In accordance with the Agreement between the Government of the Republic of Belarus and the Government of the Russian Federation on cooperation in the field of protection and rational use of transboundary water bodies, signed on May 24, 2002, the Vitebsk Regional Committee of Natural Resources and Environmental Protection together with organizations and departments of the Ministry of Natural Resources and of the Republic of Belarus in cooperation with the departments for the protection of water resources of Smolensk and Pskov regions of Russia For a number of years, the Yugoslav Federation has been working on the implementation of this Agreement.
The total catchment area of the Western Dvina within the Republic of Belarus is 33150 km2, the length of the river within Belarus is 338 km.
The river basin is formed by 12 thousand large and small rivers. Major tributaries: right – p. Toropa, p. Obol, r. Drys; left – p. Mezha, p. Kasplya, r. Luchesa, r. Ulla, r. Disna, p. Druyka.
The basin occupies almost entirely the Vitebsk region, capturing the northern part of the Minsk region (Krupski and Myadel districts). The territory of the basin. The Western Dvina includes 23 administrative districts.
On the territory of the basin there are 18 transboundary lakes and 10 transboundary watercourses, the flow of which flows into the territory of the Vitebsk region. According to the research results, possible sources of pollution of surface waters have been identified. Developed measures to prevent pollution of water bodies.
In general, the transboundary territory is characterized by a low level of economic development. The watersheds of water bodies are plowed up to an insignificant degree or not at all involved in economic activities. The lakes located within the study area are used mainly for recreational fishing, household and household needs of small (mostly rural) settlements, as well as a resting place for residents of nearby settlements.
In October 2018 in Smolensk, the twelfth meeting of the working group on the river basin took place. Zapadnaya Dvina, which summarized the work for the reporting period and defined tasks for 2019.
In the reporting year, the monitoring of water quality and the state of aquatic ecosystems of transboundary water bodies was continued. Water quality monitoring and assessment of the status of aquatic ecosystems in transboundary parts of the watercourses of the Zapadnaya Dvina River Basin are carried out at intervals of 12 times a year for hydrochemical indicators and once a year for hydrobiological indicators according to the sampling schedule.
During the reporting period, 24 hydrochemical samples were taken and 675 determinations were made.
The content of dissolved oxygen in the water of the water courses during the reporting period was recorded from 7.0 mgO2 / dm3 in r. Usvyacha in March to 10.3 mgO2 / dm3 in the river. The Western Dvina River in January was sufficient for supplying oxygen to river ecosystems.
According to the observations of hydrochemical parameters, the transboundary sections of the watercourses of the r. The Western Dvina is not subject to significant nutrient pollution. During the reporting period, the excess was recorded only in the content of phosphate ion in 8.33 percent of the samples taken. Excess for this indicator were recorded in the water of the river. Usvyacha in March (0.071 mgP / dm3, 1.08 MAC) and April (0.068 mgP / dm3, 1.03 MAC). According to other indicators (ammonium ion, nitrite ion, total phosphorus), values exceeding the quality standard established for them were not noted.
The increased metal content in the water of transboundary parts of watercourses is often due to their high natural background content.
During the year, the content of petroleum products in the water of transboundary parts of watercourses varied from 0.003 to 0.008 mg / dm3, not exceeding the MPC level. The content of detergents in water was also recorded within acceptable limits.
Additionally, over the past period, a hydrochemical survey of 5 transboundary water bodies in the basin of the r. Zapadnaya Dvina (Nishcha River, Ushka River, Obol River, Lake Ezerische and Usvyacha River), on the catchment of which 13 pig-breeding complexes were built, located in the Usvyatsky, Nevelsky and Sebezhsky districts of the Pskov region of the Russian Federation. Analyzing the overall hydrochemical state of the studied water bodies over the entire observation period (observations have been carried out since 2014), it can be noted that there are no steady trends in water quality changes under the influence of pig breeding complexes. However, it should be noted that over time the risks of pollution of water bodies will be aggravated due to the commissioning of all the complexes, the increasing load on transboundary watersheds.
In accordance with the work plan in July of this year, a seminar of laboratory services of the Russian Federation and the Republic of Belarus on the Dnieper and Western Dvina river basins was held in Klintsy (Russian Federation, Bryansk region) on the topic: “Ensuring the reliability of measurement results”.
Laboratory services conducted joint sampling and interlaboratory comparison analysis. An analysis of interlaboratory comparison tests showed that the test results of the participating laboratories for all identified indicators are correct and satisfactory, which is the basis for mutual confidence in the systematic observations obtained by the participating laboratories as part of the national monitoring programs of the Russian Federation and the Republic of Belarus.
At the meeting, the group considered the issue of water situation and the implementation of water protection measures at transboundary water bodies in the basin of the Western Dvina River. In the reporting period, research was conducted on the level and quality of groundwater. There was a regular exchange with the Russian side of operational hydrometeorological information, especially during the spring flood of 2018.
On the basis of the studies performed and a set of analyzes, a list of proposals for further joint research with the Russian side in the framework of the protection and rational use of transboundary water bodies has been developed.