current progress at the belo monte hydro project, …...of the first turbines during the time...

The Belo Monte project on the Xingu river is inthe middle of the Amazon jungle, in the state ofPará, in Brazil’s northern region close to

Altamira and Vitoria do Xingu cities, and about 800km from Belem, the capital city of the state (see Fig.1). The plant is about 3000 km from several majorBrazilian cities, such as São Paulo and Rio de Janeiro.The main objective of the project is power generation,with an installed capacity of 11 233.1 MW and anaverage 4571 MW of firm energy.

Norte Energia SA is the developer of the project. Thestate-owned power company Eletrobras, directly andthrough its subsidiaries Eletronorte and CHESF, con-trols a 49.98 per cent stake in the consortium. Otherimportant partners are stakeholders of the consortium,such as FUNCEF (10 per cent), Petros (10 per cent),Neoenergia (10 per cent), Aliança Norte Energia SA(Vale, CEMIG and Sinobras, 10 per cent), AmazoniaEnergia SA (Light and CEMIG, 9.77 per cent) andJ. Maluceli Energia SA (0.25 per cent).

1. Background Since the late 1970s, the original project concept hasundergone several modifications, to mitigate socialand environmental impacts. This was done to maintainthe living conditions of indigenous groups and com-munities who live in the area surrounding the plant,known as ‘Big Bend’ on the Xingu river, a stretch ofreduced flow (SRF). To comply with strong environ-mental constraints, Belo Monte was planned to operateas a run-of-river plant, resulting in a significant reduc-tion in the size of the reservoir and consequently thearea to be flooded.

While the Brazilian average flooded area forhydropower is 0.49 km2 per MW installed, the ratio forBelo Monte is only 0.04 km2 per MW installed, the thirdlowest ratio in Brazil. In addition, of the 478 km2 offlooded area of both reservoirs, about 228 km2 or 47.7per cent corresponds to the original riverbed. The designof Belo Monte was optimized to reduce environmentalimpacts, as compared with other hydropower, whichleads to improved and sustainable models and repre-sents good practice for a hydro project.

Necessary steps have been taken to avoid floodingindigenous lands, which remain unaffected by thedam, construction sites, access roads and other engi-neering structures required for the project. For theindigenous communities, and those who use the Xinguriver for fishing or transport, the Belo Monte projecthas created solutions to enable boats to pass throughthe dam, as well as the construction of a fish passagesystem.

As well as a stretch of approximately 100 km down-stream of the main dam, the SRF of the Xingu riverhas an ecological hydrograph consensus with the pur-pose of generation of energy and the adoption of ahydrograph that meets the maintenance and continuityof ecological processes (terrestrial and aquatic ecosys-tems) and navigability.

Currently, the civil works are concentrated on the place-ment of the secondary concrete for assembly of theremaining generating units. At present (December 2018),the civil works are 98.5 per cent complete and 67.3 percent of the total installed capacity has been implemented(7566.4 MW from 18 generating units, six bulb and 12Francis turbines). The first two turbines went online inApril 2016. The main power station will be completed byDecember 2019. The plant is also responsible for supply-ing electricity for the interconnected national grid, boththe systems in the North and South/Southeast, with trans-mission lines of 500 kV/880 kV.

The construction of a huge hydropower plant in themiddle of the Amazon jungle has been a very challeng-ing project. From December to June, heavy rains andfloods occur, with average rainfall of 2200 mm/year,increasing the difficulties and logistical problems. Mostof the suppliers of materials, equipment and processedfood are located in other regions, mainly in Belem, cap-ital city of the state, and in the southeast of Brazil.

Hydropower & Dams Issue Six, 2018 29

Current progress at the Belo Montehydro project, Brazil O.M. Bandeira and J.B. de Menezes, Norte Energia, Brazil

The Belo Monte run-of-river powerplant is under construction on the lower reach of the Xingu river, in northern Brazil. When completed inDecember 2019, Belo Monte will have 24 generating units with a total installed capacity of 11 233.1 MW, making it the largest whollyBrazilian hydropower plant and the fourth in the world, in terms of installed capacity. Since April 2016, 7566.4 MW have already beeninstalled with six bulb and 12 Francis turbines in commercial operation. The authors give the latest update on the achievements of the

project, along with a description of the Belo Monte project as a whole.

Fig. 1. Location ofthe Belo Montescheme.

Simultaneously with the work, it was necessary toimprove river access and, by building a load trans-ship-ment station, the regional highway network was alsoimproved and expanded. More than is the case at otherhydro projects in Brazil, it was necessary to attract andkeep workers, by offering both direct and indirect extrabenefits, namely building a village with complete withstandard educational, health and leisure facilities, andbreak times for workers who have families living away.

The civil contractor decided to implement four sepa-rate construction sites, with a distance between themof up to 40 km, to achieve high rates of excavation andplacement of earthfill and rockfill, with a tight sched-ule, and to manage the complex logistics for the sup-ply and movement of the materials on the job site aswell as the ability to perform maintenance tasks.

