Relevance of some criteria for sustainability in a project for disconnecting of storm runoff

This paper evaluates the relevance of different methods and criteria for choosing the best technical system to solve a combined sewer overflow problem in a catchment in Oslo. Two systems are evaluated; namely conventional, or nature based. A discussion of different criteria and rough numerical calculation of these are done. It is shown that the nature-based alternative has the best sustainability with a good degree of robustness. The LCA method was found to be too comprehensive and complicated in the present situation, compared to the benefits one will get. A simple EIA analysis with a pragmatic choice of criteria was found most suitable.