DAMS & HYDROPOWER

ENGINEERING PROFILE

ARQ DAMS (PTY) LTD DAMS EXPERIENCE

MILESTONE INTERNATIONAL RCC PROJECT AWARD

ARQ’s Changuinola 1 Dam in Panama was awarded “Milestone International RCC Project”, an award that is supported by ICOLD and recognises the dam as being one of the 15 to date to have contributed most significantly to the development of RCC technology. As the first RCC arch dam outside South Africa and China, the design of Changuinola 1 Dam was based on ARQ’s research that recognises the different stress-relaxation creep behaviour of different RCC types.

DAMS EXPERIENCE

ARQ has been active in dam engineering since 1993 and this field now represents one of the firms’s primary areas of activity. ARQ has been involved in over 80 projects involving dams, hydropower and river engineering in 26 countries; with 36 new dams completed, or currently under construction (the highest being 275 m), 13 completed projects involving major rehabilitation or raising, 24 projects at pre-feasibility and feasibility level (highest dam of 281 m) and 14 dam safety / asset evaluation studies. ARQ has contributed staff as specialists on international projects involving design precedents and as members of expert panels.

Completed dam types include RCC, rubble masonry concrete, concrete, CFRD and earthfill.

Roller Compacted Concrete (RCC) and arch dams represent the key areas of specialisation for ARQ and the majority of the company’s large dams activities are focussed on RCC. In RCC dams, ARQ has provided services including planning, design, thermal analysis, structural and dynamic analysis, specification preparation, construction advice and assistance, construction method development, construction supervision, mix design development and safety inspections.

Wadi Dayqah Dam (Oman – 75 m, June 2010)

Ayvali Dam (Turkey - 178 m, March 2015)

Changuinola 1 Dam (Panama - 105 m arch, June 2011)

UNDER CONSTRUCTION & COMPLETED RCC DAMS IN WHICH ARQ HAS HAD A PRIMARY INVOLVEMENT INCLUDE:

Dam Country Height (m) RCC Volume (m3)

Köroğlu Turkey 95 560 000

Kotanli Turkey 85 235 000

Ayvali Turkey 178 1 660 000

Changuinola 1 Panama 105 895 000

Neckartal Namibia 85 920 000

Çine Turkey 136.5 1 650 000

Wadi Dayqah Oman 75 550 000

Ambarau DRC 22 30 000

Bramhoek RSA 38 90 000

Umti Oman 23 35 000

ARQ provided expertise on the External Review Panel for the De Hoop (85 m in height + 1,125 million m3 RCC) and Spring Grove dams (42 m & 90 000 m3 RCC) in South Africa and for the Owner’s Engineer on Trung Son (84 m & 750 000 m3) in Vietnam. The total quantity of RCC placed in which ARQ and its personnel has had a direct involvement exceeds 7 million m3. Furthermore, ARQ has experience in a range of RCC dam types and construction technologies, from Hardfill to the current state of the art super-retarded, high workability RCC. The Changuinola 1 Dam, (230 MW hydropower project) completed in 2011 in Panama, was the first RCC arch/gravity dam outside China and South Africa where ARQ was the EPC contractor’s designer for the dam. ARQ was also responsible for the preparation of the South African RCC specification and has been acknowledged by the SA Department of Water Affairs as “.. the recognized experts in the field of Roller Compacted Concrete (RCC) dams in the private sector in South Africa.

ARQ has significant implementation experience in various of the recent technological developments in RCC construction. The company has also extensive experience in specialist areas of RCC design, such as thermal analysis, earthquake design analysis and RCC mix design. The RCC at Wadi Dayqah Dam in Oman

Seamless GERCC RCC Joint (Wadi Dayqah) Çine Dam (Turkey – 136. 5 m, Feb 2012)

very successfully used crushed limestone to augment the sand and improve particle mobility and milled limestone as a paste replacement filler.

ARQ are the arch dam designers in a JV with Su Yapi for the 275 m Yusufeli double curvature concrete arch dam in north-eastern Turkey. ARQ is responsible for the structural arch design, all structural, thermal and dynamic analyses, the design of all works related to the dam structure and the development of foundation rock mass improvement measures in cooperation with IC of Austria. ARQ is further providing assistance and advice to the contractor (LCK Joint Venture) on construction issues, such as plant, post-cooling, methods, etc, and assistance to the owner, DSI, on the spillway design and model testing and the concrete mix designs.

