RANDENIGALA PROJECT construction of a 94 m (308 ft.) tunnel, which along, with another high, 458 m (1,590 ft.) rock-fill similar tunnel is presently used to The Randenigala Project is the last across Mahaweli , creating a reservoir divert the river during construction of ofj the Major Multipurpose Projects of 860 million cu.m. (697,000ac. ft.) the dam. undertaken in the Accelerated Maha­ By July 1985 70 metres of the dam weli Programme. It consists of two had been completed and there was Randenigala Civil Contractors at .Randenigala and Rantembe. a further 24 metres to go. The power (RCC), a joint venture of the three Randenigala is due to provide the house on the Left bank immediately construction firms Dycherhoff & largest reservoir under the Mahaweli down stream of the dam will have an Widermann, Bilfinger & Berger, and Programme, and is located 6 km (3.5 installed capacity of 126 MW. A steel Alfred Kunz of the Federal Republic miles) upstream of Minipe anicut from lined 6.2 m (20 ft.) diameter, 270 of Germany was awarded the Civil where the new main Right Bank and m (886 ft.) long tunnel through the Works contract which is the main the old left Bank canals take oof for dam will convey water to the Power component of the project. The Civil irrigation development down-stream. House to run the turbines located just Contractor mobilised at site in early This project is expected to generate below the dam. The gated chute spill­ September 1982. The site installation about 20 percent of the country's way is 48 m (761 ft.) long and is works such as access roads, temporary present annual electrical energy re­ capable of discharging the probable bridges, houses, offices, electricity and quirement and will act as the most im­ maximum flood of 8085 cumecs water supply were completed in 1983. portant base reservoir for the water (285,500 cusecs). management of System C and B and later System A and transbasin By the end of June 1984, rock The irrigation outlet will be areas. and soil excavation for Diversion through a 9.6 m (31.5 ft.) diameter. Outlets, Approach Channels, Intake The Project chiefly consists of the 375 m (1,230 ft.) long concrete lined Structures as well as the drilling of the -ably, revised and by June 1979 the Construction costs continued to esca­ two diversion. tunnels and concrete total cost of the headworks was late and by 1982 the new estimate lining of Tunnel No. 1 were com­ estimated to cost Rs. 6,000 million. prepared was as fo I lows: pleted. Excavation work for Power Intake and Waterways and the Power House and most of the First stage Costs of Headworks - Kotmale concreting were also done. Estimated Contract Absolute Contract Price Price including June 1979 price variation Construction work for Power In­ (Rupees Million) take and Waterways, Spillway and Dam Embankment continued upto 1. Work done by government agencies (for 500 800 the end of 1985. All civil works are surveys, rehabilitation, communications. due to be completed by 1986. establishment and consultants) The hydro-mechanical, mechani­ 2. Civil, Works - cal and electrical works are being co­ Initial Works 681 ordinated according to the progress Underground Works 1,214 of the civil works and commissioning Reservoir 2,187 4,082 6,122 of the Project is scheduled for mid 1986. 3. Hydraulic equipment — Tunnel steel linings 46 : Tunnel gates, etc. 56 Spillway gates 90 Reservoir Impounding i Bottom outlet 75 267 438 Randenigala reservoir will have • 4. | Generating Plant - a surface area of 23.5 sq. km. (5,807 '. 292 acres) but will inundate only 2.8 sq. 1 Sub-station 152 444 739 km. (692 acres) of cultivated land. The population within the reservoir 481 5. Physical contingencies 321 area is only about 2,000 and of them nearly 300 have been re-settled in i TOTAL 5,614 8,580 System C.

Economic Review July/August, 1985 31 PROJECT BENEFITS CS OF RANDENIGALA ROCK FILL DAM 8 POWER HOUSE

Irrigation

The Randenigala reservoir will regulate the water release of the Victoria reservoir and will provide supplemental irrigation benefits to Systems A, B and C, with the sub­ sequent development of new Systems in the overall Mahaweli Programme.

Power Filter Actual rocki ^Sj line of canyon Transition The Randenigala power station Longitudinal Section of Randenigala power house will generate 428 GWH of firm energy and 100 GWH of secondary energy.

Employment

Over 2,000 Sri Lankans are being provided employment during the con­ struction phase. The project began Temporary with 125 expatriates and the number access is reported to be pruned down for to penstock replacement by local engineers.

