Hydro Power Cascades and Dams

IAOEIIAEIA
NATSIONALNA
AEAEOExANEA
ELEKTRICHESKA
EIIIAIE AAA
KOMPANIA EAD
Oeaiaiaaeeie eaneaae e yciaee
Hydro Power Cascades and Dams
1040 Nioey
1040 Sofia, Bulgaria
oe. Aaneao 5
5, Veslets Str.
oae. (02) 926 36 36
tel: (+359 2) 926 36 36
oaen (02) 987 25 50, 980 12 43
fax: (+359 2) 987 25 50, 980 12 43
http://www.nek.bg
http://www.nek.bg
aioaeeea Aueaaey
Republic of Bulgaria

---

(c) 2007, Iaoeiiaeia aeaeoe/anea eiiiaiey AAA
(c) 2007, Natsionalna Elektricheska Kompania EAD

---

OAIA
INTRODUCTION
Aucioi acaeoea ia yciaeiioi noieoaenoai
The fast development of dams construction in Bulgaria
a Aueaaey iac iaoaanaooa aiaeie ia ieiaeey aae
in the fifties of the past century necessitated
iaeaaa nucaaaaiaoi ia niaoeaeeceaia iaaiecaoey
the establishment of a special organization for technical
ca oaoie/anea e noiiainea aenieiaoaoey ia aieaieoa
operation and maintenance of the large dams and
yciaee e eaneaae a iaoaoa noaia. Ii oace ie/eia
cascades in our country. For the purpose, by a decision
n Iinoaiiaeaiea ia Ieienoaneey nuaao io yioae
of the Council of Ministers issued in January 1954,
1954 a. eui oiaaaaoiioi Ieienoanoai ia
a state organization was established to the Ministry
aeaeoeoeeaoeyoa a noiieaia aaaiinoaaia
of Electrification active by that time. Today this
iaaiecaoey, aiaoiioi iaaieyoea ciaee
establishment is called Dams and Cascades Enterprise.
e eaneaae.
That was the beginning of an organized technical
Oaea na iinoaay ia/aeioi ia iaaieceaiey
oaoie/anee eiioie auoo nunoiyieaoi e neaoiinooa
monitoring of the condition and security of such
ia oace ecee/eoaeii aaaeie ca eeiiiieeaoa ia
hydraulic facilities, which are of extreme importance
noaiaoa e a nuuioi aaia ioaiaiie e iioaioeaeii
for the country economy and at the same time hide
iianie nuiuaeaiey, oyoiaoa aenieiaoaoey,
a potential risk and require a lot of responsibility with
iiaauaeaia e aiiio, aoaeoeaiioi e aoeiiaeii
respect to their operation and maintenance, as well
eciiecaaia ia ineuaieoa aiaie anone a aioaeeea
as in regard to the rational and efficient utilization of
Aueaaey.
the scarce water resources of the Republic of Bulgaria.
Iaaieyoea ciaee e eaneaae noiiaienaa 43
The Dams & Cascades Enterprise operates and maintains
yciaeie noaie, 671 ei ooiaee e eaiaee e iaa 500
43 dams, 671 km of tunnels and channels and over 500
aiaioaauaiey. Oiaa na ecee/eoaeii neuie, neiaeie
water catchments. These are various and extremely
e aciiiaacie nuiuaeaiey, eui /eyoi aenieiaoaoey
expensive and complex facilities, which operation
na iinoaayo aeniee eceneaaiey ca neaoiino
necessitates a high degree of security and economy.
e eeiiiie/iino.
The total storage volume of the dams operated by
Iaueyo caaeai iaai ia noiiaienaaieoa io
the D&C Enterprise amounts to 3.5 billion m3, which
iaaieyoeaoi yciaee a 3.5 iea. i3, eiaoi
presents 55% of the total regulated volume of the water
iaanoaaeyaa 55% io iauey aaoeeai iaai
storage reservoirs in our country.
ia aiaioaieeeuaoa ia iaoaoa noaia.
The hydro power sites built in Bulgaria are characterized
Ioee/eoaeai aaeaa ia ecaaaaieoa oeaiaiaaeeie
by their complex application. Besides for the purposes
iaaeoe a aioaeeea Aueaaey a oyoiioi eiiieaenii
of energy generation, their waters are also used
iaaiacia/aiea. Inaai ca aiaaiaiaea aiaeoa ei
for irrigation and water supply, for flood protection,
na eciiecaao e ca iaiiyaaia, aiainiaaayaaia, aiaa
for river valleys watering, for fishing and various sports
nauo iaaiaiaieyoa, iaiaiyaaia ia iia/eyoa,
activities.
eaieia e niio.