Trung Son, Vietnam September

Kotanli Dam, Turkey September

Neckartal Dam - January 2017

Çine Dam RCC

Köroğlu Dam - January 2017

Yusufeli Dam – Artvin, Turkey

FE Analysis: Changuinola 1 RCC Arch/Gravity Dam

OTHER SIGNIFICANT RCC & CVC DAM PROJECTS OF INTEREST ARE LISTED BELOW: Dam Height (m) RCC/CVC Volume (m3) Status

Yusufeli, Turkey (Double curvature CVC arch) 275 3,8 million (CVC) Under construction

Ratle, India 133 1,25 million Project suspended

Stieglers Gorge, Tanzania (Arch) 130 1,1 million Feasibility

Nam Theun 1, Laos (Arch/gravity 180 2,4 million EPC design

Wolwedans (Arch/gravity) 70 220 000 Completed 1990

Basha Diamer, Pakistan 281 10 million Feasibility

Sounda, Rep. Congo (Arch) 132 700 000 Tender design

Baynes, Nambia/Angola (Arch/gravity) 220 2,8 million Feasibility

Jana 186 2,9 million Feasibility

Mielietuin (Arch) 100 660 000 Feasibility

Specialist-level analyses completed for major RCC dams include a full time-history dynamic seismic analysis for Changuinola 1 Dam (105 m – pga = 0.4g) and thermal studies for Çine Dam (136.5 m).

Ambarau Hardfill Dam - DRC

Time History Dynamic Analyses for Changuinola 1 Dam

Thermal Study for Çine RCC Dam

Thermal Study for De-Hoop RCC Dam

Çine Dam, Turkey

ARQ HAS UNIQUE EXPERIENCE IN RCC ARCH DAM DESIGN AND CONSTRUCTION.

Finite Element modelling for Stieglers Gorge Dam

FE modelling for Changuinola 1 Dam

FE model & modelling for Nam Theun 1 Dam

Kotanli Dam

Changuinola 1

Changuinola 1

Whilst RCC, concrete and arch dams are ARQ’s particular specialization, the company has been involved in the design, construction supervision and safety evaluation of a number of embankment dams, including several earthfill and rockfill dams. THE FOLLOWING TABLE LIST ARQ’S PRIMARY INVOLVEMENT IN DAM ENGINEERING

Scheme/ Dam

Project Value Dam Height/ Type ARQ Involvement No. of Staff Months

Yusufeli Dam, Turkey

TL 900 million 275 m CVC double-curvature arch

Arch Dam specialists/designers for EPC contractor in design and construction. Dam design & major construction plant specification.

60 to date - ongoing

Nwamitwa Dam

R 2.3 billion 40 m composite RCC/ earth & rockfill

Dam designers & geotechnical investigations for Tender design.

135 to date

Tzaneen raising

R 430 million 56 m composite conc./earth fill

Dam design and construction supervision assistance.

40 to date

Ratle Dam, India

US$ 1,4 billion 133 m RCC gravity Dam design team leaders for EPC contractor in design & construction.

81

Wadi Umti Dam, Oman

US$ 10.8 million 23 m Hardfill Advisors and technical specialists to contractor for tender and construction.

4

Kotanli Dam, Turkey

US$ 75 million 85 m RCC/ Arch/Gravity

RCC dam design & RCC specialists for design & construction.

40

Köroğlu Dam & HEPP, Turkey

US$ 115 million 100 m Arch/Gravity RCC dam

RCC dam design & RCC specialists for design & construction

45

Ntsonyeni Dam

R 300 million 35 m Hardfill Tender design & construction supervision assistance.

15

Neckartal Dam, Namibia

US$ 170 million 85 m RCC Gravity RCC specialists. 3 to date -ongoing

Trung Son Dam & HEPP, Vietnam

US$ 700 million 84 m RCC Gravity Owner’s Engineer RCC Specialist. 2.5

Changuinola 1 Dam, Panama

US$ 450 million 105 m RCC Arch Dam designers. 255

Ambarau, Democratic Republic of Congo

US$ 65 million 22 m Hardfill Construction design + supervision assistance.

28

Çine Dam, Turkey

US$ 1.1 billion 136.5 m RCC Gravity RCC dam design, RCC specialists for design & construction. Thermal analyses, etc

25

Wadi Dayqah Dam, Oman

US$ 110 million 75 m RCC Dam structural design & RCC specialists for design & construction.

4

Bramhoek Dam & Bedford Dam

R 850 million

38 m RCC & 49 m CFRD

Team leaders for dam design as part of a large project team for Ingula Pump Storage Scheme. APP for supervision.

82

Stiegler’s Gorge Dam & HEPP

US$ 1.8 billion 130 m RCC Arch Engineering feasibility study & design. 20

Scheme/ Dam Project Value Dam Height/ Type ARQ Involvement No. of Staff Months

DWAF Group 1 dams rehabilitation

R 400 million 15 – 30 m Earthfill – 9 dams

Chief engineers for design & construction supervision of various dam betterments.

