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Serving the hydro industry for over 60 years

Developments in dam engineering

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Developments in dam engineering

Back in serviceVeteran TBM takes on a new challenge

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CONTENTS

Editor Carrieann Stocks Tel: +44 20 8269 7777 carrieannstocks@globaltrademedia.com

Contributing Editors Patrick Reynolds Suzanne PritchardEditorial Assistants Elaine Sneath, Tracey HonneyAdvertising Sales Scott Galvin Tel: +44 20 8269 7820 scottgalvin@globaltrademedia.com

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DAMENGINEERING

ModernPowerSystemsCOMMUNICATING POWER TECHNOLOGY WORLDWIDE

COVER: Learn more about the role a Robbins TBM is playing on a hydro project in the Faroe Islands on p30

36

40

32

24

46 PROFESSIONAL DIRECTORY 48 WORLD MARKETPLACE

R E G U L A R S 4 WORLD NEWS 8 APPOINTMENTS

F E A T U R E S

DAM ENGINEERING 12 The tail end of a story Sharing experiences of tailings dam development

16 Major advance for minimum energy loss culverts Charting the development of MEL culverts

20 Engineering on-the-go New system designed to optimise engineering

22 Influencing engineering The 20 most influential people in dam engineering

TUNNELLING 24 Multiple challenges Challenging tunnelling projects in Latin America and Asia

28 Nearing breakthrough at Niagara An update on work at the North American project

30 Back in service for hydro expansion Veteran TBM gets back to work on the Eidi project

EQUIPMENT 32 Satellite communications Delivering communications at remote dam site

34 High alert from High Sierra Flood warning network plays crucial role

PROJECT UPDATE 36 Developing Dagachhu Details on the bilateral hydro scheme in Bhutan

SMALL HYDRO 38 Creative design work Developing a small hydro scheme in China

FISH PASSAGE 40 Water flow monitoring aids fish passage Helping American Eel pass the St Lawrence dam

RESEARCH 42 Predicting maximum scour depth Arun Goel presents an estimation of maximum scour

depth downstream of ogee spillways

4 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

WORLD NEWS

INTERNATIONAL HYDROPOWER Association (IHA) members have confirmed support for the Associations adoption of the revised Hydropower Sustainability Assessment Protocol, ensuring that the Protocol excels as a sustain-ability assessment tool to measure and guide performance in the hydro-power sector.

IHAs adoption of the Hydropower Sustainability Assessment Protocol follows a two and a half year collabo-rative journey, with representatives from different sectors, resulting in signi!cant review and redrafting of the Associations previous 2006 Protocol.

The Protocol is the product of con-siderable effort by parties represent-ed in the Hydropower Sustainability Assessment Forum. The Forum, assisted by associated reference groups, has been deeply involved in

research, analyses, meetings, out-reach, trialling, review, exchanging views, negotiating content and !nd-ing solutions to divergent views. The revised Protocol reflects a shared vision that it will make a signi!cant contribution to advancing sustain-able hydropower.

The adoption process started in September 2010, with the IHA Board recommending that the Protocol be adopted by the Association, in place of its 2006 version. The IHA Board also set the stage for future devel-opment and improvement of the Protocol by recommending that the Protocol tools should be subject to periodic updating, incorporating the experience gained through ongoing consultation and its application. In accordance with its constitution, IHA issued a Board Resolution in support of adoption to its members and, fol-lowing a consultation period where

there was overwhelming support in favour of adoption, the Protocol is now of!cially adopted.

This adoption also marks the start of a new process of investigating future developments surrounding the Protocol. IHA is once again embark-ing on a cross-sectorial collaborative process, working closely with partners for the next phase of the Protocols ongoing development.

Considerable progress has already been made in the investigation of a governance model for Protocol imple-mentation with a meeting being held between IHA and its partners in November, which resulted in the development of a framework for the incorporation of an interim entity to guide the process. IHA. The fruits of this work will be presented at the next IHA World Congress, which will be held Iguassu, Brazil, during 14-17 June 2011.

Commenting on members sup-port for Protocol adoption, IHA Executive Director, Richard Taylor, said: The call to adopt the revised Protocol resulted in the Associations membership clearly indicating its support for the Protocols role as a sustainability assessment tool to measure and guide performance in the sector.

The 2006 Protocol has under-gone a significant review and redrafting over the past two and a half years, under the guidance of the Hydropower Sustainability Assessment Forum. IHAs Board believes that the tools contained in the Protocol can make a signi!cant contribution to the advancement of sustainable hydropower. We acknowl-edge the considerable work that was undertaken by all the members of the Forum to deliver the revised version, Taylor added.

IHA adopts the Hydropower Sustainability Assessment Protocol

Finance secured for Cheves project, PeruIFC, A MEMBER OF THE WORLD Bank Group, will provide long-term !nancing of up to US$250M to help build the 168MW Cheves hydropower project in Peru, project developer SN Power has announced.

IFC together with DnBNOR, Nordea, West LB and Societe Generale were mandated joint lead arrangers in June 2010. IFC and DnBNORs willingness to provide the very long tenors of 20 years, and the other commercial banks providing 17 years, were essential to allow for the !nancial viability of this investment.

This is a key milestone ensuring the funds for the construction of the project, said Nils Huseby, Executive Vice President South America. The

timely closing of this financing has been the result of good team work both in the SN Power organi-zation and among the !ve lending institutions. SN Powers experience in working with IFC and the good cooperation from the commercial banks makes this a benchmark for future deals.

DnBNOR has supported SN Power in several deals in Chile, and will also participate in the re!nancing of SN Power Peru, which is taking place in parallel to the Cheves !nancing.

Nordea has, in addition to Cheves, been another !nancial key supporter of SN Powers two hydro projects in Chile. West LB and Societe Generale are new investors to SN Power.

Located on the Huaura River, 250km north of Lima, Cheves is one of the very few hydropower projects developed in Peru in the last decade and therefore represents a corner-stone in Perus goal to promote the use of largely untapped renewable energy resources.

SN Power, through the project com-pany Empresa de Generacin Elctrica Cheves SA, will build and operate the plant. Construction starts in January 2011 with completion in 2014.

This project shows our commit-ment to developing renewable-energy resources in Peru and other emerg-ing markets, said Huseby. It also sends a positive signal to developers and !nanciers regarding the invest-

ment opportunities in Perus renew-able-energy sector and availability of long-term !nancing.

Cheves is expected to produce about 836GWh of electricity annu-ally starting in 2014. The increase in energy supply will serve individual households and industrial clients, such as mining projects.

Civil works on the project are being carried out by a Joint Venture between Hochtief Construction AG, Empresa Constructora Tecsa S.A. and ICCGSA Ingenieros Civiles y Contratistas Generales S.A. Other !rms involved in the project include Rainpower, Jeumont Electric, ABB, Abengoa Peru, Cempro Tech and Norconsult Peru.

Alstom, RusHydro in Russian hydropower agreement

ALSTOM POWER HAS SIGNED A strategic cooperation agreement with Russian power generation company RusHydro that will see the !rms work together to exploit opportu-nities in the booming Russian hydro-power industry.

The agreement covers four key direc-tions of cooperation: reconstruction and modernisation of the Kubanski

cascade hydropower complex in Southern Russia; cooperation for the development of hydropower activi-ties; cooperation in areas of R&D and investment; and local manufacturing of hydropower equipment in the Republic of Bashkortostan, Russia.

The Kubanski cascade project will include the installation of a new instru-mentation and control system as well

as a site security system, following an earlier Memorandum of Understanding (MoU) signed between the two parties in September 2010.

The agreement was signed yester-day in the presence of Vladimir Putin, Russian Prime Minister, Francois Fillon, French Prime Minister, Sergei Shmatko, Russian Energy Minister, Patrick Kron, Chairman and CEO of

Alstom and Philippe Joubert, President of Alstom Power.

As well as the agreement with RusHydro, Alstom also signed deals with other major Russian energy com-panies that will see the company pro-vide power generation products and services for Russias thermal power generation, nuclear power generation and electricity transmission sectors.

WWW.WATERPOWERMAGAZINE.COM JANUARY 2011 5

WORLD NEWS

THE ENVIRONMENT COURT HAS approved resource consents for Trustpowers two new hydro schemes on New Zealands South Island Arnold on the West coast, and Wairau in Marlborough.

The proposed 46MW Arnold scheme will generate enough electric-ity to make the West Coast largely self suf!cient, reducing transmission losses and improving security of supply. It will use generators in an 18km canal running from the existing Arnold hydro dam and then returning water to the river. The primary release back to the river from a regulation pond will be via an international standard White Water course, which, once constructed, will be operated by a community trust.