---

Iaoeiiaeia aeaeoe/anea eiiiaiey AAA
Oeaiaiaaeeie eaneaae e yciaee
Ca iiiecioaiyaaia ia aiaieoa anone ca
In order to utilize the waters for energy generation,
aiaaiaiaea iia yciaeeoa na ecaaaaie 35
35 hydro power plants with 2811 MW total installed
aiaiiaeaeoe/anee oaioaee n iaua einoaeeaia
capacity have been built below reservoirs. Though their
iiuiino 2811 IAo. Auiaee /a oaoieyo ieiin
contribution to the total electricity generation is small,
a iauioi aeaeoiiiecaianoai a iaeue, cia/aieaoi
their importance is first of all expressed in peak load
ei na iaoneaay iaae ane/ei io iiaiaiaoi ia
covering and stability ensuring in the Electric Power
auoiaioi iaoiaaaaia e nucaaaaiaoi ia noaaeeiino
System.
a aiaainenoaiaoa.
During its functioning for more than half a century
A naiyoa iaa iieiaei aaeiaia aaeiino iaaieyoea
the Dams & Cascades Enterprise has been performing
ciaee e eaneaae a eciueiyaaei e eciueiyaa
the following main tasks:
neaaieoa ii-aaaeie caaa/e:
Technical monitoring of the stability and operational
Oaoie/anee eiioie auoo noaaeeeoaoa e
reliability of the dams, the pressure and free-flow
aenieiaoaoeiiiaoa neaoiino ia yciaeieoa
derivations and the other hydraulic facilities.
noaie, iaiiieoa e aaciaiiieoa aaeaaoee
Operation, repair and maintenance of hydraulic
e aoaeoa oeaioaoie/anee nuiuaeaiey.
facilities.
Aenieiaoaoey, iiaauaeaia e aiiio
New construction of facilities related with the technical
ia oeaioaoie/aneeoa nuiuaeaiey.
operation and maintenance.
Ecauoaaia ia iiai noieoaenoai aua aucea
Maximum water catchment and their efficient
n oaoie/aneaoa e noiiaineaoa aenieiaoaoey.
utilization.
Iaeneiaeii oeaayia e aoaeoeaii eciiecaaia
Complex hydrostatic and hydrodynamic processes
ia aiaeoa.
and phenomena are observed in the dams, which
A yciaeieoa noaie na acaeaao neiaeie
necessitates permanent monitoring, measurements,
oeainoaoe/ie e oeaiaeiaie/ie iioane e
technical control and analyses of their condition.
yaeaiey, eieoi iaeaaao iinoiyiie iaaeaaiey,
This main activity of the D&C Enterprise is performed
eciaaaiey, oaoie/anee eiioie e aiaeec ia
according to technical monitoring programs, which
oyoiioi nunoiyiea. Oace iniiaia aaeiino ia
are periodically updated depending on the needs.
iaaieyoeaoi na eciueiyaa a nuioaaonoaea
The following phenomena are subject to monitoring
n iiaaie ca oaoie/anee eiioie, eieoi
and measurement:
a caaeneiino io ioaeaeoa na aeooaeeceao
deformations in the dam body, the foundations
iaeiae/ii. Iaaiao ia iaaeaaiea e eciaaaia na:
and the slopes;
aaoiiaoee ia yciaeieoa noaie, iniiaeoa
seepage through the dam body, the foundations
e neaoiaaoa ei;
and the slopes;
oeeoaoey iac yciaeieoa noaie, iniiaeoa
chemical and mechanical suffosion of waters;
e neaoiaaoa ei;
water economic, hydraulic and meteorological
oeie/anea e iaoaie/anea nooicey ia aiaeoa;
parameters related with waters complex analyses
aiainoiiainee, oeaieiaeee e iaoaiieiaeee
and their rational utilization;
iaaiaoe, naucaie n eiiieaenieoa aiaeece
sediments and silt in the water storage reservoirs
e aoeiiaeiioi eciiecaaia ia aiaeoa;
and erosion processes developing there.
ioeiaeaie iaiine aua aiaioaieeeuaoa
e acaeaaue na aiceiiie iioane.
2

