Lake Lebyazhye: renovation from Kazanorgsintez
By the summer of 2017, Kazanorgsintez is planning to restore one of the favourite recreation places of the residents of the city — Lake Lebyazhye
In August of this year, the President of Tatarstan Rustam Minnikhanov gave the order to start the works on improvement of facilities of the forest park Lebyazhye in the framework of the Year of the water protection zones in Tatarstan. At the ceremony, he stated that this project involves the restoration of the lakes that existed here before and thanked the designers and ecologists who carried out the pre-project works, as well as TAIF JSC and Kazanorgsintez PJSC that will implement the main part of the program. 'I am confident that by next year we will have real solutions, the lakes will be restored. We are planning to restore all the lakes, which existed, and to improve the adjacent territory,' said RT President. Reanoe Vremya decided to find out how exactly the reconstruction of water reservoirs will be carried out.
Endangered lakes
Located 12 km away from Kazan city centre, the Lebyazhye lake system, where once there was a network of camps and lodges, included four lakes: Maloe Lebyazhye, Bolshoe Lebyazhye, Svetloe Lebyazhye and Sukhoe Lebyazhye. The area of the lakes was 42,9 ha, water volume — 586,000 cubic meters. But now only Maloe Lebyazhye hardly can be called a lake.
According to the conclusion of the Department of environmental engineering and water management and of the laboratory of water ecosystems optimization of the Kazan (Volga region) Federal University, the depth and volume of lakes have decreased by half and now they are drying up.
Lake Svetloe Lebyazhye represents narrow and shallow wetland channels. Sukhoe Lebyazhye has completely dried up and overgrown with trees.
In the absence of sources of replenishment with water, the lakes may disappear completely within 10-15 years. The problem is that these lakes are not charged with groundwater. The lakes are located above the groundwater level and fed by the catchment area. They exist only due to the fact that in spring they are filled with melt water and in the summer – with rain water. But in the 1990s and 2000s, due to the reconstruction of the Gorky Railway and the construction of the Gorky highway, a part of the spillway was cut. Eventually, melt water decreased two times.
No other options
Attempts to make the lakes full-flowing again have already been made before. Since 1995, the pumping of water through pipelines from the Yudinsky pit (Lake Izumrudnoe) to Lake Lebyazhye are carried out periodically. Lake Svetloe Lebyazhye received 1,200 cubic meters of water, the water level of the lakes rose to 1.5 m. In June of 1996, according to the Department of environmental engineering and water management and the laboratory of water ecosystems optimization of the Kazan (Volga region) Federal University, the lakes were pumped with 410 thousand cubic meters of water. During summer until September, in the lakes it is observed the water level close to normal. But the hydro-meteorological conditions affected the high evaporation from the lakes, so until the beginning of the 2000s, the pumping with water was carried out annually. For several years due to the water inflow from the Yudinsky pit, all the lake system was filled with water. However, in the early 2000s, the pipeline and the pumping station were dismantled, or, according to some versions, they were just stolen, and the lakes began to dry up again.
In 1998, the Institute of DAP/VODGEO (Moscow) in order to prevent loss of water developed a project on creation of a 'clay castle' on the bottom of Lake Maloe Lebyazhye. During the implementation of the project, it was made a pit at a depth of more than 4 m. This led to the violation of isolation of the lake bottom, the water just began to leave in the sand, on which it actually 'lies'.
Since 2004-2005, Lake Maloe Lebyazhye was added with water from artesian wells. Only due to that it still exists. But artesian water is highly mineralized. Because of the changes in the composition of the water, the flora and fauna of the lake have died, according to the conclusion of the Department of environmental engineering and water management of water ecosystems of the KFU. Artesian water is too hard in order to bred fish, to have seaweed. So, this source cannot solve the problem.
Virtually the only method of saving the lakes of the Lebyazhye system remains the restoration of the system of pumping water from The Yudinsky pit. 'People have already done so much that there are no alternatives,' says the Deputy Director General of Kazanorgsintez PJSC for capital construction and overhaul Alexey Blinov.
A pipe at first
This project has already been time-tested and showed good results. In the first phase, which began in September, it is planned to lay a pipe from Lake Izumrudnoe to Lake Svetloe Lebyazhye. The pipeline laying and the installation of a pumping station to pump water from Lake Izumrudnoe will be implemented by Kazanorgsintez. The cost of these works, according to Aleksey Blinov, is estimated at about 50 million rubles. Why was it chosen Svetloe? The level of bottom is the lowest point in the whole system of the lakes and in proportion to the water level increase in the lake water in a natural way will go in other lakes.
'In the spring of 2017, during the freshet, when the water is in excess, it is planned to pump into the lake more than 400 thousand cubic meters. Such volume of water can be pumped in about 3 weeks. If more water will be needed, the works will take about 4 weeks. It is possible that by 1 May all the lakes of the Lebyazhye system will be filled with water,' says Deputy Director General of Kazanorgsintez.
It is not decided yet what to do with bushes, which cover the lake, and how to strengthen the bottom, it is impossible to pump water in the lakes. It is necessary to carry out engineering-ecological and engineering-geological studies to determine the thickness water-retaining layer. 'This work is given at least 2 months, I think, by the end of October we will get the full picture and the time will not to be missed,' said Deputy Director General of Kazanorgsintez PJSC.