TrustPower will now carry out detailed technical design and geotech-nical work prior to presenting its devel-opment case to its Board of Directors for approval. That work is expected to be complete within 12 months, allow-ing construction to potentially begin in 2012. During a projected 18-24 month construction phase, the Arnold project will result in a significant increase in jobs and expenditure for the West Coast economy, as the con-struction work will be labour intensive and require an estimated workforce of up to 200. The scheme is estimated

to cost around $180 200M.The proposed 72MW Wairau

scheme will divert water from the Wairau River above the existing 11MW Branch River hydro scheme, though a 49km canal and six gen-erators, before returning the water to the river. The existing 1 Branch River hydro Scheme consists of a 7.2MW power station on the banks of the Wairau River and a 3.8MW station on the Branch River, a tributary of the Wairau.

The Wairau scheme is also designed to improve security of supply and reduce transmission losses as more electricity will be generated locally rather than import-ing it from other regions. Currently only 16% of Marlboroughs energy is produced locally. The addition of the Wairau scheme will increase this to over 40%, through the addition of the schemes generation capacity produc-ing 367GWh per annum.

The scheme includes the provision of two dedicated recreational areas for public use, and estimates of the cost of the project are in the range of $280 320M.

The Arnold project will precede Wairau, with detailed geotechnical studies and technical design for the Wairau scheme expected to take up to two years.

Environment Court approves TrustPower hydro schemes

From the EditorDear readers,

Welcome to the first issue of International Water Power & Dam Construction of 2011. This issue youll see we focus on the areas of dam engineering and tunnelling, both hot topics in the industry right now. Construction has started recently on some major hydro schemes which require extensive tunnelling work, and we take a look at just a few of these in our project update article starting on p24. Here youll discover how a range of challenges have presented themselves to project developers in terms of scale, layout and ground conditions. It is interesting to note how these challenges have been addressed and the different methods being used on these projects. Sharing such experiences is invaluable for other project developers as it offers an important reference should similar problems be encountered elsewhere.

This issue is also brought to the forefront in an article by South African civil engineer Jack Caldwell starting on p12 that looks at the construction of tailings dams. In a no-holds barred piece, Caldwell lets us know what he thinks are the key points in building a successful tailings dam, and details lessons learned from dam failures. Could his ideas help you in building your tailings dam projects?

Another special feature included this month is our listing of the 20 most influential people in dam engineering over the last 10 years. This listing was compiled using your nominations, with the final line-up decided by the IWP&DC team. We had a great response to our call for nominations, and it was interesting to see there was a great cross-section of people nominated, with each person included having received multiple nominations.

Please take a look at the list and share your thoughts with me. Im always interested in receiving correspondence from our readers its important we get your views on the subjects we cover in the magazine. Do you agree with the final line-up? Do you think other people should have been included? What other listings do you think we should look to publish? Email me at the address below or tel: +44 (0) 208 269 7777.

I look forward to hearing from you.

Best wishes Carrieann Stocks Editor Email: carrieannstocks@globaltrademedia.com

EBRD loan for Macedonia

THE EUROPEAN BANK FOR Reconstruction and Development has approved a EUR6M loan to Mali Hidro Elektrani d.o.o. (MHE), a locally-owned renewable energy company, to !nance the development of seven small hydro power plants in the country.

Located on seven different rivers throughout the country the power plants will have a total generation capacity of up to 5.83MW and will pro-duce on average about 21,630MWh of electricity per year.

MHEs generating facilities will be interconnected to the Macedonian distribution grid and the company will bene!t from the preferential purchase agreements with the Macedonian Transmission System Operator and special tariff scheme for renewable energy projects.

This investment is EBRDs !rst pri-vate sector energy generation invest-ment in FYR Macedonia and it is being !nanced through the Western Balkans Sustainable Energy Direct Funding Facility. Upon completion, the project will lead to reduction of CO2 emis-sions estimated at close to 14,000 tonnes per year.

The project is complemented by technical assistance funds provided by the Western Balkans Fund, the EBRD Shareholders Special Fund and the Norwegian government. Upon successful completion of the project, MHE will be eligible to receive an incentive payment for reducing the CO2 emissions of the Macedonian power sector. This incentive payment is provided by the Western Balkans Fund, the EBRD Shareholders Special Fund and the EU.

6 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

WORLD NEWS

In briefRUSSIAN ELECTRICITY !rm EuroSibEnergo and China Yangtze Power Co have agreed to establish a joint venture to build new hydroelectric projects in Russia. According to reports from RIA Novosti, the JV will be established on a parity basis, and will investigate the develop-ment of six projects over the next three years with an installed capacity of over 10,000MW. China Yangtze is then expected to arrange !nancing from Chinese lenders, depend-ing on the outcome of project feasibility studies.

AFTER RELYING exclusively on thermal generation for more than 110 years, Indian power company CESC has announced plans to diversify into hydroelec-tricity generation with involvement in the 90MW Jarong hydro scheme in Arunachal Pradesh. The project, which has already received approval from the Arunchal Pradesh Government, will involve the construction of a diversion barrage across the river Siyom near the village of Jarong

PROFESSIONAL SERV-ICES !rm SMEC has been awarded a contract to carry out feasibility studies for a pumped storage addi-tion to the 360MW Magat hydroelectric project on the island of Luzon in the Philippines. The Magat power facilty draws water from the Magat dam, a large rock-!ll dam on Magat River, a major tributary of Cagayan River. The Magat project is owned and operated by SN Aboitiz Power (SNAP).

Small hydro studies get fundingTHE PROVINCIAL GOVERNMENT of Newfoundland and Labrador in Canada has approved funding of $2.5M to study the potential for small-scale hydroelectric projects.

T h e f u n d s , p r o v i d e d t o Newfoundland and Labrador Hydro (NLH), will study projects that would benefit Labrador coastal communities.

Our government recognizes the need for reliable and clean power for residents of Labradors coastal communities, said the Honourable Kathy Dunderdale, Minister of Natural Resources. Newfoundland and Labrador Hydro has been studying the use of small-scale hydroelectric developments which could provide reliable, clean and available power to coastal communities and the results have been encouraging. We are pro-viding $2.5 million for the continua-

tion of this research in order to further explore the natural resources of Labrador and their potential to provide power to surrounding communities.

The Coastal Labrador Alternative Energy Study was conducted by NLH to determine if alternative energy projects might be feasible to provide power to Labrador coastal communi-ties. Results of this study were posi-tive and Newfoundland and Labrador Hydro believes further work is warrant-ed to explore the potential of small-scale hydroelectric development in greater detail.

Many of the Labrador coastal com-munities are serviced by diesel stations which provide electricity to residents, said the Honourable John Hickey, Minister of Labrador Affairs. While the Provincial Government provides almost $20M annually through grants and subsidies for electricity users in these

communities, we are hopeful that this study will provide alternative methods of providing reliable and clean power to these households.

Through the Northern Strategic Plan, the Rural De!cit Subsidy, the Rate Deferral Subsidy for Diesel Service Areas and the Enhanced Home Heating Rebate, the Provincial Government has endeavoured to keep rates in coastal communities as low as possible and comparable with the Labrador Interconnected residen-tial rate. Budget 2008 also provided $250,000 to support the Coastal Labrador Alternative Energy Study.

Further to the research to be carried out by NLH, the Northern Strategic Plan committed to reviewing commercial rates in Labrador coastal communities with the view of introduc-ing a comparable rate upon sanction of the Lower Churchill Project.

Voith wins Venda Nova III contract

VOITH HYDRO, AS THE LEADER in a consortium with Siemens Portugal, is to supply the com-plete electromechanical equipment for two reversible pumped storage units at the Venda Nova III project in Portugual following the award of a EUR122M contract from Energias de Portugal (EDP).

The company will supply two pumped storage units with variable speed, each with 380MW rated power in turbine mode, two asyn-chronous motor generators with a rated capacity of 420 megavolt ampere, frequency converters, con-trol system and the hydraulic steel structures.

Thanks to their variable speed, the pumped storage units of Venda Nova III can adapt their number of revolutions continuously and take capacities from the grid in the range between 319 and 380MW. Units

with !xed speed do not provide this range their pumping power is regu-lated with the aid of further units or plants. For the development of wind power, whose supply capacities are intermittent and not precisely predictable, providing flexible reserve, however, plays a crucial role. In combination with variable speed pumped storage, wind power plants become more reliable and more pro!table.

Venda Nova III is a milestone in hydro power: variable speed technology supports direct grid con-trol, commented Dr. Siegbert Etter, Executive Vice President Technology of Voith Hydro Holding. In the era of renewable energies this is the new role pumped storage plants are playing.

Venda Nova III is expected to be connected to the grid in early 2015 to support wind power in Portugal.

