Prague suburban landscape development was demonstrated on one of the sewage conduit extensions. The impacts of the construction were assessed using the original method of environmental vulnerability and development feasibility. Specific problems of historical heritage, geological, hydrological and biotic aspects of the problem are assessed in detail using multidisciplinary evaluation of the critical factors. The feasibility of the project is estimated from the possible risks of the impact, that the construction might have, both during the implementation phase and upon its completion. These risks are satisfactorily solved by conditions stipulated in the study of biota, air and noise pollution and historical values, which make part of the EIA procedure. The most sensitive area will be protected by using tunnel construction of the sewage conduit.