The SEA-Directive and the SEA-Protocol adopted to spatial planning—similarities and differences

The Member States of the European Union had to implement Strategic Environmental Assessment (SEA) by July 2004. Spatial planning is one of the main issues to be addressed by the SEA-Directive. In future, SEA in the EU Member States will have to be amended because of the UNECE-Protocol on SEA as soon as the Protocol will be ratified by sixteen of the signing States. This article compares the SEA-Directive to the SEA-Protocol and shows which changes will be necessary in the EU-Member States due to the Protocol. On the example of spatial planning in Austria, we estimate the expenses and benefits of the implementation of the SEA-Protocol in addition to the expected expenses and benefits of SEA according to the EU-Directive. From this survey, it can be concluded that SEA according to the EU-Directive can raise the transparency, traceability and quality of planning processes without causing major delays or expenses. SEA serves to promote preventive, integrative environmental protection in spatial planning. According to our results, the implementation of the SEA-Protocol will generate comparatively modest additional benefits that might be accompanied by quite high additional expenses.