Water Management Balances (WMB) Assessment of a River Basin Water Resources System in

Stiliana YANCHEVA, Anna YORDANOVA, Maria TEMELKOVA

Institute of Water Problems at Bulgarian Academy of Sciences Sofia, BULGARIA Email: [email protected]

A b s t r a c t

The paper present the received results from water management balance (WMB) for existing multi - purpose water resources system (WRS) in the Archar and Vidbol river basins – two important feeders of Danube river in North-West Bulgaria. It is done a short description and are marked the specific features of present water resources use in the river valley. For certain points from the river network are determined the main statistical characteristics of natural river flow (for the period 1961 - 2004 year). Based on the developed scheme for water use and different variants of the individual users needs are made water management balances (WMB). Experimental simulations researches for WMB are carried out with prepared input information for the inflow and water demand. Sequences for the inflow and irrigation demand in the relevant points are 44 years long by months. The results for different variants of WMB are analyzed and it is made assessment of water availability of different users. The Archar and Vidbol river basins problems in result of the economical, political and climate changes are discussed.

Key words: river basin, water management balance, water supply availability, water resources management, operation, management, computer model, simulation

General principles in WMB

1. Water management balance (WMB) is the correlation between a flow and water consumption for: • fixed territorial unit from earth surface; • fixed time interval; • recognizing water human activity

2. Two parts of WMB – flow and water demand, giving his income and outcome part are forming and changing in time and space under influence of water human activity that includes:

• hydro technical construction of river streams with regulation of inflow; • water utilization, according to the specifics of different branches of the water economy – industry, irrigate, water supply, hydro power etc.; • all activities changing the environment, connected with water.

3. Comparison the income to the outcome:

• is solution in which are reflecting the main sides of the using and distribution process of water resources in the water economy, • It is not simple arithmetic operation, simple accounting balance, simple water balance.

4. Comparison the flow to water demand is going on :

• the space ( in territory and in height) • quantity and quality (correspondence with the requirements of the consumers) • the time i.e. for given level of economy development • the given time interval.

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 1/13 General activities in WMB

First: Fixing the territorial unit for which the WMB is developing (water management system, river basin, parts from it, the whole country);

Second: Assigning the economical level for which is developing WMB (at present or in the perspective, in conformity with the stage of water management investigations – operating, designing, planning);

Third: Choosing the time interval for developing WMB (year, month or another wanted time interval);

Forth: Composition of water management scheme for using the water resources which is the main requirement for converting the water balance for given territorial unit in WMB. There is no WMB without accepted scheme for water use.

Following the succession

FIRST: In this case are developed WMB for ARCHAR and VIDBOL river basins;

SECOND: WMB are developing for different variants of inflow and water demand, for two stages: at present and in perspective till 2015-2020;

THIRD: It is accepted the comparison inflow to water demand to be in months

FORTH: Because the two river basins are hydraulically connected, they are considered as one water management unit, for which is elaborated scheme for water resources use.

