Springing from the Black Forest mountains in Germany and across eight countries and three capital cities, covering 2857 km, the Danube river, the second largest in Europe, concludes his journey form before its merger with the Black Sea, one of the most beautiful deltas in Europe and even the world. Length of the river is 2840 km, = 817.000 km water area.
Delta history begins 10,000 years ago, depositing a successive layers of silt that will clog the existing sea bay at the mouth of the Danube into the Black Sea, being forced to retire in the river bed. The marine sand and silt forming large sand banks, islands of the Delta, Letea, Caraorman Saltings St. George. The three branches are formed gradually, starting with the St. George arm (69.7 km), then Sulina (63.7 km) and ending with the youngest Chilia (120 km). Between these branches have formed a lot of natural links, channels and lakes, which, at the favorable river could cross the entire Delta. Delta’s total area is 5800 km ², including Razelm Sinoe lagoon complex.
Tulcea is the gateway to the Danube Delta. Built on seven hills, this former market town is now an important sea and river port, and most important center of fishing industry in Romania.
Danube Delta lies at the crossing parallel 45 º North latitude and longitude meridian 29.
Area: 5640km ² 4470 km ² in the Romanian territory. The area is relatively flat, with a slope of 0.006 ‰, permanently or temporarily covered with water at a rate of 70-80%. It looks like an equilateral triangle with sides of about 80 km long. At a rate of 5000-9000 m³ / s, transport annually, on average, 50 million silt (about 8 times more than the Tiber, 20 times more than the Rhine).
Land surfaces of the delta have two characteristics: they are arranged without apparent order and shows the heights of their small values. Grindul Chile is the maximum height of 6.5 m near the western village of Old Chilia. Dunes of sand bank north Letea reach an altitude of 13 m. Some islands in the lake are IDE support, for example, the Churches have four feet, but others are higher: Gradiste 19 m, 49 m Popina, thus surpassing the heights seen between the arms of the Danube.
The main rivers are the four arms of the Danube flows into the sea are:
CHILIA – the northernmost and most active arm with two branches and a micro-delta own. Length of 105 km to the Periprava, width: 1000m, maximum depth: 39m.Transporta about 60% of all river water, navigation of local interest. Between the city and the Danube Isaccea Chilia south shows a lot of small islands, which make him share in quiet water stripes, scattered on the sides.
TULCEA – arm which lies between Chile and St. George (on the right bank, Tulcea). Length: 19 km, width: 300 m Maximum depth: 34 m upstream of the port of Tulcea, the arm with the same name has a wide bed, as would leave free water to form a lake. At about 7-8 km from the port of Tulcea is himself the “head” of the delta, considered the most important point in the region geographically. It is the place where the Danube divides his water for the first time, the arms being Chilia and Tulcea. It carries about 40% of the river, winding coefficient: 1.40. Shipping way.
Sulina – the shortest, straightest and most developed arm. Length: 64 km width: 250 m, maximum depth, 18 m separation from water Ceatalul Tulcea Sulina field is analogous to that of Chile in Pardina water arm. Tulcea waters separating final. The two “new” arms so created, Sulina and St. George, but do not meet each flow to the river mouth in his own bed each one unique.
It carries about 22% of the river water, river and sea traffic channel (the obligatory minimum depth of 7.32 m, 7000 ton ship can move).
SFANTU GHEORGHE – the oldest branch of the Danube flows into the sea. Length: 64 km width: 550 m Maximum depth: 26 meters. The southern arm of Saint George is held group Razelm-Sinoe lakes, forming together with the area of swamps and ridges surrounding the basin and a morphological whole. It carries about 22% of the river, winding coefficient: 1.60. Navigation of local interest.