Many resource management studies focus on one resource. Humans, however, rely on multiple resources in a complicated way. A person may derive more well-being from one unit of a resource than from another; one resource may be substituted by another to some degree. How should one manage such coupled natural-human systems? In this work, we build on recent research that focuses on developing conceptual frameworks and mathematical models to understand such interactions. The multiple resource condition injects the concept of substitutability into models of coupled human-natural systems and affects how such systems should be governed. Substitutability has been mostly mentioned in the field of economics for a substitution of natural and human capitals. Similarly, one resource may substitute for other scarce resources in coupled human-natural systems since some of these resources are not completely independent. In this study, we revise and expand an existing conceptual framework to include two natural resources, resource users, governing agency and public infrastructure in a centralized governance structure, i.e., all the natural resources are managed by the same governing entity. We then devise a set of dynamical equations and relationships from different fields, such as a replicator equation, a population equation, and a CES production equation, to capture the dynamics of this coupled system. This analysis can provide a decision-support tool to design policies to sustainably govern the built environment where human, natural resources, and infrastructure are interconnected. Model analysis takes a multi-faceted perspective of both resource users and governing entities to assess policies against different levels of disturbance. The results reveal how substitutability and asymmetry in resource use affect the viable policies needed to maintain the system.