Professor, you are a hydraulic engineer, you teach at the Second University of Naples and you know well the flooding problems of the area north of Naples and south of Caserta. But why do these areas always flood after rains like yesterday's?
Because the hydraulic sewerage infrastructures of the territory you indicated are largely insufficient for the hydraulic protection of the territory. Unfortunately, the attention of the institutions for the hydraulic problems (and not only) of our area has been very low.
We have arrived at the current situation of serious widespread critical issues, which has been repeating itself for several years with varying intensity, also because there has been a lack of general direction on the management and control of supra-municipal hydraulic systems. 
Furthermore, large areas have been affected, in the last thirty years, by a large demographic expansion, also due to a strong phenomenon of illegal construction, later regularized with amnesties, which should have been followed, in an adequate manner, by the construction of a sewerage network sufficient to dispose of rain flows such as yesterday's. But, essentially, the hydraulic systems for land protection have remained the same as thirty years ago without even retaining the functionality they once had. 

In particular, are there enormous inconveniences on the coastal strip due to the maintenance of the canals? 
The coastal strip of Giugliano is an area particularly exposed to flooding phenomena, we remember that it is an area subject to numerous ancient reclamation works by the Consorzio di Bonifica Inferiore del Volturno. Therefore, the need for monitoring and control actions on the functioning of the infrastructure must be carried out continuously. Instead, many of these hydraulic works (such as the high, medium and low water channels) are no longer functional due to poor maintenance and, in fact, are largely blocked by the flow of rainwater. In many cases, the canals were also blocked by illegal works. Furthermore, there are problems also linked to the insufficiency of the existing sewerage networks which do not reach all areas of the coastal strip and, in many situations, are undersized.
There are still problems linked to building design errors, especially with reference to underground or semi-underground floors where adequate lifting systems, non-return valves, optimal arrangement of uncovered areas and periodic maintenance of drains are lacking.
Finally, in the coastal area, there is also a delay in completing the doubling of the lifting system in Via Madonna del Pantano, the construction of which is currently at a standstill due to technical-administrative problems, which will have to be resolved as a priority and which could contribute to alleviating the critical flooding issues of recent days.

Even the Marano area close to the Camaldolesi often suffers extensive damage... What can you tell us about it?
The Marano area is, in some ways, even more critical than that of the coastal strip of Giugliano. The ancient natural riverbeds that conveyed the waters of the Camaldoli hill have, in several cases, been filled up and connected in systems not adequately sized for the current meteoric flows. Furthermore, the action of capturing and infiltrating rainwater into vegetal soils has been greatly reduced by the intense urbanization which has paved over, making large agricultural areas waterproof. This phenomenon has made the existing sewerage infrastructure largely insufficient, including the Camaldoli riverbed which now reaches maximum capacity levels even for rainfall of intensity and duration like that of last October 10th.

Among the most affected is the area of ​​via Verdi and dei Monaci in Giugliano; Is the cause due to the fact that the old cable is no longer there? 
The problem is mainly linked to the insufficiency of the sewerage collector built below Via Santa Caterina da Siena into which huge flows come from Via Cumana and Via Verdi which, in turn, connect huge flows of the basins flowing upstream which correspond to large city hydraulic sub-systems. Also in this case, compared to when there was the ancient "open-air cavone" behind the Monks' convent, the green areas of Giugliano have been intensely waterproofed due to the strong building growth of the city and, evidently, the works carried out to guarantee the correct disposal of the flow were not adequately sized.

The Appia has become a river and yet it is a road that should withstand such calamities... 
The Appia is a true urban paradox: a road of such importance as a crossroads between several large municipalities (Melito, Aversa, Sant'Antimo and Giugliano) as well as one of the main junctions of the Median Axis does not have, as we have understood correctly, a sewerage system for collecting and collecting rainwater and, therefore, the river that is generated is inevitable. However, there is an executive project created by MetroCampania in agreement with the neighboring municipalities, partly completed but not in operation, which would completely solve the problem by also fixing the roadway, sidewalks and lighting. The project involves the construction of large collectors that start from the Giugliano metro station and discharge onto the Appia in a large collector that already exists at the height of the church of the Evangelists on the Appia. The project is stopped due to lack of regional funds.

What should the institutions do to prevent these phenomena? 
Lots of things! Unfortunately, even on the hydraulic protection front (as well as on waste and environmental emergencies), the institutions have great responsibilities. It is advisable to refunctionalize the systems by adapting them to the current rain flows, regularly clean the channels and ducts, guarantee periodic control actions. In short, do all those things for which we contribute, as citizens, to pay the many municipal, provincial and regional institutions responsible for monitoring, managing and controlling the territory as best as possible. 
In particular, it is necessary to accelerate ongoing projects... As in the case of the sewerage project on the Via Appia or the doubling of the lifting system in Via Madonna del Pantano, where the institutions know perfectly well the problems that need to be addressed as soon as possible by resolving the technical-administrative slowdowns and finding adequate economic resources to complete the works. Also for other situations, such as via Verdi, the Camaldoli area of ​​Marano, the canals of the coastal strip, etc. there are several feasibility studies and projects that require extraordinary intervention by the Campania Region to allocate resources, complete the project phases, flag the tenders and carry out the works. In short, it will take a few years and a lot of money but the solutions exist and it is necessary to find them as soon as possible.

And what can we do in the meantime?
In the meantime, the relevant institutions must limit possible damage by improving the maintenance of the collectors, the periodic cleaning of the drains, the search for leaks to prevent the collapse of the collectors which involves the waste of further economic resources (we have seen recent testimonies in the historic center of Giugliano in recent months). 
For the citizens of the most exposed areas, hoping that the institutions resolve the many hydraulic problems in the shortest possible time, I recommend that they equip themselves with small hydraulic and building measures to limit the risk and damage deriving from meteoric flows and help monitor the state of the canals and hydraulic works by promptly reporting it to the relevant municipalities.

(from interview given to TeleclubItalia)