Cost Estimates

The originally estimated cost of the Randenigala Dam and hydro­ electric unit was Rs. 700 million, engineer stated: "the finest opportu­ contractors for the construction of including a foreign component of nity to train and develop the en­ Randenigala Headworks are the Joint Rs. 350 million; the allocation for. gineering skills were offered by the Venture of Messrs. Dykerhoff Wider- irrigation being Rs. 415 million implementation of the AMP to this mann, Belfinger & Berger and Alfred and for power Rs. 285 million. country, but that opportunity was Kunz. missed. Feasibility studies for Randenigala and Rantembe projects were carried Australia's Snowy Mountains Pro­ out by "Joint — Venture Randenigala" ject did exactly that - they made the Consultants, comprising Messrs. Salz- best use of opportunity offered. We Rantembe gitter Agrarund Electrowatt assisted only helped the big consultants from by CECB, with a Technical Assistance abroad. We could have provided Rantembe Dam will be taken grant of D.M. 8.5 million provided by 100's of engineers and other technical up later about 3 km. downstream of the Federal Republic of Germany, skills by getting closer involved in the Randenigala, below the confluence of (through Kreditanstalt fur Wideraufban project." For a further elaboration of the Uma Oya with the Mahaweli - "KFW"). This was followed by a this viewpoint see comments of Prof. Ganga. It will be a concrete gravity long term soft loan of DM 400 million Thurairajah on page 34. dam 41.5 m high with a crest length from "KFW" for the construction of The total cost of this complex of 420 m (total volume of concrete the Civil Engineering Components. amounts to DM 400 million (foreign) being 215,000 cubic metres). plus Rs. 822 million (local) making There are views expressed among a total of Rs. 4.450 million. Hydro- The spillway will have 4 Taintor local engineers that the nature of the power will be developed with ah Gates 16.21 m x 16.0 m. with chutes contracts for the headworks generally installed capacity of 122 MW to 16 m. wide and 50 m. long capable of limited opportunities for them to generate 525 Megawatt hours of a maximum discharge of 10,235 m^/ benefit from these schemes. As one energy (average) annually. The Main sec.

32 Economic Review July/August, 1985 There will be 2 bottom (Irri­ SYSTEMS CAPABILITY WITH gation) outlets provided with Taintor VICTORIA, KOTMALE AND RANDENIGALA gates each capable of a maximum discharge of 200 m3/sec.

Steel Penstocks of dia. 4.2 m. with a rated discharge of 90 m3/ sec lead to the power station equipped with 2 Francis Turbines with an installed capacity of 24.5 MW each working under a gross head of 33.5 m. This will produce 158 GWH of firm energy annually (average 251 GWH).

The Federal Republic of Germany has provided financial assistance for this project of DM 400 million on easy terms. This was considered enough for the Headworks of Randeinigala and Rantembe Projects, but due to price escalation this was sufficient only for Randenigala at present costs.

The Minister of Finance declared recently that the Federal Republic of Germany has already agreed in principle to give a concessional aid in a sum of DM 120 million for the Rantembe Project. This amounts to 1978 1979 1980 1981 1982 19B3 1984 1985 1986 1987 1988 1989 1990 1991 1992 YEAR" approximtely Rupees 1050 million Source! Implementation Strategy Study NEDECO at % percent interest over 50 years. I EX • Existing system including 50 ltd thermal SOU • Bouatema am confident that the balance money CAN • Canyon also for the Rantembe Project can be NT Neu thermal — •Systems capability obtained very soon. Rantember is a Thermal generation corollary to Randenigala "I am confi­ Hydro generation dent that we will be able to commence - -—• Hydro generation uithout Kotmale, Victoria and Randenigala this Rantembe Project this year", he Operation and Maintenance of said. * Routine maintenance checks of Headworks embankment slopes and crests of earth embankments for evidence Upper Kotmale Hydro Power The Mahaweli Authority of Sri of the development of unfavour­ Lanka and its project heads, the able conditions. An agreement covering a feasibility , the Maha­ study of the Upper-Kotmale hydro- weli Economic Agency, the Maha­ * Detailed inspections of concrete power scheme was signed between the weli Engineering and Construction structures by operating personnel Japanese government and 's Agency, the Irrigation Department at yearly intervals, or more fre­ Power and Energy Ministry on August and the Mahaweli Water Management quently. A more thorough in­ 10,1985. Secretarial will all be responsible for spection by a board of engineers specific functions of operation and for important structures. maintenance on the reservoirs, tunnels, hydro power plants, dams, channels, The proposed project includes * Concrete-lined canals to be drainage systems and other irrigation the construction of one reservoir and dewatered periodically and in­ works and structures that have been two hyro-power generation stations spected for cracks and ruptures. wjth a total generation capacity of 230 constructed at such heavy cost. There MW. The study will take about 2 years is no doubt that great care would need * Radial gate offtakes sluices, lifting and the final report is scheduled to be to be exercised over these structures stems and gear also need constant submitted to both governments in once the construction is over. Among attention and a high degree of August 1987. the functions requiring emphasis are: maintenance.

