Lake Võrtsjärv

Võrtsjarv is the largest lake within the boundaries of Estonia. Not considering Lake Peipsi on the Russian border, it surpasses all other Estonian lakes together by the surface area (270 sq km).

The lake depression is of preglacial origin but has somewhat been influenced by glaciers. The few islands are mostly located in the southern part of the lake. Tondisaar and Pähksaar are permanent islands while Ainsaar turns into a peninsula during low water, and Heinassaar is flooded in high water periods. Despite its large surface area, the lake is shallow (the average depth 2.8 m). The deepest place (about 6 m) lies between the eastern shore and the island of Tondisaar along the submerged elongation of the riverbed of the Väike Emajõgi River.

The shores of Võrtsjarv are mostly low: swampy in the southern part, and sandy in the northern part; the eastern shore is higher. On the eastern shore the Devonian sandstone bedrock is denuded along a stretch of several kilometres.

Võrtsjärv has tens of inflows collecting their water in three counties, on a catchment area exceeding the lake surface twelve times. Väike Emajõgi, Õhne, Tarvastu, and Tänassilma rivers are the largest inflows. Suur Emajõgi is the single outlet; however at times in spring when dammed up by a mighty flood from the Pede River 5 km downstream, the river starts flowing back towards the lake. During such a period (on the average two weeks a year) Lake Võrtsjarv is devoid of any outflow. As a result, the high waterlevel usually lasts for several months in spring, while even the rise in autumn can be noticeable. The mean annual difference in the lake volume between the high and low water level can be threefold.

36 fish species occur in Lake Võrtsjärv. Pike-perch, eel, bream, and pike are the most important commercial fishes while perch and roachare also abundant. In the fifties and sixties Võrtsjärv was known as a ruff lake since inferior fish prevailed in catches. After the application of measures proposed by scientists of the Limnological Station (ban on trawling, strict fish protection, introduction of glass eels), big and valuable fish species became dominating. The total yearly fish catch averages over 400 tons in Lake Võrtsjärv, with the share of valuable fish 60-70%. The negligible natural eel have been caught in some years.

Lake Võrtsjärv area comprises seven rural municipalities bordering the water, connected with each other by traditions of joint activities, set throughout history. The development of Lake Võrtsjärv and its vicinity, and planned utilisation of Lake Võrtsjärv as a resource, is the common interest of all rural municipalities. The mentioned rural municipalities are located on the territories of three different counties:

Rannu and Rõngu - in Tartu County;

Puka and Põdrala - in Valga County;

Tarvastu, Viiratsi and Kolga-Jaani - in Viljandi County

//Source: Võrtsjärv Travel Guide; 2006