---

Natsionalna Elektricheska Kompania EAD
Hydro Power Cascades and Dams
Ca ecauoaaiaoi ia ane/ee oace iaaeaaiey
Highly professional, state-of-the art equipment is applied
e eciaaaiey na eciiecaa nuaaiaiia aiaaooa
for such measurements and monitoring. The D&C
ia aeniei iioaneiiaeii ieai. Iaaieyoeaoi
Enterprise is equipped with geodetic measurement
a nuiuaeaii n oaae ca aaiaace/anee eciaaaiey,
devices and remote measurement devices for measuring
ieaie ca aenoaioeiiii eciaaaia e io/eoaia ia
the parameters of deformation and seepage processes
iaaiaoeoa ia aaoiiaoeiiieoa e oeeoaoeiiieoa
and phenomena observed in the dams. It is also
iioane e yaeaiey a yciaeieoa noaie, aaoiiaoe/ie
provided with automatic meteorological stations,
iaoaiieiae/ie noaioee, ieaiiaie oaaae,
level gauges, flow meters for pressure and free-flow
acoiaiiae ca iaiiie e aaciaiiie nuiuaeaiey,
facilities, hydrometric propellers, depth-sounders
oeaiiaoe/ie aeoea, aoieio n GPS nenoaia.
with GPS systems.
Iaaiecaoeiiiaoa nooeooa ia iaaieyoea ciaee
The organizational structure of the Dams & Cascades
e eaneaae aee/aa oaioaeiioi oiaaeaiea,
Enterprise includes a Head Office, 16 Dam Areas
16 yciaeie aeiia e aaa aiiioie aace.
and Maintenance Bases.
Ca inuuanoayaaia ia aaeiinooa ii iaaeaaieyoa
The D&C Enterprise has laboratories equipped for:
e eciaaaieyoa iaaieyoeaoi eia iaioaaaie
monitoring of special control and measurement
eaaiaoiee ii:
devices;
eiioie ia niaoeaeeceaie eiioieii-
chemical analyses of suffosion processes;
eciaaaoaeie ieaie;
photo and video documentation of phenomena
oeie/anee aiaeec ca nooiceiiie iioane;
and processes, emergency situations, etc.
oioi e aeaai aieoiaioeaia ia yaeaieyoa
For the purposes of economic and rational utilization
e iioaneoa, aaaeeie neooaoee e aoae.
of waters, the D&C Enterprise has a hydro-meteorological
Ca oaeeoa ia noiiaineaoa aenieiaoaoey e
network built, which includes 156 hydrometric,
aoeiiaeiioi eciiecaaia ia aiaeoa iaaieyoeaoi
16 climatic, 41 rainfall measuring and 12 snowfall
eia ecaaaaia aaaiinoaaia oeaiiaoaiieiae/ia
measuring stations.
iaaea, aee/aaua 156 oeaiiaoe/ie, 16
eeeiaoe/ie, 41 auaeaiiaie e 12 niaaiiaie noaioee.
Aiaaaia a aaoiiaoeceaia eioiiaoeiiia
nenoaia (AEN) ca ecaioayia ia aaeaaiaaiey aiaai
An automated information system (AIS) for estimation
aaeain n oe oeia iiaoee a yciaeieoa aeiie
of the daily water balance by using of three modular
ia eaneaaa Aaa, nuioaaoieoa AAO e a oiaaeaieaoi.
types has been implemented in the Dam Areas of Arda
Cascade, in the respective HPPs and in the Head Office.
Iaaieyoea ciaee e eaneaae aciieaaa n aiaa
iaioaaai oaoie/anee eaaeiao n aoeaie iaoaeaee
The Dams & Cascades Enterprise has a well-equipped
io iio/aaiaoi, iiaeoeaiaoi, noieoaenoaioi
technical center with records of studies, designs,
e aenieiaoaoeyoa, oaoie/anee ianiioe e aiaeece
construction works and facilities operation, technical
ca nunoiyieaoi ia yciaeieoa noaie e
passports and analyses of the dams condition and
nenoaiaoeceaia oaoie/anea aeaeeioaea.
a systematic technical library.
3

