Prof' Agim Selenica Institute of Hydrometeorology of Albania

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Prof. Agim Selenica Institute of
Hydrometeorology of Albania

• Flood Potential in Albania

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1. Introduction
? Floods are a natural phenomenon in Albania
? Paradoxically, flood is both feared
(destructive) and valued. (for the ecosystem of
Western Plain of Albania, flood is vital in many
respects
? The disadvantages of structural approach and
advantages of non-structural approach
? The only long-term solution consists of keeping
flood-vulnerable development and uses out of the
floodplain
? Maping of flood potential an important non
structural measures, which serves also as an inex
of the risk of inundation of a given territory
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2. Flood potential based on historical records
? The hydrographic basin of the rivers of Albania
43,305 km2 from which 28,748 km2 situated
within the state territory of Albania. The rest,
which belongs to the catchments of the rivers
Drini and Vjosa, is situated in Greece, FYR of
Macedonia and Serbia and Montenegro. Annual
discharge of this basin 1308 m3/s, or 30l/s.km2 ,
one of the highest in Europe (fig. 1)

? The climate of Albania, in general, is
Mediterranean. with some degree of
continentality. Average annual rainfall 1485 mm,
the highest 24 h precipitation oscilate from 100
to 420 mm (fig.2)
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Fig.2
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? The floods, in general, have a pluvial origin
and so they are observed during the period of
November-March, when it flows 80-85 of the
annual runoff. They are flashy and in the main
rivers they traverses the hydrographic network in
8-10 hours
? Based on the information of historical records
peak discharges and the volumes of the floods are
computed for different return periods. The best
fiting is for Pearson III distribution (table 1)
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Table 1 Peak discharges and volumes of the
floods with different return periods

• No River Station Peak discharges
  Volumes of the floods
• (m3/s)
  (millions m3)
• Return period
  (years) Return period (years)
• 
  50 100 50
  100
• Mati Milot 2700 3400
  267.393 308.445
• Ishmi - Sukth Vendas 1230 1380
  77.220 83.655
• Erzeni - Ndroq 1250 1400
  80.437 90.090
• Shkumbini - Rogozhine 1900 2200
  192.146 222.485
• Semani Ura e Kucit 2600 3000
  348.488 402.101
• Vjosa - Mifol 4350 5000
  768.353 883.164

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? The specific discharge of the peak - an
indicator of the flood potential, which could
serve also as a certain risk of inundation
? A study was carried out in country scale, in
order to estimate the parameters of floods I 54
hydrological stations
? Using these parameters and the floods factors,
a multiple regional correlation between them is
estimated. The regression equation for the rivers
with rain floods Qm 0.017
A 0.68 R1.2 H 0.032 I 0.69
where Qm - mean maximum discharge of the peak
in m³/s.km2 A - surface of the
catchment area in km , R- maximum 24 h rainfall
in mm H - mean altitude of the catchment
area in m, I - mean slope of the catchment
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? Using these relations, the specific discharge
of the peak (module) is calculated for 50 other
rivers of the country, with the surface from 100
to 400 km2
? With these values of the peak specific
discharges a map of the flood potential for the
country is designed (fig.3) As an index of the
flood potential the standard specific discharge
of the peak (module) is chosen, which corresponds
to a return period of 100 years and a surface of
the catchment area of 100 km2
? The standard module is calculated by the
formula 3, established for the Albanian
territory
q(100, 1 ) q(A, 1 )
(A/100)-0.355 where q(100, 1 ) is the
module for a standard catchment surface of 100
km2 and an exceeding probability of 1 and q(A,
1 ) the module of a certain catchment area with
a surface of A and the exceeding probability of
1. (Fig.4)
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Fig. 3
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3. Main conclusions
? The highest 24 h precipitation oscilate from
100 to 420 mm the highest 24 h precipitation
oscilate from 100 to 420 mm
? The best fiting was found for Pearson III
distribution
? The map of flood potential shows that the
values of the maximum module varie too much in
Albania (from 2 to 10 m³/s.km2)
? The highest risk of inundation is for Western
Plain of Albania
(fig. 5)
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