Profitability Analysis of Selected Low Impact Development Methods for Decentralised Rainwater Management: A Case Study from Lublin Region, Poland

Abstract

Water scarcity affects at least 11% of the population and 17% of the territory of the European Union. Simultaneously in cities there is a problem of urban floods caused by violent and intense rainfalls. Decentralized drainage systems are designed to capture rainwater runoff at the place of precipitation and improve the hydrological conditions through the use of surface and subsurface infiltration, retention, and evapotranspiration techniques. The purpose of this paper was to evaluate the financial profitability of selected Low Impact Development (LID) methods for decentralized management of rainwater disposed from the roofs of two different buildings. In the presented conditions, the use of dual installations and infiltration tunnels turned out to be cost-effective solutions, whereas infiltration boxes were unprofitable for both buildings. The most unprofitable solution would become profitable if the investment costs were reduced by as much as 67% or if it was possible to generate 2.28 times more benefits. Although the research was carried out for specific conditions, the obtained results may be helpful in the implementation of similar investments. They are also a kind of contribution to the assessment of the cost-effectiveness of LID on a global scale due to the universality of the proposed research methodology.