Solution of environmental and climate issues remains relevant today. Since the signing of the Paris Agreements in 2015 many countries have begun to change legislative provisions and introduce new regulations aimed at reducing greenhouse gas emissions and reducing the environmental load on the environment. The authors pay special attention to the problem of disposal of municipal solid waste (MSW) and consideration of this process as a climate project. The aim of the study is to develop an economic model of MSW utilization and assess the economic effect of applying the mechanism of publicprivate partnership (PPP) on the example of the Novosibirsk region. The research method is a comprehensive simulation modeling with the use of assessment of investment projects efficiency. The model takes into account the possibility of providing containers for separate waste collection (SWC-containers) to all residents of Novosibirsk and the expansion of facilities for the collection and sorting of MSW. It is shown that the state support in the form of publicprivate partnership is crucial. Participation of the state in the project implementation contributes to provision of the city with a sufficient number of infrastructure facilities related to accumulation and utilization of MSW to reduce landfills and greenhouse gas emissions from them. The authors proposed to enhance the positive effect of the climate project by conducting an environmental marathon for the population. The expected results of the marathon were confirmed in practice.