Yung – former vice-president of communications for the aquarium – said that the events justified a vote by city residents on continued whale captivity in the region, adding at the time that she would be making a proposal to the board for this vote as part of the upcoming 2018 municipal election.

The aquarium owns six belugas, four of which reside at SeaWorld in Orlando, with the remaining two calling Georgia Aquarium home. Including the recent deaths, the aquarium has lost three belugas since 2015, with a beluga – loaned to Orlando SeaWorld from Vancouver Aquarium – dying after an encounter with other animals in its tank in February 2015.