Vranov Dam

Pearl of the national park Podyjí

History of the Vranov Dam – the river Dyje caused many floods in the past and was destroying all that was in its way. The only solution to the problem was building a dam whose concrete walls would keep hundreds of cubic meters of water which could also be used in the power station inside the dam to produce electricity.

The first idea to build the dam at Vranov nad Dyjí came up as early as before the 1st world war. It was a project of a student (Mr.Schmidt´s – a Vranov native builder´s son) and his schoolmates at the Swiss Technical University of Architecture presented during the summer holiday of 1903.

The project of using water power in the Dyje river was first discussed by the Podyjí plant called Thayawerke in 1912. It was rather daring project for Morava region and there weren´t any funds for such a big construction in the Austrian-Hungarian Monarchy at that time either. After establishment of the Czech Republic in 1918 Podyjí plant agreed that the main investors would be the state and the Moravian-Silesian lands supported by the West Moravian power plant joint stock company.

Three joint stock companies were commissioned to build the Vranov Dam in 1929. Czech-Moravian company in Prague, company Lanna in Prague and Pittel und Brausewetter in Brno. The project was worked out by the Municipal office in Brno and in the course of the construction itself it was updated by new pieces of knowledge gained from other dam constructions built abroad.

Construction of the valley dam (on the Dyje river) at Vranov nad Dyjí (the biggest water plant in ČSR at that time) started in March 1930 together with construction of new Bítov, two bridges and road system in new Bítov and it was all lead by the chief regional building counselor – Ing. Karel Navrátil. 2 500 workers were working on its construction and it was completed in 3,5 years – in the autumn of 1933 when the reservoir started to be filled with water. Its operation started in 1934.

The capacity of the dam is cca 150 mil. m3. The dam also receives water from the Želetavka river which flows into the Dyje near the Bítov Castle. The reservoir reaches as far as 1,5 km under Podhradí nad Dyjí. The total length is 30km, the deepest spot (46m) is right next to the dam wall and under the first bridge at Bítov it reaches about 30m. The area of the surface of the reservoir is 763 ha and it is situated in 351 m above the sea level.

Brilliant construction – the dam wall of the Vranov Dam was built as a gravitational wall from poured concrete. Fundamental width is 27 m and it is narrowing towards the top which is 6 m wide. The top crown is 290 m long and the height above the foundation is 54 m. Bending radius is 500m. The wall was divided into three parts by two reinforced blocks both 27 m wide. Left and middle top parts are spanned with a bridge and are used as overflow for big water. On the left side there are cascades that serve for taking overflowing water from the left wing into the pit under the dam. The top overflows are 122 m long and their capacity is 580m3/sec. In the left side there are four outlet pipes with diameter 1600 mm which serve for releasing water at speed of 170 m3/sec. In the right side of the dam there are three pipes with diameter 2600 mm bringing water in the power station built at the bottom of the wall. The power station is equipped with three Francis turbines each with the power of 5,44 MW and with flowage 15 m3/sec. Because of regular inspection vertical shafts and three passage tunnels were made.

In 2002 the river basin of the Dyje suffered from big flood that was rated as anomalous and extreme and it is also called 500-year water. During this flood surfaces of concrete constructions were damaged at the airy and upstream side of the stone coating and on the side supporting walls of the overflow safety cascade. Then supporting walls in the pit and in the outlet from the power station were damaged. Substantial damage was also done to the construction and technological part of the machine room near the lower escapes.

All the damage together with the decision of the State organization protecting people and their property iniciated immediate beginning of repair work to keep this water work in good condition and to ensure its safe operation. Repair works comprising mostly of rescuing concrete constructions started in September 2003. The first part of repair in the extent of 7,6 mil CZK was finished in August 2004. The second part of repair represents larger work that is technically and financially more extensive and more demanding. According to the agreement with the construction supplier this period with financial requirement of 44 mil. CZK should be completed by the end of 2005. The final phase of repair which is currently in the stage of finishing the project documentation is planned to be completed in autumn 2006.

Ship Transport

Construction of the Vranov Dam was completed in 1934. Businessmen had the green light. Accommodation facilities and ships for passenger transport were built. Between 1934 -1992 the Vranov dam boasted with flotilla of 20 vessels. But they were gradually set aside.

Shipping club (Plavební klub) was the first operator of shipping transport. Ladislav Prchal and his ship „Lada“ were transporting people from 1935. In 1947 the businessmen united in the Spa and shipping syndicate of Podyjí. They had 8 ships and their most beautiful ship was a wheel steamboat “Mír” (Peace) which was festively christened on 14 August, 1949.

Also ship “Morava“ belonged among the steamboats and it was brought from Vienna during the war in 1939 (then called Starnberg). It was put onto the water surface on 11 August, 1946. It was one of the fastest and most beautiful Vranov ships. It was set aside in 1965. Another ship “J.Máša“, later renamed to, “Brno“ was set aside. There were other vessels such as quick ship “Prague“, passenger ship “Star“ (Hvězda), “Znojmo“, Hungarian hydrobuses “Dunaj“, “Dyje“, “Vranov“, and “Košice“. “Moscow” was the longest serving ship – it was festively christened on 20 June, 1981 and it served until 1992. Currently it can be seen in Prague in the landing place, it was renamed to “Moravia” and it is one of the most successful ships of Prague Vltava flotilla.

Municipalities of Vranov and Bítov and businessmen associated near the Vranov dam have been trying to revive this white flotilla. Unforgetable beautiful natural sceneries lining the banks of the dam from Švýcarská bay to Lančov bay, Chvaletice and to Bítov will enrich visitors´ experiences.

The footbridge at the Vranov dam is another dominating construction (bridge over the Švýcarská bay) built in 1992-1993 and it is connecting the beach with the dam.

Present

The Vranov Dam is currently used as a reservoir of drinking water and as an important recreational and tourist centre. The lake is surrounded by woods, beaches and weekend houses. It abounds with extraordinary natural sceneries especially deeply dug in meanders, rock cliffs and bizarre rock formations. There are mostly original leafy trees especially oak and beech and also coniferous such as pine, spruce and larch. This region is noted for extraordinary variety of plant and animal species. Climatic conditions are very favourable in summer when temperature exceeds 30°C and the temperature of water ranges between 20 - 25°C. Water in the lake is clear for the whole season and has no cilia. Scenic quiet corners of the Vranov Dam – Moravian Adriatic (as it is often called) attracts thousands of visitors from home and abroad.