Model dfpsir nishava_en

IPA CBC Programme Bulgaria - Serbia

EUROPEAN UNION Bulgaria – Serbia IPA Cross-border Programme

“Assessment of flood risk – a base for sustainable development in upper part of Nishava catchment”

1

IMPLEMENTATION OF THE MODEL „DRIVING FORCES – PRESSURE –

STATE – IMPACT - RESPONSE” IN FLOOD RISK ASSESSMENT IN THE

UPPER NISHAVA CATCHMENT

I. METHODOLOGICAL APPROACH

The development of a model "Driving Forces - Pressures - State - Impact -

Response" proposed by the European Environment Agency /EEA/ is the first step

in flood risk assessmenty. (Fig. 1).

Figure. 1. Conceptual framework for assessing flood risk

RESPONSES

DRIVING FORCES

IMPACT

PRESSURE

STATE

Climate

Landscape factors

of the basin

Landuse changes

Urbanization

Transport infrastructure

Soil sealing

Damages

Social-economic

consequences

Environmental

consequences

Prevention, protection and

mitigation measures for

negative consequences

Historical and future floods

Types of floods

Maximum run-off




2

In the preliminary risk assessment, one of the simplest methods for estimating the

flood hazard is the introduction of the "criterion of horizontal distance". A horizontal

distance between the object /settlement, industrial objects, cultural sites, railway

and road network, protected natural areas, etc./ can be determined and located

near the river Nisava (Fig. 2).

Figure 2. Schematic sketch of the criterion of horizontal distance

Our preliminary research showed that the distance of objects at 200 m from the

river is suitable for the conditions of the river basin Nišava.

According to the directive 60/2007-EU, the following categories are used in

assessment of adverse effects: "human health", "industry", "environment" and

"cultural heritage".

II. IMPLEMENTATION OF THE MODEL „DRIVING FORCES – PRESSURE –

STATE – IMPACT - RESPONCE”

DRIVING FORCES

река 1

река 2

населено

място 1 населено

място 2

населено

място 3

X m

X m X m

X m

заплаха от

наводнения

риск от

наводнения




3

According to the conceptual framework of the model /Fig.1/ drivers for flood

formation are the climate and landscape conditions of the research basin.

Climatic factors

1.Atmosferic-circulation systems

The geographical location of the territory of Serbia defines the invasion of air

masses coming predominantly from the northwest (Ducic, Radovanovic, 2005).

The types of air masses that determine the weather conditions in the basin of

Nishava River are Arctic - sea, continental arctic, continental polar, polar - marine,

tropical - continental, tropical sea.

Fig. 3 Hydrometrical network within Nishava River Basin

2. Air temperature

The analysis of data from 55 weather stations for the period 1946-2006 shows

that the highest average monthly temperatures are in July and lowest in January.

In the northern part of Serbia, the average annual temperatures are between 10.8

and 11.5 ° C, and in the lowlands of Central and Southern Serbia temperatures

are between 10.0 and 12.1 ° C.




4

Precipitation factors

The average precipitation in the territory of Serbia is 699.7 mm / year. The mode

of precipitation is very diverse, since the annual rainfall in different parts of the

country reaches extreme values (1500 mm drainage area of White River Drim to

900 mm in the upper parts of the river Ibar river or river Plavska Lepenitsa).

Generally, the month of greatest rainfall is June, and the month of least - February

or March.

Landscape factors

1. Lithological basis

Nishava River Basin at Pirot, without Visocica, is composed of limestone,

represented by marly-sandstone passing into massive limestone, urgonian

limestone with impurities of shales, marls and sands.

Fig. 4 Geological structure of Nishava River Basin

2. Landscape




5

Serbia is a country with mostly hilly and mountainous terrain type (65% of the

territory) and 60,000 km2 of agricultural land are permanent. About 30% of the

Danube Basin in Serbia is forested (ICPDR, 2006). The relief within the river

catchment is mostly mountainous.

3. Soils

Three main types of soils are typical of the region - organic-rich black soil

(chernozem), slightly acidic brown podzolic, podzolic soils infertile.

Fig. 5 Soils in Nishava River Basin

4. Vegetation

The biodiversity in Nišava River Basin is characterized by big diversity. Each

altitude zone is characterized by a certain type of vegetation. In eastern Serbia,

the vegetation is represented by three main types: meadows, pastures, forests.

PRESSURE

The main factors which generally intensify torrential processes are changes in land

use, soil sealing, urbanization and transport infrastructure.




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1. Changes in land use

Figure. 6 Land use in Nishava River Basin / Corine, 2006 /

These destructive changes in the land cover and landscape often weaken the

retention and bioecological functions of forests and strengthen-torrential erosion.

1. Soil sealing

Soil sealing in recent years is estimated to be substantial global threat not only to

soils but also to intensification of the surface run-off formation during heavy rains.

Compared with 2000, in 2006 the growth of soil sealing rate is insignificant - with

10.69 km2. Almost negligible in 2006 is the increased the area of industrial and

commercial buildings and road infrastructure and the area of sports, and

recreation and urban fabric slightly decreased.

2. Urbanization

Generally, urbanization increases the frequency of flood occurrence and reduces

the time for formation of high waves due to soil sealing. Flooded river terraces of

Nišava river and its tributaries are a preferred place for business development.




7

The settlement network is comprised of 307 cities /incl. 7 cities/. The density of

urban settlement network is 7.5 / 100 km2. 72% of the total area of settlements lay

within the 200m buffer zone around rivers.