160

Ayvali Dam, Turkey

US$ 250 million

178 m RCC Arch Feasibility design, FE specialist analyses and RCC specialists for design & construction.

15

De Hoop Dam R 2.5 billion 85 m RCC Gravity Member of external review panel for design & construction.

16

Berg River Dam

R 917,3 million 70 m CFRD Member of external review panel for design & construction.

6

Nam Theun 1 Dam (& HEPP), Laos

US$ 600 million

177 m RCC Arch Basic & EPC design of RCC dam. 15

Mukurumudzi Dam

US$ 21 million 23 m high Earthfill dam

Design tasks: detailed design, drawings, tender documentation including specifications. Specialist Assistance on construction supervision.

14

Kembe HEPP, C.A.R.

US$ 340 million

30 m RCC/Earthfill Feasibility design. 24

Gibe III, Ethiopia

US$ 2 billion 243 m RCC Gravity RCC mix assistance 0.5

Sounda HEPP, Republic of Congo

US$ 1.8 Billion 132 m RCC Arch Feasibility design. 17

Epupa HEPP, Namibia

US$ 500 million

220 m RCC Arch Feasibility design. 8

Basha Diamer, Pakistan

US$ 10 billion 285 m RCC Gravity Structural specialists for feasibility design.

4

Thukela Water Project

R 1.5 billion 185 m RCC & 98 m RCC

Team leaders for dams & preliminary design for feasibility study.

60

Midmar Dam Raising

R 45 million 32 m Conc/ Earthfill Conceptual, detailed design & supervision assistance for 3.5m raising.

30

Lucilia Poort Dam, Zimbabwe

R 8 million 42 m Masonry Arch External reviewer for dam design & construction supervision.

2

Karacasu Dam, Turkey

US$ 120 million

75 m Gravel Fill Feasibility design of dam embankment. 3

Mndwaka Dam R 52 million 32 m Masonry Detailed design & supervision assistance 24

Arnaud Dam, Mauritius

US$ 10 million 16 m Earthfill Detailed design & supervision assistance 8

Port St Johns Dam

R 22 million 23 m Masonry Arch Detailed design & supervision assistance 10

Arnaud Dam, Mauritius

US$ 10 million 16 m Earthfill Detailed design & supervision assistance 8

Port St Johns Dam

R 22 million 23 m Masonry Arch Detailed design & supervision assistance 10

Scheme/ Dam Project Value Dam Height/ Type ARQ Involvement No. of Staff Months

Port St Johns Dam

R 22 million 23 m Masonry Arch Detailed design & supervision assistance

10

Biri Dam, Zimbabwe

US$ 30 million 44 m Earthfill Tender design & documentation for earthfill dam.

8

Aloe Cove Dam R 8 million 23 m Masonry Design & construction supervision. 15 Bellair Dam R 11 million 21 m Masonry Design, specifications & supervision

assistance. 3

Hoggsback Dam

R 580 000 12 m Masonry Dam design. 3

Welgevonden Dam

R 800 000 17 m Masonry Dam design & supervision assistance. 3

Yusufeli Dam Valley, Turkey, 12 Oct 2016 Yusufeli Dam Finite

Umti Dam, Oman

Molepo Dam: September 2010

Bospoort Dam: October 2009

Wadi Dayqah Dam: June 2009

Bospoort Dam: October 2010

Bramhoek Dam: May 2010 & March 2011

Bedford Dam: May 2010

Bramhoek Dam: July 2011

Köroğlu Dam

Bramhoek Dam: May 2010 & March 2011

Berg River Dam: October 2007

ARQ DAMS (PTY) LTD HYDROPOWER EXPERIENCE

Mount Coffee HEPP (64MW) (Liberia)

Kotanli HEPP (50MW) (Turkey)

Through their expertise in dam engineering ARQ has become increasingly involved in hydropower projects, particularly in central Africa.

Outside Africa, ARQ provided design and supervision services on the 230 MW Changuinola 1 hydropower scheme in Panama and is providing services on the 150 MW Ayvali HEPP, the Kotanli 50 MW HEPP and the Koroglu 80 MW HEPP in north-eastern Turkey. In Laos, ARQ assisted with design on the 150 MW Nam Theun 4 and the 500 MW Nam Theun 1 hydropower schemes. ARQ also assisted with specialist services during construction on the Trung Son 260 MW hydropower project in Vietnam. ARQ recently completed engineering design services for the 850 MW Ratle HPP project in the state of Jammu & Kashmir, India.

