The water of Nice's spectacular Baie des Anges is monitored weekly from June to September. If you head to the beach early you may see the small boat that takes water samples about 10 metres from the shore. The samples are then tested for E-coli, total coliforms and streptococci. The results are posted at www.nice.fr.
So much for the invisible dirt. What about floating bottles, plastic bags and other unsightly detritus? Niçois call it the "Courant Ligure" (Ligurian current) and it brings 20 tons of detritus each year. You won't see much of it though. That too, is regularly swept up by the four cleaning boats that patrol the waters from June to September.
If you watch the water regularly, as I do, you'll notice that it's visibly cleaner in the morning. That's because the nighttime currents regularly sweep any detritus out to sea.
You'll also notice that the water is visibly cloudier after a storm as water purification stations in the region overflow into the Paillon river which dumps its effluents into the sea. Many Nice residents avoid swimming for a day or two after a storm.
All 27 Nice beaches meet EU minimum standards and 26 are categorised as "good quality". The one "medium quality" beach is Centenaire which is closest to where the Paillon river meets the sea.
Blue Flag Beaches
The Blue Flag program is a program run by the non-profit organisation, the Foundation for Environmental Education (FEE). The idea is to promote sustainable development of beaches by awarding a "blue flag" to beaches that meet standards of water quality, environmental education and management, safety and other criteria.