Comprehensive water resources planning is an essential initiative activity due to the long-lasting impact on social, economic, and environmental aspects. The Analytic Hierarchy Process (AHP) is one of the popular multi-criteria decision-making tools for the measurement in water resources planning. However, the AHP’s ratio scale is not appropriate to measure shortlisted candidates as it exaggerates the difference of paired objects. This paper proposes the Primitive Cognitive Network Process (PCNP) as a promising alternative to support decision making in water resources planning. To demonstrate the usability and applicability, an established case with the Analytic Hierarchy Process (AHP) to measure the profitable use of the storage reservoir is revisited by the PCNP. Comparison results are discussed. The PCNP can be integrated with the other methods to be applied to the other application domains in water resources management and planning.