Naples:life,death &
                Miracle contact: Jeff Matthews

entry May 2010

the Naples sewer system

Me & the Grand Poo-Bah of Cuma

I apologize to Gilbert & Sullivan fans. My guy is not really a Poo-Bah. In fact, he is not even a he. He is an it, called in Italian, Il Grande Emissario di Cuma. Far from being some Magna Greek potentate sitting with Sybil on Mt. Cuma and directing trireme traffic below, my Emissary is simply something that emits. In this case, Il Grande Emissario di Cuma is better translated as the Large Cuma Effluent —or, the Big Sewer. And if I had known all that some years ago when I went swimming at Cuma, I might not have done so.

Like most good surface dwellers, I have no interest in my business once it leaves the porcelain. I trust in the robots and human Warlocks down below to carry it all peacefully to the sea, where omnipotent Mother Nature will take care of it, as overworked as that poor woman seems to be. (Currently, she is helping out British Petroleum.)

This, then, is about the Naples sewers: the woes and triumphs and very difficult task of clearing this large metropolitan area of human waste.

Until the unification of Italy in 1861, Naples had a system that was generally as adequate as that of most cities of comparable size in Europe (c. 500,000). We should remember, however, that in spite of accounts of running water and flush systems even in parts of the ancient world, what we commonly call "modern plumbing" did not exist in cities in Europe or America until the mid-to-late 19th century. Cities that had no sewers relied on rain to wash away sewage. If the city was near a river or the sea, that helped. In many cases, however, waste water ran down the streets and eventually drained as runoff into the local watershed, a disaster when you think that cholera and typhoid are water-borne diseases.

The sewer system in the Naples of the 1860s was the one put in place by the previous, pre-unity government, the Bourbon rulers of the Kingdom of the Two Sicilies. It was a "mixed" system of 54 collectors totaling 180 km in length set at various points in the city. ("Mixed" means that the lines carried both waste and rain run-off, unlike modern systems, which now segregate the two.) The collectors channeled sewage down to the shoreline of the city and out to sea, where it was dispersed. In those days, sewage was channeled into the sea untreated. (Chemical treatment plants came in around 1900 in most places).

Fresh water is essential, of course, and even before the modern aqueduct system, Naples usually had a good supply. The aquifer beneath the city is abundant, and even the old aqueduct system was good. (A new aqueduct, the Serino, was built in 1881-85. There is a separate entry on the aqueduct.) Most large dwellings were directly tapped into the aqueduct through a vast series of underground chambers and even the poorer classes had access to wells and fountains from which to draw water. Yet, the great deficiency of the sewer system in Naples at that time was its inability to deal with overcrowding in the so-called bassi, the low areas of town. Between 1873 and 1883 there were studies of the extremely precarious conditions of public hygiene in the city. Cholera broke out in 1884 (Axel Munthe's personal account of the epidemic is here). It was frightful and was the proximate cause of the decision by the Italian government to tear down large portions of the city and rebuild them. That project was called the Risanamento. It lasted 25 years and included designing and building a new sewerage system.

Work began in 1889. The basic plan was:

Free the local city shoreline from sewage and channel it into a single collection (affluent) line that would start at Piedigrotta in the western part of the city, run west and empty just outside the Gulf of Naples at a single large effluent on the shoreline below Mt. Cuma.

Channel rainwater, however, into the waters along the urban shoreline via a new system of channels (thus, the introduction of modern dual-channel conduits);

Regulate rain run-off in the hill areas.

For 25 years, while new buildings were going up and new streets were being laid, the workers on the sewage front juggled affluents, effluents, pipes, collectors, drains, elevation pumps, skimmers, filters, maintenance access shafts, and so forth. By 1915, it was finished —a modern system. It was good and served well for a number of years. The city of Naples, however, incorporated a number of surrounding communities in the 1920s. That and, especially, the helter-skelter expansion of the city after WWII led to a situation where, by 1950, the system had to meet the needs not just of normal population growth, but growth within an area four times greater than the one originally planned for.

In 1949, a new study was commissioned to rebuild the system. The Cassa del Mezzogiorno (the national Monetary Fund for the South) kicked out the impressive sum of L. 22,322,900,000 [sic!] for the job. Strings of numbers like that should be illegal, but that figure in Italian lira (L.) equaled about 36 million US dollars in the early 1950s, when the project was funded. Comparative purchasing power is more complicated to calculate, but most indices indicate that 36 million $US in the early 1950s equals very roughly at least 300 million $US in today’s terms, i.e. 2010.

New work was essentially a modernization of the old 1915 network plus expansion to include the areas incorporated in the 1920s; these extended from San Giovanni and the industrial areas in the east all the way through the towns of Fuorigrotta, Bagnoli, Soccavo and Pianura in the west, stopping short of Pozzuoli, almost all the way to the Cuma effluent, itself. As well, the extensions included all of the Vomero and Posillipo communities, which were mere villages in the 1880s. (By way of comparison, the ex-village of Vomero is now the most heavily populated in Naples in terms both of absolute population and population density thanks to the advent of modern high-rise construction techniques.) The entire shoreline on the south, as well, was modernized, including the industrial and civilian ports.

Most of that work was finished by the 1970s. As well, the aqueducts were upgraded to supply the increasing needs of the city. There are now four main lines that supply water from sources in Lazio, Molise and Campania. Besides the 1885 aqueduct, there now exist the Campania aqueduct (1958), the Western Campania aqueduct (1998) and the Lufrano Aqueduct.

The good news (among all this very difficult work to upgrade the city) has to do with population. The 1967 report, cited below, contains this:

...[water supply]...will increase with the completion of the Campano aqueduct to about 350 liters per person per day (including the amounts provided by existing aqueducts) for a population of 1,425,000, predicted by the year 2000...the calculations run through to the year 2020 and aim at a sufficient water supply for the predicted population of 1,650,000.

That figure is way off. The current population of Naples is just under one million, somewhat less than in 1951! According to the predictions, Naples should have around 1,500,000 at this writing (2010). What happened? Well, it is true that increased mobility since the 1950s has made it easier for people simply to live outside the city limits. That has happened in Naples as it has happened elsewhere, so that affects the numbers a bit. The real factor, however, is growth rate. The professors with the crystal balls in 1967 predicted growth based on a figure of about 0.7%. A population growth rate of 1% will double a population in 70 years, so the one million figure for Naples in 1951, at somewhat less than one percent growth—0.7%—would give us a steady rise; indeed, the population in Naples hit about 1,200,000 in 1972, so the prediction seemed on track. Then, however, the bottom fell out of the growth rate; the Pill and the concept of Zero Population Growth had arrived in Europe. A growth rate of 0.7% is much higher than most places in Europe have right now. The population growth in Italy, in general, is less than zero at the moment and a smidgen above zero in the south. The figure of 0.7% was somewhat of a worst-case scenario, and it didn't happen.

So, the Grand Poo-Bah's job is a bit easier.


Most of this information comes from Il sottosuoli di Napoli [The Subsoil of Naples], commissioned and published by the city of Naples in 1967. As of Oct. 2019, the complete report published in English on the NUg (Napoli Underground website is no longer on-line. It is now, however, in the pages of this Naples: Life, Death & Miracles website, here.

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