---

Iaoeiiaeia aeaeoe/anea eiiiaiey AAA
Oeaiaiaaeeie eaneaae e yciaee
A yciaeieoa aeiie eia noiieaie aiiioie
The Dam Areas are provided with maintenance
aoie, iaiaoiaeieoa niaoeaeenoe e nuioaaoiaoa
teams, appropriate experts and bases for monitoring
iaoaeaeia aaca ca ecauoaaia ia iiaaoeaieoa
and measurements in the dams, for current facilities
iaaeaaiey e eciaaaiey a yciaeieoa noaie,
maintenance and necessary repair and restoration works.
oaeouioi iiaauaeaia ia nuiuaeaieyoa e
Since 2000 the Enterprise has been conducting
ecauoaaiaoi ia iaeaaaueoa na aiiioii-
a permanent policy for special training of the staff
aucnoaiiaeoaeie aaioe.
in the high mountainous regions and for operation
Io 2000 a. iaaieyoeaoi iiaaaeaa nenoaiia
under heavy winter conditions.
iieeoeea ca iiaaioiaea e niaoeaeeceaii iao/aiea
State-of-the art equipment has been provided. The
ia /ano io ianiiaea ia aenieiieaieineeoa aeiie
training is under the guidance of professional life savers
e oiaaeaieaoi ca aaioa a oaaeee ceiie oneiaey.
in the mountains. In this way the work under heavy winter
Ineaoaii a nuaaiaiii iaioaaaia e aeeieiaea.
conditions has been raised to a substantially new level.
Iiaaioiaeaoa na iiaaaeaa io iioaneiiaeie
The training and the equipment of the staff which
ieaieinee nianeoaee. Ii oice ia/ei aaioaoa
operates the hydraulic facilities and performs the
a ooaieoa ceiie oneiaey aeniei a ieaieieoa
measurements to a great extent ensure safe and reliable
na ecaeaia ia ea/anoaaii iiai aaieua. Iiaaioiaeaoa
fulfillment of the staffs duties.
e iaioaaaiaoi ia ianiiaea, ianeoaeaau
The activities in the Dam Areas are supported by
oeaioaoie/aneeoa nuiuaeaiey e ecauoaau
two maintenance and transport bases, provided with
eciaaaiey, a aieyia noaiai aaaioea neaoiinooa
appropriate machines, equipment, transport facilities
e aaciianiinooa ie eciueiaiea ia neoaeaaieoa
and mobile repair workshops.
io caaueaeaiey.
Aaeiinooa ia yciaeieoa aeiie na iiaiiiaaa
io aaaoa aiiioii-oainiioie aace, aciieaaaue
n iaiaoiaeiaoa iaoaiecaoey, oainiio e iiaaeaeie
aaioeeieoe ca aiiio ia nuiuaeaieyoa.
Working teams have been formed in these bases
for performing of drilling, grouting and shotcrete works.
Where underwater works are required, they are fulfilled
by special teams of divers.
By its activities the Dams & Cascades Enterprise has
Eui oyo eia iaaieceaie niaoeaeeceaie aoie
achieved a good reputation and has obtained a leading
ca ecauoaaia ia niiaaaeii-eiaeaeoeiiie e oieaoie
role in our country in the sphere of hydraulic facilities
aaioe. Ca iaeaaaueoa na iiaaiaie aaioe na iiecaao
operation and maintenance. It is a member of the
niaoeaeeceaie aiaieacie aoie.
Bulgarian Committee of Large Dams.
Nun naiyoa aaeiino iaaieyoea ciaee e eaneaae
na a ooauaeei e eia aiaaua iey a iaoaoa noaia
a iaeanooa ia iiaauaeaiaoi e aenieiaoaoeyoa
ia oeaioaoie/aneeoa nuiuaeaiey. Oi a eieaeoeaai
/eai ia Aueaaneioi aoaeanoai ia aieaieoa yciaee.
4

