Agro-pastoral dams (APDs) are an increasingly popular method of adaptation interventions improving communal water supply in rural West Africa. However, APDs are often constructed in areas where culturally heterogeneous pastoralists and farmers compete for similar land and water resources. Lifting open access water abundance is likely to change if not intensify ongoing tensions between farmers and settling Fulani herders. The extent of collective action and inclusivity of 6 APDs in Northern Ghana are analysed, combining theory from common-pool resource management and equity and justice in climate change adaptation into a proposed Inclusive Collective Action (ICA) model. Practically, the article demonstrates that neither fully excluding Fulani pastoralists nor making dams openly accessible results in inclusive APD usage and management where collective action is successful, and more dynamic forms of regional inclusion and exclusion are needed. Theoretically, the article identifies some of the limitations of applying the enabling conditions for collective action of common-pool resource theory as it tends to overlook negative aspects of excluding certain user groups in culturally heterogeneous contexts from managing and using a commons.