The record-breaking outputs achieved for soil androck excavation, as well as in earthfill and rockfillservices, had reached 6.6 ¥ 106 m³ (soil excavation),2.5 ¥ 106 m3 (rock excavation) and 6.28 ¥ 106 m3

(earthfill and rockfill) by July 2015.As well as the civil contractor, 37 000 workers and

3800 light and heavy pieces of equipment were mobi-lized at the peak of the construction. The civil worksneeded to allow for the start of the filling of the mainand intermediate reservoirs, which have been accom-plished in a record time of 4.2 years.

The project is modern and fully committed to theprinciples of technical and economic feasibility, aswell as minimal social and environmental impacts.

The statistics relating to Belo Monte are impressive,but the project cannot be judged only from the point ofview of energy generation. It should be highlighted thatmore than 5000 socio-environmental steps have beentaken, which have promoted true social transformationand have contributed to sustainable development.

2. The general arrangement of the projectThe arrangement of the project is different from anyother already built in Brazil or elsewhere. As men-tioneds the four construction sites are some distancefrom each other. These include the Pimental dam,which forms the main reservoir (359 km2) and divertsthe water of the Xingu river into a rock-lined powercanal, considered the largest in capacity for energygeneration, which conveys 13 950 m3/s of water to anintermediate reservoir with an area of 119 km2 thatfeeds an 11 000 MW powerhouse at the Belo Montesite (see Fig. 2). There are six earthfill and rockfilldams and 30 dykes (some these could be consideredlarge dams). Completing the project, there are twopowerhouses with 24 generatings units, six horizon-tal Kaplan bulb turbines at Pimental (38.85 MWeach) and 18 Francis turbines at Belo Monte, (611.1MW each). There is also a spillway with 18 radialgatesand a stilling basin and a discharge capacity of62 000m3/s.

3. Pimental siteThe construction of the Pimental dam was a very chal-lenging project as it was necessary to cross severalislands: Forno, Pimental, Marciana, Reynaldo andSerra, see Photo (a). The main dam was also con-structed across the Xingu river, 40 km downstreamfrom Altamira city with about 7 km of extension. Itforms the main reservoir (359 km2) and consists ofseveral major components (see Fig. 3) including: thelateral left dam; low head complementary power-house; and, a spillway with 18 radial gates.

Completing the arrangement are a dam linking thespillway with the Serra Island, right channel dam, twodykes, a transposition system for boats, from upstreamto downstream and vice versa, a fish transpositionchannel and a switchyard of 230 kV/69 kV.

The complementary powerhouse and spillwayrelease a minimum flow downstream, which varieseach month, to comply with the hydrograph of con-sensus for the SRF and to mitigate the socio-environ-mental impacts. During the wet season, this flow hasto be a minimum of 1100 m3/s in January, 8000 m3/s inApril, and 4000 m3/s in May. During the dry seasonthere has to be a minimum flow of 2000 m3/s in June,700 m3/s in October and a minimum of 900 m3/s in

30 Hydropower & Dams Issue Six, 2018

Fig. 2. Generalarrangement of theBelo Monte hydroproject.

(a) Crossing theXingu river at adistance of 7 km forthe construction ofthe main dam inPimental representeda significantchallenge.

Fig. 3. Arrangement of the Pimental site and its strucures.

December. A programme of regular water qualitymonitoring has also been implemented downstream ofthe dam to improve the quality of life of riparian andindigenous communities, as well as the maintenanceof biodiversity, navigability and the living conditionsof the populations on the SRF.

3.1 Diversion of the Xingu riverIn the first phase of the diversion of the Xingu river, toallow the construction of all concrete structures, thecentral canal of the river was closed by three coffer-dams, one upstream and two downstream betweenislands, and all the water from the Xingu river wasdiverted to the right channel, see Photo (b).

In the second phase of river diversion, to allow theconstruction of the right channel dam, two cofferdamsupstream and downstream closed off the right channel,diverting the Xingu river to the spillway which wasalmost completed.

Considering the short term for the construction of theright channel dam, with a high risk of delay for thebeginning of generation, there was a decision to con-struct the upstream cofferdam with the crest at el. 99 m,just 1 m below the crest of the final dam. This cofferdam,with a maximum height of 40 m, and an extension of 923m, enabled filling of the reservoir and start of operationof the first turbines during the time foreseen in the sched-ule. The right channel dam was constructed after, takingnearly a year, and reaching completion in October 2016.