General database of Archar and Vidbol river basins

1. Description of the real scheme for water use

Archar and Vidbol rivers are feeders of Danube river. They are situated in the North-west part of Bulgaria. Water management of the two rivers is connected and in developing the WMB the two river basins are considering united in one joint scheme. Main water consumer is the ”Rabisha” Irrigation System, which is fed from the lake Rabisha reconstructed as a reservoir (”Rabisha” reservoir – total volume 42 mln.m3). The reservoir is feeding by artificial way, and for catching and leading the water to it are constructed three derivations. Derivation ”Vidbolska”, catching and leading the water of Vidbol river and four of its feeders with the help of 5 constructed headworks (each with equipped for a discharge of Q = 1.8 m3/sec.). Derivation”Archar” (equipped for a discharge of Q = 2.7 m3/sec), is starting from the ”Raianovtzi” reservoir. The reservoir is situated on the Archar river next to the Raianovtzi village and its total volume is 0.406 mln.m3. Third derivation (equipped for a discharge of Q = 0.45 m3/sec), is including from the Derivation”Archar” next to the entrance shaft of the culvert siphon on Archar river. It is starting from the ”Oshane” reservoir. The “Oshane” reservoir is situated next to the Oshane village on the Oshane dere river and its total volume is 0.609 mln.m3. The joint part of the derivation “Vidbol” and “Archar” has a discharge of Q = 4.5 m3/sec. The intake from the reservoir is carried out through a water tower at the outlet of the reservoir, which is reconstructed as long free flow tunnel (equipped for a discharge of Q =5 m3/sec.). In the begging of the tunnel is the Pumping Station “Tolovitza” (equipped for a discharge of Q = 1.87 m3/sec.). After the tunnel starts the canal M2, The pressure pipeline of the Pump Station next to the its outlet shaft continues in the main canal M1. From the canal M1,passing along the Rabisha ridge, next to the Pump station “Rabisha” begin the canal P-1. Canal M1 reach to the Pump Station “23 September” (equipped for a discharge of Q = 450 l/sec.), From the outlet shaft of the Pump Station “23 September” starts canal P-10. Canal M2 goes to the North, crosses Vidbol river with seg-pipe (equipped for a discharge of Q = 3.2 m3/sec.). The canal from the outlet shaft of the seg-pipe goes to the left and reaches the Pump Station “Shishmanovo” (equipped for a discharge of Q = 0.95 m3/sec.). To the right of the

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 2/13 outlet shaft of the seg-pipe starts canal P-12. The biggest facility on this canal is the seg-pipe ”Virovete”. From the entrance shaft of the culvert siphon goes canal 3-CD-1. The size of the attached areas (constructed and with fitted infrastructure), irrigated from these canals is given in Table № 4. Along the Archar river and its feeders are constructed many catchments from surface and underground water in the regions of the village of Salash, the village of Oshane, the village of Rabisha, the village of Raianovtzi, the village of Darjantzi, the village of Bela, the village of , which provides the villages with drinking water and water needed for industry. On the Salashka river (right feeder of the Archar river), in its upper upstream, on its feeder Gradska river next to the village of Dubravka is constructed water reservoir “Dubravka” (total volume 0.730 mln.m3) , which water is used for irrigation of the areas in Irrigation field Dubravka”. In the Vidbol river basin is interesting for the water management its left feeder-Gramadska river. The two biggest constructed water reservoirs on it are”Farfun” reservoir (total volume 0.500 mln.m3) , used for fish-farming and “Bojuritza” reservoir (total volume 1.43 mln.m3) used for irrigation of the areas of Irrigation field ”Bojuritza” and fish-farming. Catchment next to the village of Sinagovtzi takes water from Vidbol river and through Main Irrigation Canal irrigates Irrigation field “Sinagovtzi”. In the Vidbol river basin and its feeders, next to the villages Boianovo, Rakovitza, Sinagovtzi, Jeglitza, Milchina luka etc. there are constructed outlets from surface and underground water for providing with water the villages in the river basin.

2. Description of the calculate scheme for water use

Basing on the real scheme for water use is developed calculate scheme, which is the base of developed WMB for the two river basins (Fig.1) and including:

• From the water management point of view for Archar river and Vidbol river are important: Archar river Salashka river Oshan dere river Vidbol river Gramadska river Svadbiste river etc.

• In 10 points on the river network is restored the natural regime of the river flow (rows in months from 1961 to 2004), (on Fig. 1 is circle with number from 1 to 10 in it) (Table №1)

Table №1. Statistical parameters of the river flow rows

№ № Name Q medn Cv Cs no annual de (m3/sec) 34 1 Archar river (mouth) 1,813 0,392 -0,201 29 2 Salashka river (feeder of Archar river-mouth) 0,786 0,392 -0,201 23 3 Salashka river ( feeder of Archar river-Vestitza village) 0,571 0,392 -0,200 8 4 Oshane river (damn wall of Oshane water reservoir) 0,104 0,392 -0,200 9 5 Raianovtzi reservoir (damn wall) 0,338 0,391 -0,197 1 6 Archar river (catchment Rianovtzi) 0,247 0,391 -0,199 16 7 Vidbol river (Vidbol catchment, next to Rakovitza village) 1,134 0,405 0,572 4 8 Gramadska river ( left feeder of Vidbol river) 0,261 0,405 0,567 13 9 Vidbol river (mouth) 1,095 0,405 0,567 7 10 Oshane river (damn tail of Oshane water reservoir) 0,094 0,392 -0,196

