Goczałkowice Reservoir

Beneath the surface of Goczałkowice Reservoir lies the centre of the former village of Zarzecze, church and all, along with the historic border between Upper Silesia and Cieszyn Silesia. Filled in 1956, this reservoir on the Vistula covers up to 32 km² and is today one of the main sources of drinking water for the Silesian conurbation. You cannot go into the water, but the 2,980-metre dam crest and the dykes of nearby fishponds offer views of one of the most important bird sites in southern Poland.

History: water for industrial Silesia

The idea of a reservoir on the upper Vistula resurfaced from the early 20th century, and in the 1920s it was championed by Gabriel Narutowicz, later Poland's first president. The rapid growth of the Upper Silesian Industrial Region and the threat of water shortages settled the matter after the war: studies began in 1947 and construction ran from 1950 to 1955. Part of Zarzecze was flooded — around 2,000 residents from 428 farms were resettled. The work was rushed: old flood embankments, tree stumps, reinforced-concrete bunkers from World War II and the abutments of an old bridge were left in the basin.

The reservoir in numbers

The dam at Goczałkowice-Zdrój is about 2,980 m long, and the reservoir holds around 168 million m³ of water. Despite its size it is shallow — the average depth is about 5.3 m, and the water level can vary by several metres, changing the shoreline considerably. It is managed by the Upper Silesian Waterworks Company (GPW) and supplies about 38% of the treated surface water the company distributes, while also providing flood protection and supporting fisheries.

Birds

Surveys from 1983–2004 recorded 258 bird species on and around the reservoir, 113 of them breeding. Breeders have included the purple heron, ferruginous duck, whiskered tern and avocet, which in 2002 raised only the second successful brood ever recorded in Poland here. During migration, up to 2,000 cormorants, hundreds to several thousand bean geese and as many as 10,000–40,000 mallards gather. The entire reservoir lies within the "Upper Vistula Valley" Natura 2000 site, and the nearby fishponds host the country's largest breeding colony of black-crowned night herons.

Tripto tip

The reservoir itself is a no-entry zone, so don't plan a beach day or a walk along the shore. The best starting point is the dam crest — a walking and cycling path linking Goczałkowice-Zdrój with Zabrzeg; allow about 40 minutes one way on foot. Birdwatching is easiest from the avenue through the Bór woodland between the Maciek and Zabrzeszczak ponds. Spring and autumn migration bring the most activity; bring binoculars and stay on marked paths.