NIB finances new hydro station in Greenland

THE NORDIC INVESTMENT BANK (NIB) has approved a EUR 33.5M loan to the Greenland Self Rule Government to finance the construction of a new hydropower station near Sisimiut, on the western coast of Greenland.

The 15-year-maturity loan will help fund the construction of the new plant, which was of!cially opened in April 2010. The plant is expected to generate 52GWh this year and will

replace two diesel generators in the town of Sisimiut.

Due to its geography and climate, Greenland is dependent on local electricity production. Until now, the diesel generators have been the only source of electricity for the 6,000 inhabitants of Sisimiut.

We are pleased to be a contrib-uting factor to the shutting down of the fossil fuel run power station in Sisimiut. The new hydropower

plant will silence the polluting diesel generators, leading to improved air quality, lower noise levels, and not least access to more reliable and affordable electricity for the popu-lation of Greenland, says Nordic Investment Banks President and CEO Johnny kerholm.

The Green land Se l f Ru le Government will on-lend the NIB-loan to the local energy company, Nukissior!it.

Nam Theun 2 inaugurated

THE 1070MW NAM THEUN 2 transbasin hydropower scheme was of!cially inaugurated in Lao PDR in early December 2010.

The project a long-term collabo-rative effort between Lao PDR and neighbouring Thailand diverts the upper flow of the Nam Theun river from the Nakai plateau, into the Xe Bang Fai river in the Khammouane plain in Lao PDR. It is capable of pro-ducing 6000GWh per year.

Over 90% of the electricity gener-ated by the project is being sold to Thailand, providing Lao PDR with a $2B revenue stream over the next 25 years. Commercial experts of electric-ity began back in March last year.

Laotian leaders were joined by Thailands prime minister Abhisit Vejjajiva as well international leaders at the inauguration ceremony.

8 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

LETTERS TO THE EDITOR

Dear Editor,

I was interested to read the various comments in your recent article on the WCD ten years on (IWP&DC November 2010). After the release of the report of the World Commission on Dams (WCD) in November 2000, the South African National Committee on Large Dams (SANCOLD) initiated a symposium on the topic to ascertain the applicability of the WCD recommendations within a South African context. At the same time environmental lobby groups requested the Minister of Water Affairs to hold a multi-stakeholder workshop on the WCD. These ini-tiatives were combined in a single process as described below.

A multi-stakeholder symposium was held in July 2001, to establish the gap between South African practice and the WCD report. The sympo-sium concluded that it is broadly supportive of the WCD priorities and a multi-stakeholder steer-ing committee was established to investigate and document the gaps between South African practice and the WCD strategic priorities.

Several meetings and forums were held and this action culminated in the Substantive Report on Applying the World Commission on Dams Report in South Africa, November 2004. A summary report on the topic can be download-ed from the SANCOLD website, www.sancold.org.za under archived news.

During this WCD review period, the Department of Water Affairs undertook a social audit on a number of dams to ascertain issues relating to relocation/resettlement and compensation. Remedial actions were determined.

Just prior to the release of the WCD Report, the Berg Water Project, which included a large dam for the augmentation of water supply to the City of Cape Town, was ready for Ministerial approval to implement. The WCD report neces-sitated a review of the planning process to ascertain the degree of compliance with the WCD guidelines. It was concluded that the planning process did indeed meet, and in some instances exceeded the guideline requirements and project implementation was approved. The Berg Water Project was completed in November

2007. The implementing authority and owner (Trans Caledon Tunnel Authority) is currently undertaking a study to determine project com-pliance with the WCD report. Transparency International together with the World Bank has undertaken a case study on the project with a particular focus on governance, sustainability and communication, all of which are elements of the WCD report.

The purpose of the South African multi-stake-holder initiative was to build consensus on how we should respond to the WCD report and how here in South Africa we can improve our deci-sion-making on dams the ultimate purpose of the whole process.

It is gratifying to report that many of the recommendations of the SA Multi-Stakeholder Initiative have now been incorporated into the normal procedures for the planning and imple-mentation of large dams.

Paul RobertsSecretary: SANCOLDsecretary@sancold.org.za

Dear Editor,

We are indeed very familiar with the history of the World Commission on Dams (WCD) because the Swiss Committee on Dams, as one of the 90 member countries of ICOLD, was directly con-cerned in this process.

Many comments on the WCD report were pub-lished during the three years following the confer-ence of 16 November 2000 in London, where the report was launched. The most important assess-ments were issued by large and very experienced international organisations, such as: ICOLD, the International Commission on Irrigation and Drainage (ICID) and the International Hydropower Association (IHA).

Great attention was given to the analysis of the report and some synthetic conclusions were drawn, with all the necessary nuances. The detailed state-ment of the Swiss Committee after the publication of the WCD Report in 2001 has not changed.

The WCDs objective was to provide a frame-work for options assessment and decision-making in water and energy development, and to set out criteria and guidelines for the design, construction, operation and decommissioning of large dams. Another objective was to bring new voices into the procedure, in order to win greater public acceptance.

While this intention may have been laudable, it appeared, and the article of Patrick McCully [2] is clear on that matter, that the initiators of the proc-ess (principally the International Rivers Network International Union for Conservation of Nature and Natural Resources and the World Banks Operations Evaluation Department) were strongly in!uenced by extreme anti-dam NGOs. The organi-sation of the WCD was thus biased and its various

elements were manipulated (such as the appoint-ment of commissioners, choice of case studies, regional consultations, forum meetings and publi-cation of the "nal report), and considered unfair.

We should highlight the efficient actions of one particularly skilful gentleman, Achim Steiner who was Secretary General of the WCD. In 2001 he became Director General of the IUCN, and in 2006 he was appointed as Executive Director of the United Nations Environment Programme (UNEP). We hope that today, in his important posi-tion, he has not forgotten the message eloquently expressed by Nelson Mandela at the WCD launch:

The problem, though, is not the dams. It is the hunger. It is the thirst. It is the darkness of a town-ship. It is township and rural huts without running water, lights or sanitation. It is time wasted in gathering water by hand. There is a real pressing need for power in every sense of the word.

Finally there was no consensus on the com-mission report, and the WCD decided that an intense phase of dissemination would be under-taken to convince governments, "nancial institu-tions and the private sector to adopt the WCD guidelines. The reaction was globally negative, and the guidelines were explicitly rejected by major institutions, including the World Bank, and especially by the developing countries.

The total expenses of the WCD totalled about US$10M [3], mainly "nanced by governments and aid agencies (63%), foundations and NGOs (16%). In addition several million dollars were spent later on dissemination of the report.

Nobody can be proud of this very expensive and unsuccessful exercise, and we have no reason to blow the trumpet of the WCD for a tenth non-event.

To "nish on a positive note, we can observe

that since 2000, the countries that needed dams and wanted to continue to build them did so. Those who looked for an excuse not to build them delayed some projects, with the associ-ated negative effects on local populations and national economies in terms of delayed water and energy bene"ts.

In 2000, the number of large dams in the world was 45,000; over the past ten years there has generally been a steady increase in dam con-struction up to 50,000, and more than 330 major dams higher than 60m are under construction today. By 2050 the total number of large dams is estimated to reach 65,000.

There is an essential reason for this: precipita-tions on our Blue Planet are not equally distrib-uted in time and space. It is therefore essential to store runoff water to meet basic human needs, without of course neglecting a fundamental cul-tural aspect: the environment.

Yours sincerelyProfessor Anton SchleissPresident, Swiss Committee on Dams

[1] ICOLD. About the WCD Report Dams and Development. (2001)

[2] P. McCully. The use of a trilateral network: An activists perspective on the formation of the World Commission on Dams. American University International Law Review 16. (2001) .

[3] WCD. World Commission on Dams Project. Financial Report. March. 1998-April 2001.

Send your letters to the editor via email carrieannstocks@globaltrademedia.com

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PLANNING AND PERMITTING

F INANCIAL ANALYSIS

PRELIMINARY AND DETAILED DESIGN

Let IWP&DCs readers know about your forthcoming conferences and events. For publication in a future issue, send your diary dates to: Carrieann Stocks, IWP&DC, Global Trade Media Ltd, Progressive House, 2 Maidstone Road,

Foots Cray, Sidcup, Kent, DA14 5HZ, UK. Alternatively, email: carrieannstocks@globaltrademedia.com, or fax:+44 208 269 7804

DIARY OF EVENTS

10 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

DIARY

February15-17 February6th International Conference on Dam EngineeringLisbon, Portugal

CONTACT: Eliane Portela , LNEC, Concrete Dams Department, LNEC, Av. Brasil 101, 1700-066, Lisbon, Portugal.Tel: (351) 218443361.Fax: (351) 218443026.Email: eliane@lnec.pt.http://dam11.lnec.pt.