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 3/13 IF"Bojuritza"

IF"Sinagovtzi" municipality

Dunavtzi Farfun water Bojuritza water water N canal catcment 1 reservoir Mi l chi na l uka reservoir MIC 5 Gramadska river 6 Sinagovtzi Boianovo Gramada IF"Gramada"Ì -2 IF"Gramada"Ð-12 r municipality e Jeglitza iv Ivanovtzi Gramada r a r a b

a 2 2 v Sracimirovo -1 o

Ð s

r

l a

l a J e

a n v n i

a r a IF"Vulchek" c l

c o b Danube river id IF"Pump station 23 " Pump station"Shishmanovo" canal 3-ÑÄ-1 V municipality Makresh water catchment IF"Makresh" Rakovitza Makresh Vulchek Car Shishmanovo 7 Jonovetz river Vidbol river Vidbol river r ve ri a z l it a Podgore db n a a v c water catchment S IS"Rabisha"

Tolovitza Pump IF"Rabisha" station"Tolovitza" water catchment Pump station"23 IX" al can water catchment 1 Rabisha water IF"Dimovo" Ì -1 reservoir canal canal Vidbol water catchment Pump station"Rabisha"

r ha rc A al an municipality Dimovo Municipality Makresh c

Raianovtzi Dimovo Rabisha Kladorub Ostrokaptzi Vurtop Durj anitza

5 4 Archar river Archar river 2 Archar river Archar river Raianovtzi municipality Dimovo Lagoshevtzi Archar water reservoir municipality Makresh municipality municipality municipality Dimovo Belogradchik Bela Oshane water er reservoir riv r) 3 ka rive Oshane sh ka ala titz S es 4 (V

Vestitza Danube river HMS1 municipality ere Belogradchik e d an Osh r IF"Dubravka" ive h r las Sa

Salash 2 municipality Dubravka water Belogradchik Dubravka Sheme of water management use of reservoirr

e

v i

r

a Archar and Vidbol river basins

sk

d

a

r

G

Figure 1 Sheme of management of ARCHAR and VIDBOL River Basins

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 4/13 • Six water reservoirs are included (volume over 0.5 mln.m3), (on Fig.1 blue triangle with № from 1 to 6 in it), (Table № 2.)

Table № 2. Database for the included reservoirs in the calculate scheme № Name № Name of the Name of the Village Municipality Volume Property Poured Height of Function node reservoir river (mln.m3) area on the wall (dka) (m) 2 IaRabisha 1 Rabisha Lake Rabisha Rabisha Belogradchik 42.000 State 3246 Irrigation 7 IaDabrav 2 Dubravka Dere Dubravka Belogradchik 0.730 Municipality 134 20 Irrigation 8 IaOshane 3 Oshane Oshane dere Oshane Belogradchik 0.609 State 84 22.5 Irrigation and fish farming 9 IaRaianov 4 Raianovtzi Archar river Raianovtzi Belogradchik 0.406 Municipality 40 16.4 Irrigation and fish farming 3 IaFarafun 5 Farfun Gramadska river Gramada Gramada 0.500 Municipality 171 9.8 Fish farming 4 la Bojurica 6 Bojuritza Sinagovsko dere Sinagovtzi Gramada 1.430 State 237 17 Irrigation and fish farming

• The irrigated areas are separated in 4 Irrigation fields (on Fig. 1 green rectangle), (Table № 3.)