3.2 The left lateral damThe left lateral dam, which interconnects the concretestructures with the left abutment, is 5100 m long, pass-ing over three large islands (Forno, Marciana andPimental); the section on Pimental is around 2900 mlong. In the stretches of the islands, the dam has ahomogeneous earth section, with an average height of14 m, supported by alluvial soils, and a rock cutofftrench was implemented to intercept the seepage flow.In the stretches of the Pimental and Marciana islands,the sealing trench was shifted upstream of the dam,where the alluvial layers are less thick (see Fig. 4). Inthe stretches of the canals, it has an average height of23 m and is supported by rock. In the section near theconcrete structures, the section is a rock formationwith a clay core, with the foundation in sound rock.

3.3 Right channel damThe right channel dam, located in the deepest sectionof the Xingu river, with a length of 714 m, has anearth/rock section in the centre, supported by soundrock, with a maximum height of 41 m, supported onsoil with homogeneous margins, supported in residualsoil of migmatite.

The downstream part of the dam also rests on thedownstream cofferdam, partially incorporating it. Fig. 5shows the cross section of the right channel dam and thecofferdams during the second phase of the river diver-sion.

3.4 Complementary powerhouseA main concrete gravity dam with an integrated intakestructures, see Fig. 6 Photos (c) and (d), houses the sixhorizontal Kaplan bulb turbine units, and an assemblybay and an un loading bay. The units each have acapacity of 38.85 MW. On the right side there is adividing wall, where the drainage wells are located,connecting the powerhouse to the spillway.

3.5 SpillwayThe spillway is located on the right side of the com-plementary powerhouse, to discharge 62 000 m3/s,with the reservoir at el. 97.5 m (full supply level).There are 18 spans, each 20 m wide and 22 m high,and an ogee crest at el. 76 m (see Fig. 7).


(b) The first phaseof the diversion ofthe Xingu river forthe construction ofall concretestructures at thePimental dam.

Fig. 4. Cross sectionof the left lateraldam.

Fig. 5. Cross sectionof the right channeldam and cofferdam.

There are stoplogs for maintenance upstream anddownstream. The energy dissipation of the dischargedflow is achieved by a stilling basin 50.31 m long. Thespillway has two service bridges, one upstream withthe crest at el. 98 m and another downstream with thecrest at l.98 m.

3.6 Fish transposition systemThe fish transposition channel, see Fig. 8 and Photo(d), is designed for a flow of 12 m3/s to 40 m3/s, it islocated on the left of the complementary powerhouse.It comprises a bypass channel designed to simulate thenatural flow conditions in the river. The entrance struc-ture for the fish is located next to the tailrace channeland has a control structure for a mitre gate for fishattraction. The outlet structure is adjacent to the dam,away from the intake, with a structure for flow controland fish monitoring. That structure has a 1.41 per centslight inclination at the bottom of the channel and 1.2km-long concrete channel composed of a series oftanks separated by transverse deflectors built ingabions, spaced at 14.2 m, which have an opening forthe passage of the flow and fish (gap/vertical groove).The channel has a trapezoidal section of 6 m at thebase and walls with the slope of 1.8 H:1.0 V. The pas-sages provide a 0.2 m difference in level between twosuccessive tanks.

3.7 Boat transposition system The boat transposition system is on the right bank ofthe Xingu river (see Fig. 9). The system consists ofthree semi-channels excavated to approach the boats.On the structures of the semi-canals piers were con-structed for the operation with a travel lift for boats upto 35 t, and an access ramp for small boats. At the pierlevel, there is a platform for the manoeuvering andpositioning of a special self-propelled truck known asthe transporter. The system allows boats to cross thedam from upstream to downstream and vice-versa.There are the following facilities: passenger station;operational control station; parking; workshop; ware-house and gas station; fire System; reservoir; and,water treatment plant.

4. Power canalThe power canal connects the upstream reservoir at thePimental site to the intermediate reservoir, which feedsthe main powerhouse at the Belo Monte site. It is a 20km-long rock-lined conveyance canal with a width of360 m at the top and a minimum width of 210 m at itsbase, and comprises a sequence of straight and curvedstretches, over the entire course of the channel, seeFig. 10 and Photo (e). The canal lined with rock alongthe bottom floor and side slopes in soils with differentgradations. At the entrance to the canal, the bottom isat el. 87 m and it is 500 m wide, maintaining this sizefor a length of 160 m. After that there is a 270 m-longramp down to el. 75 m, where it widens again to 210 m and is maintained at this width. The headracecanal is 25 m deep and experiences flow depths of upto 22.5 m and it was designed to convey a maximumdischarge of 13 950 m3/s, with an estimated averageflow velocity of about 2.5 m/s, for a peak generation of11 000 MW at the Belo Monte powerplant, see Photo(e). The initial impounding of the canal and intermedi-ate reservoir was carried out by a spillway locatedabout 1 km from the entrance of the canal to provide


Fig. 6. Intake and powerhouse.

(d) Pimental site viewed from the downstream side.

Fig. 7. Spillway with 18 gates and a flow capacity of 62 000 m3/s.

