In the light of growing water scarcity appropriate institutional arrangements are needed to complement technical interventions, in order to ensure more efficient use and allocation of water in agriculture. A theoretically interesting institutional intervention is the installation or improvement of water rights, but the benefits of such intervention and their distribution are insufficiently researched. This paper contributes to the water rights literature by applying a state-of-the-art valuation method to a case study in South Africa. Using a latent class choice modelling approach the heterogeneity in the benefits generated by changes in water rights is investigated. Two segments could be distinguished in the sample population. While one of the segments has a lot to gain from a water rights reform, benefits for the other seem rather limited. Furthermore they clearly differ in preference for specific improvements. Such considerations should be taken into account in policy design.