21 Updates, Conclusions, and Recommendations for “Management …
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along the whole course. Severe low-flow episodes exceeding maximum credible duration (95 of non-exceedance probability) appeared very often; such
image of distribution indicates that hydrogeological limitations, as well as
physiographical features of the catchment, are more important than macroscale
hydrometeorological conditions.
10. Low flows can be used as indicators of hydrological drought development.
In the mountain rivers, low-flow regimes are significantly affected by genetically different summer and winter low flows, while the rest of the country is
dominated by summer half-year deficits (July–September). Large transit rivers
gradually change the features of their low-flow regime along with the entrance
of successive tributaries but retain their regime specificity up to the estuary.
The high degree of hydrological drought seasonality occurs when its average
seasonal concentration date falls in the summer months. When this date is
shifted towards autumn months, the seasonality index decreases as droughts of
the winter half-year become more and more important.
11. Flood marks are very numerous in Poland. They are part of the historical heritage
and are an important source of hydrological information. The long tradition of
their installation should be continued in Poland. Flood markers should play an
important role in flood education, especially for people living in areas at risk
of flooding. Attention should be paid to the initiative to create a nationwide
database available to all Internet users and updated with their participation.
12. The spatial diversity of the flood potential indicator was stated on Polish territory. This indicator is a useful non-dimensional parameter that can be used to
compare different river basins. Together with the flood coverage map, it shows
flood exposure in various geographical regions of Poland.
13. Proper development of land exposed to flood, conforming to planning documents, constitutes the imperative goal of flood risk management, and minimization strategies in Poland. It was emphasized that full protection against
floods is impossible and that their damage and losses can only be reduced to a
severe degree and that the risk of flooding should be controlled and managed
in advance. In the European Union countries there are expected the best results
in terms of simultaneous achievement of flood risk management objectives and
Framework Water Directive environmental goals.
14. The high content of substances in the coastal waters of the southern Baltic
is mainly due to polluted rivers. The pollution volume depends on the catchment land use and the size and location of the point, linear and area pollution
sources. Strategic investments in catchment areas concerned the increase of their
retention through afforestation, counteracting water erosion in lowland areas,
restoration of riverbed and river banks, increasing retention in urban areas of
over 20,000 residents.
15. Increasing the share of renewable energy sources in Poland is an urgent
necessity. Hydropower has considerable potential in this area. Construction of
hydropower plants is not cheap and fast, but facilities of this type can function
for many years without major expenditure. However, it is necessary to draw
425
along the whole course. Severe low-flow episodes exceeding maximum credible duration (95 of non-exceedance probability) appeared very often; such
image of distribution indicates that hydrogeological limitations, as well as
physiographical features of the catchment, are more important than macroscale
hydrometeorological conditions.
10. Low flows can be used as indicators of hydrological drought development.
In the mountain rivers, low-flow regimes are significantly affected by genetically different summer and winter low flows, while the rest of the country is
dominated by summer half-year deficits (July–September). Large transit rivers
gradually change the features of their low-flow regime along with the entrance
of successive tributaries but retain their regime specificity up to the estuary.
The high degree of hydrological drought seasonality occurs when its average
seasonal concentration date falls in the summer months. When this date is
shifted towards autumn months, the seasonality index decreases as droughts of
the winter half-year become more and more important.
11. Flood marks are very numerous in Poland. They are part of the historical heritage
and are an important source of hydrological information. The long tradition of
their installation should be continued in Poland. Flood markers should play an
important role in flood education, especially for people living in areas at risk
of flooding. Attention should be paid to the initiative to create a nationwide
database available to all Internet users and updated with their participation.
12. The spatial diversity of the flood potential indicator was stated on Polish territory. This indicator is a useful non-dimensional parameter that can be used to
compare different river basins. Together with the flood coverage map, it shows
flood exposure in various geographical regions of Poland.
13. Proper development of land exposed to flood, conforming to planning documents, constitutes the imperative goal of flood risk management, and minimization strategies in Poland. It was emphasized that full protection against
floods is impossible and that their damage and losses can only be reduced to a
severe degree and that the risk of flooding should be controlled and managed
in advance. In the European Union countries there are expected the best results
in terms of simultaneous achievement of flood risk management objectives and
Framework Water Directive environmental goals.
14. The high content of substances in the coastal waters of the southern Baltic
is mainly due to polluted rivers. The pollution volume depends on the catchment land use and the size and location of the point, linear and area pollution
sources. Strategic investments in catchment areas concerned the increase of their
retention through afforestation, counteracting water erosion in lowland areas,
restoration of riverbed and river banks, increasing retention in urban areas of
over 20,000 residents.
15. Increasing the share of renewable energy sources in Poland is an urgent
necessity. Hydropower has considerable potential in this area. Construction of
hydropower plants is not cheap and fast, but facilities of this type can function
for many years without major expenditure. However, it is necessary to draw