(c) Complementarypowerhouse with sixbulb generators andspillway viewed fromthe upstream side.

controlled flows with two gates and a capacity of up to1000 m3/s. An earth cofferdam was also constructed atthe entrance to protect the excavation works of thecanal. The cofferdam was removed at the entrance ofthe canal when the water level inside the canal wasapproximately the same as the water level of the reser-voir at Pimental. A bridge located 13.5 km from theentrance of the canal links both sides of the accessroads.

On both sides of the bottom floor, there are drainagechannels used during the construction phase. The bot-tom rock floor lined with processed rock materialcalled 5D’, with a thickness of 0.6 m, provides uni-formity of the canal’s roughness. In the sectionswhere the bottom floor of the channel is soil, a transi-tion layer 0.2 m thick was laid under the rock linematerial.

The side slopes excavated in soil have a slope of2.5 H:1 V to allow the transit of equipment (tractors)along the slope itself for the application of the rock-fill lining and the slopes excavated in rock haveslopes of 0.5 H:1 V without lining. Both sides of thechannel have access roads at el. 100 m, which delim-its the edge of the channel at a distance of 179.5 mfrom the axis. At els. 84 m and 93 m, the slopes haveintermediate berms, which for a soil excavation con-figuration (see Fig. 11), are 6 m wide. The arrange-ment of section excavated in soil (or conformed byearthfill) constitutes the typical section where thetop of the rock is above the bottom floor of the chan-nel (see Fig. 11). The slopes are excavated with aninclination of 2.5 H: 1 V with the width of the rock-carved shoulders widened to maintain the excavationof the typical section in soil.

As can be seen, soil or earthfill embankments arelined with a 0.6 m-thick 5D rockfill material appliedover a transition layer, 0.2 m in thickness. This 5Dmaterial has a grain size greater than the 5D’ material(applied to the bottom floor); it was obtained directlyfrom the mandatory excavations of the channel.

4.1 Highlights of the power canal constructionThe following are highlights relating to the con-struction of the power canal:• The construction of the power canal was the mostcomplex and difficult component of the project,requiring a major effort on the part of the designer,contractor and the owner to define the hydraulicstudies and logistical plan for the work to be carriedout.• The volumes of excavation required for thecanal were impressive: around 108 ¥ 106 m3 of soiland rock excavation, some of which was below thewater table. Therefore the construction planningrequired a rigorous detailing to ensure satisfactoryexecution. At the peak of construction, the powercanal required around 7000 workers.• For the construction of the power canal it was nec-essary to implement drainage systems to divertcreeks and control the flow of water. Some dykes hasto contain flood waters emanating from the sub-basins, with the effluent flow being reduced by thepond’s routing effect. The drainage of the excessflows from the pond region was done through gal-leries and collection channels.• The geometry and lining of the canal, which affect itshydraulic performance, required studies of optimization,


Fig. 8. Fish transposition system with its strucutures.

Fig. 9. Boat transposition system on the right bank from upstream to downstream ofthe dam and vice-versa.

(e) Power canalwith its dimensions.

Fig. 10. Powercanal arrangement.

which involved a combined evaluation of hydraulic headlosses and efficiency of the generating equipment.• Physical hydraulic model studies were carried outat the LACTEC/CEHPAR laboratory in Curitiba, toassist with the design to evaluate the stability of thelinings and the flow behaviour and velocities.

• Three-dimensional computational modelling ofthe canal was undertaken by the designer, withcollaboration from the team at Ven Te ChowHydrosystems Laboratory, University of Illinois,USA, led by Prof Marcelo Garcia;• Consulting services of the board of consultants ofNorte Energia SA, led by Prof Nelson de SouzaPinto were of great value to the success of the proj-ect.• The designer Intertechne and the civil contractorCCBM with their teams faced and achieved the chal-lenges posed by the owner, Norte Energia SA.

5. Intermediate reservoirThe intermediate reservoir is an artificial lake, formedby 28 dykes and dams of earthfill and rockfill. It hasseven channels for the transposition of basins, andthree channels for reservoir filling, with a total surfaceof 119 km2 (see Fig. 12).

Some of the dykes are actually large dams, including:dyke 8A, see Photo (g), which is 1030 m long, 68 mhigh and has a volume of 5.27 ¥ 106 m3, as well asdyke 13 which is 1987 long, 53 m high and has a vol-ume of 5.75 ¥ 106 m3, see Photo (h). It connects themain reservoir of the Xingu river at the Pimental site,through the power canal, to the main powerhouse,which has an installed capacity of 11 000 MW from 18Francis turbines.

5.1 Filling of the intermediate reservoirThe reservoir impounding process was carried out bya spillway with total capacity of 1000 m3/s controlledby two radial gates, located in the right side of thepower canal, interconnected to the main reservoir, seeFig. 13 and Photo (i).

