The Mar Menor is Spain’s largest saltwater lagoon. It is separated from the Mediterranean Sea by La Manga and four towns border it; Cartagena, Los Alcázares, San Javier and San Pedro del Pinatar. For decades it has attracted tourists and visitors due to its warm, clear water.

But the Mar Menor has a fragile ecological system, one that environmentalists have warned is at risk for the last eighteen years. In 2013 scientists from the Spanish Institute of Oceanography monitored the contaminants entering the Mar Menor via the rambla at Alabujón and they found 70 different types of pollutant.

Now, it looks as though their unheeded warnings have proved to be true. Most noticeable, over the past two years the Mar Menor has turned from a clear blue lagoon into what some have described as thick pea soup. Martin Hutchinson, environmentalist, was recently in Torrevieja as part of his tour around Europe, drawing attention to environmental problems. The contamination and destruction of the Mar Menor is now on his agenda.

The green appearance of the lagoon is caused by algae, phytoplankton, the growth of which is preventing sunlight from reaching the bed. Without sunlight, the reeds on the bottom of the lagoon cannot survive. It has been reported that 85% of the vegetation on the lagoon bed has now died.

The ecologist organisation ANSE and the national oceanographic institution have investigated what’s going on there. They discovered that vast amounts of vegetation have been wiped outand you can see the result of this on YouTube.

The difference between the bottom of the Mar Menor in 2014 and 2016 is astonishing. Whereas video footage shows that in 2014 the seabed was still full of plant life, in 2016, it is a completely different picture with very little plant life or coverage of any kind at all.

What’s to blame?

The prime culprit would seem to be the pesticides which have found their way into the lagoon from local farmland through the ramblas. The pollutants are a mixture of insecticides in the summer and herbicides in the winter. This is not the only reason, however.

The Mar Menor is a saltwater lagoon whose ecosystem is highly sensitive. Salt water is being filtered by local farmers to irrigate the land and the brine solution along with chemical fertilisers then finds its way into the lagoon through the ramblas. Excessive building and the tourist industry have also destroyed some of the natural processes which have kept the Mar Menor such an attraction over the years. During his tour, Martin Hutchinson interviews different people, some of whom suggest that attempts to rid the area of jellyfish have also taken their toll on the local ecological balance.

What can be done?

There are now actions taking place to address some of the issues, including a green filter being placed on the Rambla del Albujón. However, environmental groups believe that there are a number of additional issues that need to be addressed.


There are calls for intensive agriculture,which is being blamed for the pesticides,to be stopped. Environmentalists have also asked for building projects to be halted and port activity to stop in order to allow the currents to flow naturally and restore some of the balance that’s been lost.

There is growing anger too at local governments, who have been accused of turning a blind eye to the impending disaster, ignoring the warnings of the environmentalists. Whoever and whatever is to blame, it’s evident that drastic action must be taken to help restore the natural balance that once existed here and to restore the Mar Menor to its previous beauty.