Fourth Study Conference on BALTEX Scala Cinema Gudhjem

of snow deposit and snow cover are additionally being
carried out. 36 stations operate on the small rivers with
the catchment area about 500 км 2 and less. 67 posts are
involved in operative information exchange.
The main task of the hydrological monitoring
network is the reception of information on presence of
resources of surface waters, their geographic distribution
and variability in time. The information about
frequency of high waters and droughts are in particular
important in this context. The minimal density of
hydrological posts for the flat Byelorussian territories
should be 1 station per 1875 км 2 , according to
recommendations of the World Meteorological
Organization (WMO). The present density of
hydrological posts in the territory of Belarus is 1 station
per 1945 км 2 . Therefore, in order to meet the
recommendations of WMO Belarus should operate at
least 111 hydrological posts.
Along the main streams of the big rivers there should
be enough of hydrological stations for the purposes of
interpolation of water discharges between stations. It is
necessary to note, that the hydrological network of
Belarus corresponds to related requirements of WMO.
But there is a problem concerning observations on small
rivers. According to recommendations of WMO the
station density of hydrological posts should be equal for
small and main rivers. Water discharge of small rivers
may be highly influenced by local factors. Absence of a
monitoring network is felt very sharply even on rivers
with catchments areas of 10 км 2 and less for high
industrial developed regions where the smallest rivers
are important.
3. Hydrochemical monitoring network
The hydrochemical monitoring network includes 129
monitoring sites in rivers and 25 monitoring sites on
lakes. The distributions of a river monitoring stations in
Belarus due to EUROWATERNET (EWN)
classification is presented in table 3. The area of Belarus
is 207,6 thousands km 2 . The requirement of
EUROWATERNET is one monitoring river station per
1 thousands km 2 . Due to this requirement in Belarus
should be about 208 monitoring stations.
Table 3
Target number of station due to the EWN
requirement
208
Number of rivers/tributaries 55
Total Number of stations 129
Number of representative (R) 129
Number of reference (B) 0
Number of largest (L) 77 (incl. flux)
Number of flux (F) 10
No stations on small rivers 2
No on medium rivers 10
No on large rivers 26
No on very large rivers 14
No on largest rivers 77
There appears to be a rather even geographic
distribution of stations across the country but there is
still a higher station density at the largest rivers in the
regions/catchments of the country.
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A major concern is the station division into upstream
and downstream stations. The downstream stations may
be perfectly representative of urban pressures but they
need to make sure that they are not in fact “Impact
stations”, lying in the mixing zone of point sources.
Taking into account the complexity of this question and
necessity of additional researches all these stations
should be related to the representative stations in this
stage. If the present deficit in station density will be
improved following the requirements of EWN-basic,
stations at smaller rivers and in other sub-catchments
should be selected as reference stations to get a
representative overview of all rivers in Belarus – at
present the station distribution is biased towards the
largest rivers.
The requirement of EUROWATERNET for the
density of the basic hydrochemical monitoring network
in lakes is one monitoring lake station per 1750 km 2 .
Due to this requirement, taking into account the total
number, size and distribution of lakes, there should be
118 lake monitoring stations in Belarus. Therefore the
amount of lake monitoring station in Belarus is presently
not adequate for a representative assessment.
In the future, the surface water monitoring
(hydrological and hydrochemical) in Belarus requires an
increase of the station density in particular on small
rivers, and also the establishment of transboundary
monitoring. The implementation of improved
technologies is also important.
References
State Water Cadastre. The annual data about quality of
surface waters (for 1990-2002),2003
National System of Monitoring Republic of Belarus.
Results of observations for 2001 year. Annual
report. Minsk 2002.
World Meteorological Organization. Guide to
hydrological practices No. 168. 1994
EUROWATERNET. The European Environmental
Agency’s Monitoring and Information. Network for
Inland Water Resources. Technical Guidelines for
Implementation. Technical Report No. 7.
Copenhagen, 1998.
Grigory Chekan, Alexander Stankevich, Vladimir
Korneev. System of monitoring and assessment of
the transboundary river basins in Belarus.
International <strong>Conference</strong> on Hydrological
Challenges in Transboundary Water Resources
Management. Koblenz, Germany 25-27 September
2001