UNITED NATIONS ECONOMIC COMMISSION FOR ASIA AND THE FAR EAST FLOOD CONTROL JOURNAL ST/ECAFE/SER.C/15 June 1953 C 0 N T E N T S Page I. HAVOC WROUGHT BYFLOODS DURING 1952 3 A. The typhoons 3 B. The floods 8 II. PROJECTS OF THE REGION 16 A. Aerial surveys for Ceylon projects 18 B. The Pykara and Moyar Power Development Schemes, India 19 C. Tapi Valley Development, India 27 D, Aerial survey of Pakistan's natural resources 35 E. Two-Year Priority Programme, Pakistan 37 F. Philippines Hydro Programme 37 III. PROJECTS OUTSIDE THE REGION 44 A. The Snowy Mountains Project, Australia 44 B. Plans for Egypt's Nile re-vamp life-giving river 48 C. Californian Water Conservation Project 49 D. Earthfill dam in the tropics 50 E. Flood prevention in Hungary 51 /IV BENEFIT CENSUS - 2 - Page IV. BENEFIT CENSUS OF MULTIPLE-PURPOSE PROJECTS 52 V. ARTIFICIAL RAINFALL 57 a. Increasing water resources through modification of weather 57 B. Demands for Rain-making service seen increasing 60 C. Rain-making projects aid Washington foresters 60 VI. NEWS OF INTEREST 61 A. Conciliation of high versus low dam issue 61 B. Road sprinklers for canals and dikes 62 c. Grouting stops Arizona dam leakage 64 D. Engineers to direct flood operations from helicopters 64 VII. RIVER INTAKES - A REVIEW 65 - 3 - I. HAVOC WROUGHT BY FLOODS DURING 1952 A. the TYPHOONS Floods, occurring in countries of Asia and the Far East, are caused generally by heavy precipitation brought about by cyclones (typhoons) during the south-west monsoons period. For a study of floods devastating a particular area, an examination of the cyclones which visit such an area is therefore very helpful. The cyclones that develop in the region of Asia and the Far East are of two types - extra-tropical and tropical. The latter ones are of particular importance as cyclones of tropical origin occur more frequently in Asia than in any other part of the world, particularly in the China Sea region. The tropical cyclones generally originate on the ocean east of the Philippines and south of latitude 20°N. They move westward and later continue to move westward or turn north or north-east. Some of the cyclones developed have a parabolic path, swinging to the north. These occur during the summer months of June to September and are responsible for flood flows of the Luzon rivers when they sweep across the Philippine Islands. Some of them move into the South China area during July and August and cause heavy precipitation in the Pearl river basin. Those which swing to the north and cross Japan are responsible for the floods in the Japanese islands. The Pacific cyclones which move westward across Indochina, Thailand and Burma, sometimes re-develop over the Bay of Bengal, and continue to move westward over India, particularly during periods of well established east winds prevailing in the upper air from July to October. Of cyclones striking the coast of the Indochinese peninsula, a little less than 40 per cent finally progress westward over India. In the Bay of Bengal, besides those coming from the China Sea, cyclones usually develop over the southern section of the Bay, following generally a northern path, but some move in a westerly direction. Maximum frequency of occurrence takes place as the summer monsoon retreats while the air masses are unstable. The heavy precipitation of this tropical disturbance during the southwest monsoon season contributes to the floods of the rivers of the / Ganga system, Ganga system, as well as of others. Figures 1 and 2, prepared from data supplied by the Meteorological Department, Royal Thai Navy, Bangkok, and the India Meteorological Department1/ show the movement of typhoons in Asia and the Far East during the year 1952. Figure 1 shows that there were no typhoons in this region during the period January to April 1952. A depression developed at 87˚ E and 13˚ N in the Bay of Bengal on 19 May 1952. This depression travelled eastwards till 21 May, when it turned north­ west striking the east Coast of India as a typhoon travelling towards Vaizaga- patam. On 10 June 1952, a. typhoon was observed at 116 °E and 16°N between the Macclesfield and the Paracels islands in the China Sea, rising north-north-west, turning north-west on 11 June, towards Kwang Chow Wan (China coast) on 13 June and then abruptly turning north-east towards Kanchow (China) on 15 June. On 20 June another typhoon, known as typhoon Dinah, started from near Virac in the Philippines, went up almost northwards till 22 June near Ishigake Shimo, island and then turned north-eastwards, going past the east coast of Japan on 24 June. The heavy damage done by this typhoon is described