Ensuring good water quality is a major challenge for seaside resorts. The quality of the water is vital to the smooth running of water sports activities (swimming, surfing, sailing, etc.). If the water is of poor quality, bathing areas can be closed to avoid any health risk to users.
Introduction
In France, the monitoring of bathing water quality is governed by a European directive. The aim of the regulations introduced in Europe is to obtain good quality water in order to protect the health of bathers and users of the sea.
Samples are taken from June to September by the ARS (Regional Health Agencies) or laboratories, and are used to classify bathing areas according to their quality. It is therefore important that the bathing water is of good quality to ensure that the area remains attractive.
A challenge for seaside resorts
In order to classify each beach and inform coastal users about water quality, samples must be takenat least 4 times during the summer season. However, in some regions, such as the Pyrénées-Atlantiques,samples are taken on a weekly basis. The aim is to detect the presence of two bacteria: Escherichia coli and intestinal enterococci, which are the main indicators of bacteriological pollution of the water. If too many of either of these bacteria are detected, bathing is banned to protect the health of bathers. Bacteriological pollution can lead to skin reactions and ENT and digestive problems.
The Basque coast has built its image on water sports and surfing in particular. Unlike bathing, water sports are practised all year round on generally different spots. However, the sampling required by law is not carried out outside the summer period, and only concerns bathing areas
To remedy this problem, Surfrider Foundation Europe carries out additional samplingthroughout the year in the Basque, Breton and Mediterranean water sports areas. These measurements are used to regularly (twice a month) inform users about the quality of the water in which they are swimming and to highlight any water pollution problems that may bepresent.
Water quality on the Basque coast
Several factors make the Basque coast a particularly sensitive environment for pollution.
– Extensive coastal urbanisation and a large influx of tourists
The Basque coast is very attractive during the summer months. Biarritz, for example, sees its population rise from 25,000 to 110,000. This influx of tourists means a considerable increase in the volume of water to be treated.
– Water treatment infrastructures not adapted to the summer period
The Basque region is prone to severe bad weather: between 140 and 150 days of rain a year on average, and heavy storms. When a sewage network is combined, i.e. rainwater and wastewater are collected in the same pipes, the volume of water to be treated by the treatment plants is greater. As their storage capacity is often limited, storm overflows can be used to store excess water.
– Several consequences
When the volumes of water to be treated exceed the network’s treatment and storage capacities, they are discharged via storm overflows into the natural environment (ocean and rivers) so as not to damage the pipes, which could burst in the event of overloading.
It is as a result of these occasional spills that bathing areas may be closed. These measures are applied to avoid any health risk to users.
