Looking to reduce its impact on the environment, San Francisco International Airport (SFO) is banning the use of single-use plastic water bottles later this month.

The ban, which goes into effect August 20, is an expansion of the airport’s Sustainable Food & Beverage program and also keeps SFO compliant with the City and County of San Francisco’s Plastic, Litter and Toxics Reduction Law.

“Airport tenants, vendors, and permittees may not provide or sell bottled water in containers that contain plastic or aseptic paper packaging, including in vending machines,” SFO informs concessionaires on its website. “Reusable water bottles, recyclable aluminum, glass and certified compostable water bottles can instead be provided or sold. Bottled water is defined as drinking water in a sealed box, bag, can, bottle, or other container intended primarily for single-service use and having a capacity of one liter or less. Drinking water includes purified water, mineral water, carbonated or sparkling water, and electrolyte-enhanced water.”

This past spring, the airport issued its Food Service Ware and FoodService Ware Accessories Requirements, encouraging tenants to use reusable food service ware whenever possible. SFO says tenants may only use single-use food service ware and accessories that are certified compostable by the Biodegradable Product Institute (BPI) or made entirely of natural fiber such as paper, wood, or bamboo, labelled, “compostable” with green color coding, and fluorinated chemical free.