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M. Habel et al.
40–44% and the bed load by 99% [27]. The Włocławek dam is located approx.
250 km from the estuary reach. Commissioned in 1968, it is the largest reservoir
on the Vistula basin (area of 70 km
2 , length of 55 km, storage 270 million m
3 ).
As the only one was completed in the plan of the cascade of the lower segment
of the Vistula. It had an impact on the sediment transport balance. In consequence
of the sediment transport deficit downstream the dam, and accumulation zone has
formed (and continues to form) downstream the erosion zone. At this point, the river,
being “saturated” with bed load, discharged it down its course to form, along with
the “diminishing” training reach below, a braided channel, where bed load transport
reaches up to 2.0 million tons per annum. Otherwise, the front of the erosion zone,
moving down the river at a rate of 1.1–2.2 km year
−1 [22, 40]. At present, the erosion
zone front is located at—approx. 70 km below the dam [41]. According to long-term
forecasts, this dam will visibly impact on the coastal zone around the year 2100 [17].
Many of the dredging works are the result of activities National Water Management Board “Polish Waters” (PGW Wody Polskie), which undertake a number of
intervention activities on a regional and local scale aimed at clearing river channels.
Flood safety in winter requires maintaining a proper depth on the lower Vistula for
the operation of icebreakers. Every autumn, around 300–500 thous. m
3 of sediments
from the regulation of rivers and reservoirs are extracted in the lower section of
the Vistula River. Generally, projects for the extraction of bed load sediments from
rivers and reservoirs are conducted for commercial and non-commercial purposes.
Non-commercial projects include the collection of dredges from the canals of river
basins in order to maintain the necessary operational parameters and flood safety.
Exploitation of aggregates from the Vistula River is usually of commercial nature,
which enables a reliable assessment of the amount of material extracted from reservoirs. It is estimated that the current extraction of aggregates from these reservoirs
is about 2.5 million m
3 annually.
The most frequent is the dredging of sediment material of rivers deposited in
the backwater zones of water reservoirs (e.g., at the estuary of the Dunajec River
to the Czorsztyn Reservoir), which is used for the production of various types of
construction aggregate. According to the Polish Association of Aggregate Producers,
it is estimated that in Poland in 2012–2020, about 230 million tons of aggregates
will be needed to build public (local and municipal) roads and rail routes, including
137 million tons of gravel aggregates and 240 million tons of earthen masses, rock
masses and other materials for embankments, access roads, driveways [72]. Only on
the lower Vistula commercial exploitation of sand and gravel sediments in 2005–2018
took place in at least seven locations: Toru´ n, Solec Kujawski, the area of Bydgoszcz—
Fordon, Chełmno, Grudzi˛ adz, Korzeniewo, and Kiezmark. However, this collection
collides with the areas covered by Nature 2000 program. The lower Vistula can
transport during the wet hydrological year up to 4.0 million tons of debris above
the Włocłwek Reservoir and over 1.5 million tons on the regulated section in the
cross-section Toru´ n [36]. The dredging of more sediments than the given limit value
may contribute to the disturbance of the ecosystem functioning of the river in the
estuary section.
M. Habel et al.
40–44% and the bed load by 99% [27]. The Włocławek dam is located approx.
250 km from the estuary reach. Commissioned in 1968, it is the largest reservoir
on the Vistula basin (area of 70 km
2 , length of 55 km, storage 270 million m
3 ).
As the only one was completed in the plan of the cascade of the lower segment
of the Vistula. It had an impact on the sediment transport balance. In consequence
of the sediment transport deficit downstream the dam, and accumulation zone has
formed (and continues to form) downstream the erosion zone. At this point, the river,
being “saturated” with bed load, discharged it down its course to form, along with
the “diminishing” training reach below, a braided channel, where bed load transport
reaches up to 2.0 million tons per annum. Otherwise, the front of the erosion zone,
moving down the river at a rate of 1.1–2.2 km year
−1 [22, 40]. At present, the erosion
zone front is located at—approx. 70 km below the dam [41]. According to long-term
forecasts, this dam will visibly impact on the coastal zone around the year 2100 [17].
Many of the dredging works are the result of activities National Water Management Board “Polish Waters” (PGW Wody Polskie), which undertake a number of
intervention activities on a regional and local scale aimed at clearing river channels.
Flood safety in winter requires maintaining a proper depth on the lower Vistula for
the operation of icebreakers. Every autumn, around 300–500 thous. m
3 of sediments
from the regulation of rivers and reservoirs are extracted in the lower section of
the Vistula River. Generally, projects for the extraction of bed load sediments from
rivers and reservoirs are conducted for commercial and non-commercial purposes.
Non-commercial projects include the collection of dredges from the canals of river
basins in order to maintain the necessary operational parameters and flood safety.
Exploitation of aggregates from the Vistula River is usually of commercial nature,
which enables a reliable assessment of the amount of material extracted from reservoirs. It is estimated that the current extraction of aggregates from these reservoirs
is about 2.5 million m
3 annually.
The most frequent is the dredging of sediment material of rivers deposited in
the backwater zones of water reservoirs (e.g., at the estuary of the Dunajec River
to the Czorsztyn Reservoir), which is used for the production of various types of
construction aggregate. According to the Polish Association of Aggregate Producers,
it is estimated that in Poland in 2012–2020, about 230 million tons of aggregates
will be needed to build public (local and municipal) roads and rail routes, including
137 million tons of gravel aggregates and 240 million tons of earthen masses, rock
masses and other materials for embankments, access roads, driveways [72]. Only on
the lower Vistula commercial exploitation of sand and gravel sediments in 2005–2018
took place in at least seven locations: Toru´ n, Solec Kujawski, the area of Bydgoszcz—
Fordon, Chełmno, Grudzi˛ adz, Korzeniewo, and Kiezmark. However, this collection
collides with the areas covered by Nature 2000 program. The lower Vistula can
transport during the wet hydrological year up to 4.0 million tons of debris above
the Włocłwek Reservoir and over 1.5 million tons on the regulated section in the
cross-section Toru´ n [36]. The dredging of more sediments than the given limit value
may contribute to the disturbance of the ecosystem functioning of the river in the
estuary section.