An analysis of some of the parameters affecting rates 'of heave has been made on a digital computer. This indicates that the shape of the rate-of-heave curve depends to a considerable extent on the initial moisture conditions and the type of soil. Provided the moisture flow beneath the centre of the structure is one dimensional and upward during heave, the time taken for 90 per cent of full heave to occur depends only upon the coefficient of swell Cs' This coefficient can be determined in the laboratory from a modified consolidometer test. Alternatively, it can be estimated from indicator tests.
The whole range of parameters which should be taken into account to maximize the benefits from the water yield of the catchment area were enumerated and a forward-looking philosophy stated which requires close co-operation between many disciplines and maximum use of the tools and devices now available for rapid selection and implementation of projects.