22-24 FebruaryUnderwater Intervention 2011New Orleans, LA, US

CONTACT: U n d e r w a t e r Intervention 2011 Committee , 5206 FM 1960 West, Suite 202 Houston, TX 77069 USA.Tel: +1 281-893-8539. Fax +1 281-893-511.Email: rroberts@adc-int.org.www.underwaterintervention.com.

March8-9 MarchPTK 2011: Norwegian Power Production ConferenceOslo, Norway

CONTACT: Energy Norway, PO Box 7184 Majorstuen, N-0307 Oslo, Norway.Tel: +47 23 08 8900.Email: ptk@energinorge.no.

15-16 MarchCase Studies Workshop: Learning from International Dam Incidents and FailuresLas Vegas, Nevada, US

CONTACT: CEATI International, 1010 Sherbrooke St W, Suite 2500, Montreal, QC, Canada, H3A 2R7.Email: workshops@ceati.com.www.ceati.com/Meetings/DS2011/index.html.

28-30 MarchHydroVision RussiaMoscow, Russia

CONTACT: Mathilde Sueur, Conference Manager, PennWell.Tel: +44 1992 656 634.

Fax: +44 1992 656 735.E: mathildes@pennwell.com.www.hydrovision-russia.com.

April11-15 AprilUnited States Society on Dams 2011 Annual Meet ing and ConferenceSan Diego, California, US

CONTACT: United States Society on Dams, 1616 Seventeenth Street #483, Denver CO 80202, USTel: +1 303-628-5430.Fax: +1 303-628-5431.

13-15 AprilSmall Hydro 2011Vancouver, Canada

CONTACT: Ms Eman El-Labban, Arena International.Tel: +44207 336 5248.Email: EmanEl-Labban@arena-international.com.http://www.arena-international.com/smallhydro.

15-17 AprilEnergy Ef!ciency and Renewable Energy Sources for South-East EuropeSo!a, Bulgaria

CONTACT: Via Expo Ltd, 3 Chehov Square, Plovdiv 4003, Bulgaria.Fax: +359 32 945 459.Email: of!ce@viaexpo.com.http://viaexpo.com.

May5-7 MayHydroVision IndiaNew Delhi, India

CONTACT: Amanda Kevan, PennWell Corp, United Kingdom.Tel: +44 1992 656 645.Fax: +44 1992 656 700.Email: amandak@pennwell.com.http://www.hydrovisionindia.com.

16-20 May2 5 t h E u r o p e a n R e g i o n a l Conference of ICIDGroningen, The Netherlands

CONTACT: Bert Toussaint,

Chairman of the Organizing Committee, Ministry of Transport, Public Works & Water Management, Rijkswaterstaat Centre for Corporate Services, PO Box 2232, NL-3500 GE Utrecht, NetherlandsTel: +31 62 079 1372Email: bert.toussaint@rws.nl.www.nethcid.nl.

23-26 MayHidroenergiaWroclaw, Poland

CONTACT: European Small Hydropower Association (ESHA).Tel: +32 2 546 1945 .Fax: +32 2 546 1947.Email: info@esha.bewww.esha.be.

29 May - 3 June79th Annual Meeting of ICOLDLucerne, Switzerland

CONTACT: Swiss Committee on Dams, c/o Stucky Consulting Engineers.Email: swissdams@stucky.chhttp://www.swissdams.ch

June7-9 JunePower-Gen Europe 2011Milan, ItalyCONTACT: PennWell Publishing UK Ltd, Warlies Park House, Horseshoe Hill, Upshire, Essex, EN9 3SR, UK.www.powergeneurope.com.

14-17 JuneIHAs 2011 World CongressIguassu Falls, Brazil

C O N T A C T : I n t e r n a t i o n a l Hydropower Association, Nine Sutton Court Road, Sutton, Surrey. United Kingdom, SM1 4SZTel: +44 20 8652 5290.Email: congress@hydropower.org.http://www.hydropower.org.

15-18 JuneII Optimization of Constructions Methods of CFRDsYichang, China

CONTACT: HydrOu China, No 41-210 Three Gorges Community, Zhenping Road, Yichang city, Hubei

443002, China.Tel: +86717 672-2137.Email: hydrou@hydrou.com.http://hydrou.com.

20-21 JuneAPEMEC 2011 (Small Hydro Trade Fair & Conference)Santiago, Chile

CONTACT: APEMEC.Tel: +56 2 344 0044Email: info@apemec.clWebsite: http://www.apemec.cl

July19-22 JulyHydroVision 2011California, US

CONTACT: Libby Smith, Conference Manager, PennWell.Tel: +1 (918) 831-9560Email: hvconference@pennwell.com

September5-7 September3rd Australasian Hydro Power ConferenceQueenstown, New Zealand

CONTACT: John Schurink.Tel: +64 3 3646607.Email: schurinkj@mace-eng.co.nz.www.hydroconference.co.nz.

25-28 SeptemberSeminar on Operat ion and Maintenance of CFRDsYichang Three Gorges, China

CONTACT: HydrOu China, No 41-210 Three Gorges Community, Zhenping Road, Yichang city, Hubei 443002, China.Tel: +86717 672-2137.Email: hydrou@hydrou.com.h t t p : / / h y d r o u . c o m / i n d e x .php/2010080760/Workshop/ optimal-operation-management- on-cfrds.html

25-29 SeptemberDam Safety 2011Washington DC, US

CONTACT: Association of State Dam Safety Of!cials.info@damsafety.org.www.damsafety.org.

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12 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

DAM ENGINEERING

The tail end of a storyBorn on a gold mine in South Africa, Jack Caldwell grew up around the slimes dams. He was educated as a civil engineer on a mining scholarship at the University of the Witwatersrand, Johannesburg. Since then he has consulted with mine owners the world over on the design, operation and closure of tailings impoundments. Here he gives a personal and straight-talking account of how to build successful tailings dams

THE Teton dam failed in Idaho in 1976. It had been designed by the US Bureau of Reclamation and a group of experienced dam engineers. Eight years later, and I had just been retained to help design and construct the Cannon Mine tailings impoundment in Wenatchee, Washington state. Our site had the same rock strata as those that had piped and reportedly caused the failure of the Teton dam. Preliminary analyses showed that we needed an embankment at least 91m high to retain the tailings. The embankment eventually

rose to a height of 103m, making it the highest privately owned dam in Washington.

Then, as now, tailings dams failed at a far greater rate than conventional water-retaining dams; and their failure caused great damage. We were nervous. Syd Hillis came to our rescue. He had been the chief geotechnical engineer on Tarbela, the largest earthern dam in the world. He had also been the chief geotechnical engineer for the Revelstoke dam, then the highest earth dam in the world. Now he was a private consultant and a peer reviewer of dams funded by the Asian Development Bank.

We met; we argued; we fought; and we became !rm friends. I moved to Wenatchee to design the dam as we went. There was no money in the mines budget for site investigation, we did it as we stripped the soils. Syd came down once a month. He walked the site with me. He

Below: The author stands at Greens Creek dray stack tailings impoundment in Alaska. A filter-pressed, dry stack approach is becoming more popular and an ideal way to dispose of tailings in a safe, sound and environmentally protective manner

WWW.WATERPOWERMAGAZINE.COM JANUARY 2011 13

DAM ENGINEERING

felt and tasted the soil; who is allowed to do that these days? And he insisted on conservative measures: !lters placed every place piping was conceivable; !lters upgradient and downgradient of the core, just in case cracking occurred; compacted rock!ll; and large drains. The embankment was built above some 20,000 homes and stands today, reclaimed and the home of the Dry Gulch Riding Stables.

Proud as I am of this embankment that was built to the high-est standards of any water dam, I have to admit that long before this I had designed a tailings impoundment that failed some years after initial construction. That was for the De Beer Diamond Mine in Kimberley, South Africa. Nobody was hurt; no environmental damage was done; it is not even listed in those long lists of tailings dam failures you !nd on the web.

I had started a life-long career in tailings dams as a child in South Africa, doing the forbidden riding around slimes dams of the mine where I grew up. My !rst job out of university was supervising the pouring of concrete for construction of the Hendrik Verwoed dam on the Orange River. That dam is now called the Gariep dam in honour of vast political change in South Africa.

As a masters student at university, I helped Professor Jennings investigate the failure of the Bafokeng slimes dam that killed 13. I got to talk so fast, they gave me the job of designing the new one; it is still in operation and easily seen on Google. But the difference between the attention paid to the design, construction, and operation of the Hendrik Verwoed dam and the Bafokeng dams, old and new, readily established why tailings dams fail more frequently than water dams.

