The aim of the study visit in September 2019 was to present and discuss Estonian RETROUT project sites where restoration works are planned.\u00a0In addition, examples of previously constructed fish passes were visited and critical aspects of\u00a0fish pass designs were presented.<\/p>\n
Linnam\u00e4e hydropower station<\/strong>, situated\u00a0on the lower stretch of the J\u00e4gala River,\u00a0was originally built in 1922-1924. In 1941\u00a0it was partially destroyed and only in\u00a02002 restored to present state.\u00a0Linnam\u00e4e is the most powerful hydro-electric power station in Estonia. It is 11 m high and its capacity is 1.1 MW.\u00a0 There is no fish pass and it is\u00a0deemed as a culturally valuable site.\u00a0The dam lost its water permit in August\u00a02019 and the obligation to provide fish\u00a0passage stands. The main discussion on the site was related to conflicting interests\u00a0regarding the site. Part of the dam was classified as culturally valuable and therefore optimal\u00a0solutions for fish passage are hard to achieve.\u00a0RETROUT project will provide plans how to remove the dam in a way that the cultural value is\u00a0least affected. This work is currently in process.<\/p>\n Kotka dam<\/strong> was built in 1950 and operated as hydropower station until 1960. After that it\u00a0provided water for a fish farm. The dam broke down in 2016 and it was not restored because\u00a0it has no water permit. The dam was 3.5 m high originally and its capacity was 200 kW. The main discussion on the site was related to the cost of different proposed solutions. Secondly, it is evident that several local people are not satisfied with a\u00a0loss of the lake and it was discussed how to communicate the solutions better so that the\u00a0local community would appreciate the activities. N\u00f5mmeveski power station<\/strong> was built in 1924 and operated until 1964. The wooden\u00a0components broke down in 2010. Characteristics: the remaining height of the dam is 1 m.\u00a0Since 2000 current owners of the dam have tried to get water permit to restore the\u00a0hydropower station. The site does not have major conflicting issues. The step under the\u00a0bridge cannot be lowered because the bride structures could become unstable.\u00a0In frame of the RETROUT project the plan is to\u00a0build 30 m long artificial rapid downstream from\u00a0the bridge, enforce banks and deepen the\u00a0concrete bottom under the bridge.<\/p>\n Other sites that were visited were the Joaveski hydropower station, Arbavere dam, Tapa fish pass, Kunda hydropower station, Old Kunda manor mill, Aravuse fish farm and hatchery and Sillaoru hydropower station.<\/p>\n
\nIn frame of the RETROUT project two alternative solutions have been elaborated. Both include the remoal of the dam construction, but according to one solution a 76 m artifical rapid will be created (more expensive solution) or only the banks will be enforced.<\/p>\n