Due to the changing climate, it does not necessarily rain anymore, but it does rain more heavily in short periods. Showers with an intensity of 40mm precipitation per hour are no longer exceptional and are increasingly common. The graph below indicates that this picture has changed, with the exception of a rainfall of 76mm per hour in 2011. Terms such as recurrence time will be discussed later.
When we consider that the average sewer in the Netherlands has a capacity to process 20mm of water per hour, the problem is clear. The sewers are overloaded by the heavy rainfall, whereby a logical solution would be to relieve the sewer by infiltrating into the soil or rainwater infiltration.
Rainwater infiltration means that the rainwater (rainwater) that falls is absorbed by the soil. A fairly logical principle, but due to buildings and surfacing, rainwater cannot enter the soil in many cases because it is hardened due to roads, roofs or terraces, for example. Rainwater that falls on roofs is traditionally supplied to the sewer through the rainwater drainage. Water that falls on the public road runs into the sewer through wells (gullies). Water that falls on a terrace can also run into the sewer through a gutter, or one chooses, for example, to run the terrace down to an alley where the water still reaches the sewer. In any case, in many cases it does not end up on the soil where it can infiltrate locally and sink into the soil, which is actually the natural way.
RWBNL offers solutions in rainwater management using the products of Hydrorock. In addition to being a dealer of these products, RWBNL is also specialized in the installation of these infiltration / drainage solutions within all sectors and has a network of gardeners who can make use of the knowledge of RWBNL and obtain advice. In addition, they can also offer the product to customers and place it if desired.
Hydrorock is an ecologically sound infiltration block that can absorb 94% of its volume in water and slowly release it to the soil. The blocks use 5-sided infiltration, which gives the highest yield compared to other products. In concrete terms, this means that less m3 usually needs to be buried and therefore less earthwork is required. The blocks are supplied in various sizes and volumes. There are blocks from 34 liters to 440 liters. Large buffers can be created by connecting these blocks by means of a coupling tube or by laying them against each other. The blocks are extremely suitable for processing under, for example, street work. Due to the slim shape of the blocks (30 or 40cm) wide, it is sufficient to dig a trench through which the blocks can be placed. Ideal in existing situations where, for example, there is little space.
The infiltration blocks can be used to disconnect rainwater drains from roofs or other pavements such as parking lots or terraces. Line gutters of terraces can be installed effortlessly without the need for piping. Special line channels have been developed which can easily be placed on the blocks. In addition, the blocks can also be used as drainage in poorly drained soils and can be used to keep the soil moist during dry periods.
For more information, go to www.rwbnl.nl