Table № 3. Database for the included irrigation fields (IrrF) in the calculate scheme № node Name № Name Irrigated areas Constructed irrigated areas (dka) (dka) 14 NS Rabis 1 ” Rabisha” reservoir ”Rabisha” irrigation system IrrF ”Rabisha” 220 720 IrrF „Dimovo M-1” 4 235 11 070 IrrF „Pump station 23 ІХ” 2 700 4 910 IrrF „Vulchek” 3 000 3 124 IrrF „Makresh” 6 798 10 000 IrrF „Gramada Р-12” 12 061 15 279 IrrF „Gramada М-2” 3 802 6 119 Total: 32 816 51 222 4 NS Bojur 2 ”Bojuritza”reservoir-IrrF ”Bojuritza” 3 560 6 985 27 NS Dabra 3 ”Dubravka”reservoir-IrrF”Dubravka” 1 000 1 000 21 NS Sinag 4 Main Irr.Canal Sinagovtzi-IrrF”Sinagovtzi” 600 600

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 5/13 In developing WMB in the Archar and Vidbol river basins and their feeders the water users are separated as followed: WATER USERS WITH WATER LICENCE (Table № 4.) and WATER USERS WITHOUT WATER LICENCE with different purpose (Domestic water supply - DWS, Industrial water supply,, Irrigation supply). The reason is that the Water resources use register for Archar and Vidbol rivers doesn’t include all the users from DWS and Irrigation supply.

• WATER USERS WITH WATER LICENCE

1. SURFACE WATER (no issued water licence) 2. UNDERGRAUND WATER (arranged in groups and localized in 4 outlets) for: Domestic water supply - 3 item (on Fig. 1. purple circle, number next to it and red ellipse). Industrial water supply - 1 item (on Fig. 1. purple circle, number next to it and orange rhomb).

Table № 4 Underground water use (with issued water licence ) in Archar river basin № Name № №g Owner Water Place of water catchment Place of water use Function Annual max Usable no wat rou licence of water limit Q l/s groun de er p № use m3 dwater per l/s mit Town/vil Municipali Distr Town/ Municipality District lage ty ict village

10 p1gWS 1 1 "V i К" 100930 Rabisha Belogradch Vidin Rabisha Belogradchik Vidin DWS 220752 7 There ЕООD ik Tolovica is not Raianovci 11 p2gI 2 1 "Eco." 101350 Dimovo Dimovo Vidin Dimovo Dimovo Vidin Industry 137376 9 10.7 ООD Underground water use (with issued water licence ) in Vidbol river basin 5 p3gWS 3 1 "Viprom" 100872 Milchina Gramada Vidin Milchina Gramada Vidin DWS 63072 5 16.68 АD luka luka 6 p4gWS 4 1 "Hana 100881 Dunavci Vidin Vidin Dunavci Vidin Vidin DWS 34375.7 4.5 6.9 progres" АD 2 "V i К" 100980 Dunavci Vidin Vidin Jeglica Vidin Vidin DWS 126162 4 6.776 ЕООD Sum: 160537.7

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 6/13

• WATER USERS WITHOUT WATER LICENCE (arranged in groups and localized in 13 outlets) for:

1. Domestic water supply - DWS - 9 item (on Fig. 1. red circle, cipher next to it and red ellipse with the cipher inside corresponding to the municipality in which are situated the group of villages and towns attached to one outlet).

2. Irrigation - 9 item (on Fig. 1. green rectangle and the name of Irrigation Field).

• ” Rabisha” reservoir - ”Rabisha” Irrigation System (with 7 Irrigation Fields ):

1. IF ”Rabisha”

2. IF „Dimovo M-1”

3. IF „Pump station 23 ІХ”

4. IF „Vulchek”

5. IF „Makresh”

6. IF „Gramada Р-12”

7. IF „Gramada М-2”

• ”Bojuritza” reservoir IF ”Bojuritza”

• “Dubravka” reservoir IF”Dubravka”

• Main Irr.Canal Sinagovtzi IF”Sinagovtzi”

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 7/13

Domestic water supply ( DWS) in of ARCHAR and VIDBOL river basins and their feeders

