Zero Waste by 2030: A system dynamics simulation tool for stakeholder involvement in Los Angeles’ solid waste planning initiative

This paper describes a strategic level simulation model developed to help stakeholders understand the Los Angeles solid waste system. The model structure is based on a “recycling loop” incorporating five interconnected sectors: consumption, collection, processing, disposal, and production. The user interface includes eight strategic decision levers (product durability, waste in products and packaging, recycled content of products, product recyclability, consumption, consumer diversion rates, diversion processing capacity, alternative disposal capacity) and shows six output measures (waste sent to landfill, material diverted, diversion rate, relative greenhouse gas emissions, relative cost, and relative effort). Model analysis shows that maintaining the status quo erodes diversion rates, reducing upstream inputs to the waste stream (by reducing consumption, increasing product durability, increasing recycled content of products) yields the greatest improvements in waste reduction and lower greenhouse gas emissions, and that achieving desired changes with downstream levers requires using several levers in combination. The model also shows significant tradeoffs between reducing waste and the relative costs and effort required.