Sixteen impounding stages were established, whichwere defined so that the process of transposition of theflow between the various basins did not compromisethe integrity of the linings of the transposition chan-nels and the power canal. For this purpose, filling flowrestrictions were established, so as to achieve, in acontrolled manner, the water levels, accumulated vol-umes in the valleys, as well as partial and total timesfor filling.

The initial stage was carried out by the gradual open-ing of the filling spillway, with control of the gatesuntil the flow was 100 m3/s. This flow was maintaineduntil the water level within the power canal, which hasits base at el. 75 m, had reached el. 76 m.

Afterwards, the spillway gates were opened to dis-charge a flow of 200 m3/s, maintaining this flow untilthe water level reached el. 71 m between thePaquiçamba and Aturiá valleys, thus fulfilling steps 2to 11 (see Fig. 13).

With the bottom of the valleys filled with water up to el.71 m, it was possible to increase the water flow throughthe spillway to 500 m3/s and later to 1000 m3/s, thusreducing the total filling time and concluding the process.The total filling of the power canal and intermediatereservoir were successfully ahieved within a period ofabout 45 days.

The removal of the upstream cofferdam of theentrance of the power canal only began when therewas a maximum difference of 0.4 m between thePimental reservoir and the water level inside the powercanal, to avoid erosion in the rock lining of both slopedsides.


(g) Dyke 6C, which is 1.5 km long with a volume of 4.13 ¥ 106m3, and dyke 8A.

Fig. 11. Crosssection of the powercanal in soil androck.

(f) Power canalfilling up afterreservoir impoundingand a bridge viewedcrossing the canal.

Fig. 12.Arrangement of theintermediatereservoir.

6. Belo Monte siteThe Belo Monte site consists of a powerplant with aninstalled capacity of 11 000 MW, with 18 Francis tur-bines, each rated at 611.1 MW, with two large closuredams. The net head is 87 m, from the intermediatereservoir to the tailrace channel, where the waters ofthe Xingu river finally return to the natural river bedafter the diversion, since folowing through the mainreservoir at Pimental. The concept of the designallowed the construction of this huge project to be exe-cuted almost completely independently from thecourse of the river, with no need for river diversionwhile the main structures were being built, keeping theXingu river virtually unaltered during construction.

6.1 General arrangementThe general arrangement of the structures located at theBelo Monte site comprises the generation circuit itself,the intake, the penstocks, the powerhouse and the tail-race channel, two closure lateral earth- and rockfilldams and the Santo Antônio earthfill dam (see Fig. 14).

The power intake structure directs the water collect-ed from the intermediate reservoir to the main power-house through 18 penstocks, each 11.6 m in diameter.

The concrete structures of the Belo Monte site com-prise 18 blocks of the power intake, a concrete-gravitycentral block, two side closure; these are flanked bytwo left and right closure rockfill and earthfillembankments extending to the abutments. The totallength of the power intake and side walls is 819 m withthe crest at el. 100 m.

The concretes used were conventional vibrated con-crete (CCV) and roller compacted concrete (RCC) inthe power intake, central wall and the lateral walls,from the foundation to 1.6 m below the sill of thepower intake (see Fig. 15).

The gravity power intake consists of 18 blocks, each33 m wide. These blocks are in two groups; ten are onthe right and the other eight are on the left, Photo (j). Aconcrete gravity block separates these two groups. Themain powerhouse of the Belo Monte powerplant hous-es 18 vertical axis Francis turbines. The blocks for thegenerating units are 33 m wide, eight of them located onthe left side and ten on the right side, separated by a 33m-wide central block.

There are five blocks on the assembly bay in the leftbank, each 33 m, and two more blocks on the unload-ing bay, 20.7 m wide on the right bank and 36.5 mwide on the left bank.

The excavation for the tailrace channel was in soil androck, about 2 km long and 620 m wide. The left dam clo-sure has a crest at el. 100 m, a maximum height of 88 mand a length of 1100 m, with a volume of 7.79 ¥ 106 m3.The right dam closure has the crest at el. 100 m, maxi-mum height of 54 m and extension of 790 m, with a vol-ume of materials of 1.3 ¥ 106 m3. The Santo Antonio damis located to the left of the power intake in a positionclose to the left dam closure. The dam crest is at el. 100m with the lowest elevation of the foundation beinglocated at approximately el. 30 m, which results in astructure with a height of 70 m. The crest has a width of7 m and an extension of around 1310 m, and a total vol-ume of 6.22 ¥ 106 m3 of earth-fill.

7. Substation and transmission linesThe substation that connects the powerplant to thetransmission line is an insulated SF6 gas, at 500 kV


(h) Dyke 13 in the intermediate reservoir, 53 m high and with a volume of 5.75 ¥ 106 m3.

Fig. 15. Cross section of the intake and powerhouse at the Belo Monte site.

Fig. 14. Arrangement of the main structures at the Belo Monte site.

(i) Spillway for filling power canal; and, intermediate reservoir with upstream cofferdam.

