City of Calgary Composting Facility

The Calgary Compost Facility is the largest in-vessel composting facility in North America, with the main composting building having a footprint more than 31,000 square meters. The facility is designed for a minimum annual processing capacity of 45,000 wet tonnes/year for dewatered biosolids and 100,000 tonnes/year for Source Separated Organics (SSO).

The plant, along with all related infrastructure, handles composting for anaerobically digested and dewatered biosolids from the City’s wastewater treatment plants, and food scraps and leaf and yard waste from single-family households (SSO).

The functional program areas include a tipping floor/receiving area for organics intake, a shredding area, sealed in-vessel concrete composting tunnels with underfloor aeration and sprinklers, a large biofilter for odour control, screening, curing building and storage building.

This is the first commercial building in Alberta registered under LEED^® v4, with several sustainable design features that complement its function. For example, the composting process uses a significant amount of water. Instead of using City water, 100% of the site storm water is recovered and used, which also relieves strain on the sewer system in heavy rainfall.

Public education is also part of the program, with a classroom looking into the composting facility and an outdoor learning garden. Here, Calgarians can learn about the positive impact that composting has on local environmental conditions.