The state as a stimulator of wastewater treatment policy: a comparative assessment of three subnational cases in central Mexico

River basin management and decentralisation reforms are promoted worldwide for solving water pollution problems. In Mexico, governmental efforts have been made to operate wastewater treatment plants countrywide, but federal administrations have not achieved their intended outcomes. Acknowledging the role of governance in the implementation of wastewater treatment policy, this paper analyses three cases in central Mexico and addresses the question: How does the governance context affect the implementation of the wastewater treatment policy in central Mexico? A governance assessment tool is applied to answer the question. The assessment allows an understanding of the governance context and is paired with a comparative case study design. Data was collected through semi-structured interviews and documents reviews. The results indicate that the governance context mainly restricts the implementation of the wastewater treatment policy. In all subnational three cases, the river basin management and decentralisation reforms have not reached their objectives. By comparing the three cases, we found that the state level can play a relevant role to decrease fragmentation and to increase the coherence of the wastewater treatment policy. Therefore, strengthening the involvement of the state government and the improvement of mechanisms that limit political machinations can increase the supportiveness of the governance context.