Fig. 13. 16 steps for impounding of the power canal and intermediate reservoir in 45 days.

located upstream of the transformers on the main deckof the powerhouse. The 500 kV transmission linesreach the Xingu substation 16 km away, where theyare connected with the National System Grid (880 kVin direct current).

8. Main data and features of the projectThe main data and features of the project either fore-cast or implemented up to November 2018 are shownin Table 1, and other characteristics of the project areshown in Tables 2 and 3.

8.1 The main events and challengesThe following is a timeline of the main events:• 2011: The beginning of construction. • 2012: Among the challenges faced during the con-struction of the Belo Monte hydropower plant, the firstaccess to intercept the Xingu river at the Pimental site


Table 1: Main features of the project forecast or implemented up to November 2018

Description Predicted volume (m3)

Volume executed (m3) Percentage

Earth and rockfill 69 433 177 69 433 177 100RCC 689 009 689 009 100CVC 2 397 522 2 315 582 96.6Lining of the bottom floor 3 985 712 3 985 712 100

Lining of side slopes 2 373 580 2 375 580 100

Common excavation 121 863 271 121 485 240 100

Rock excavation 44 540 659 44 540 659 100

(j) View fromdowstream of theBelo Monte powerhouse with 12generating units inoperation inDecember 2018.

(k) Belo Montepowerhouse:overview of theremainjnggenerating unitsfrom 13 to 18, inNovember 2018.

Table 2: Main features of the projectPimental

River XinguInstalled capacity 233.1 MWFirm energy 152.1 MWFlooded area 359 km2

QuantitiesCommon excavation 4 269 205 m3

Rock excavation 1 946 811 m3

Earthfill and rockfill 11 676.030 m3

Concrete 666 687 m3

Power intakeType GravityTotal length 114.3 mGatesType StoplogsWidth 5.64 mHeight 17.33 mComplementary powerhouseType SurfaceGenerator units 6Width of blocks 67.15 mTotal length 114.3TurbinesType BulbNominal power 38.85 MWRotation speed 100 rpmNominal head 11.4 mNominal rated flow 392 m3/sMaxium efficiency 94.5 per centGeneratorsNominal power 40.9 MVARotation speed 100 rpmNominal tension 13.8 kVMinimum yield 97 per centPower factor 0.95Total weight per unit 2700 kNSpillwayType Low headMaximum flow 62 000 m3/sSill elevation 76 mTotal length 445.5 mNumber of spans 18Width 20 mGatesType SegmentWidth 20 mHeight 22 mRight channel damType Earth-rockfillTotal length 834 mHeight 40 mWidth of crest 9 mCrest elevation 100 mLateral left damType EarthfillTotal crest length 5100 mHeight 14/23 mCrest elevation 100 mPower canalMinimum width of the bottom 210 mTotal length excavated 20 181 mTotal length after impounding 16 200 mMaximum flow depth 22.5 mMaximum flow 13 950 m3/sCommon excavation 86 957 163 m3


Bottom lined with rock 2 704 765 m3

Embankment 8 942 544 m3

Concrete 38.152 m3

was one of them. The beginning of the installation ofthe site facilities such as: lodging for workers; cater-ing; quarry; rock crushing system; batch plant; iceplant; and, industrial yards for concrete, formwork andsteel reinforcement were all part of the initial stages.The beginning of the preparatory works for the firstphase of the works to divert the Xingu river, as well asthe beginning of the excavation of the power canal,the excavation of the intake and powerhouse of theBelo Monte site also took place in 2012.• 2013: In January 2013, the major targets were thecompletion of the works of the first phase of the Xinguriver diversion, and the beginning of the operation ofthe boat transposition system. Among the goalsachieved in 2013, were the beginning of the concreteplacement of the Pimental powerhouse in February, aswell as the beginning of the concrete placement of theintake and powerhouse at Belo Monte.• 2014: The electromechanical assembly becameimportant in June 2014 with the start of the operationof the main crane at the Belo Monte site, when thestayring of generating unit 1 (UG 1) of the powerhousewas put in place. The installation of the floodgates atthe Pimental site began in July 2014. By November2014, excavations had already exceeded 160 ¥ 106 m3,as well as 40 ¥ 106 m3 of earthfill and more than 2 ¥106 m3 of concrete. At the end of that year, the BeloMonte hydro plant had reached the peak of construc-tion, with more than 37 000 workers on site and greatadvances in construction.• 2015: Two events of great significance wereachieved in 2015 at the Pimental site: the second phaseof diversion of the Xingu river by the spillway in Julyand, in August the closure of the right channel of theriver with the second stage cofferdams, allowing forthe beginning of the filling of the reservoir inNovember. At the beginning of the second phase diver-sion, on 31 July, the first phase cofferdams were


Intermediate reservoirDam 3Dykes 28Transposition channels 7Filling channels 3Flooded area 119 km2

