Do-it-yourself

Rainwater recovery system: when it's convenient, pros and cons


There are many rainwater recovery systems, on the market there are models intended to be underground and systems capable of integrating with garden furniture, easier to install but which take up more space and have reduced storage capacity. Certainly those who live in a very rainy area can opt for oneplantrecovery to bury, while those looking for a system forrecover rainwaterintended to irrigate the small garden or vegetable garden, you can choose a surface model with a storage capacity of up to 350 liters.

To support the multiple models ofrainwater recovery systems, do-it-yourself systems exist. With the'rain waterrecoveredit is possible to perform different tasks, from the classic garden irrigation, up to the flushing of the toilet.

Thanks torainwater recovery systemsit is possible to clean the house and activate the washing machine. A big advantage of using therain waterfor toilets lies in its anti-limescale action: therain waterit does not favor the formation of limescale reducing the consumption of anti-limescale and thanks to the better cleaning action it also reduces the use of detergent, even halving it. In the field of irrigation, therain waterpromotes optimal absorption of minerals.

How to recover rainwater

To build arainwater recovery systemit is necessary to identify at least one of the building's rain drainage pipes and then convey it to the collection tank which, according to your needs, can be buried or integrated into the garden furniture.

The recovery pipes of thewaterwhile the various collateral for the re-distribution of therain water; in this regard, a distribution system for irrigation and a distribution system in the home may be necessary (to provide for the water needs of the toilet drain, washing machine, floor cleaning ...). The circuit created with thedo-it-yourselfit can be fed by natural fall or with pressure by means of a pump.

Rainwater recovery system: elements

A system ofrecovery of rainwaterit is usually composed of 4 elements:

  1. a collection area (in the most classic situation it is a roof)
  2. a convoy system (generally consisting of a gutter)
  3. a drainage duct leading therain waterrecovered
  4. a storage container which receives the recovered rainwater.

The classic gutters for the recovery of rainwaterthey are available in a variety of materials, the most common being galvanized steel, PVC or bamboo. One timerecovered, L'rain watercan be used for domestic use, for garden care, for toilets ... more rarely, therecovered rainwaterit is transformed into drinking water after undergoing further treatment.

Therecovery of rainwaterit stands as a solution to the increasingly probable and imminent water crisis in much of our planet. Rainwater recovery systems are relatively inexpensive and the whole principle can enjoy high efficiency, the only limit is imposed by the capacity of the storage tank and the collection surface.

There are a wide variety of tanks on the market: from underground to anchor-shaped ones to be placed near the walls of the house, near the gutter, like the one in the photo below.

Rainwater recovery system

When you want to take advantage of a gutter for the recovery of rainwater, some factors must be taken into account:
- Obstructing factors
- destructive factors

Trees, with seeds and leaves, can obstruct the conveyor system of the gutters while the roots of the tree risk damaging both the foundations and the lining of the underground tank causing cracks and leaks. A second consideration should be made keeping in mind the type of soil: it is better to bury the tank near a rocky, hard or compact ground. Hard ground will tend to limit the damage of any cracks by minimizing losses. Rocky ground can even shrink cracks, conversely, soft ground can expand them.

When it is convenient to build a rainwater recovery system

A system ofrecovery of rainwatermaximizes its effectiveness in areas where the amount of precipitation is between 100 and 500 mm per year. A study conducted by the Dutch CIR (International Research Center, The Netherlands) concluded that thecollection of rainwaterit is cheaper and more convenient where rainfall is between 100 and 500 mm per year. If the amount of precipitation exceeds 500 mm, the costs for installations and maintenance related torecoverywill outweigh the benefits, just as if the amount of precipitation is less than 100mm, the benefits could not cover the costs in a reasonable time.

Guide to building a rainwater recovery plant

There are several examples of plants to recover rainwater. Among the many I point out the one presented by the surveyor. Lino, on his personal website: http://web.tiscali.it/ik3ngu/acqua.html

where you will find an illustrated guide to build it.

A related article of ours that might interest you is the one on How to purify rainwater

Rainwater recovery plant, permits and incentives

The old 2008 budget - law 244/2007, article 1, paragraph 288 - has provided that from 2009 the issue of the building permit is subject not only to the energy certification of the building, but also to the structural characteristics of the water saving and the recovery and recycling of rainwater. Some regions have enacted more precise laws on the matter, such as Lombardy, Tuscany, Umbria, Puglia, Lazio and the Marches.

As for the tax concessions for the installation of arainwater recovery plantwe refer to the 2015 Stability Law which together with the restructuring bonus and the various Ecobonus, has introduced an ad hoc plan for those who intend to operate in the field of water saving.

Tax incentives for the purchase and installation of arainwater recovery plantrefer to Legislative Decree no. 83 of 22.6.2012 with Law no. 190 of 23 December 2014 (better known asstability law 2015). The incentives are provided in the form of tax deductions as described in the article dedicated to Eco-bonuses.

Advantages of an underground tank compared to a surface tank

The underground tanks, although more expensive than ground tanks, they do not cause any encumbrance and are protected from sunlight and thermal changes. With the underground tanks higher costs are mainly related to the installation of theplant.

With careful design of therainwater recovery system, it will be possible to reuse the water from the tank by exploiting the natural slope of the land in order to avoid the energy costs associated with the use of a pump.

the scheme of use of the Isea Riusa Plus rainwater recovery system

Video: Tools for the beginning DIYer - Power tools (October 2020).