Rain Gardens

Buffers run off efficiently

94% absorption means rapid management of run off from road or local hard landscaping

Totally configurable

Modular nature allows extra capacity to be added. In-ground problems can be negotiated 'live' during installation

Streamlined installation

Minimal excavation needed and block can be configured to suit unusual shapes

Fully integratable

With Hydrorock infiltration or attenuation filter drain systems, or if retrofitted, with other existing systems

Blocks configurable to suit space
94% absorption by volume
Attenuation and/or infiltration options

Hydrorock natural aquifer blocks offer a range of solutions for urban rain gardens. Rainwater is captured and held either to be released into the piped network via attenuation options or released into the ground through infiltration.

  • Hydrorock blocks can be easily configured to suit rain garden dimensions
  • Configurability retrofit applications and in-ground problems are easily dealt with
  • Low dig options add further flexibility
  • Uniquely high absorption to volume ratio (94%)
  • 100% natural product
  • Recyclable
  • Non-plastic solution, no micro particle release
  • Requires minimal excavation
  • Full integratable with other Hydrorock infiltration or filter drain systems
  • Excellent load bearing up to 40 tonnes and life time system integrity


Design detailing

‘Low dig’ rain garden block configuration, where site conditions require shallow excavation.


Installation is very simple and quick with minimal disruption.
Blocks are pre-wrapped with filter membrane, so the excavation needs to be only as large as the system (no access is required to fit the membrane).

  • No specialist installation engineering or equipment is needed, with simple push-together blocks and snap-together fittings which require no special skills or tools
  • Hydrorock natural aquifer blocks can be used in single or multiple layers, on a 100 mm layer of sand. This increases the surface area of the bottom of the system
  • Multiple block configurations are possible to suit site requirements
  • Extra capacity is provided by adding further blocks, which, on contact with others, become unitary aquifers
  • Hydrorock BD blocks have integrated perforated pipes allowing rapid inflow and storage water in each block underground.
  • Additional capacity can be rapidly and easily achieved by the addition of further Hydrorock BD blocks or Hydrorock B blocks (pre-wrapped but without integrated pipes)
  • The system can be placed around existing infrastructure, such as pipes and cables unlike crated sumps. This flexibility allows for optimisation of the site.
  • Placing the system on a 100mm layer of sand will permit infiltration from the module into the surrounding soil and facilitate the discharge of water from the Hydrorock blocks.




Click here to use our calculator and quickly calculate the number and volume of Hydrorock natural aquifer blocks needed for your application.


Hydrorock natural aquifer blocks are available to provide 100% sustainable, 100% recyclable water management solutions.

D Block
D Block
BD Block
BD Block
DHD Block
DHD Block
BDHD Block
BDHD Block
BD Block
IR Block
LG Block
LG and SL Blocks
IP Range
IP Range
Filter units
Filter units
Hydrorock fixings and connectors
Hydrorock fixings and connectors