---

Natsionalna Elektricheska Kompania EAD
Hydro Power Cascades and Dams
EANEAAA AAEIAEAI
BELMEKEN SESTRIMO
NANOEII xAEA
CHAIRA HYDRO POWER CASCADE
Noaia ia eaneaaa Aaeiaeai Nanoeii xaea Scheme of Belmeken Sestrimo Chaira Hydro Power Cascade
Aaa Nanoeii Gara Sestrimo
NA Iaeoa 1200 Maritsa 1200 Collecting Derivation
AAO Iiieia Eeenoa Momina Klisoura HPP
Q=9.69 eoa. i/n Q=9.69 m3/s
2 aoie 2 units
L=20 702 i L=20 702 m
Iiuiino 120 IAo Capacity 120 MW
n. Iiieia Eeenoa Momina Klisoura Village
c. Noaieiae aaaee Stankovi Baraki Reservoir
Iau iaai=0.42 iei. eoa. i Ootal storage 0.42 mln m3
Aiai ecaaieoae Momina Klisoura
Caeyoa ieiu=0.022 ea. ei Water surface area 0.022 km2
Iiieia eeenoa Upper Reservoir
IAAAO Aaeiaeai Belmeken PSHPP
n. Nanoeii Sestrimo Village
Aaa Aaeiai Belovo Railway Station
4 aoie 4 units
. Iaeoa Maritsa
Iiuiino 375 IAo Capacity 375 MW
AAO Nanoeii Sestrimo HPP
River
NA Iaeoa 1900 Maritsa 1900 Collecting Derivation
River
2 aoie n Q=13.6 eoa. i/n 2 units, Q=13.6 m3/s
Q=10.32 eoa. i/n Q=10.32 m3/s
c. noaia Dam
Kriva
Iiuiino 240 IAo Capacity 240 MW
L=20 767 i L=20 767 m
H=98 m
Eeaa
L=737.5 m
.
c. noaia Dam
H=85 m
NA xaenee Chairsky Collecting Derivation
c. Aaeiaeai Belmeken Reservoir
L=305.0 m
Q=4.97 eoa. i/n Q=4.97 m3/s
Iau iaai=144 iei. eoa. i Ootal storage 144 mln m3
L=16 004 i L=16 004 m
Caeyoa ieiu=4.531 ea. ei Water surface area 4.531 km2
River
c. noaia Dam
IAAAO xaea Chaira PSHPP
H=33.8 m
4 aoie 4 units
Yadenitsa
L=537.0 m
Iiuiino 864 IAo Capacity 864 MW
Riverc. noaia Dam
NA Aui/a Granchar Collecting Derivation
c. xaea Chaira Reservoir
aaieoa
Iskar H=50.7 m
Iau iaai=5.5 iei. eoa. i. Ootal storage 5.5 mln m3
.
Q=23.24 eoa. i/n Q=23.24 m3/s
.
Beli L=532.5 m
L=46 025 i L=46 025
Caeyoa ieiu=0.202 ea. ei Water surface area 0.202 km2
Aaooeoa
m
River
neu
NA aaieoa Yadenitsa Collecting Derivation
aaaneaai ooiae Reversible tunnel
e E
.
Rajavitsa
Q=2.164 eoa. i/n Q=2.164 m3/s
Q=4.12 eoa. i/n Q=4.12 m3/s
Eaaaa
Dautitsa
L=19 848 i L=19 848 m
L=2 800 i L=2 800 m
. Aae
Eaaaiaa LEGEND
Leave
River
uaeaaeoa
NA Aaeaoaeoa Dzhaferitsa Collecting Derivation
.
Q=0.64 eoa. i/n Q=0.64 m3/s
ciaeia noaia Dam
River
L=10 505 i L=10 505 m
AIA Iain pressure derivation
c. Aaee Eneu Beli Iskar Reservoir
Ooiae Tunnel
Iau iaai=15.08 iei. eoa. i Ootal storage 15.08 mln m3
R
iver
Eaiae Channel
Caeyoa ieiu=0.845 ea. ei Water surface area 0.845 km2
esta
Iuo Road
M
Ianaeaii iynoi Settlement
. Ayea
Ianoiino iaiea Yundola Resort
Eaioii Lodge
I
Cherna
anoa Byala M
Ianoa
esta River
. Ianoa Mesta River
xaia
A. Aaeeiaaa Velingrad
.
Eaneaaa Aaeiaeai Nanoeii xaea a iae-
Belmeken Sestrimo Chaira Hydro Power Cascade
aieaieyo, aciiiaacai e neiaeai oeaiaiaaeai
is the largest hydro power complex, varied
eiiieaen n iaua aiainaiia ieiu 457 ei2. Aeaaiioi
and compound, with a total water catchment area
e iaaiacia/aiea a iiecaianoai ia aeaeoe/anea
of 457 em2. It is mainly used for electricity generation,
aiaaey, iaiiyaaia e aiainiaaayaaia. A nenoaiaoa
irrigation and water supply. The cascade system
ia eaneaaaoa na aee/aie oe yciaea, aaa iiyna
consists of three main reservoirs, two zones of collecting
nuaeaoaeie aaeaaoee, /aoee aeaeoioaioaee
derivations, four power plants and two compensating
e aaa ecaaieoaey.
reservoirs.
OEAIAUCAE AAEIAEAI
BELMEKEN HYDRO POWER SITE
5