Table № 5. Domestic water supply ( DWS) in ARCHAR RIVER BASIN

№ Name № no ou Place of the outlet I VARIANT ІІ VARIANT III VARIANT de tle t. River Village Municipality Habita m3/h/ Demand Habit m3/h/ Demand Habit m3/h/d Demand nts day m 3 ants day m 3 ants ay m 3 25 1WS 1 Salashka Salash 1. BELOGRADCHIK Includes 4 villages 1888 0,181 124730,7 1756 0,240 153825,6 1756 0,188 120496,72 23 2WS 2 Archar Oshane 1. BELOGRADCHIK Includes 1 villages 1663 0,181 109866,0 1547 0,240 135517,2 1547 0,188 106155,14 28 3WS 3 Archar Rabish 1. BELOGRADCHIK a Includes 1 villages 321 0,181 21206,865 299 0,240 26192,40 299 0,188 20517,38 2. DIMOVO Includes. 1 villages 41 0,169 2529,085 44 0,240 3854,40 44 0,188 3019,28 Sum: 23735,9 1756 30046,80 23536,66 22 4WS 4 Archar Raiano 1. BELOGRADCHIK vtzi Includes 1 villages 147 0,181 9711,55 137 0,240 12001,20 137 0,188 9400,94 2. MAKRESH Includes 1 villages 50 0,152 2774 58 0,240 5080,80 58 0,188 3979,96 Sum: 12485,555 17082 13380,9 12 5WS 5 Archar Durjanit 1.DIMOVO 146 0,169 9006,01 156 0,240 13665,60 156 0,188 10704,72 za 103 0,169 6353,555 110 0,240 9636,00 110 0,188 7548,20

2882 0,169 177776,17 3083 0,240 270070,80 3083 0,188 211555,46 Includes 3 villages Sum: 3131 0,169 193135,73 3349 0,240 293372,40 3349 0,188 229808,38 31 6WS 6 Archar Bela 1. DIMOVO Includes 11villages 2329 0,169 143664,36 2492 0,240 218299,20 2492 0,188 171001,04 2. MAKRESH Includes 2 villages 599 0,152 33232,52 689 0,240 60356,40 689 0,188 47279,18 Sum: 176896,88 278655,6 3349 218280,22

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 8/13

Table № 6. Domestic water supply ( DWS) in VIDBOL RIVER BASIN

№ Name № no ou Place of the outlet I VARIANT ІІ VARIANT III VARIANT de tle t. River Village Municipality Habita m3/h/ Demand Habit m3/h/ Demand Habit m3/h/d Demand nts day m 3 ants day m 3 ants ay m 3 20 7WS 7 Vidbol Sinago 1.VIDIN 96 0,181 6342,24 82 0,288 8619,84 82 0,225 6734,25 Includes 2 villages vtzi 381 0,181 25170,765 324 0,288 34058,88 324 0,225 26608,5

Sum: 477 0,181 31513,0 406 0,288 42678,7 406 0,225 33342,7 17 8WS 8 Gramads Boiano 1.GRAMADA ka vo 46 0,201 3374,79 53 0,240 4642,80 53 0,188 3636,86 212 0,201 15553,3 244 0,240 21374,4 244 0,188 16743,2 11 0,201 807,015 13 0,240 1138,80 13 0,188 892,06 57 0,201 4181,805 66 0,240 5781,60 66 0,188 4528,92

Includes 5 villages 1885 0,201 138293 2168 0,240 189916,8 2168 0,188 148768,1 Sum: 2211 0,201 162210,0 2544 0,240 222854,4 2544 0,188 174569,2 16 9 Vidbol Rakovit 1.MAKRESH 306 0,152 16976,88 352 0,240 30835,20 352 0,188 24154,2 za 671 0,152 37227,08 772 0,240 67627,20 772 0,188 52974,6

Includes 3 illages 158 0,152 8765,84 182 0,240 15943,20 182 0,188 12488,8

Sum: 1135 0,152 62969,8 1306 0,240 114405,6 1306 0,188 89617,7

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 9/13 Results from water management balances (WMB)