Now nearly 65 years of age, I still consult on tailings dams. I am currently involved with tailings dams in Guatemala, Alberta, the Northwest Territories, and a small country in Africa that prefers to remain unnamed. I am obsessed with potential failure of the tail-ings facilities that I touch, and hence I write to explore reasons why tailings dams fail so often. And I seek ways to prevent the terrible frequency of tailings dam failure. Here are few ideas.

FAILURE OF A SYSTEMI am no fan of attempts to ascribe failure of earth embankments, whether for tailings or water, to single causes. You know the typi-cal list: foundation sliding; differential settlement; too much water; overtopping; piping; bad design; and so on. On the basis of real-life experience and much reading and thinking, I must conclude that the failure of dams, for tailings and water, is a failure of the system. That is the system by which the dam is regulated, permitted, designed,

constructed, operated, monitored, and closed. I believe that we need the following to reduce dam failure: good

laws and regulations; the best designers and engineers; plus consistent and regular peer review.

In the absence of good laws and clear regulations, the designer is adrift subject to the whims and whiles of owners who seek to reduce costs, cut corners, and do less than is necessary. Right now I am fretting over a water-retaining structure that was designed where there is no law, and the least possible was done. The dikes are failing and I am faced with telling the owners to spend a lot to upgrade or abandon the facility and build a new one. I am not popular and may be replaced by other consultants. So be it.

If the regulator is inexperienced, uneducated, or inattentive, they will permit any bad old design presented to them. They fail their public trust and duty. In too many countries where mines are devel-oped, it is a simple matter to beguile the regulator, or worse to bribe them. The resulting dams are at high risk of failure.

Sad to say, but there are good consultants and there are bad consultants. There are too few good consultants to do all the work. Bad consultants do design dams and these often fail. Such facts are not listed in causes of failure, but I challenge investigators and historians to test my thesis that bad designers are a signi!cant con-tributor to dam failure.

Then we have failure to peer review. Syd Hillis taught me the value of peer review. Without him, the Cannon Mine dam would not be what it is: safe and secure and likely to last for as long as I can con-ceive a new geomorphic form in the landscape. I have produced designs that have been reviewed by other peers. When you assemble a team, at least three strong, of honest engineers, you cannot but suc-ceed. As an owner you are assured things are properly done; as the design engineer, you know you are up to par; and as a member of the public, you can be assured you are safe. Thus I list these minimum desiderata for a safe dam, for water and/or for tailings:

r Appropriate laws and regulations.r Trained and conscientious regulators and permit granters.r The best design engineers you can assemble and afford.r Focus on site selection, site characterisation, testing, and analyses,

more analyses, and profound judgment.r Peer review at every stage of design, construction, operation

and closure.

Above: A prototype cover for Suncor pond 5 tailings in Alberta

14 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

DAM ENGINEERING

r Informed and interested operators, who measure, monitor and report every observation.r A maintenance and monitoring plan that can be communicated,

understood and implemented. r Transparency and regular reporting to a public body that posts the

reports of design and operation on a readily accessible web site.

My theory is that no dam fails for a single reason. In every case of failure that I have been associated with, there are at least ten things that went wrong before failure occurred. I know from personal expe-rience, that at all dams there are always ten things wrong. But not all dams fail. It is only when the stars malignantly align, when the ten wrong things line up in a negative way, that failure occurs and people die. (Nothing new or insightful in this observation/conclu-sion.) Standard accident avoidance theory and practice is that for every 100 incidents, there is one accident. For every 30 accidents, there is one death (the ratios vary depending on whom you believe but the idea is sound.) It is the obvious pyramid of events: control the incidents, and you eliminate the accidents and deaths.

If an incident is de!ned as a small, irritating occurrence with no par-ticular consequence, you may readily and graciously investigate the incident and put in place practices to prevent recurrence. I learnt this as chief geotechnical engineer on closure of the Operating Industries Land!ll just to the east of Los Angeles. This 526,000m2 land!ll is the largest hazardous waste land!ll on the US Environmental Protection Agencys superfund list. The slopes rise at 1.4: 1.0 that is steep. And the slopes rise some 91m above I60, a six-lane freeway exiting the city. The land!ll is underlain by an active fault. I felt an earthquake one day, and we swayed like jelly on the soft waste beneath.

I was digging and pro!ling test pits on the steep slopes. A clod broke free of the pile of excavated soil. The clod rolled down the slope, jumped onto the freeway and hit the side of a passing car. It indented the car door, leaving a dirty brown patch. This incident was carefully investigated. The result: a US$100,000 plywood bar-ricade between the land!ll and the freeway. We went on to complete US$100M of work safely. We owe our success to Jill Saminago who, as our health and safety of!cer, insisted on incident investigation and control as the way to save lives.

The lesson learnt from that story is that at every dam, at every stage of construction and operation, have and implement an Incident Control Plan.

According to my agreement with the editor of this magazine,

I have but !ve-hundred words left to make my case. Let me use these remaining words to acknowledge Terzaghi and Peck. Terzaghi is the father of soil mechanics; it is he who !rst enunciated the basic princi-ples of the control of soil and the "ow of "uids through soils some-thing that happens at all dams. Starting as a professor in Vienna in the 1930s, he went on to a career as a soils mechanics and dam design consultant. He is coauthor with Peck, his student, of what is still the best book on the topic today, namely Soil Mechanics in Engineering Practice. Recently updated by Mesri, it is still on my shelf; I read sec-tions every so often to remind me of good practice; I make all young engineers who come my way read it so that we have a common basis of understanding.

Terzaghi taught the professor who taught me geotechnical engi-neering. In Albuquerque, my of!ce overlooked the suburb in to which Peck retired; he often came to the local engineers meetings and chat-ted with all of us as locals, as we all were. From him and his writ-ings, alone and with Terzaghi, I learnt the dangers of the overlooked geological discontinuity, and the immense value of the observational method.

The observational method is easy to state and understand. It is ter-ribly dif!cult, however, to compile and implement an Observational Method Plan. I have worked on two: one done informally; one done most carefully and formally. Most other attempts I have observed have used the words, but failed miserably to catch the intent or apply the power of the method.

Nevertheless, I must end by insisting that if you want to preclude failure of your dam, for tailings or water, you must struggle, strive, and !ght to write and implement an Observational Method Plan. The reality is that dams are geotechnical structures. We cannot estab-lish perfection in geotechnical conditions; we can make only faint attempts to model and predict performance; we must therefore moni-tor and adjust in accordance with a pre-existing plan to the actual conditions and behaviour of our dam as it is built, !lled, operated, and taken safely to closure.

Jack Caldwells blog on mining and tailings dams can be found at www.ithinkmining.com

Email: jcaldwell@robertsongeo.com

Above: Upstream side of Ekati Long lake containment facility. A throughflow rock dike forms the tailings impoundment

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DAM ENGINEERING

Major advance for minimum energy loss culverts A signi!cant advance in culvert design was the development of the minimum energy loss culvert in Australia 50 years ago. Hubert Chanson illustrates how it proves to be a testament to hydraulic engineering expertise

16 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

CULVERTS are among the most common hydraulic structures and were used for more than 2000 years. For example the Romans built a number of culverts to pro-tect road embankments as well some aqueducts. A cul-vert is simply a covered channel designed to allow waters beneath an embankment and to carry safely the !ood waters underneath the earth"ll structure. Modern designs differ very little from the Roman culverts and they are too often associated with a signi"cant af!ux at design !ows (The af!ux is the rise in upstream water level caused by the presence of a hydraulic structure.)

During the late 1950s, a new culvert design was developed in Australia the minimum energy loss (MEL) culvert (McKay 1971, Apelt 1983, Chanson 2007). The MEL culvert design aimed to achieve a minimum af!ux by streamlining the entire waterway and operating at critical !ow conditions for the design discharge.

In this paper, the performances of MEL culverts are reviewed and discussed. Their successful operation over several decades demon-strates a sound design and their experience highlights the hydraulic expertise of the designers.

DEVELOPMENTThe design of the minimum energy loss culvert was developed by late Professor Gordon McKay (McKay 1971). The design is based upon the concept of minimum head loss and nearly constant total head along the waterway. The !ow in the approach channel is contracted through a streamlined inlet into the barrel where the channel width is minimal, and then is expanded in a streamlined outlet before being "nally released into the downstream natural channel. The inlet and outlet must be streamlined to avoid signi"cant form losses.

The MEL culvert design implies a waterway operation at critical or trans-critical !ow conditions from the inlet lip to the outlet lip for

the design !ow rate. Indeed, the critical !ow conditions in an open channel provide the largest discharge per unit width for a given speci"c energy (Henderson 1966, Chanson 2004). In practice, the barrel invert is lowered as sketched in Figure 1 to increase locally the speci"c energy, hence the discharge capacity.

