Joints form a bridge between the fixed road surface and the road surface of a viaduct or bridge. They cushion the contraction and expansion of the viaduct and protect the underlying structures from moisture and de-icing salt during winter. However, in practice the Directorate-General for Public Works and Water Management (Rijkswaterstaat) does not always correctly construct joints optimally and/or maintain them optimally. As a result, the joints may leak, causing damage to the underlying main supporting structure and bearings. This may ultimately lead to the viaduct having to be replaced prematurely. This study identified and compared the social impact of optimal versus suboptimal maintenance over the entire lifecycle of the viaduct. These include effects on finance, the environment and traffic flow. The main conclusion is that optimal maintenance is very worthwhile from a societal perspective. The extra maintenance costs are much lower than the consequential damage that occurs if a viaduct has to be replaced prematurely.