Common excavation 21 508 433 m3

Rock excavation 690 141 m3

Bottom lined with rock 1 005 925 m3


Concrete 44 272 m3

Belo Monte siteRiver XinguInstalled capacity 11 000 MWFirm energy 4419 MWQuantitiesCommon excavation 25 899 698 m3



Concrete 2 305 612 m3

Power intakeType GravityTotal length 627 mGates (emergency)Type WagonWidth 10.1 mHeight 15.68 mPenstockInternal diameter 11.6 mNumber of units 18Average length 115.13 mMain powerhouseType ShelteredNumber of generating units 18Width of unit blocks 33 mWidth of central block 33 mTotal length 849.2 mTurbinesType FrancisNominal unit power 611.11 MWSynchronous rotation 85.71 rpmNominal net head 87 mNominal rated flow 775 m3/sWeighted average yield 95.63 per centTotal weight per unit 21.182 kNGeneratorsNominal unit power 679 MVASynchronous rotation 90 rpmRated voltage 18 kVMaximum yield 98.65 per centPower factor 0.9Total weight per unit 25.740 kNRight closure damType Earth/rockfillMaterial Soil/rockTotal crest length 790 mMaximum height 55 mElevation crest 100 mLeft closure damType Earth/rockfillMaterial Soil/rockTotal crest length 1085 mMaximum height 88 mCrest elevation 100 m

Table 3: Targets achieved for power generation to 2018

Start of commercial operation

Pimental site (Bulb =

38.8 MW)

Belo Monte site (Francis =

611.1 MW)Totalunits

April 2016 UG-01 UG 01 2June 2016 UG-02 - 1July 2016 - UG 02 1August 2016 UG-03 - 1November 2016 UG-04 UG 03 2December 2016 UG-05 1Total 2016 5 3 8January 2017 UG- 06 UG 04 2April 2017 - UG-5 1July 2017 - UG 6 1October 2017 - UG-7 1Total 2017 1 4 5February 2018 - UG-8 1June 2018 - UG-09 1October 2018 - UG-10 1November 2018 - UG-11 1December 2018 - UG-12 1Total 2018 - 5 5Grand Total 6 12 18

removed, and the right channel was closed on 7August. The uncertainties surrounding the foundationconditions in the right channel led the designers todevelop the upstream cofferdam, with the purpose ofretaining the reservoir for one year until the final con-struction of the right channel dam. The building of anupstream cofferdam capable of functioning temporari-ly as the main dam of the Xingu river, with 1.2 ¥ 106 m3

of material in 80 days, and at 40 m high, was a greatchallenge for all involved in the construction of theBelo Monte hydro plant. After the completion of all thestructures, the filling of the main reservoir at Pimentalbegan on 24 November, and, on 12 December the fill-ing of the power canal and intermediate reservoir beganthrough a spillway with two gates located on the rightbank at the beginning of the canal.• 2016: The completion of the filling of the reservoirsoccurred on 15 February 2016, as shown in Fig. 12. InOctober 2016, the right channel dam at Pimental wascompleted. Since the beginning of impounding of thereservoirs in November and December 2015, theupstream cofferdam in the right channel had playedthe role of the right channel dam.• 2017: Secondary concrete placement took place andcommercial operation began of the last bulb turbine atPimental and four Francis turbines at Belo Monte.• 2018: Secondary concrete placement took place andcommercial operation began of five Francis turbines inBelo Monte.8.2 Construction methodologyThe most relevant construction methods employed inthe concrete structures at the Belo Monte site were theRCC at the intake, using the sloped layer method ofplacement.

As well the construction method with pre-assembledsteel bars, the use of slipforming with pumped con-

crete in the concrete structures of the intake, power-house and spillway sped up the construction at BeloMonte and Pimental.8.3 Peaks of outputSeveral world records of common and rock excava-tion, as well as earthfill and rockfill services have beenachieved:• Peak of monthly output of structural concrete: 110 000 m³ in September 2014.• Peak of monthly output of common excavation: 6.6¥ 106 m³ in July 2015.• Peak of monthly rock excavation: 2.5 ¥ 106 m³ inJuly 2015.• Peak of monthly output earthfill and rockfill: 6.28 ¥106 m³ in July 2015.• Peak of the workers in civil contracting in 2014: 37 000 workers.• Peak of the equipment for civil contracting in 2014:3800.9. ConclusionsCompletion of the Belo Monte project will be an impor-tant milestone for Brazil, as it allows for the continuityof electrical supply to meet increasing demand on thenational grid. Conclusion of this huge project will alsoprovide for substantial additional generation at relative-ly low cost without a negative environmental impact. ◊The main organizations involved in the project• Civil contractor (consortium CCBM): AndradeGutierrez (Leadership), Camargo Correa, NorbertoOdebrecht, OAS, Queiroz Galvao, Galvão Engenharia,Contern Cetenco, Serveng and J. Malucelli. • Civil Designer (consortium IEP): IntertechneConsultores SA (Leadership), Engevix SA and PCE.• Electromechanical assembly: ConsortiumCOMGEV ENESA (Leadership), GE and Voith (BeloMonte) and Andritz (Pimental).• Manufacturers: Andritz, Impsa, Voith and GE.• Panel of experts for civil works: Nelson de SousaPinto (Chairman and Hydraulics); Joaquim Pimenta deAvila and Paulo Teixeira da Cruz (Geotechnical);Sergio Brito (in memoriam) and Ricardo Abrahão(Geology); and, Walton Pacelli de Andrade andFrancisco Rodrigues Andriollo (Concrete).• Intrumentation: SBB Engineering - Joao Franciscoda Silveira.AcknowledgementThe authors would like to thank Norte Energia personnel for theirdedication in building this huge project in the middle of theAmazon jungle and in particular, are grateful to the Board ofDirectors of Norte Energia, who since 2011 have contributedmuch to the construction of the project. Special thanks go to all ofthe current Board of Directors and their staff, for their support andincentive to raise the standards of challenges and achievements.