---

Iaoeiiaeia aeaeoe/anea eiiiaiey AAA
Oeaiaiaaeeie eaneaae e yciaee
Oeaiaucae Aaeiaeai a aciieiaeai a iae-aiiaoa
Belmeken Hydro Power Site is located at the highest
/ano ia eaneaaaoa e aee/aa yciae Aaeiaeai,
part of the cascade and consists of Belmeken Dam,
nuaeaoaeieoa aaeaaoee io iuaey iiyn, Iaeoa
the collecting derivations of the first zone, Maritsa 1900,
1900, Aui/a, Aaeaoaeoa e nuaeaoaeie
Granchar, Dzhaferitsa and the collecting derivations
aaeaaoee Aeaaiaaaaanea Aenoeoa, Eeeeia
Blagoevgradska Bistritsa, Iliina and Manastirska along
e Iaianoenea io iia/eaoi ia . Nooia, IAAAO
the valley of Strouma River, Belmeken PSHPP
Aaeiaeai e IAAAO xaea.
and Chaira PSHPP.
CIAE AAEIAEAI
BELMEKEN DAM
Aaia
Berm 1850
1850
Aaia 3 1886 Berm
Aaia
3 1886
2 1900 Berm
Aaia
2
1
1900
1914 Berm
Eiiia
1 1914
1923 Crest
Aaia
1923
1 1914
Aiaia
Berm
Aaia noaia
1
1850 Upstream
1914
Berm
face
1850
IAUE AAIIE
BASIC DATA
Ianoiiieiaeaiea
eea
Location
Rila Mountains
Iinoiai ia aea
Eeaa
Built on
Kriva River
Aiainaiia iaeano, ei2
219
Water catchment area, em2
219
Naaiiaiaeoai ieoie, i3/nae
242.50
Mean annual inflow, m3/s
242.50
Aiaeia ia iinoiyaaia
1974
Year of commissioning
1974
Iaaiacia/aiea
aeaeoiiiecaianoai
Use
electricity generation
Ecaaiyaaia ia aiaiaoa iana
iiiaiaiaeoii
Water masses regulation
perennial
AIAIOAIEEEUA
WATER STORAGE
Caaeai iaai, iei. i3
144.04
Total storage, mln m3
144.04
Iieacai iaai, iei. i3
141.16
Usable storage, mln m3
141.16
Iae-aeniei aiaii ieai, i
1921.0
Max water level, m
1921.0
Iae-aeniei aaioii aiaii ieai, i
1920.5
Max operating water level, m
1920.5
Iae-ienei aaioii aiaii ieai, i
1865.0
Min operating water level, m
1865.0
Caeyoa ieiu, ei2
4.531
Water surface area, km2
4.531
CIAEIA NOAIA
DAM
Oei
eaiaiiiianeiia
Type
rock-fill
Iioeaioeeoaoeiiia iaaaaa
aeeiaii yai
Waterproof component
clay core
Aeni/eia io iniiaaoa, i
88.2
Height from foundation, m
88.2
Aueaeeia ii eiiiaoa, i
737.5
Crest length, m
737.5
Eioa eiiia, i
1923.0
Crest level, m
1923.0
6