in the text below. A third typho n started from the Bay of Bengal on 25 June and travelled north-east, all along as a depression, towards Agra (India), working havoc in its wake in Assam, Bihar and Uttar Pradesh in India and in East Bengal in Pakistan. On 1 July, the typhoon Emma started almost half-way between the Yap Island and Surigao in the Philippines, crossed the Philippines between 2 and 3 July causing severe damage, rose north-west, reached Julien on 6 July and rose further north inside China. A depression started at 19°N and 89°E in the Bay of Bengal, rose north-west, struck Kharagpur on 4 July as typhoon. This typhoon was the cause of the rising of rivers in Bihar. Then the typhoon crossed over towards Kotah, Central India. Another one was onobserved 18 July at Ishigaki Shima Island east of Taiwan, moved north-west and then further north towards Shanghai on 20 July. Damage was done by this typhoon in Taiwan. A third typhoon started on 28 July, causing damage in the north of the Philippines and went straight north-west, reaching east of Canton on 30 July. /In August 1/ These two diagrams have been prepared from data specially prepared by the Meteorological Department of the Royal Thai Navy and the India Meteorological Department for the Bureau of Flood Control of the Economic Commission for Asia and the Far East. TYPHOON DEPRESSION LOCATION OF TYPHOON May AT 0700 HOURS (LOCAL TIME) JUNE JULY AUGUST KAREN - LUIS 5 - FIGURE 1: TRACK OF TYPHONS, JANUARY-AUGUST, 1952 TYPHOON DEPRESSION LOCATION OF TYPHOON AT O7OO HOURS (LOCAL TIME) SEPTEMBER OCTOBER NOVEMBER DECEMBER FIGURE 2: TRACK OF TYPHOONS SEPTEMBER-DECEMBER, 1952. - 7 - In August, two important typhoons started from almost the same place, 130 °D and 16˚N. The typhoon Karen Started on 13 August, went north-north-west up to the island of Nahe on 15 August reached Shanghai on 17 August, then turned north-east and reached Saishu-To on 18 August. The other one, known as typhoon Luis, started on 25 August westwards, crossing as a depression over the Philippines, reached Vientiane (Laos) on 29 August and finally crossed the northern part of Thailand. Figure 2 shows the typhoons from September to December. Typhoon Mary started on 1 September at Keshun, reaching Foochow on 2 September and going eastwards as a depression on 3 September towards Akita. This typhoon caused damage in Taiwan. A second typhoon started at 129˚ E and 12˚ N, crossed over the Philippines the same day, went westwards over Hainan on 6 September and reached Indochina on 8 September. third one originated near Paracels island on 17 September and crossing Hainan, also reached Indochina and northern Thailand on 19 September. This typhoon was all the time a depression, A depression started on 17 October near Capiz (Philippines), travelled westward, became typhoon Vae on 20 October at Nha Trang (Viet-Nam), on 22 October crossed Indochina and Thailand where it caused considerable damage in Nakorn Phatorn and went up north-west along the western coast of Burma as a depression. Typhoon Trix started on 20 October, crossed the Philippines on 22 October and crossing the China Sea, reached Indochina on 25 October, proceeding further as a depression. The typhoon Wilma started on 26 October, crossed the Philippines on 27 October, bringing heavy damage to the islands, and then reached Tourane (Viet- Nam) on 30 October. The typhoon Agnes started on 4 November. A depression developed on 8 November at 87°E and 15°N in the Bay of Bengal, turned north-east as a typhoon on 9 November and struck Noakhali East Bengal, Pakistan on 11 November . The typhoon Bess developed on 11 November and Carmen on 18 November. Another typhoon started on 23 November from 128°E and 12°N as a depression, became the typhoon Della on 24 November. A depression also started at 89°E and 8°N in the Bay of Bengal on 27 November striking the southern corner of India as a typhoon on 30 November. A depression started on 9 December from 110°E and 8°N and went north-east. /The typhoon - 8 - The typhoon Gloria started on 20 December, crossed the Philippines and went towards Indochina. B. THE FLOODS 1. Burma The typhoon Vae passed on to the southern coast of Burma towards Rangoon on 23 and 24 October. 2. Ceylon In Ceylon, towards the end of May, moderate to heavy rain was reported from several stations chiefly inland. The Kelani Ganga was 10 1/2 inches above the minor flood level of 5 feet. The low-lying areas of Sedawatte, Kohilewatte and Ambatalenpahale were gradually experiencing a minor flood. With the heavy rains in the hills, the flood authorities expected the possibility of the Kelani waters rising to 7 feet.