The stream of life

The Maltese islands have very few permanent freshwater streams.

Found on the west side of Malta and in Gozo, these streams are an important habitat to a number of species and plants.

These streams occur in places where the clay is still intact. The Maltese islands are made up of five layers of sedimentary rocks. Rain water can percolate through all these layers except clay. 

In areas where no clay is present rain water percolates through the rock strata until it reaches sea level and forms a layer on top of salty water. This is the water that is extracted through boreholes and galleries for domestic and commercial use.

In areas with a layer of clay percolating water is unable to continue moving down as clay does not allow water to pass through it. The water on top of the clay moves horizontally until it finds a way out, usually a fisure in the rocks and here it forms a stream.

At Baħrija Valley we find one of the most important fresh water streams in the Maltese islands. It provides habitat for the rare fresh water crab, which is known in Maltese as qabru, a species that requires water throughout the year. 

It is an important species in need of protection. Its conservation is of utmost importance because the local race is endemic to the Maltese islands, that is, it is not found anywhere else in the world.  

It is already legally protected and nobody can pick it up or kill it but what is required is more protection of the fresh water habitat where it lives. 

The water must be allowed to flow and any form of pollution, especially by pesticides and herbicides must be strictly controlled. 

This article was published in The Times on 1.08.2012.