At the end of June, there is an annual mass swim across the lake from Torno to Moltrasio organised by Moltrasio’s Rowing Club.

Each year we publish the data on the cleanliness of the water across the twenty two beaches or lidos on the Como leg of Lake Como. The official collection of data starts mid to late April so the results quoted below are from last year’s season (2023). Out of the 22 sites tested, 2 had no data for unknown reasons, one was deemed ‘good’ and the remaining 19 were classified as ‘excellent’ for swimming. These results provide a resoundingly positive reply to those questioning if Lake Como is safe for swimming. Details are reported below.

The EU’s Bathing Water Directive

Go to portaleacque.salute.gov.it to access the latest data on the level of bacteria in water sampled from Lake Como’s beaches

All the countries within the European Union apply the standards defined in the 2006 Bathing Water Directive. These require member states to monitor rivers, lakes  and beaches regularly, to report their results and immediately publicise closure whenever any specific location fails to achieve acceptable levels. There is a broad range of poisonous bacteria that can enter the water either from sewage, water treatment centres or as agricultural or industrial run-off. Beyond causing gastroenteritis, they may also lead to very serious conditions such as meningitis. Rather than test for the wide variety of possible bacteria, the tests focus on identifying the number of units of just two microorganisms, e-coli and intestinal enterococci. Levels of these provide a good indication of general levels for the other harmful bacteria. Units are measured per one hundred millitres with any number below 1000 acceptable for e-coli and below 500 for enterococci. Depending on results, the water from each site is then classified as being either excellent, good, sufficient or poor.

Water Temperature

Como Nuoto used to organise a competitive swimming race across the lake. Let’s hope it is reinstated now that the fate of the swimming club is more secure.

The Lake Como swimming season runs from June to September. During these summer months, the average temperature of the surface water on the lake does not fall below 20°C.  The actual average summer temperature of the water is 23.2°C with June at 21.3°C, July at 24.1°C, August 24.2°C and September at 20.4°C. In contrast the winter average is a mere 5.8°C and currently (April) it stands at a bracing 13°C. 

Lidos and Beaches

The lido at Faggeto Lario pictured off season in uncharacteristically high wind.

Those not familiar with Lake Como may be initially surprised at what is defined as a beach here, particularly if they have the seaside in mind where beaches are often more extensive areas of pebble or sand. While there are more open areas of beach to the north of the lake, with accompanying facilities and water sports, the southern end is more rugged with mountains regularly running down to the water edge. So any flat, sandy or grass area on the lakeside could be given the sobriquet ‘spiaggia’. However only those beaches with at least the bare minimum of services are included in the water quality monitoring programme. This does not mean that the ‘unofficial’ beaches are any less clean. In fact, since they are more likely to be away from the larger areas of population, they can safely be assumed to share the general high level of water  cleanliness found elsewhere.

The ‘spiaggia’ or beach at Careno, just below the romanesque church of San Martino. This beach is not monitored for water quality but is located between two of the cleanest monitored beaches on the lake.

Lidos provide more services in exchange for an entry fee. All offer sunbeds and  umbrellas with a bar service. Most also include changing cabins and showers. Although some occupy quite a small area, e.g. the lido at Faggetto Lario, they offer an experience similar to their seaside equivalents. 

The Data

The lido in Viale Geno

The table below shows the figures for the two lidos in Como – Villa Olmo and Villa Geno – for the tests done over the swimming season (June to September).  Colour has been added to the row for the tests done on 28th August because the results are anomalous being much higher than all the other tests done but still within the levels deemed acceptable for swimming. Most other sites on the lake also recorded higher figures for that week in August probably due to levels of rainfall beyond the capacity of the local purification plants to manage entirely satisfactorily.  When such weather events occur, the impact on water quality is worse close to the larger centres of population such as Como.

The Winners

The beach at the tip of Bellagio is the second cleanest on the Como leg of the lake.

As mentioned previously, there are no losers last year in that all beaches sustained results within acceptable levels of bacteria across the whole season BUT there are winners. 

By totalling the figures in the two columns across the five testing dates per location, we have devised a simple ranking of beaches with the best achieving the lowest overall score. The top three places all go to beaches on the eastern side of the Como leg of the lake. The overall winner is Rosina beach in Nesso, very closely followed by the Spartivento beach in Bellagio. Third place is shared by the lido in Faggetto Lario and the Salice beach in Lezzeno. So the very cleanest beaches are all on the Bellagio side of the lake. 

Detailed figures for these four winners are shown in the table below.

Note here how figures for testing on the 28th August are higher than the average but not to the same extent as in Como itself. 

Lenno’s lido is the cleanest on the western shores of the Como leg of the lake.

The cleanest beach on the western shores of the lake was at Lenno Lido (5th in overall ranking), followed by Cernobbio Villa Erba. Then came Tremezzina Parco Teresio, Colonno Lido and Sala Comacina. Argegno Lido is next but this has a swimming pool for those not wishing to bathe directly in the lake. Moltrasio follows. This beach was closed last year and recently bought by the Hotel Imperiale who will reopen it again this season. The last two in the list are Laglio Tenclu and Ossuccio Ospedaletto. This latter beach is in a truly delightful location facing on to the northern shores of Isola Comacina. But its results are nothing like as impressive as most others with an E-Coli reading for August almost tipping the unacceptable level at 850 units per 100ml.

The lido at Ossuccio. This is a delightful setting and the water is within acceptable bacterial limits but it does come at the bottom of our crude system of ranking.

This table shows the ranking of all the beaches and lidos tested in our area. The figures in the right hand column are simply the sum of all the data collected over the five occasions during the swimming season. For the details, please go to the Portale Acqua site.

Conclusion

Overall wild swimmers can feel confident in finding clean water in Lake Como if entering the lake at any of the listed public beaches and lidos.  There are a number of locations where swimming is actually prohibited. This is either because the location is close to the outlet of a purification plant, such as in the tempting beach area behind the Tempio Voltiano in Como, or because it is near a landing stage for boats. The lake does not suffer from any significant chemical pollution since most of the land on the surrounding mountain sides is not cultivated and bacterial pollution is kept well under control as year on year data goes to show.

The beach area behind the Tempio Voltiano is NOT a permitted swimming site since it is at the mouth of the Cosia river and just downstream from the city’s waste water purification plant. It does look very tempting on a hot sunny day but it is not safe.