The basic design parameters of a MEL culvert are the design !ow rate Qdes, the upstream speci"c energy Eo in the !ood plain in absence of culvert, and the maximum acceptable af!ux. For a MEL culvert design with zero af!ux, the width of the inlet lip must satisfy the Bernoulli principle:

Zero af!ux (1)

where Bmax is the inlet lip width measured perpendicular to the !ow streamlines and the upstream speci"c energy in absence of af!ux equals:

(2)

In the inlet and outlet, there is an unique relationship between the width B and the excavation depth z (Apelt 1983, Chanson 2004). In the throat, the barrel width must satisfy:

Zero af!ux (3)

where zo is the barrel excavation depth.

The inlet and outlet are designed using a !ow net analysis based upon the irrotational !ow theory (Vallentine 1969, Chanson 2009). Figure 2 illustrates a culvert inlet. The contour lines, or lines of constant invert elevation, are the equi-potential lines that must be perpendic-ular to the !ow streamlines everywhere. The design theory is well understood for man-made structures with rectangular cross-sections (Apelt 1983).

Practically, the MEL culvert design is selected only if it is cheaper than a standard culvert design. The cost of the entire structure is connected with its design speci"cations including the design !ow, upstream design head and maximum af!ux, the topography and construction costs, and the total costs. In Australia, the experience indicates that the MEL culvert design compares favourably for long culvert barrels and in !at !ood plains with limited available af!ux, despite the higher design costs.

Inletfan

Outletfan

Barrel

BarrelInlet Outlet

Inletlip

Outletlip

Bmin

Bmax

T.H.L. (Nature's flood plain)

Water level (Nature's flood plain)

Natural bed level

dc

dc

dc

do

do

Vo

do

zo

Nature's flow depthat design floodwith velocity Vo

Barrel Water surface assumedin simple method

Free-surface inreal applications

Lip

Lip

Figure 1: Definition sketch of a minimum energy loss culvert operating at design flow with zero afflux

WWW.WATERPOWERMAGAZINE.COM JANUARY 2011 17

DAM ENGINEERING

PERFORMANCES AND EXPERIENCES

The !rst MEL culvert designs were developed for zero af"ux, and some solid physical modelling was conducted. The culvert models were typically some 1:12 to 1:36 undistorted geometric scale models with !xed bed. These early structures have been in operation for more than 50 years with a range of hydrological conditions including semi-tropical, tropical and arid weather conditions. The characteristics and operational record of a number of MEL structures were document-ed, and this was complemented by some !eld inspections including during "ood events (Apelt 1983, Chanson 2007).

A number of MEL structures were observed to operate at design "ows and for "oods larger than design. The inspections by hydraulic experts during and after the "ood events highlighted the sound operation together with the negligible maintenance requirements. Figures 3A and 3B show a MEL culvert and a MEL waterway operating with discharges less than the design "ow rate (a waterway is a culvert structure without sof!t and cover.) Both structures are located in a catchment in the city of Brisbane in Australia. Their design "ow conditions correspond to an intense rainstorm with a concentration time of two hours yielding a runoff discharge of between 150-220m3/sec. Along the stream (Norman Creek), a total of !ve MEL structures were designed and built to operate with zero af"ux. These structures were part of the re-development of Norman Creek to allow the completion of the southeast freeway.

Figure 3a shows the occurrence of a small hydraulic jump in the inlet: the feature is common to MEL culverts operating with discharges less than the design "ow rate since the throat "ow is subcritical and the inlet "ow is supercritical. At design discharge, the "ow is critical from the inlet lip to the outlet lip including in the barrel, and no hydraulic jump takes place as sketched in Figure 1. Figure 3b highlights the throat and outlet operation that is typi-cally subcritical and relatively smooth for discharges less than the design "ow rate.

Based upon decades of experience, Professor C.J. Apelt stressed that a successful MEL culvert design must follow closely two basic concepts:

r The streamlining of the discharge in, through and out of the culvert.r The trans-critical "ow conditions throughout the entire waterway

for the design "ow rate (Apelt 1983).

Any flow separation and recirculation must be avoided at all cost. In one MEL culvert, some "ow separation was observed in the inlet associated with some "ow recirculation in the barrel: this structure cannot pass more than 50% of its design "ow rate without overtopping. In a MEL structure, the supercritical "ow conditions must be avoided at design "ow rate: this is essential in the outlet where separation must be avoided at any cost. Further model and prototype observations have shown conclusively that MEL culverts can pass safely "ood "ows signi!cantly larger than the design "ow conditions. This is not always the case with stand-ard culverts.

In practice, the MEL culverts must be equipped with adequate drainage to prevent water ponding in the barrel invert. Drainage channels are preferred to drainage pipes. For example, the MEL structure shown in Figure 2 is equipped with a well-designed drainage system seen at the bottom left of the photograph. A worrisome issue is the loss of expertise in hydraulic design. In Brisbane, the operation of two MEL culverts was hampered recently by the construction of concrete piers for a new busway. As a result, a major arterial road is likely to be overtopped during a design "ood because the in"ow streamlining is disturbed by the concrete piers.

A key feature of the MEL culvert design is the small af"ux. While many structures were designed with zero af"ux, the opti-mum design could yield a small, non-zero af"ux (Chanson 2004). The culvert wing-walls and "oor must be adequately protected since the velocities in the culvert are larger than in a conventional culvert. Yet the MEL culvert streamlining yields lower turbulence and a reduced erosion potential: eg some MEL culvert inverts can be made of earth with grassed surface.

Major advance for minimum

Figure 2: Inlet of a MEL culvert looking upstream with students measuring the inlet dimensions on 13/9/2006. Note the low flow channel in the foreground (right)

18 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

DAM ENGINEERING

CULVERT DESIGNThe minimum energy loss culvert design was a major development in culvert design. First developed in Australia, the design is based upon the basic concepts of streamlining the !ow and trans-critical !ow conditions at the design discharge. The resulting design allows a drastic reduction in the af!ux and upstream !ooding, associated with a lower cost.

The successful operation of MEL structures for many years has shown the soundness of the design and highlighted the importance of streamlining throughout the whole structure. Experience has

demonstrated that the design must be based upon expert hydraulic engineering and any subsequent modi"cations of the structure must be carefully analysed to minimise any form of adverse effect on the !ood !ow.

Hubert Chanson, Professor in Hydraulic Engineering, School of Civil Engineering, The University of

Queensland, Brisbane Qld 4072, Australia, Email : h.chanson@uq.edu.au

Figure 3a: Operation of the Minimum Energy Loss culverts and waterway on Norman Creek. MEL culvert underneath the southeast freeway in operation on 20 May 2009. Looking downstream at the inlet (foreground), with a small hydraulic jump typical of a discharge less than the design discharge

Figure 3b: MEL waterway beneath the southeast freeway in operation on 20 May 2009. View from the right bank looking downstream at the throat and outlet (in background) This structure is located downstream of the MEL culvert shown in Figure 3a

ReferencesApelt, C.J. (1983). Hydraulics of Minimum Energy Culverts and Bridge Waterways. Australian Civil Engrg Trans., I.E.Aust., Vol. CE25, No. 2, pp. 89-95.

Chanson, H. (2004). The Hydraulics of Open Channel Flows : An Introduction. Butterworth-Heinemann, Oxford, UK, 2nd edition, 630 pages.

Chanson, H. (2007). Hydraulic Performances of Minimum Energy Loss Culverts in Australia. Journal of Performances of Constructed Facilities, ASCE, Vol. 21, No. 4, pp. 264-272 (doi:10.1061/(ASCE)0887-3828(2007)21:4(264)).

Chanson, H. (2009). Applied Hydrodynamics: An Introduction to Ideal

and Real Fluid Flows. CRC Press, Taylor & Francis Group, Leiden, The Netherlands, 478 pages.

Henderson, F.M. (1966). Open Channel Flow. MacMillan Company, New York, USA.

McKay, G.R. (1971). Design of Minimum Energy Culverts. Research Report, Dept of Civil Eng., Univ. of Queensland, Brisbane, Australia, 29 pages & 7 plates.

Vallentine, H.R. (1969). Applied Hydrodynamics. Butterworths, London, UK, SI edition.

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Audio-visual and Internet resources on Minimum Energy Loss culverts and waterwaysDESCRIPTION (1)

REFERENCE (2)

Audio-visual resources

The Minimum Energy Loss Culvert Apelt, C.J. (1994). The Minimum Energy Loss Culvert. Videocassette VHS colour, Dept. of Civil Eng., University of Queensland, Australia, 18 minutes.

Norman Creek Flood on 7 November 2004 Chanson, H. (2004c). Storm and !ood at Norman Creek, Brisbane (Australia) on 7 November 2004. IAHR Media Library {http://www.iahrmedialibrary.net/}, Urban drainage, video-clip, 6 minutes.

