Decentralized solutions for every rainwater management problem.

Projects are often put on the market integrally, with the engineer increasingly being challenged as part of consortia with contractors to come up with conceptual and innovative solutions for construction and infrastructure work. Important starting points frequently are: sustainability, climate adaptation and circularity.

“Demand is increasing due to urbanization and climate change towards sustainable and decentralized rainwater solutions”

Smart decentralized solutions

Hydrorock offers decentralized solutions to prevent flooding on the street in public spaces, on company sites, in green areas, gardens and on unpaved areas. The retention of rainwater on “own ground” is increasingly playing an important role; either by uncoupling rainwater drains but also by buffering and infiltrating rainwater to prevent from drying out.

Hydrorock assists engineering firms with smart decentralized solutions that make use of efficient and ecologically responsible materials and a sophisticated installation method. By placing the Hydrorock facilities locally across the entire site, a very gradual and controlled release of rainwater to the soil takes place. As a result, the groundwork is also more limited compared to (single) central solutions.

Innovative and ecologically responsible solutions with Hydrorock

Dutch engineering firms are among the largest and most specialized firms in the world in the field of water management. This is mainly due to the frequent rainfall, the swampy subsoil and the constant fight against the flood risk in the Dutch delta. More and more, engineering bureaus offer their added value in the field of rainwater management by means of an integrated plan of approach that involves both the technical solution and the increasing demand for sustainable and decentralized solutions. Hydrorock helps the engineering office on this website with customized information and, if required, advice.


View the documents available for the products that are tailored to engineering offices.

Brochure for House and garden
Brochure for Public space
Brochure for Conservation and agriculture
Brochure for Golf courses
Type D Rainwater drainage & buffering
Type D-HD Rainwater drainage & buffering in High Density
Type BD Hemelwater afkoppel & infiltratiesysteem
Type BD-HD Rainwater separation & infiltration – High Density
Type D34 Rainwater lineair drainage
Type IP15 RVS Infiltration drain with built in buffer
Product Performance Declaration – Hydrorock Products

More information

Need specifications? We are happy to send it to you.

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

's-Gravelandseweg 246

3125 BK Schiedam

The Netherlands

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

What is the permissible load / carrying capacity?

The permissible load of the standard Hydrorock infiltration blocks type D is 75 kg per m3. For the High Density version type HD, the standard load capacity is 120 kg per m3. For extra heavy loads, there is an XHD variant with a load capacity of 160 kg per m3. The infiltration solutions can be designed for various strengths on these three Hydrorock variants. Depending on the type of stone wool and the soil conditions, the typical installation depths for the various traffic classes are shown here.

How much maintenance does the Hydrorock system require?

If the blocks are positioned correctly, the system requires no maintenance. Unlike other solutions, running in of soil is not possible in this system. The blocks therefore do not need to be inspected or cleaned. When uncoupling rainwater discharges it must be prevented that dirt blocks the pipes. This is easy to do by placing a foliage and sand catcher. These systems are easy and quick to clean. If there is a wish to still be able to clean the system extra, we advise you to install the uncoupling system in a loop. In this way the system can be sprayed through and therefore easy to clean should there still be some dirt blockage.

What is the water absorption capacity of the infiltration blocks in terms of time?

The speed with which Hydrorock blocks blocks of water depends on how the water can reach the blocks. If water comes in direct contact with the blocks, the speed at which the blocks absorb the water is approximately 400 liters per m2 per minute. If water reaches the blocks via a porous layer of, for example, sand, then sand has a delaying effect in this case and is then also normative. The absorption capacity / permeation speed of porous sand is approximately 50/60 liters per hour, which means that 50 liters of water on an area of 1 m2 takes 1 hour to sink into this. Absorption of water via the perforated tube in type BD blocks proceeds at a speed of 100 liters per linear meter of tube per minute.

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.