For water resources assessment in Archar and Vidbol river basins are developed WMB in different variants for water demand and river flow. In this case are disposed only the results from: • Variant I, in which the water demand for Domestic water supply ( DWS), Industrial water supply is given from database of issued water licences from the Danube River Basin District, Irrigation water supply is fixes for all irrigated areas, and restored natural regime of the river flow in every of the 10 points in the region is given in months for the whole 44 years period with two sub-variants : Sub-variant I.1 is calculated for hydrology forecast given with the whole row 1961-2004, and Sub- variant I.2 – for 10 years dry period (extract 1985 – 1994). • VARIANT III with Sub-variant III.1, in which the water demand for Domestic water supply is given with the water use norms, and the total water losses in the system are 60 %. It is accepted the water for ecological preserving of river system to respond to the temporary instruction of the Ministry of Environment and Water of Bulgaria. The WMB results in Sub-variant I.1, Sub-variant I.2 and Sub-variant III.1, obtained from the experiments with the help of the software SYMIL (network simulation-optimization computer program) are given in Tables № 7, № 8 and № 9

Table №7 WMB OF ARCHAR AND VITBOL RIVER BASINS - VARIANT I.1

WATER DEMAND : IRRIGATION WATER SUPPLY, DOMESTIC WATER SUPPLY ( from Water Licences and Data of National Statistical Institute for 2004), INDUSTRIAL WATER SUPPLY (from Water Licences ) PERIOD ( 1961 – 2004) D A T A EXCEEDENCE PROBABILITY % W , Average Average start , average shortage Node annual In In In Index Water user № demands З З volumes years months З [100m ] [100m ] [100m ] 4 NSBojuri 11483 13388 0 100 100 100 0 5 p3gWS 631 0 0 100 100 100 0 6 p6gWS 1606 0 0 100 100 100 0 10 p1gWS 2207 0 0 100 100 100 0 11 p2gl 1375 0 0 100 100 100 0 12 5WS 1932 0 0 100 100 100 0 14 NSRabish 84227 0 3056 96,37 93,18 95,83 1.395 16 9WS 631 0 0 100 100 100 0 17 8WS 1621 0 0 100 100 100 0 20 7WS 317 0 0 100 100 100 0 21 NSSinag 983 0 0 100 100 100 0 22 4WS 124 0 0 100 100 100 0 23 2WS 1099 0 17 98,45 84,09 97,16 0,198 25 1WS 1247 0 2 100 100 100 0 27 NSDabrav 1641 0 0 100 100 100 0 28 3WS 238 0 0 100 100 100 0 31 6WS 1760 0 8 99,55 90,91 98,86 0,05 33 eco Arch 12000 0 0 100 100 100 0 35 eco Vidb 3144 0 0 100 100 100 0

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 10/13 Table № 8 WMB OF ARCHAR AND VITBOL RIVER BASINS - VARIANT I.2

WATER DEMAND : IRRIGATION WATER SUPPLY, DOMESTIC WATER SUPPLY ( from Water Licences and Data of National Statistical Institute for 2004), INDUSTRIAL WATER SUPPLY (from Water Licences ) PERIOD ( 1961 – 2004) D A T A EXCEEDENCE PROBABILITY % W , Average Average start , average storage Node annual In In In Index Water user № demands З З volumes years months З [100m ] [100m ] [100m ] 4 NSBojuri 14829 11347 0 100 100 100 0 5 p3gWS 631 0 0 100 100 100 0 6 p6gWS 1606 0 0 100 100 100 0 10 p1gWS 2207 0 0 100 100 100 0 11 p2gl 1375 0 0 100 100 100 0 12 5WS 1932 0 0 100 100 100 0 14 NSRabish 108760 0 13429 87,65 70 85 7,203 16 9WS 631 0 0 100 100 100 0 17 8WS 1621 0 0 100 100 100 0 20 7WS 317 0 0 100 100 100 0 21 NSSinag 1271 0 0 100 100 100 0 22 4WS 124 0 0 100 100 100 0 23 2WS 1099 0 25 97,73 80 95,83 0,27 25 1WS 1247 0 0 100 100 100 0 27 NSDabrav 2114 0 0 100 100 100 0 28 3WS 238 0 0 100 100 100 0 31 6WS 1760 0 8 99,55 90 98,33 0,022 33 eco Arch 12000 0 0 100 100 100 0 35 eco Vidb 3144 0 0 100 100 100 0

