Alaska Airlines oversees many sustainability efforts as part of its goal to reduce in-flight waste per passenger by 70 percent by 2020. It recently added a new initiative to its efforts, christened #FillBeforeYouFly. The initiative urges passengers to bring a refillable water bottle on their flight and fill it before boarding. Plastic bottles are among the top most common items polluting the ocean, expected to contain one metric ton of plastic for every three metric tons of fish by 2025.

“We’re passionate about working with our guests, employees, airports, and partners to reduce waste, protect habitats and improve water health,” said Diana Birkett Rakow, vice president of external relations, Alaska Airlines. “Land, water and animals are incredibly special parts of the places we live and fly — and it takes many different company and individual actions together to protect them for the long term. This is just one step. If just 10 percent of our guests bring their own pre-filled water bottle when they fly and choose reusables, it could save more than 700,000 plastic water bottles and 4 million plastic cups per year. That’s a big lift.”

For every passenger who brings a pre-filled water bottle onto an Alaska Airlines flight and posts a photo of their bottle to social media tagging Alaska Airlines and using #FillBeforeYouFly, Alaska Airlines plans to plant a tree. The airline hopes to plant 1 million trees on the West Coast in conjunction with the Bonneville Environmental Foundation.