Economic Review July/August, 1985 33 HOW LOCAL ENGINEERS COULD HAVE BENEFITED FROM MAHAWELI CONSTRUCTION

Prof. A. Thurairajah of the Open University, Faculty of Engineering

In the Accelerated Mahaweli Project, a number of large and complicated engineering structures such as reservoirs, double curvature concrete dams, rockflll dams, tunnels, underground power houses etc. have been constructed. The consultants and contractors involved in these projects are foreign companies from the aid giving countries. The design and construction of these structures would have increased and developed the technical capabilities of the personnel associated with these projects. One subject of interest to Sri Lanka and its engineering profession is how much of this advanced technology really got transferred to the Sri Lankans. Will our engineers be able to design and con­ struct such structures in the future ?

In meetings of engineers, it has often been mentioned about the famous Snowy Mountain Project in Australia which gave an excellent opportunity to the Australian personnel to obtain valuable experience in such works. With the training they obtained in those works, the Australians were able to Installation of equipment BY Local Engineers at Victoria Power House handle similar future projects without the competent? Hence, in an agreement with help of foreign technologists. The question these aid giving countries, we must ensure In the case of the Accelerated Maha­ now is whether this has happened in Sri that the Sri Lankans participate to the weli Scheme, we do not believe that a trans­ Lanka; or would we need foreign con­ maximum possible, thus increasing the fer of technology took place which in­ sultants and contractors if we have to technical capability of our personnel. creased the technological capabilities of our undertake similar |Obs in the future? p.fl'sonnel. We doubt whether our technical people gained the valuable experience from An earlier case comes to my mind in these projects so that they could now this connection. For the construction of a undertake similar projects locally or in other large factory, it was proposed to the aid- Technical capabilites of our personnel countries. One feels that what took place giving agency by Sri Lanka that all site will develop if we undertake jobs of this was the transfer of engineering structures investigation works and recommendation of nature by ourselves wherever possible and rather than the transfer of technology. It is suitable foundations will be undertaken by bring foreign consultants to advise us in a pity that Sri Lankan technical personnel a group consisting of the State Departments fields where we are not competent. This is have missed this unique opportunity of and University. But the aid-giving agency how even foreign companies operate. For gaining such valuable experience. On the visited our organisations and finally said example, the contractor for the double other hand had we obtained experience in that they could not accept this group doing curvature concrete arch dam at Victoria, all these works, we would now be able to the work since they had not done similar Balfour Beatty Nuttal, had not constructed form a consortium and bid for civil en­ work for another large factory before. After such a dam before. However, they hired a gineering works of this nature in other Third much negotiations, the aid-giving agency Swiss company to advise them on this World countries with success. It is also finally agreed to a compromise solution project. Now they can quote the Victoria sad to note that the Faculties of Engineering where the investigation, testing and pre­ experience to get jobs of this nature. had not been associated with these great paration of the report was carried out jointly in Sri Lanka by the group and a engineering works. The staff of the En­ It is a fact that aid giving countries are foreign firm. This arrangement increased gineering Faculties would have gained very anxious to give the consultancy and con­ the experience of the Sri Lanka personnel, valuable experience had they been involved tract work to companies associated with so that at least for any further job of this in these projects and this experience would their country. Therefore, even in cases nature, they will be able to satisfy the aid- have been very useful in the training of where we have the technical capability, they giving agency about their experience. In future engineers. At least in the future tell us that they cannot entrust the work to fact, when further work had to be carried we must provide the means by which a Sri Lankan agency since it has not done out at the site, where the site had to be pre­ the teachers of engineering can be asso­ such work earlier. Often this is true. But if loaded and settlements monitored, the ciated with important projects of this we allow this, when are we going to be able entire work was handed to Sri Lankan nature. to tell the aid-giving country that we have personnel. done similar jobs earlier and are therefore

34 Economic Review July/August, 1985