ABSTRACT
Canals have two important characteristics which, although also common to other civil works, are fundamental. One of them is that they are linear works, of great length, and so they
cross soils of diverse categories, sometimes with very different problems that require different local solutions, even having to use cross sections of different shape or dimensions for the canal, adjusting them to the circumstances of each case. The other fundamental characteristic is that the cost of the work depends
in great measure on the adjustment of the work to the field (topography, geotechnics, appropriate selection of machinery, etc.), and so the previous studies, final design and construction should be intimately related. It is evident that for the study of the layout of the canal the readiness of
appropriate topographical plans, supplemented by frequent detailed visits to the site by technical personnel, is essential.