ARQ also served on the Panel of Experts for Dam Engineering and Dam Safety for the 64 MW Mount Coffee HEPP Rehabilitation project. On the Braamhoek 1330 MW pumped storage hydropower scheme for Eskom, ARQ fulfilled the role of Team Leaders for dam engineering.

In co-operation with Jeffares & Green Afrika (JG Afrika), ARQ completed a feasibility study for the Kembe HEPP (60 MW) in the Central African Republic, while the

company was also recently responsible for a compre-hensive update of the Stieglers Gorge HEPP 800 MW) in Tanzania.

For the Sounda Hydropower Project in Republic of Congo, ARQ is acting as project managers for the hydropower and dams aspects of a 1000 MW scheme, in co-operation with JG Afrika. While construction for the first phase was halted in 1997, when a coup d’état occurred,

the scheme has recently been revived and proposals envisage the development of a 1000 MW project in a single phase.

Also in Congo, the locally funded Mourala Falls 4 MW hydropower project, designed by ARQ for JG Afrika, was also stopped in 1997, as the earthworks were being initiated. This scheme is also being revived

Q DAMS PTY) LTD HYDROPOWER EXPERIENCE

ARQ was brought in by a Norwegian-Swedish team to assist on the pre-feasibility and feasibility stages of the Epupa Hydropower Project on the Kunene River, forming the border between Namibia and Angola.

ARQ’s work on the later phase focussed on the Baynes Dam, which would not flood the Epupa Falls themselves.

ARQ acted as designer and project manager for the pre-feasibility evaluation of the 50 MW Poubara Falls hydropower scheme in southern Gabon

VARIOUS HYDRO SCHEMES IN AFRICA

ARQ acted as project managers and civil engineers for the rehabilitation of two micro-hydropower schemes on the island of Bioco, Equatorial Guinea. With a team including Trans Africa Projects and Clackson, all mechanical, electrical and transmission components for both plants were replaced and the generation was connected into the local power grid. The refurbished power stations together generate a total of approximately 500 kW, the same power for which the schemes were originally constructed.

The original horizontal axis Francis turbines were replaced by South African made cross-flow units, requiring extensive modifications to the power stations. While quite extensive repairs to the headrace and reject canals were necessary for both stations, the offtake and penstock inlet valves and gate mechanisms did not generally require major refurbish.

Poubara Aval Scheme

Q DAMS PTY) LTD HYDROPOWER EXPERIENCE

Ambarau HEPP (DRC)

ARQ is contracted as part of the World Bank’s Panel of Experts for the rehabilitation and capacity enhancement of the Inga I and II hydropower schemes in the Democratic Republic of Congo. In the same country, ARQ is assisting the Ministry of Electricity and Hydraulic Resources with technical and contractual advice on various hydropower projects currently under construction ARQ is contracted as part of the World Bank’s Panel of Experts for the rehabilitation and capacity enhancement of the Inga I and II hydropower schemes in the Democratic Republic of Congo. In the same country, ARQ is assisting the Ministry of Electricity and Hydraulic Resources with technical and contractual advice on various hydropower projects currently under construction

ARQ provided assistance with civil design and project control on a number of hydropower schemes in Democratic Republic of Congo, including the 20 MW Grand Katende project near Kananga, and the Ambarau HEPP in the north east of the country

ARQ completed a detailed review of a comprehensive feasibility study for the proposed 100 MW Djiploho HEPP on behalf of the Ministry of Mines, Industry & Energy of Equatorial Guinea.

Also in Equatorial Guinea, ARQ successfully project managed extensive repair and refurbishment work on various mechanical, electrical and control equipment at the 4,8 MW Riaba power station

A series of small hydropower schemes on the Lower Orange River, with a view to supply Namibia with 108 MW of power. In Malawi, ARQ provided consulting services for feasibility to Rural Maintenance Ltd on four mini-hydropower projects to be incorporated into a grid system, including solar, wind and thermal power: • 2 MW Hydropower scheme at the Chisanga Falls on the

North Rukuru River;

• 2 MW Hydropower scheme on the Lufira River, some 23 km north west of the town of Karonga;

• 1 MW Hydropower scheme at the Vukuvuku Rapids on the South Rukuru River.

Feasibility studies for seven mini-hydro-power stations in the Western Region of Kenya varying from 4MW to 8MW have been undertaken for a private developer with the goal of implementing the best five stations: Kaptis, Chepkumia, Sirwa, Buchangu, Lugari and Kipkaren.

WWW.ARQ.CO.ZA Physical Address: 6 Daventry Street, Lynnwood Manor, 0081, Pretoria, South Africa

Postal Address: PO Box 76379, Lynnwood Ridge, 0040, Pretoria, South Africa

Office: +27 (12) 348 6668

Fax: +27 (12) 348 6669

Email: arq@arq.co.za