Biebrza National Park is located in north-eastern Poland, in Podlaskie Voivodeship, in the areas of two districts: Grajewo and Mońki, three municipalities: Goniądz, Rajgród and Grajewo. The park was established in 1993 and is the largest national park in Poland. The park area is 59,223 ha. Forest areas in the park constitute of 15,547 ha, agricultural land - 18,182 ha, and the wasteland – the famous Biebrza marshes, in fact the most valuable natural ecosystems – 25,494 ha. Biebrza National Park protects a vast and almost unchanged valley peat bogs with unique species of plants, birds and other animals, and natural ecosystems. Biebrza Valley is a very important nesting, feeding and resting place for wetland birds, so in 1995, has been listed as habitat of RAMSAR convention, that is wetlands habitats of international importance, especially as a living environment of wetland birds. One of the biggest challenges and tasks the park has to fulfill is the improvement and restoration of water relations in Biebrza Valley together with the maintenance of the open non-forest ecosystems.
Over the past 150 years, local hydrographic relationships have significantly changed. The hydrographic network has been largely transformed as a result of nineteenth century canal digging and extensive drainage works in the twentieth century. Two big canals (Woźnawiejski and Rudzki) and some smaller ones (eg. Łęg and Kapicki) were created. For wetland ecosystems (that occurred in the area as a result of either the permanent flooding by groundwater, or effect of the annual, spring flooding), digging artificial canals meant a dramatic change in water supply conditions. This led to discontinuation of peat-forming processes and to degradation of peatlands, as a result of rotting and altered plant communities.
These adverse effects worsen, particularly in the vicinity of canals. The need to improve water conditions in this locality is found to be necessary in many research works of the area.
The work by W. Maleszewski from 1861 discusses how to create two main canals: Rudzki and Woźnawiejski, as well as minor canals: Kapicki and Łęg.
Maleszewski wrote: ‘For the drying of these marshes two main canals have been designed and constructed, in addition to numerous trenches. One canal, according to the project, was to have almost 9,433, to be 32 Warsaw feet* wide, deep at 10 feet - it was estimated at rs** 33,577. The second canal to drain the water from Jegrznia River, 10,120 pr.*** long, 24 Warsaw feet wide, 7 feet deep, with a gradient of 18 feet - was calculated at rs 13,397. Original cost estimates (Ger. Anschalgs) have been significantly increased, in order to make a full transition of the marshes into useful meadows.’
The Rudzki and Woźnawiejski Canals, which Maleszewski writes about, were built between 1845 and 1861, after the great famine in 1844, as public works. These canals were to facilitate the drainage of excess water from wetland meadows to allow access to those areas and facilitate hay cutting.
To ensure the livelihood of those living in Biebrza Valley the fields were also drained. This project marked the beginning of the process of using marshy grasslands for agricultural purposes.
Rudzki Canal, built in the nineteenth century, measures 16.7 km. It branches off from the Ełk River at Ruda village and flows into Biebrza River at Osowiec village, taking over the flow of Ełk River. The riverbed of Ełk (bumping previously to Biebrza at Wroceń village) between the branch at Rudzki Canal and the point of connection with Jegrznia River ceased to carry water from the upper part of the basin, becoming a dead riverbed. Hence the name of this part of the river – ‘Dead Ełk’. Jegrznia on the other hand, has become an independent tributary of Biebrza River.
Woźnawiejski Canal is 8 km long. It branches out from Jegrznia River, flowing into former river Ełka, creating a bow string made by Jegrznia and Ełk. However, it does not take over the entire flow of Jegrznia, that is in the case of Rudzki Canal.
Kapicki and Łęg Canals, located in the middle part of the Central Basin, have almost completely disappeared, due to lack of maintenance - in some sections it is difficult to find their original course.
* Warsaw foot = old Polish foot – until 1819; 1 Warsaw foot = 29.78 cm
** Up to 1897 there was a bimetallism system in Russia - a value of 1 rs (ruble by silver) was $0.76
*** pr. – so called pręt (Eng. rod)- old Polish agricultural measure of length; 1 pr. = 4.466 m