Internet resources

Hydraulics of Minimum Energy Loss (MEL) Culverts and Bridge Waterways {http://www.uq.edu.au/~e2hchans/mel_culv.html}

Design of waterways and culvert structures on Norman Creek, Queensland {http://www.uq.edu.au/~e2hchans/civ4511.html#Project}

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DAM ENGINEERING

Engineering on-the-goNew technology can open the door for new business opportunities. The Engineering On-The-Go concept developed by Eurocom utilises its capable mobile hardware and optimizes the engineering process in a wide variety of industries. It can even shorten the design and development processes involved in dam projects

VARIOUS engineers come together to work on the different aspects of designing, building and operating a dam and its associated components. The team works together and utilises CAD/CAM software, calculates the water !ow in CFD soft-ware, and runs analysis on the forces that play parts of the dam under various situations. All these activities are completed with the use of intense software programs that require high-end hardware to run them.

These activities are executed by different professionals from around the world. The inability of laptops to run these intense software pro-grams, and store and process such large amounts of data, can force the engineering team to work on desktop workstations in their of"ce. Capable mobile computing solutions would allow engineers to per-form such activities in the "eld anywhere in the world.

Performing these engineering activities on-site is possible through Eurocoms capable mobile hardware, says the company. Called Engineering On-The-Go it allows companies to: design or address problems anywhere in the world; offer engineering capacity onsite; receive feedback and make adjustments while being face to face with "nal users, customers, co-developers and other third parties; and reduce time and development costs for projects.

ENGINEERING HARDWARE REQUIREMENTSTo run the intense engineering software programs (for CAD, CAM, CFD, FEA, etc) four components are of the essence for your hardware: memory (RAM), storage, a graphics processing unit (GPU) and the central processing unit (CPU). RAM is necessary to make sure these programs can access the data it needs in a fast way to make them run smoothly. Most analytical programs load all your data and the pro-gram itself into RAM to perform its calculations. Besides improving the speed of the program, large amounts of RAM also allows you to run multiple operating systems on one unit (virtualisation).

The advantage of virtualisation is that you can run your applica-tions in the operating system they perform best without having to buy multiple systems. When buying hardware for engineering software, besides the size of the drives, the speed is another important factor. You can choose between a mechanical drive, solid state drive and hybrid. To improve performance or redundancy of the drives one can choose to con"gure them in different con"gurations.

Another important aspect of hardware when using it for intense engineering activities is the GPU technology. This component is a specialised microprocessor that of!oads and accelerates 3D or 2D graphics rendering from the CPU. For this you want a GPU that is dedicated to running OpenGL technology.

The last feature of your hardware that has a major impact on the performance of your engineering software is the CPU. The number of cores per CPU, the clock speed and the amount of cache are impor-tant indicators for the performance of this component.

KEY SPECIFICATIONS To deploy the Engineering On-The-Go concept, you need capable mobile computing hardware. Some key speci"cations of the mobile

workstation includes: up to 24GB of RAM; a six core Intel i7 980X Extreme processor or a CPU from the XEON 5500/5600 series with up to 12MB of cache and clocks speeds up to 3.33 GHz; up to 3.25TB of storage provided by four physical hard drives; very portable and weighing only 5.3kg including battery; units with up to 18.4-inch full HD displays.

Because no company is the same, Eurocom has de"ned three levels of Engineering On-The-Go implementations.

Engineering On-The-Go consultantThis can be applied by any size of company and only requires a relative-ly small investment in the acquisition of a mobile workstation for the engineer. This piece of equipment allows the user to perform on-the-go consulting activities or test his draft design with customers, co-develop-ers, "nal users and other third parties in the "eld. The direct interaction can reduce the projects costs caused by miscommunications.

Engineering On-The-Go projectsThe second level uses the concept that Eurocom has de"ned as RED-Team. RED-Team stands for Rapid Engineering Deployment and allows companies to deploy a complete team of developers, engineers and designers anywhere in the world. Next to an individual mobile workstation for each of the RED-Team members, the team is also equipped with a Eurocom mobile server to contain the master "le set, back up the data and provide a network for the team members. In this form the company can decide whether or not they deploy a RED-Team at the customer site.

Engineering On-The-Go organisationWith the ultimate form of Engineering On-The-Go, the organisation transforms into a RED-Team enterprise and integrates this concept into their competitive strategy. Every project can be completed on location which makes a head of"ce unnecessary.

Many innovative companies such as Apple, Siemens, Lockheed Martin, Microsoft and Ericsson are currently using Eurocom Mobile Workstations to perform their engineering activities on location and have yielded the bene"ts of combining mobility and capacity.

Eurocom mobile workstations are also being utilised by engineers around the world to design, construct and service state-of-the-art power generation facilities. The power of the mobile work station allows engi-neers to have a fully mobile capability, enhancing productivity and reducing costs, by enabling them to perform their duties on site.

Eurocom mobile workstations are designed for heavy-duty com-puting so they are built like heavy-duty trucks portable yet extremely powerful with maximum upgradeability, expandability, and reliability, says Mark Bialic, president of Eurocom. It is designed for maximum performance and for the most demanding users. CAD/CAM designers and engineers who frequently travel, yet need access to powerful com-puting, are the core target for mobile workstations.

For more details see www.eurocom.com

The Panther 2 mobile

workstation.

IWP& DC

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22 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

DAM ENGINEERING

Influencing engineeringTo celebrate the importance of the dam engineering sector, weve compiled a list of the 20 people we believe have made the biggest difference to the sector over the last 10 years. This list in alphabetical order was compiled using nominations from contacts and readers around the world, and was decided by the IWP&DC editorial team and industry experts

Dr George AnnandaleDr Annandale was the !rst engineer to develop and publish a sci-enti!cally defensible and validated approach to predicting scour of rock. He published a seminal paper in 1995 that forms the basis of the Erodibility Index Method and the understanding of rock scour that developed since then. Over the last 10 years this method has matured through testing, case study validation and re!nement, and has been internationally accepted by the engineering profes-sion for use in the design of new dams and for developing mitiga-tion designs ensuring the safety of existing dams. Dr Annandale authored the book Scour Technology that was published by McGraw-Hill in 2006.

Dr. Anil Chopra Dr Chopra is well known for pioneering methods for earthquake response analysis of structural systems, including dynamic interaction with soils and "uids. He serves as a consultant on earthquake engineer-ing problems to numerous governmental and private organizations.

A professor at the University of California at Berkeley, he has been instrumental in encouraging students to study a number of very tough issues associated with concrete dams (gravity and arch) since the 1980s.

He has authored more than 300 papers on this work, a mono-graph, Earthquake Dynamics of Structures, A Primer, 2005, and a textbook, Dynamics of Structures: Theory and Applications to Earthquake Engineering, 1995, 2001, and 2007.

Mr Don DeereMr Deere has over 30 years of experience in the design and construc-tion of dams and reservoirs. He has worked on over 50 dam and reservoir projects in his career. His expertise includes earth, concrete, and rock!ll dams and their foundations, and he has played a key role in the development of modern techniques in engineering geological investigations for dam foundations. He has extensive experience in slope stability of both natural and excavated rock and soil slopes. Typical slope stability projects range from design of excavated slopes for civil and mining projects to investigations and repair design of recent landslides.

John DunnicliffA consulting engineer, Mr Dunnicliff specialises in geotechnical instrumentation. He has taught more than 100 CPD courses on geotechnical instrumentation worldwide, and is author of the book Geotechnical Instrumentation for Monitoring Field Performance. Since 1984 he has been the editor of the North American maga-zine Geotechnical Instrumentation News (GIN), soliciting and editing articles and writing a column for each issue. In 2010 he was awarded Distinguished Membership of the American Society of Civil Engineers.

Mr. Joe EhaszMr Ehasz has over 45 years of experience in civil engineering, design and construction of dams, hydroelectric facilities, tunnels, and power plants. His major !eld of interest is in civil and geotechnical related aspects of water resources projects; in particular, the soil and rock

mechanics design, analysis and construction of earthworks and foundations for dams, embankments, and major civil works. He has achieved many extraordinary accomplishments in leadership roles of design engineer, chief engineer, construction manager and geotechni-cal engineer in worldwide water and power projects, notably Design Director, Senior Technical Review and Project Consulting Panel Member for the 200m, 395MW San Roque Multipurpose Project in the Philippines; and Project Construction Manager for the $800M, 32Oft high RCC Olivenhain Dam Emergency Water Storage Project in California, US.

Mr. Paulo Cezar Ferreira ErbistiMr Erbisti is the author of the important textbook, Design of Hydraulic Gates. Based on the authors extensive expertise and experience as an engineer of hydromechanical projects, this book describes the principal aspects of the design, manufacture, instal-lation and operation of hydraulic gates. This Brazilian engineer has contributed greatly to hydropower/dam engineering in the last 35 years in Brazil, Venezuela and in several other countries of the world due to his extensive consulting work. He has worked on a number of important project including Itaipu, Guri, Caruachi and Tocoma.