Table 4: Features of the Francis turbine at Belo Monte

Equipment Diameter (m) Weight (t)Penstock 11.6 1310Turbine runner 8.5 317Generator rotor 18 1300Generator stator 22 700

Table 5: Features of the horizontal Kaplan-bulb turbine at Pimental

Equipment Diameter (m) Weight (t)Generator rotor 8.45 100Generator stator 9.1 102Distributor 9.1 81Kaplan rotor 7.14 61Draft tube 10.7 to 8.1 48

(l) RCC sloped layer carried out at the power intake

(m) Slipformingapplied at thespillway and powerintake.

BibliographyMenezes, J.B., Bandeira, O.M., and Leite, D.T., “A construção

do complexo hidrelétrico de Belo Monte quarta maior domundo em capaciade instalada” (in Portuguese), CBDB -Revista Brasileira de Barragens (Journal of the BrazilianCommittee on Dams); May 2017.

Bandeira, O.M., “The 11 233.1 MW Belo Monte HydropowerComplex with its challenges and achievements”, III DamWorld Conference, IBRACON/LNEC, Brazil; 2018.

Reynaud, F., Araujo Filho, M.F., Grube, R., Piovesan, R.,and Kamel, K.F.S.,“The power canal at Belo Monte: Arecord-breaking feature of the scheme”, Hydropower & DamsNo. 3, 2017.

CCBM, Monthly progress reports, Consortium Civil ContractorBelo Monte, 2017/2018.

Bandeira, O.M., Leite, D.T., Boaventura, M.B., Foz, Valino,L.S., and Sarlo, R.J.F., “Main challenges of the diversionchannel of the Belo Monte HPP”, III Dam World Conference,IBRACON/LNEC, Foz do Iguaçu, Brazil; 2018.

Lopes, A., Silva Liberio, A. and Ferreira, A.M., “UHE-BeloMonte-Sitio Pimental: O desvio do Rio Xingu”, (inPortuguese), CBDB - Revista Brasileira de Barragens(Journal of the Brazilian Committee on Dams); 2017.


Oscar Machado Bandeira graduated as Civil Engineer fromthe University Federal of Paraiba in Campina Grande,Brazil. He has a postgraduate degree in Audit, Assessmentand Forensic Engineering 2016/2017 by IPOG- Brazil. From1969 to 1975, he worked in construction of highways,railways and bridges. From 1976 to 2018, he has beeninvolved in several hydropower construction projects inBrazil and worldwide including: Itaparica, Xingo and,Tucurui (Brazil); TSQ-1 (China); Bakun (Malaysia); and,Siah Bishe (Iran). Since 2011 he has been involved in thebasic, detailed design and construction of Belo Monte withthe developer Norte Energia SA. He is currently theSuperintendent of Engineering and Construction of BeloMonte Dam in the Owner Norte Energia

José Biagioni de Menezes graduated in Civil Engineeringfrom the Kennedy Engineering School of Minas Gerais,Brazil, in 1978. Until 1979, he was involved with theconstruction of 80 m-high Salto Santiago dam. Then, up to1982 he worked on the Itaipu dam with its 14 000MW,hydropower plant. He then joined Eletronorte and worked onthe construction of the Balbina and Tucurui dams. He wasGeneral Manager of the Tucurui Extension Project,responsible for the management, supervision and qualitycontrol of the civil and eletromechanical works. Since 2011he has been involved with Belo Monte project as ContractSuperintendent working for the owner, Norte Energia S.A.Norte Energia SA, Ed. Centro Empresarial Varig SCN- Quadra 04- Bloco B, 100 Salas: 904, 1001 CEP:70714-900- Brasilia/ DF, Brazil.

O.M. Bandeira J.B. de Menezes

current progress at the belo monte hydro project, …...of the first turbines during the time...

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