September_1966 — Page 67

1 circuit for sub-station auxiliaries. 3 local circuits.

1 bus coupler.

Mahang Reservoir

Water discharged from the three turbines will be led through a 16 ft. diameter 5,000 ft. long tailrace tunnel (designed to run full) and will be im- pounded in a regulating basin (Ma- hang Reservoir of 350 acre-ft. capa- city) formed by the construction of the Mahang dam. This dam, again of rolled earth fill construction, will be 50 ft. high and will contain 150,- 000 cu. yd. of earth fill,

Water will then be led through three reinforced concrete culverts em- bedded in the Mahang dam to the Odak power station and finally dis- charged into the Batang Padang River. Provision will be made for a rein- forced concrete bellmouth spillway which can discharge a maximum flow of 1,200 cusecs.

Odak Power Station

This will be a surface power station, housing three 1,400 kW Francis water- wheel driven alternators feeding into the 11 KV bus at Woh switchyard.

Access Roads

A total of 18 miles of 8 ft. wide tarmacadam access roads leading to the various sidestream intakes, tunnel adits, etc., will have to be constructed.

Location of these roads on steep side- long jungle-covered slopes has not been an easy task.

Consultants

The consulting engineers to the National Electricity Board are Preece, Cardew & Rider, London, in associa- tion with Binnie & Partners, London. The Board's Project Engineer is Mr. P.G.D. Shallow, MA. MICE, MIWE.

Contractors

Contract No. 1 B Switchgear

Allmanna Svenska Electriska Aktiebolaget-Sweden (A.S.E.A.) Contract No. 2 Transformers

Savigliano, Italy. Contract No. 6 Civil engineering works

Hochtief-Holzmann, Germany. Contract No. 8 Control gates

Glenfield & Kennedy, Scotland. Contract No. 9 Mechanical and electrical plant Woh power station

Fuji Electric Co., Japan. Contract No. 10 Mechanical and electrical plant Odak power station

Şalzgitter, Germany. Contract No. 11 Cables

not yet awarded.

Subcontractors

Under contract No. 6 Penstock pipes

—

Voost, Austria.

L

Penstock prepacked concrete

Intrusion Prepakt (Far East) Ltd., Hong Kong.

Site exploration, cut-off grouting

etc.

Cementation Ltd., London. Dams, Odak P.S.

Kien Huat Ltd., Kuala Lumpur. Engineers' housing and offices Boon & Cheah Ltd.,

Kuala Lumpur.

Access roads

Liew Ling, Ipoh.

Sidestream intakes

Chop Wah Lee Construction Co., Cameron Highlands.

Under contract No. 9

Erection of plant

Overseas Construction Co., Japan.

Supply of cranes

Nippon Crane Works, Japan. Supply of inlet pipes

Sakai Iron Works, Japan.

Acknowledgement

The author wishes to express his thanks to Y.M. Raja Zainal JMN, MIE (FM), General Manager, Na- tional Electricity Board, for permis- sion to write this article, and to the three resident engineers, Mr. D.E. Cox, BSc (Eng), AMICE, Mr. P.C. Sadler, BSc (Eng), MICE, and Mr. M.V. Seewer, for their help in its preparation.

Weir and stilling basin for the Odak power station tailrace basin spillway. Embanking for Mahang Dam in progress beyond;

three of the five culverts passing through the dam can be seen

Far East Architect & Builder September, 1966

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