Fig. 7 Settlement network inNishava River Basin

1. Transportation infrastructure

The transport infrastructure intensifies the processes of floods formation and thier

catastrophic effect. The еxisting road network in Nishava river basin has

inadequate drainage systems, which redirects surface runoff from other areas

during intense rainfall, which together with the local surface runoff can cause a

rapid rise in river level and a flood event. It should also be taken into account that

the transport infrastructure is crucial for the evacuation of the population and

access to emergency service in case of flooding.




8

Fig. 8 Transport infrastructure in the buffer zone of 200 m in Nishava River Basin

VI.STATE

The described climatic and landscape features of the catchment of Nisava river

and the changes occurred in the recent years in termds of land use, intensification

of urbanization processes and infrastructure development are key factors for

formation and occurrence of floods in the river basin. Particularly devastating

torrential floods causing considerable damage and casualties are those in 1929,

1942-1943, 1957-1958, 1980, 30.11.2007, 15.05.2010




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Fig. 9 Floods in Nishava River Basin

VII. IMPACT

VII.1. Negative effects of past floods

No information about past floods in Nishava River Basin was found in the sources

of information. However, it can be concluded that they are important primarily in

relation to protected categories "human health" and "business".

VII.2. Potential negative consequences

The potential risk in the Nishava River Basin exists regarding the protected

categories "human health", "business", "environment" and "cultural heritage".

Table 1. Affected people

Settlements

within a 200 m

Size of

urban

Area of the

city,

Population,

number of

Occupancy

density of

Number

of people




10

buffer zone

from rivers

area,

km2

located in

200 m

buffer zone

of rivers,

km2

people population,

prs/ km2

affected

Godech 6,14 3,72 4425 720 2677

Bela palanka

2,17

0,69 8112

3731 2575

Trun

Dimitrovgrad 1,91 0,93 6247 3270 3052

Pirot 7,96 1,87 38432 4828 9039

Nis 22,32 1,87 177972 7974 32417

Table 2. Potential risk category „Industry”

Pro

tec

t

ed

are

a

Criterion Total In buffer

200m

% E

co

no

mic

ac

tivity

Industry

Industrial and

commercial objects,

km2

8,45 1,09 12,9

Transport infrastricture

Lenght of the

transport

infrastructure, km

946,176 271,426 28,7

Total lenght of the

railway network, km

175,847 61,48 35,0

Agriculture

Complexes of 436,57 55,86 13,0




11

fragmented

agricultural land, km2

Vineyards, km2 1,53 0,31 20,3

Non-irrigated arable

land, km2 268,47 39,90 14,9

Agricultural land with

significant areas of

natural vegetation,

km2 506,72 102,82 20,3

Pasture, km2 109,83 10,47 9,5

Fruit and berries

plantations 0,73 0,11 15,1

"E

nv

iron

me

nt"

Protected areas Natura 2000

Birds Directive 467,28 58,10 12,4

Habitats Directive 453,05 70,73 15,6

Protected areas /R.

Serbia/ 823,94 74,69 9,1

Table 3. Potential flood risk for the transport infrastructure in Nishava River Basin

Class roads Length of road network,

km

Length of

road

network,

located in

the buffer

zone 200,

km

% Of the

length of the

road network

located in

bufernnata

200 m area.

Highway 6,843 1,369 20

Highway project 10,057 2,645 26,3

Second class roads 304,300 86,092 28,3




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First class roads 170,232 40,379 23,7

Third class roads 454,742 140,939 31,0

Table 4. Flood risk and NATURA 2000 objects

Name Area km2 Area km2 in 200

m buffer zone

% of area in 200

m buffer zone

Birds directive 2009/147/ЕС

Noevci 3,69 0,82 22,2

Ruy 173,45 18,38 10,59

Rayanovci 90,24 10,70 11,85

Ponor 128,19 16,71 13,03

West Balkan 71,69 11,47 15,99

Habitats directive 92/43/ЕЕС

Rebro 2,13 0,91 42,72

Dragoman 109,15 13,61 12,46

West Balkan

Mountain and

Forebalkan

274,21 48,60

17,72

Kurvav kamuk 37,80 2,12 5,6

Ruy 17,06 5,25 30,77

Lubash 12,67 0,20 1,57

Protected reas /R.Serbia/

Erma river gorge 0,15 0,11 73,3

Temna dupka 0,19 0,03 15,78

Kotlite 0,17 0,15 88,23

Zaskogo 0,27 0,11 40,74

Uruchnik 0,16 0,08 50,00

Klisura Osanicke

reke 80,84 7,36

9,1




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Bifurkacija reke

Nerodimke 74,21 66,81

90,02

VIII. ANSWER

The measures taken in Nishava River Basin in the past are engineering-technical

/corrections of the watercourses, construction of dams and protective walls/. The

river flow is regulates within the cities Godech and Dimitrovgrad.

The analysis of the functioning system of measures for flood protection shows that

it is not particularly efficient in cases of extreme floods with very little repetition.

Acceptable level of protection could be achieved only after detailed mapping of the

flood risks under various scenarios. An adequate scheme of measures (hydro-

technical) and non-engineetring measures needs to be determined.

This publication was elaboraed with the assistance of the European Union, through IPA Cross-border co-operation programme

CCI No 2007CB16IPO006. The contents of this publication is a responsibility of the SRD-SU „St. Kliment

Ohridski” and should in no way be accepted as a statement of the European Union or the Managaing Authority of the programme.

Model dfpsir nishava_en

Technology

river ibar river

nishava river basin4

territory of serbia

river basin niava

niava river basin

eastern serbia

river nisava

basin ofnishava river