Among several types of natural risks' protection measures, check dams are the most dominant in French mountains. Over their lifetime and while being subjected to severe phenomena such as torrential floods, the check dams' efficacy will be affected and therefore the level of protection provided by these structures will be reduced. Available budgets oblige risk managers to establish priorities between different maintenance strategies to be applied on structures that require maintenance. Modeling the dynamic deterioration of check dams and making decisions on their maintenance always depend on the amount of available data, diverse sources of data, assumptions, etc. This paper focuses on assessing the influence of uncertain inputs on the outputs obtained from a check dam's deterioration and maintenance model. The end purpose of such analysis is to support check dams' maintenance decision-making under the effect of information imperfection.