Prof. Dr.h.c. Michele FanelliMichele Fanelli has been active in the !eld of dam analysis and design for more than 50 years. He was among the !rst to advo-cate and promote the study, development and practical applica-tion of Finite Element numerical methods in Civil Engineering, with particular emphasis on concrete dam engineering. He has been involved in the design of several arch dams, including the 135m high Tsankov Kamak arch dam in Bulgaria. Now a private consultant he continues to inspire dam engineers with his experi-ence and expertise.

Brian Forbes Australia-based GHDs Manager for major dam projects, Mr Forbes has over 40 years of international experience in the inves-tigation, spillway modelling, design, documentation and construc-tion of all types of dams, with an international reputation for his expertise in RCC dams, having been closely involved in over 40 projects in 19 countries.

He is considered instrumental in the introduction of roller com-pacted concrete (RCC) for use in dams in Australia.

Desmond HartfordDuring his 30-year career in Canada, where he worked with BC Hydro and Klohn Crippen Consultants, and in Ireland, Mr Hartford has been developing the knowledge base and promoting new and modern approaches to the assessment and management of dam safety. He was one of the !rst in the dam engineering community to recognize that the risk-informed and systems-based approach can signi!cantly improve the decision-making process in dam safety. He is currently a leading authority on probabilistic risk assessment and management for dams.

He is the principal author of the textbook Risk and Uncertainty

WWW.WATERPOWERMAGAZINE.COM JANUARY 2011 23

DAM ENGINEERING

in Dam Safety and also a principal author of the International Commission on Large Dams (ICOLD) Bulletin on Risk Assessment in Dam Safety Management. He is also the author of numerous papers on the subject of probabilistic risk assessment for dams and broad issues of geotechnical engineering and soil mechanics.

Prof. Alfred Skip HendronProf Hendron works as consultant full-time on the design and construction of dams around the world with active projects in Africa, Southeast Asia, and South America and throughout North America. Most notably he is the primary consultant to the United States Federal Energy Regulatory Commission (FERC) which has regulatory authority over all non-federally owned hydroelectric dams in the US. In this role, he has direct and demanding in!uence over the design and construction of new dams and the remediation and re-build of existing dams that are under FERC jurisdiction. In recent years, this has included the Saluda Dam Remediation Project and the Taum Sauk Upper Reservoir Re-build and the Silver Lake Rebuild.

David E KleinerKleiner was the head of the geotechnical group in Harza Engineering in Chicago. In his position, he directed the design of many world class earth and rock"ll dams, including Yacyreta in Argentina; Guri and La Honda in Venezuela; San Roque in the Philippines; Cerron Grande and 15 de Septiembre in El Salvador; Bath County, Kinzua and Rocky Mountain in the US; THP in China; Mohale in Lesotho, and many others. He has also par-ticipated in many other dam projects reviewing and de"ning the foundation for the dam (Olivenhain and Mossyrock in the US for example), or as member of review boards or panel of experts (Toulnustouc in Canada, and others). He has also been a long time participant in USSD and ICOLD, presenting papers during ICOLD congresses, and participating in the technical committees, speci"cally the Materials for Embankment Dams Committee.

Dr. Harald KreuzerA swiss consulting engineer, Dr Kreuzer has participated in a number of international events and has also served on a number of panels worldwide, particularly concerning dam safety issues. His vast experi-ence and knowledge has made a great contribution in addressing dam safety issues in a number of countries, including Sri Lanka.

Dr. Giovanni LombardiDr Lombardi is a specialist in civil works and tunnel construction. A Swiss engineer, he has contributed signi"cantly to new theoretical developments in the "eld of civil engineering hydraulic structures, particularly arch dam design. A past president of the International Commission on Large Dams, he has in!uenced the construction of numerous structures throughout his engineering life.

Prof. Vahid Lot!Prof Lot" has 24 years academic experience and 22 years profes-sional experience in analysis of concrete dams. He was lead analyser and designer of seven large concrete dams and technical advisor for several concrete dams in Iran. His knowledge and abilities on "nite element, concrete dams, and !uid-structure interaction courses have inspired many Iranian students to pursue their future studies or career in dam engineering. He has been lecturer and/or supervisor of many of the best dam analysers in Iran. He has published more than 43 journal and 42 conference papers.

Bayardo Materon Mr Materon is the actual President of the CFRD International Society. He has participated in the design and construction of the worlds highest CFRDs, and has been involved with many leading engineering organisations on design and construction of rock"ll dams and hydro projects. He has been involved in numerous conferences and is author of hundreds of papers that have in!uenced dam engi-neers worldwide.

Dr. Paul C RizzoDr Paul C. Rizzo has made a tremendous impact in dam engineer-ing through his involvement with the Federal Energy Regulatory Commission (FERC), his dedication to numerous panels and committees, and his commitment to dam safety. He is an inter-nationally recognized expert in geotechnical, civil, and seismic engineering. He has more than 44 years of experience related to a wide range of projects including dams, waterfront facili-ties, pumped storage facilities, and power plant structures. As founder of Paul C. Rizzo Associates, Inc., Dr. Rizzo has built the "rm into one of the leading consultants in dam safety. In April 2010, the "rm completed the Taum Sauk Upper Reservoir Rebuild Project, for which it served as the Engineer of Record and Construction Manager.

Prof Dr Anton J SchleissCurrently Director of the Civil Engineering Department of the Ecole Polytechnique Federale De Lausanne (EPFL), Prof Schleiss has extensive experience in hydraulic engineering and underground waterways. He is involved as international expert in several dam and hydropower plant projects all over the world as well as !ood protection projects mainly in Switzerland.

Glenn TarboxGlenn Tarbox has 49 years of experience as a civil/structural engineer in all facets of water resource project development and management. Currently Vice President, Dams Practice Leader for MWH, he is an internationally recognized leader and expert in the design and construction of dams, with specialized expertise in con-crete dams. Tarbox has served as Design Engineer, Project Manager or Principal-In-Charge on more than 26 major projects in the US and throughout the world. He continues to be involved in RCC dams as Project Manager of the design review of Baise RCC Dam in China and Olivenhain RCC Dam. He was awarded the ASCE Opal Civil Engineering Award of Merit in 2005 and Milestone RCC Project 1987 to 2007 at the 5Th International Symposium on RCC Dams, Chairman ITR Committee for the USACE, and is currently lead designer for the 117-foot-high raising of San Vicente Dam in San Diego, California, using RCC technology. In his manage-ment role, he has in!uenced and mentored young engineers in the development of sound engineering practices and contributed to the development of dam engineering and dam safety practices.

Dr. Alexander TsengDr Tseng has a long, distinguished, multi-national career as an engi-neer, entrepreneur, educator and problem-solver that spans 60 years. He is founder and president of ORENCO (Oriental Engineering and Supply Company), a subsidiary of Tseng Enterprises in Palo Alto, California. Dr Tseng was the driving force behind the design and development of the self adjusting !ood control gates that have recently been deployed on over 200 major hydro projects in China. These gates are rapidly becoming the standard means in China to both raise the level of existing dams and create impoundment facili-ties on rivers at low cost.

Dr. Martin WielandDr Wieland has more than 38 years of experience in the analysis and design of complex civil engineering projects, and is a leading expert in the "elds of earthquake engineering and structural dynamics. He is the author of over 200 technical papers, and is a member of various interna-tional professional organizations, Chairman of the ICOLD Committee on Seismic Aspects of Dam Design, and Chairman of the earthquake committee of the Swiss Committee on Dams. One of his key qualities is his interest in gathering existing experiences and knowledge and dis-seminating this knowledge to other dam engineers.

To comment on this feature, or send suggestions for future listings, please email: carrieannstocks@

globaltrademedia.com

IWP& DC

24 JANUARY 2011 INTERNATIONAL WATER POWER & DAM CONSTRUCTION

TUNNELLING

AMONG the many tunnelling works being completed or getting underway in Latin America and Asia there are a selection of hydro projects that present a range of challenges through combinations of scale, layout and, of course, ground conditions.

In Chile, the La Con!uencia project is the upstream of a two-plant cascade scheme and its headrace system involves two long, divergent branch tunnels, each with multiple inlets, and the spread of bores have been excavated by drill and blast. Other projects in the country such as Angostura and Chacayes also have interesting tunnelling works.

Elsewhere in Latin America in Peru and Panama are further hydro tunnel challenges. In Peru, preparations are underway for Cheves project which calls for a wide variety of tunnel and cavern excavations. Then, in Panama, the Pando-Mont