Design of Water Storages, Etc (continued)

The entry of the Bureau into the field of hydrometeorology was not regarded as appropriate by many of the Commonwealth and State water authorities although the SMHEA and the WRP welcomed our initiative. The Australian Academy of Science had also shown interest in hydrology by establishing a National Committee to study the subject and the CSIRO had also established a group in Canberra to work in this field.

Gerry O'Mahony had been involved with the staff of the SMHEA in Cooma and at one stage after his return from his year at ANU Gerry and I visited Cooma to discuss their problems with Eric Kraus, whom we shall meet again under the heading of cloud seeding. Our trip in a wartime jeep through the Snowy Mountains was a memorable experience, Eric was a delightful guide who had been recruited as resident meteorologist with SMHEA after a period of working for Taffy Bowen in the CSIRO Division of Radiophysics. Allan Rainbird was later seconded to SMHEA from September 1960 to August 1961 when Eric Kraus was granted a year's leave of absence to study at Woods Hole Oceanographic Institution in the US.

The water authorities and research workers associated with design of water storages, drainage systems and flood mitigation required an accurate and complete description of the frequency distribution of the depth-area-duration of rainfall. The requirement for information on depth (amount) of rainfall and its duration ranged from an assessment of the duration of low rainfalls (to see if a storage would be economically viable) to an assessment of the duration of extremely high rainfalls (to see what size of drainage channels and dam walls would be required). In some cases a balance needed to be struck by risk of high rainfalls and cost of construction so that a design might envisage occasional flooding (once in twenty years) as acceptable. In other cases (such as construction of earth-fill dams) spillway design was required to provide for the maximum possible rainfall.

Bureau of Meteorology