The manuscript should be revised according to the reply of the authors to the comments of the reviewers. The revised manuscript should not only describe the data and the direct conclusion related to the data of the three sites, but also discuss the possible impact for regulations and the transferability to other fields and regions. The reviews indicate that there is much more potential information in the data. A exhaustive data analysis and modeling exercise will not be feasible within one paper. However, the authors should give an outlook to future work and how their study fits in a broader scope of modeling and management with respect to nitrate transport.

The comments of the reviewers are addressed and the paper can be published subject to two corrections.
1. The second sentence of 3.1 .... average minimum .... average maximum ... should be ... minimum (yearly) average .... maximum (yearly) average .
2. in 3.5 the figure numbers 5 and 6 are interchanged, probably due to the new figure 5