Sand in Portugal is an ubiquitous granular substance which is a basic resource material used in all manner of manufacture ranging from glass utensils to electronic equipment. It is found in a variety of natural colours and its consistency can be altered by the addition of clay, oils and resins when used, for example, in moulds for the casting of metals.
In the construction industry the standard mix for concrete is one part cement, two parts sand and four parts aggregates . It is also an essential ingredient for asphalt, paint, football pitches, golf courses and foundation material for pathways
Supplies of sand have been obtained largely by dredging river estuaries and beaches while a small amount of M-sand has been produced artificially by the crushing of rocks. Inland formations of sand ridges mark the courses of former waterways . They vary in size from a few hundred metres to several kilometres and generally provide groundwater aquifers which support vegetation such as eucalyptus and cypress pine.
Until mid 20th century the mining of sand for this vast range of uses did not present a great environmental problem but the explosion of demand caused by the population movement to coastal locations and the expansion of associated commerce and industry has presented growing threats to a coastline which has always had a history of erosion.
Consultation of ancient maps and admiralty charts shows that one third of Portugal´s 648 km coast has been critically affected during the sixty year period to 2010 with retreats of the highwater line ranging from 0.5 to 9.0 metres a year and amounting to an overall loss of 1,313 hectares. The region of Caparica has been one of the worst affected with the destruction of water-edge buildings and agricultural land . Much of this loss can be attributed to tidal currents and a prevailing north westerly wind which have overcome revetments, promenades and other erected barriers
But since 2010 the immediate dangers caused by changes in climate have become obvious. Rising sea levels, alterations in the intensity and direction of prevailing winds, the threat of underwater volcanic activity and resultant tsunamis will all combine to alter the movement of sediments and thus the characteristics of our beaches , cliffs and harbours. It is therefore vital that restrictions should be introduced which will curtail new construction in coastal regions but encourage the rehabilitation of older buildings for occupation principally by Portuguese citizens (especially in the neglected interior) thus forming part of a stabilised and eventually reduced but stalwart population which will preserve its Portugality.