The Neretva (, ), also known as Narenta, is one of the largest rivers of the eastern part of the Adriatic basin. Four HE power-plants with large dams (higher than 150,5 metres) provide flood protection, power and water storage. It is recognized for its natural environment and diversity of its landscape. Freshwater ecosystems have suffered from an increasing population and the associated development pressures. One of the most valuable natural resources of Bosnia and Herzegovina and Croatia is its freshwater resource, contained by an abundant wellspring and clear rivers. Situated between the major regional rivers (Drina river on the east, Una river on the west and the Sava river) the Neretva basin contains the most significant source of drinking water. The Neretva is notable among rivers of the Dinaric Alps region, especially regarding its diverse ecosystems and habitats, flora and fauna, cultural and historic heritage. Its name has been suggested to come from the Indo-European root *ner, meaning "to dive". The same root is seen in the Serbo-Croatian root "roniti". Geography and hydrology The Neretva flows through Bosnia and Herzegovina and Croatia until reaching the Adriatic Sea. It is the largest karst river in the Dinaric Alps in the eastern part of the Adriatic basin/watershed. Its total length is , of which are in Bosnia and Herzegovina, while the final are in the Dubrovnik-Neretva County of Croatia. The Neretva watershed is in total; in Bosnia and Herzegovina with the addition of the Trebišnjica river watershed and in Croatia, . The average discharge at profile Žitomislići in Bosnia and Herzegovina is /s and at the mouth in Croatia is /s in addition to the Trebišnjica River's /s. The Trebišnjica River basin is included in the Neretva watershed due to a physical link of the two basins by the porous karst terrain. The hydrological parameters of Neretva are regularly monitored in Croatia at Metković. Sections Geographically and hydrologically the Neretva is divided into three sections. Its source and headwaters gorge are situated deep in the Dinaric Alps at the base of the Zelengora and Lebršnik mountains, specifically under the Gredelj saddle. The river source is at 1,227 meters above sea level and consists of five small and distinct wellsprings. On its 90 kilometers course through the first section the Neretva cuts two distinct deep and narrow canyons and two distinct wide and fertile valleys, around Ulog and then around Glavatičevo, before it