Evolutionary Game-Theoretic Analysis of Rural Wastewater Treatment Projects

Abstract

To address the behavioral coordination challenges among government agencies, wastewater treatment enterprises, and village collectives in rural sewage treatment projects, this study develops a tripartite evolutionary game model to systematically analyze the strategic choices, payoff structures, and evolutionary stability mechanisms of these stakeholders. The research identifies the core interest logics of the three parties: enterprises' compliance decisions depend on cost differentials, subsidies, and penalties for non-compliance; village collectives' supervision is driven by supervision costs, rewards, and damage mitigation benefits; and government regulatory intensity is determined by regulatory costs and marginal governance benefits. The probability of detecting violations serves as the critical nexus linking all three parties, with synergistic efforts between government regulation and village collective supervision significantly enhancing the efficiency of violation detection. The stability of the ideal governance state (active regulation-compliant treatment-proactive supervision) requires meeting three threshold conditions: penalties and subsidies must cover enterprises' non-compliance costs; rewards must cover village collectives' supervision costs; and marginal governance benefits must cover government regulatory costs. The system exhibits eight boundary equilibrium points and mixed equilibrium points, where parameter changes and unilateral strategy adjustments by any single stakeholder trigger tripartite co-evolution, ultimately determining the convergence state of project governance. These findings provide theoretical foundations for policy design and mechanism optimization to ensure the long-term operation of rural sewage treatment projects.