Storage, quality and use of rainwater after a "green" roof

Abstract

The issue of reuse of natural resources occupies an important place in resource conservation, environmental friendliness and reduction of the man-made load of construction around the world. The use of water resources is of particular importance. They are a strategic, vitally important natural resource, the national wealth of every country, one of the natural foundations of its economic development. In addition to reasonable consumption, it is necessary to promote the preservation, restoration and reuse of water resources. One of the many methods of effective and at the same time the most natural management of water resources is "green" constructions. These are biotechnological means that combine building structures and living plants. This paper examines the implementation and creation of "green" roofs for the collection, accumulation and re-use of rainwater. The chemical composition of water after passing through the "green" roof, as well as ordinary rainwater from the roof of the building of the residential complex "Respublika" was analyzed. Water sampling was carried out in December 2021 during rainfall. It is shown that the concentration of impurities in wastewater from "green roofs" does not exceed the permissible values for drinking water. In addition, financial costs for the construction of conventional and "green" roofs were presented. Additional costs for the creation of a "green" roof will be 20.89% of the total cost of materials and 63.49% of the total cost of works for the construction of a stationary roof. Means for reuse of rainwater on "green" roofs are considered. It is shown that thanks to the retention of water by the layers of the "green" roof with an area of 490 m2, it is enough to provide a tank with a volume of 150...250 dm3. Data on the volume of used water for technical needs (irrigation) from Faina-Town residential complex in Kyiv are provided. It is shown that the accumulated rainwater is sufficient to meet the needs for watering the adjacent territory.