Runoff Volume Reduction Using Green Infrastructure

Abstract

Uncontrolled urbanization is a frequent cause behind the local flooding of catchment areas. This also results in a degradation of water quality in receivers, as well as causing a disruption of the natural water cycle in the catchment. Classical solutions, such as retention, do not prove to be sufficient under all conditions. An alternative solution is the application of low impact development (LID), which, in the analysed case, takes the form of rain gardens, infiltration trenches and controlled unsealing of catchment components. The work presents the influence of a few variants of solutions on a selected urbanized catchment located in Gorzów Wielkopolski. The assessment was developed using a simulation model, making use of EPA’s Storm Water Management Model (SWMM) software. The nalysed design variants are compared with the described existing state before the implementation of modernization works. Previous results showing that LID may be ineffective as the only solution in systems overloaded with runoff generated by rainfall of relatively low intensities were confirmed. In the case of existing systems, LID should be applied in combination with classical retention systems or in a treatment train and every opportunity to implement LID whether on a property or urban site must be taken. Such solutions in the analysed cases will allow for a reduction of the maximum outflow intensity from the analysed subcatchment by 9 to 17% depending on the analysed rainfall. The results are similar to those obtained in other implementations. However, the interpretation of the results is not as simple and obvious for overloaded systems. In addition to flow rate reduction, reduction of surcharge in the sewer network and reduction of the volume of local flooding must be considered. LID solutions should also, whenever possible, be looked into as early as the stage of planning the land development of the infrastructure.

Evaluation of the Influence of Catchment Parameters on the Required Size of a Stormwater Infiltration Facility

“…The application of modern methods for designing stormwater infiltration systems, including hydrodynamic modeling, is limited to devices located directly at the site of rainfall, the so-called LID facilities, whose task is to reduce stormwater runoff from the catchment area [45]. However, research indicates that the best solution is to use LID elements together with more classical methods that allow, for example, the retention of stormwater [46]. Unfortunately, in a case of facilities dedicated to stormwater infiltration with retention, where stormwater is delivered through a system of interconnected channels, the use of hydrodynamic modeling is rare.…”

Influence of storms on the emission of pollutants from sewage into waters

“…An alternative solution is to reduce stormwater inflow to the sewer system by infiltration in infiltration basins, collection for later use and other techniques such as Low Impact Development (LID) 42 or Sustainable urban drainage systems (SUDS) 42 . The analyses performed so far indicate that the synchronous use of LID techniques with classical solutions such as retention in tanks or retention in sewers [41][42][43][44][45] is optimal.…”

A New Method for Selecting the Geometry of Systems for Surface Infiltration of Stormwater with Retention

“…The implementation of devices such as rain gardens or drainage wells is generally considered the easiest way to manage stormwater [30]. However, studies [31] indicate that the best results are achieved by using LID facilities together with more classical solutions, such as stormwater retention. This was also confirmed by other studies carried out in Central Europe [27,32], according to which one of the most beneficial ways of managing stormwater is its surface infiltration with retention.…”