6 November 2023

SOS drought: do not waste water, with plants for first rain water

The recent abnormal heat wave and drought this summer has dramatically highlighted the importance of treating water as a valuable resource. In this context, plants for the purification of first rain water emerge as a key element to avoid waste, and promote responsible management of water resources.


First rain water plants: what they are and how they work

First rain water treatment plants are rainwater collection system . These, once purified, are sent back to a collection basin from which they can then find a new use.

The “first rain”, in fact, that is the first 5 millimeters fallen in the first 15 minutes of precipitation (in some regions, the “first rain” is instead identified with the first 4 mm), is potentially the most polluted. In fact, it collects particles, dirt and micro-pollutants suspended in the air, or on the places of precipitation, usually aprons and parking lots. The first rain water, therefore, must be specially treated to reuse it without risk in the domestic and industrial environment, as well as for re-immissioning in the environment.

First rainfall plants, in short, contribute to an efficient and responsible management of water resources because in the first place they separate the first rain waters from the so-called second rain waters (less polluted). Then, they allow you to collect and treat them, sending them back to a suitable purification system.


Operation of a treatment plant for fresh water


Impianti Di Prima Pioggia In Polietilene

During precipitation, especially the most abundant, rainwater is collected in a drain with weir. Here, the waters of second rain, which touch the threshold of 4 or 5 millimeters, are immediately sent to the final delivery (except in some regions, which provide a special treatment for these). The first rainwater, however, is channeled into a subsequent treatment plant.

There are two types of plants for first rain water:

  • First rain plants in accumulation. In the first accumulation of rain, the first 4 or 5 millimetres of rainwater are collected in an underground or outdoor tank. Here, the rainwater has time to settle, to increase the effectiveness of the subsequent purification treatments which are relaunched (in the plants made by Di Camillo Serbatoi) after 48-96 hours by a timed pump.
  • Plants of first continuous rain. In systems of first continuous rain, the water is sent directly to the sanding chamber and then deoliazione already during the precipitation. It lacks, in short, a tank of first rain, which allows to separate the water from sand, soil and other sedimentable materials, which would accumulate on the bottom of the tank.

A Di Camillo first rain plant, therefore, also includes a sand removal chamber and a coalescence deoliator, sometimes also an oil-absorbing tank, to complete the purification treatment of first rain water, and thus allow its final discharge into surface water.


Advantages of a treatment plant for fresh water

In particular, for industrial sectors with high water consumption, plants for the treatment of first rain water represent an opportunity to save resources and reduce rising costs of water bills. Rainwater collected and treated can in fact be used as sanitary water, and for appliances such as washing machines, which will work better without the tap water limestone.

But rainwater collected and treated can be recycled in production plants, with systems independent of those of distribution of drinking water. Greenhouses, car washes, irrigation for farms in the agricultural sector… for your first rain water treatment plants, then, contact Di Camillo.

Since 1959, Di Camillo Serbatoi SRL has been a safe and reliable partner in the production of tanks and plants for the purification of water, including first rain water. Di Camillo provides you with innovative and customized solutions, as well as a wide range of services and accessories.