In 2004, Ukraine decided to commence the execution of the deep sea channel construction on the Chilia and Bastroe branches without notifying Romania, considering that the project had no transboundary implications, although the Investigation Commission that carried out its activity between 2005 – 2006 identified several possible transboundary effects such as impact on the hydrology of the area, causing disturbances to the fish habitats and impacts on bird habitats as a result of the dredging and construction works in the area. The Investigation Commission concluded that the identified impact will continue subsequent to the implementation of the Ukrainian channel (during the exploitation period), therefore it was recommended to elaborate and implement a plan for monitoring the present and future effects of the Bastroe project. The studies elaborated in 2008-2009 revealed significant changes in the hydrological regime on the Chilia branch after 2004, which confirms one of the conclusions of the Investigation Commission.
Consequently, in 2013 it was necessary to prepare a study regarding the monitoring of the quality of physical-chemical and biological components from the Danube Delta and the adjacent coastal area in the context of the transboundary impact produced by the Bastroe Channel. The data provided by the continuous monitoring of these components helped to substantiate Romania’s position in the Romanian-Ukrainian bilateral meetings as well as in the meetings of the Espoo Convention regarding the transboundary impact of the Bastroe Channel, providing an overview of the monitored effects of the deep-sea navigable Danube-Black Sea channel, constructed by Ukraine in the Danube Delta.
For the characterization of the water factor the following parameters were analyzed: hydrological regime and hydrology of the Chilia branch by comparing the period between 1995-2002 with the 2004-2012 period, water chemistry in the Danube Delta and the adjacent coastal area and the morphological changes in the area (Danube Delta, Chilia branch, Romanian coastline of the Black Sea), due to the execution and activities carried out on the deep-sea Danube-Black Sea channel.
To determine the biological (hydrobiological) quality, researches regarding the status of habitats in the adjacent delta and marine areas were performed for the following biological components: phytoplankton, macrophytes, zooplankton and aquatic macro-invertebrates. Also, various investigations were carried out on the dynamics of fish populations, bird populations and species of amphibians, reptiles, mammals considering the impact of the disturbing factors in the study area, and also regarding the conservation status of habitats (feeding places, reproduction, etc.).
Considering the wide range of information available, various ecological effects were anticipated for the Romanian Danube Delta, corresponding to the competence area of the Danube Delta Biosphere Reserve as well as to the neighboring marine region