Toward a policy consensus in the recovery of rainwater

The Big enclosure Via, of Fira of Barcelona, received the technical day ‘Aprovechamiento of pluvial waters in edificación'. In the frame of the fair Construmat 2011, celebrated this session organised by Aqua Spain, organisation that groups to more than 130 companies of the water, in which it gave to know the ‘Technical Guide of Aprovechamiento of Pluvial Waters in buildings'. In words of María Strip Pastor, vice-president of Aqua Spain, the meeting posed like “forum of debate that expect serve to enrich the document guides that we present here”. For this, it would be necessary to follow the example of other more advanced “countries”, like Germany, where have several norms DIN about how work and manage the pluvial waters. “Our final aim would be to realizar a complete work, from all the possible points of view, that gave place to a rule or legislation that complete what already apply nowadays, those city councils with ordenanzas specific about these waters”, argued the vice-president of Aqua Spain.

With the purpose to promote the recovery of water of rain, to finals of the year 2008 and to instances of a request of the Agència Catalan of l'Aigua, summoned to a series of entes related with the pluvial waters, between which appeared Aqua Spain. After two intense “years” of work, the commission of Management of pluvial waters presented this technical document, around the middle of May, that analyses the existent technological solutions, applicable to the needs of some Mediterranean surroundings in matter of aprovechamiento of the pluvial waters in buildings. The presentation pretended to put to disposal of the society and of the public organisms this initial “document”, as it defined it the vice-president of Aqua Spain, for like this contribute, to a sustainable management of the resources hídricos alternative. The meeting, headed to proyectistas, architects, consultores, engineers, technicians of the administration, installers and distributors, for example, had the assistance of a cincuentena of people, between representatives and technicians from institutions, public organisms and companies of the sector.

The round of reports of this day initiated with the intervention of Laia Núñez, technician of the department of Planning and Supply of the Agència Catalan of l'Aigua (ACA), the one who detailed the administrative frame and technician of the recovery of pluvial waters. Basically, the spokesman of the ACA detailed where fit the pluvial waters inside the hydrological organisation, as well as the lines of action that undertake from the Agency. Like context, did reference to the approval of the Plan of Management of the Water in Catalonia, the past year, in reply to the requests of the Directive Mark of the Water (2000/60/CE), by which the water no longer contemplates only like a resource and considers integral part of an ecosystem. This European Directive urges to the States member, of face to the year 2015, to obtain a good ecological state of the masses of water. In consequence, the Plan of Management of the Water in Catalonia has of a program of measures that details all the investments and performances that will contribute to attain this good ecological state of the masses of water and also, to guarantee the supply of this resource, so much in quantity as in quality, to the current and future population.

According to this Directive, all the performances of the Hydrological Plan have to be directed to obtain water and take care the ecosystems, for like this ensure the future supply of the same. To end to satisfy this increasing demand, contemplate new technologies like the desalación, reuse of waters debugged, improvement of the efficiency of the networks, exploitation of aquifers, and finally the saving of water, in himself same. In this field, from the ACA reward to all that that wish to install a deposit of aprovechamiento of pluvial water of domestic use, so that it does not have to pay the canon of the water derived of the consumption of this deposit. “It is a measure that tries to promote the utilisation of these infrastructures of aprovechamiento. Although it is true that for aprovechamientos underneath of the 7.000 cubic metres to the year, has to communicate to the Agència Catalan of l'Aigua. For aprovechamientos upper would have to ask a granting of water”, puntualizó. Likewise, the Plan of Management of the Water in Catalonia includes a normative chapter that does reference to the pluvial waters. In this sense, and thinking in possible subventions, values the existence of ordenanzas of saving of water and that these, comport the obligation for houses with more than 200 square metres of garden that take advantage of pluvial and grey waters, so that they obtain a higher bonus. “It is the first introduction of the pluvial term in a hydrological plan, thing that up to now there was not sucedido in Catalonia”, ensured.

From the ACA, in collaboration with the technical commissions of Aqua Spain and some public organisms like the Deputation of Barcelona and the Departament of Sanitat of the Government of Catalonia, follow working with the purpose to establish technical criteria regarding design of systems of aprovechamiento of pluvial and also sanitary ware. To date, they have detected a series of flaquezas in the ordenanzas of the 46 Catalan municipalities that have an applicable rule to the pluvial waters. “These weak spots arise of the fact that each one of the ordenanzas used a distinct method of calculation for the deposits of aprovechamiento of waters of rain. From the ACA have initiated a technical work with which want to facilitate the task of the city councils to the hour to establish some criteria for the dimensionado of the deposits. For this, have elaborated some abacuses in function of diverse zones of the Catalan territory, adapted to the climatology”. Through these abacuses, interpolan diverse variables, like the surface of the roof, or the equivalent of lawn and can determine the minimum volume that would have the deposit.

For its part, Irene Corbella, Salut environmental of Agència of protection of the health area, focused more on the health aspects of rainwater. A resource which defined it as "an almost pure water in origin,." from the health point of view Only when it falls it absorbs minimum trace amounts of metals, especially in urban areas. "Later it can deteriorate during the collection and storage in the points of use". The rapporteur also stopped to enumerate the main sources of pollution. As the runoff from roofs, which rain water can collect leaves, fecal droppings of birds, insects or other animals. The degree of contamination increases if the surface runoff and even according to the surface where rainwater is collected. For example, contamination of rainwater for road transit detects the presence of oils, metals or hydrocarbons. "However, improper cleaning of deposits can be another source of contamination." "Rain water is of good quality, involves little maintenance but something must be done to avoid the risk, and they can be prevented." He then referred to the lack of normative regulation, and that there was no European directive on sanitary quality of rainwater and nor expected the adoption of any legislation at State, regional or local level to regulate this matter. Then, Jochen Scheerer, Coordinator of the Committee of management of rainwater in Aqua Spain, focused his intervention in the 'Guide technique of utilization of storm water in buildings', protagonist of the day. To this end, it back to the use of rainwater in the country of fashion from the 1980s. During his speech, he tried to disassemble topical as "in Spain not it rains" and stressed that climate change condition a best or worst rainfall utilization. "Rain is a good business for the sector." "Well treated it contains fewer organisms in the washing machine to the clothes that we are going to wash".