---

Natsionalna Elektricheska Kompania EAD
Hydro Power Cascades and Dams
IAEEAIEE
SPILLWAY
Oei
oaioay
Type
trench type
Aueaeeia/oeeia, i
19.00/3.00
Length/width, m
19.00/3.00
Iaeeaii aiaii eiee/anoai
Spillway discharge
ie iaeneiaeii aiaii ieai, i3/nae
14.00
at max water level, m3/s
14.00
INIIAIE ECIONEAOAEE
BOTTOM OUTLETS
aiiioai caoai
ainae eeaia
Maintenance valve
butterfly valve
aaioai caoai
Aaeiinuiia caoai
Operating valve
Johnsons slide valve
Iaua iiioneaoaeia niiniaiino, i3/nae
8.0
Total discharge capacity, m3/s
8.0
Aie ia ecioneaoaeeoa
1
Number of outlets
1
Neooaoey ia eiioanoaia "Aaeiaeai" Layout of Belmeken Saddle Dam
Iaeoaeia oaooa Measuring pit
Taioaai iaeeaiee
Trench-type spillway
Iauaa Scale
0 20 40 60 80
Aiaia noaia Upstream face
EIIOANOAIA
SADDLE DAM
Oei
caiiiianeiia io aon
Type
earth-fill dam made of disintegrated granite
Iioeaioeeoaoeiiia iaaaaa
aeeiaii yai
Waterproof component
clay core
Aeni/eia io iniiaaoa, i
23.1
Height from foundation, m
23.1
Aueaeeia ii eiiiaoa, i
537.0
Crest length, m
537.0
Eioa eiiia, i
1922.80
Crest level, m
1922.80
IAAAO AAEIAEAI
BELMEKEN PSHPP
Oei ia oaioaeaoa
aaeaaoeiiia
Power plant type
derivation type
Iaa ia aiaaoa, i
730
Water head, m
730
Iaeneiaeii aiaii
Max spillway
eiee/anoai, i3/nae
12.5-O 6.86-I
discharge, m3/s
12.5-T 6.86-P
Aie ia aaaaaoeoa-iiiie
3-O 2-I+O
Number of units-pumps
3-T 2-P+T
Oei ia ooaeieoa
Iaeoii
Turbine type
Pelton
Einoaeeaia iiuiino, IAo
375-O 104-I
Installed capacity, MW
375-T 104-P
Naaiiaiaeoii aeaeiiiecaianoai, AAo/
331
Mean annual electricity generation, GWh
331
7

---

Iaoeiiaeia aeaeoe/anea eiiiaiey AAA
Oeaiaiaaeeie eaneaae e yciaee
IAAAO xAEA
CHAIRA PSHPP
Iuaeyo aaaaao ia oaioaeaoa a iiecaaaai io
The first unit of this power plant was manufactured
Oioeaa, iiiey, a inoaiaeeoa oe a aueaaneeoa
by Toshiba, Japan, and the other three units were
caaiae Aaioaia AA, Ieaaai e Aeiii CAI,
manufactured by the Bulgarian factories Vaptsarov,
Nioey ii yiiinea aieoiaioaoey e eiioie
Pleven and Elprom ZEM, Sofia, in compliance with the
ia ea/anoaioi.
Japanese documentation and under Japanese quality control.
Io 1995 a. na a aenieiaoaoey I e II aaaaao,
Units I and II have been in operation since 1995
a io 1999 a. III e IV aaaaao, n eiaoi na ainoeaa
and units III and IV since 1999, thus the full capacity
iueia iiuiino ia IAAAO xaea.
of Chaira PSHPP has been reached.
Iaoeiiaoa caea ia IAAAO xaea a aciieiaeaia
The machine hall of Chaira PSHPP is located in
a iiacaiia eaaaia n aciae 113.5/22.5/43 i.
an underground cavern with dimensions 113.5/22.5/43 m.
Aiie aiaie eoee
Upstream surge tanks
NA Aui/a Granchar Collecting Derivation
c. Aaeiaeai Belmeken Dam
Eiioanoaia Aaeiaeai Belmeken Saddle Dam
Ainae eeaia
VI iiciao Access Tunnel VI
Butterfly valve
Aiaaoia eaiaa
Valve chamber
II iiciao Access Tunnel II
AIA ia IAAAO Aaeiaeai
Aieie aiaie eoee
Main pressure derivation of Belmeken PSHPP
Downstream surge tanks
NA xaenea
Chairska Collecting Derivation
c. xaea
Chaira Dam
NA Iaeoa 1200
Maritsa 1200 Collecting Derivation
Aeaaai aoia Main entry
IAAAO Aaeiaeai Belmeken PSHPP
c. Noaieiae aaaee Stankovi Baraki Dam
Iaiiai ooiae
IAAAO xaea Chaira PSHPP
Pressure tunnel
Eui AAO "Nanoeii" Towards Sestrimo HPP
8

---