The construction of the Pelješac bridge has been one of the most significant infrastructural endeavours in Croatia in the last several decades. Due to the type of the project, according to the EU and the national legislation it was subject to environmental impact assessment, which provided a framework for the environmental monitoring plan. To fulfil the requirements related to the monitoring of the marine environment the unique monitoring system was set up consisting of three modules: (i) two autonomous measurement buoys providing continuous near-real time data on water quality and meteorology with alarm function; (ii) measurements of water quality parameters in broader project area every two weeks; and (iii) monitoring of biological parameters. The measurements on buoys included water quality parameters on surface and 4 depths. The measurements on 8 stations in broader project area were performed by a multiparametric probe for measurements of water quality parameters on surface and at every 5 m depth up to the bottom, as well as measurements of optical characteristic of water. Monitoring of biological parameters included analyses of composition of the phytoplankton community, macroalgae (CARLIT method), Posidonia oceanica (POMI index) and benthic invertebrates, including invasive species.

bridge construction; marine environment; monitoring