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Albania
Drainage
Nearly all of the precipitation that falls on Albania drains
into the rivers and reaches the coast without even leaving the
country. In the north, only one small stream escapes Albania.
In the south, an even smaller rivulet drains into Greece. Because
the topographical divide is east of the Albanian border with its
neighbors, a considerable amount of water from other countries
drains through Albania. An extensive portion of the basin of the
Drini i Bardhë River, called Beli Drim by Serbs, basin is in the
Kosovo area, across Albania's northeastern border. The three eastern
lakes that Albania shares with its neighboring countries, as well
as the streams that flow into them, drain into the Drini i Zi.
The watershed divide in the south also dips nearly seventyfive
kilometers into Greece at one point. Several tributaries of the
Vjosë River rise in that area.
With the exception of the Drini i Zi, which flows northward and
drains nearly the entire eastern border region before it turns
westward to the sea, most of the rivers in northern and central
Albania flow fairly directly westward to the sea. In the process,
they cut through the ridges rather than flow around them. This
apparent geological impossibility occurs because the highlands
originally were lifted without much folding. The streams came
into existence at that time. The compression and folding of the
plateau into ridges occurred later. The folding process was rapid
enough in many instances to dam the rivers temporarily. The resulting
lakes existed until their downstream channels became wide enough
to drain them. This sequence created the many interior basins
that are typically a part of the Albanian landform. During the
lifetime of the temporary lakes, enough sediment was deposited
in them to form the basis for fertile soils. Folding was rarely
rapid enough to force the streams into radically different channels.
The precipitous fall from higher elevations and the highly irregular
seasonal flow patterns that are characteristic of nearly all streams
in the country reduce the economic value of the streams. They
erode the mountains and deposit the sediment that created the
lowlands and continues to augment them, but the rivers flood when
there is local rainfall. When the lands are parched and need irrigation,
the rivers usually are dry. Their violence when they are full
makes them difficult to control, and they are unnavigable. The
Bunë River is an exception. It is dredged between Shkodër and
the Adriatic Sea and can be negotiated by small ships. In contrast
to their history of holding fast to their courses in the mountains,
the rivers constantly change channels on the lower plains, making
waste of much of the land they create.
The Drin River is the largest and most constant stream. Fed by
melting snows from the northern and eastern mountains and by the
more evenly distributed seasonal precipitation of that area, its
flow does not have the extreme variations characteristic of nearly
all other rivers in the country. Its normal flow varies seasonally
by only about one-third. Along its length of about 282 kilometers,
it drains nearly 5,957 square kilometers within Albania. As it
also collects from the Adriatic portion of the Kosovo watershed
and the three border lakes (Lake Prespa drains to Lake Ohrid via
an underground stream), its total basin encompasses about 15,540
square kilometers.
The Seman and Vjosë are the only other rivers that are more than
160 kilometers long and have basins larger than 2,600 square kilometers.
These rivers drain the southern regions and, reflecting the seasonal
distribution of rainfall, are torrents in winter and nearly dry
in the summer, in spite of their length. This variable nature
also characterizes the many shorter streams. In the summer, most
of them carry less than a tenth of their winter averages, if they
are not altogether dry.
Although the sediment carried by the mountain torrents continues
to be deposited, new deposits delay exploitation. Stream channels
rise as silt is deposited in them and eventually become higher
than the surrounding terrain. Shifting channels frustrate development
in many areas. Old channels become barriers to proper drainage
and create swamps or marshlands. It is difficult to build roads
or railroads across the lowlands or otherwise use the land.
Irrigation has been accomplished on a small scale by Albanian
peasants for many years. Large irrigation projects were not completed,
however, until after World War II, including the Vjosë-Levan-Fier
irrigation canal, with an irrigation capacity of 15,000 hectares,
and the reservoir at Thanë reservoir, in Lushnjë District, with
an irrigation capacity of 35,100 hectares. In 1986 nearly 400,000
hectares of land, or 56 percent of the total cultivated area,
were under irrigation, compared with 29,000 hectares, or 10 percent
of the total cultivated area, in 1938.
Data as of April 1992
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