Environmentally friendly buffering and infiltration

Effective buffering and infiltration is easy with our Type D Hydrorock units. This type of Hydrorock infiltration blocks buffer and drain rainwater in an environmentally friendly way. The blocks ensure gradual infiltration to the surrounding soil. By installing the infiltration units, a water buffer is created that considerably reduces the risk of flooding. Through infiltration, the groundwater is replenished naturally and drying out is prevented.

Also applicable for…

  • the prevention of flooding on (heavy load) pavements, in gardens, around buildings and sports fields;
  • restore natural water balance by replenishing groundwater;
  • prevent the soil from drying out. Trees and plants enjoy rainwater longer.

Easy installation type D

Hydrorock® block are available in slim blocks of different sizes. The enormous buffering capacity and its dimensions limit the necessary digging activities. The blocks are placed either next to each other or behind each other and thus form the desired buffering and infiltration system.

Always fitting for each desired capacity and situation. Only the digging of small trenches is required and the cost for the removal of surplus soil is limited. In other words, flexibility and simplicity.

Type D Rainwater drainage & buffering
Type D-HD Rainwater drainage & buffering in High Density
Product Data Sheet Hydrorock 2019 English

Calculate your amount of Hydrorock units

The amount of Hydrorock units you require depends on the situation in which you intend to use them for.

Type Infiltration capacity Dimensions (lxbxh) Weight Construction depth Max. load per m2 Required number Total Buffer
BD112 112 liter 120x30x33 cm 9 kg 63 cm 2500
BD170 170 liter 120x30x50 cm 13.5 kg 80 cm 2500
BD220 220 liter 120x40x50 cm 15.5 kg 90 cm 2500
BD340 340 liter 120x30x100 cm 27 kg 130 cm 2500
BD440 440 liter 120x40x100 cm 35 kg 140 cm 2500
D34 34 liter 120x15x20 cm 2.7 kg 35 cm 2500
D45 45 liter 120x20x20 cm 3.6 kg 40 cm 2500
D112 112 liter 120x30x33 cm 9 kg 63 cm 2500
D170 170 liter 120x30x50 cm 13.5 kg 80 cm 2500
D220 220 liter 120x40x50 cm 15.5 kg 90 cm 2500
D340 340 liter 120x30x100 cm 27 kg 130 cm 2500
D440 440 liter 120x40x100 cm 35 kg 140 cm 2500

Why buffering and infiltration with Hydrorock?

The current flooding issues continue to be a source of major problems in urban areas. In many cases, rainwater that reaches the sewer via rain pipes is the cause. During periods of heavy rainfall, sewers overflow causing major issues in the surrounding area. Many local authorities aim to infiltrate as much rainwater into the soil instead of unnecessarily directing it to water treatment plants. It is for this reason that rainwater separation is mandatory for new development sites.

Urbanisation goes hand in hand with a significant increase in paved areas and therefore an increase in water supply to the sewer system. But the sewer system has not been dimensioned for this increase in many cases. With Hydrorock, rain water is separated from the system, buffers under the existing infrastructure and infiltrates into the surrounding soil. The result is a significantly smaller chance of flooding.

Simple and effective separation is possible with our  Hydrorock Type BD units. Easy and effective buffering and infiltration made possible with our Hydrorock Type D units.



Hydrorock maximum storage capacity of total volume

Frequently asked questions

This is a selection of questions we often get. Perhaps the answer to your question is included!

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+31 (0)10 30 20 000

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3125 BK Schiedam

The Netherlands

Where can I find the Hydrorock price overview?

For the most current prices, we advise you to contact your nearest Hydrorock International dealer. Look here for an overview of suppliers of Hydrorock solutions. They will be happy to make a customized offer for you. For prices and online ordering of individual Hydrorock® products you can look at the various web shops.

Is Hydrorock resistant against erosion by plant- and tree roots?

Hydrorock is produced from stone wool, a 100% natural material. It remains underground for decades in optimum condition. Hydrorock is resistant to erosion by plant and tree roots and will continue to function well for years. The cotton-based membrane of filter cloth does not mold or rot. It has a high breaking strength and is resistant to the natural substances in the soil. Stone wool is 100% recyclable. Flora and fauna thrive excellently on Hydrorock.

Can Hydrorock be used with high groundwater levels?

The infiltration blocks must always remain above groundwater level. The blocks would otherwise be filled with groundwater instead of surface water. Therefore, always check the groundwater level before you start construction. Local groundwater monitoring networks or the DINO counter (Data and Information from the Dutch Subsurface) can help you with this. At a high groundwater level, it is possible to work with blocks that have a lower height, such as the types D34 or D112.

How many Hydrorock infiltration blocks do I need?

The number of required Hydrorock® blocks depends on the surface, the groundwater level and the soil type. Use our calculator to calculate how many blocks you need. Our calculator for disconnecting rainwater can be found here. Look here for solutions to prevent flooding

How are the infiltration blocks placed?

Hydrorock blocks have a fine-grained fiber structure in one direction. A horizontal fiber direction promotes a drainage function. A vertical fiber direction promotes an infiltrating function. Due to the load-bearing capacity of the blocks, these must always be positioned in a vertical position for buffering and infiltrating action (the sticker with the text "this side up" is then on top). If bearing capacity is of secondary importance, the blocks can also be used horizontally for drainage purposes of surface and rainwater. For optimum drainage, we recommend placing the blocks one behind the other and in a horizontal position (lying down). You will find the placement instructions in the here.