Table № 9 WMB OF ARCHAR AND VITBOL RIVER BASINS - VARIANT III.1

WATER DEMAND : IRRIGATION WATER SUPPLY, DOMESTIC WATER SUPPLY ( from Water Licences and Data of National Statistical Institute for 2004), INDUSTRIAL WATER SUPPLY (from Water Licences ) PERIOD ( 1961 – 2004) D A T A EXCEEDENCE PROBABILITY % W , Average Average start , average storage Node annual In In In Index Water user № demands З З volumes years months З [100m ] [100m ] [100m ] 4 NSBojuri 14829 11232 0 100 100 100 0 5 p3gWS 631 0 0 100 100 100 0 6 p6gWS 1606 0 0 100 100 100 0 10 p1gWS 2207 0 0 100 100 100 0 11 p2gl 1375 0 0 100 100 100 0 12 5WS 2934 0 0 100 100 100 0 14 NSRabish 108760 0 14224 86,92 70 83,33 7,444 16 9WS 1145 0 0 100 100 100 0 17 8WS 2227 0 0 100 100 100 0 20 7WS 425 0 0 100 100 100 0 21 NSSinag 1271 0 0 100 100 100 0 22 4WS 169 0 0 100 100 100 0 23 2WS 1354 0 40 97,05 70 94,17 0,423 25 1WS 1540 0 0 100 100 100 0 27 NSDabrav 2114 0 0 100 100 100 0 28 3WS 301 0 0 100 100 100 0 31 6WS 2783 0 51 98,17 80 95,83 0,191 33 eco Arch 12000 0 0 100 100 100 0 35 eco Vidb 3144 0 0 100 100 100 0

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 11/13

Analyses the results of WMB

In Sub-variant I.1, Sub-variant I.2 and Sub-variant III.1, the needs of every user are guaranteed completely, only three nodes have the following exceedence probability:

Node 14(NS Rabish)- Irrigation water supply (IF”Rabisha”);

Node 23(2WS) - Domestic water supply ( DWS) (for villages and towns from municipality Belogradchik, Archar river basin, the region of Oshane village);

Node 31(2WS) - Domestic water supply ( DWS) (for villages and towns from municipalities Dimovo and Makresh, the region of Bela village).

Sub-variant I.1 : Node 14 • Exceedence probability in volume - 96.37 %; • Exceedence probability in years - 93.18 %; • Exceedence probability in months - 95.83 %; Node 23 • Exceedence probability in volume - 98.454 %; • Exceedence probability in years - 84.09 %; • Exceedence probability in months - 97.16 %; Node 31 • Exceedence probability in volume - 99.55 %; • Exceedence probability in years - 90.91 %; • Exceedence probability in months - 98.86 %; Sub-variant I.2.: Node 14 • Exceedence probability in volume - 87.65 %; • Exceedence probability in years - 70 %; • Exceedence probability in months - 85 % ; Node 23 • Exceedence probability in volume - 97.73 %; • Exceedence probability in years - 80 %; • Exceedence probability in months - 95.83 %;

Node 31 • Exceedence probability in volume - 99.55 %; • Exceedence probability in years - 90 %; • Exceedence probability in months - 98.33 %; Sub-variant III.1.: Node 14 • Exceedence probability in volume - 86.92 %; • Exceedence probability in years - 70 %; • Exceedence probability in months - 83.33 %; Node 23 • Exceedence probability in volume - 97.05 %; • Exceedence probability in years - 70 %; • Exceedence probability in months - 94.17 %; Node 31 • Exceedence probability in volume - 98.17 %; • Exceedence probability in years - 80 %; • Exceedence probability in months - 95.83 %;

As it is seen from the disposed results for Archar and Vidbol river basins , the developed variants for WMB (Sub-variant I.1, Sub-variant I.2 and Sub-variant III.1) showed that the water use of every user is guaranteed in the limits of accepted for the country normative exceedence probability : for Irrigation –

BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May 2008 12/13 75%; Domestic water supply and Industrial water supply – 95-98%. In the points where there are shortages of water, they are not big and appeared mainly in outlets from stream water for Domestic water supply (totally their are 2) and in one Irrigation system. This is the case in: - water outlet for Domestic water supply of the villages from the municipality Belogradchik in the region of Oshane village (Archar and Oshane dere river basins), but only for exceedence probability in years in the three Sub-variants ( 84.09%; 80%; 70%); - water outlet for Domestic water supply of the villages from the municipalities Dimovo and Makresh in the region of Bela village (Archar river basin), for exceedence probability in years in the three Sub-variants( 90.91%; 90%; 80%); - IF”Rabisha” (takes water from “Rabisha” reservoir – volume 42 mln.m3 with inflow to it around 10 mln.m3 /year, with Irrigated areas – 32 816 dka and average water use in the dry period 10,8 mln.m3 ), with for exceedence probability in years in Sub-variant I.2. (70%) and Sub- variant III.1 - in years and months ( 70%; 70%; 83.33%). The average shortage in these Sub- variants is smaller than 13.1 % from the needs.

Conclusion, deductions and recommendations

The conducted experiments for WMB have the aim to give an idea in what stage the expected water use till 2015 (with issued water licences and without them) in these river basins exhausts the available water resource, are there necessary restrictions in issuing of new water llicences and whether is possible in the future to include new users. The developed variants for WMB for Archar and Vidbol river basins showed that every water user with very few exceptions is guaranteed according their normative exceedence probabilities. It is necessary to underlined that the received values in Sub-variant I.2 are concerning for chosen very dry 10 year period (for river flow with exceedence probability 97%), and in Sub- variant III.1., the percentage of the accepted water losses in the system is very high (60%), which is a reserve and leads to over security in guarantying the needs of the water users in the scheme and also leads to over the shortage. That explains the obtained shortages in these water outlets. The determination of a shortage in a node from the system means that there is comes to the front restriction of water users needs. In the case this restriction, although is not big, is a signal that it is exciting a problem in the normal water supply. The obtained shortages in the developed variants of WMB for Archar and Vidbol river basins can be liquidated or decreased. The important thing is that there are not nodes with drastic disturbances, inadmissible shortages in it and conflict of users interests, which could be an obstacle for issuing new water licences. It is understood that after including a new user is necessary a new decision of WMB for these river basins. In developing WMB for a river basin I s important not only the quantity assessment of the main subjects (flow - water demand), but also the situated locality of the users, the water outlets and hydro technical facilities, which are binded in developed mathematical models. Every change in the input of the model (resource, water use, mutual ties), requires a new developing of WMB in the river basins, i.e. WMB is a result, a decision based on the preliminary scenario( for the item, the kind, the needs, the size and the locality of the users and the facilities through which the resource goes to the users). That way WMB can only make a control of the possibility of including or excluding a user. With the developed WMB could be watch the condition of the river basin and its developing in the time. In conclusion it is need to underline that in the present and in the future 10-15 years in the region of Archar and Vidbol river basins can be guaranteed the water use of the different users in the limits of their normative exceedence probabilities, if the water losses in the system are reduced (water supply and sewerage system network) and if the available water resources are used properly and ruled rational, according the new economical, political and ecological requirements in the country.

Reference St.Yancheva, M.Temelkova , A.Yordanova (2007) Water resources use and water management balance of river basins in north-western Bulgaria-, 2 nd International Conference and exhibition of water resources, technologies and services BULAQUA, 6-7 June 2007 Sofia, Republic of Bulgaria. St.Yancheva at all. ( 2006 ) Water resources use and water management balances in Ogosta river basin and the river basins on the west of Ogosta (Contract № 10/2//11.03.2006 between Ministry of ecology and water and Institute of water problems, Bulgarian Academy of Sciences)(in bulgarian). Archive of Institute of water problems, Sofia. Santurgian at all. ( 2000 ) General schemes for water use in the river basins (Contract № 10/2//11.03. 2006 between Ministry of ecology and water and Institute of water problems, Bulgarian Academy of Sciences)(in bulgarian). Archive of Institute of water problems, Sofia

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