Background One of the few remaining freshwater estuaries in Europe is to be found on the River Elbe. This includes a 64 km stretch that is subject to tides. The inconspicuous Oenanthe conioides, a flowering plant with a total population of 2 200 individuals, is endemic to the Elbe estuary, found here and nowhere else in the world. However, the presence of the great port city of Hamburg in the middle of the estuary means that Oenanthe conioides and its habitat face significant challenges. Objectives By re-opening an area of meadows beside the Elbe between Hamburg and Geesthacht to tidal influence, the LIFE-Nature project intends to breach an existing dyke to create new habitat for Oenanthe conioides. Although it is not yet found on the meadows, it is expected to stand a good chance of quickly establishing itself once the dyke between the meadows and the Elbe is breached. Cnidion dubii riverside meadows are also expected to reappear on 6 ha of the site and a tidal riparian woodland on 12 ha. Fish (Coregonus oxyrhynchus) and birds (Crex crex, Botaurus stellaris) are expected to follow. The whole ecosystem is to be based on the dynamic natural movements of the Elbe and will require no further human intervention after the massive construction works are completed, so that this project should have long-lasting results. The future reedbeds, sedges and riparian woodlands, together with the existing inland dune, will be an unaccustomed sight in the suburbs of a large city. Given the social context, this project intends to ensure appropriate public presentations and consultations. There will also be cooperation through networking and transfer of knowledge with similar dyke-opening projects. Results The LIFE-project ended in December 2006 without success. The main project objective, the creation of new freshwater tidal habitats, has not been achieved, since the planning permit was not obtained. The main reasons for its failure appear to be related to the high complexity of the planning procedure and to the lack of acceptance of the planned actions by some of the stakeholders. The main controversial issue for the planning approval procedure was the assessment of possible negative hydrological effects on buildings of neigbouring residents and companies. The beneficiary has provided extensive hydrological studies on this issue, which were questioned by local opponents of the LIFE-project. This resulted in considerable delays to the planning approval procedure. The beneficiary is still confident and willing to continue the project with unchanged objectives and without LIFE-funding. Its financing will be secured through a regional compensation scheme, without any intervention of European funding. In the short term the beneficiary intends to establish low-intensity grassland management methods in order to create hay meadows and Cnidion-meadows. However, the conservation benefit will be much more limited compared to what was foreseen in the original LIFE-project.