Stormwater retention · Infiltration · Storage
Water storage beneath trafficked surfaces.
JUMBO BLOCK is a modular heavy-duty system made of high-performance concrete. It retains heavy rainfall beneath roads, squares and operational areas, lets it infiltrate or stores it – walk-in, maintainable and, if required, digitally monitored.
The module in figures
- Storage volume
- 13.9 m³net per module
- Edge length
- 2.5 mcube, walk-in
- Load capacity
- LM1EN 1991-2
- Service life
- 80–120 yrsdesign to EN 1990
One system for every case
What is JUMBO BLOCK?
A JUMBO BLOCK is a precast concrete cube with an edge length of 2.5 m. Twelve beams with a 0.25 m × 0.25 m cross-section form the load-bearing frame. The modules are laid as an interconnected single layer, each rotated by 90°; floor, wall and cover plates close the installation along its outer contour and are sealed with SABA EcoSeal. The result is a continuous, walk-in storage space of any size.
One system covers four tasks:
- Retention – buffer heavy rain and discharge it at a controlled rate
- Infiltration – return water to the ground on strip foundations
- Storage – use rainwater for irrigation, cooling and operations
- Fire water – hold reserves or retain contaminated fire-fighting water
Technical data
Key data per module
| Outer dimensions (L × W × H) | 2.5 m × 2.5 m × 2.5 m |
|---|---|
| Clear width (L × W) | 2.0 m × 2.0 m |
| Gross volume | 15.6 m³ |
| Storage volume (net) | 13.9 m³ |
| Dead weight (dry) | approx. 4.2 t |
| Load capacity | Traffic load to EN 1991-2, load model LM1 |
| Design service life | 80–120 years to EN 1990 |
Example: 40 modules provide around 556 m³ of retention volume.
Applications
Where JUMBO BLOCK is used
Wherever surfaces are sealed, carry heavy loads and failures are costly.
-
Municipalities
Flood protection with retention space beneath streets, squares and parks.
-
Industry & commerce
Flood protection, process water and space savings for industrial sites.
-
Roads & transport infrastructure
Heavy-duty retention integrated into the road structure.
-
Fire-water storage & retention
Store fire-fighting water and safely retain contaminated water.
All applications: including ports, airports, agriculture and forestry →
Digital security for critical infrastructure
Monitored. Verifiable. KRITIS-ready.
On request, every installation is fitted with sensors and the JUMBO BLOCK Dashboard. It shows fill levels and status in real time and records measurements in a tamper-evident way, anchored via IOTA technology. The IT system is protected by a registered intellectual property right.
The dashboard helps operators meet the requirements of NIS-2, the German KRITIS umbrella act and the Cyber Resilience Act (CRA) in a traceable way – with full data sovereignty.
Free planning certainty
JUMBO BLOCK Engineering Suite
The Engineering Suite at jumboblock.org calculates the hydrological retention requirement, determines the number of modules, produces an initial layout and estimates costs – offline-capable, traceable and free of charge.
It also includes resilience tools for critical infrastructure that support everyday operations and keep teams able to act during IT outages.
Climate adaptation
True Sponge City 2.0
Land is used twice: water storage below, traffic, buildings or green space above. Stored rainwater cools during heatwaves, supplies trees in dry spells and relieves the sewer system during heavy rain.
See it for real
The demonstration module in Weißensee
A full-size JUMBO BLOCK is on display at our partner plant BBW® Weißensee in Thuringia, Germany. See the solid construction and the SABA sealing up close. We are happy to arrange a visit.
News
From the blog
ZANNI GROUP – A Commitment to Germany
New address, clear direction: ZANNI GROUP has moved to zanni.de – with JUMBO BLOCK and the Engineering Suite at the heart of its work.
Concrete Against Heavy Rain. Software for Emergencies.
One page now shows what JUMBO BLOCK is and can do: jumboblock.org/info – the module, the Engineering Suite, KRITIS tools and the live dashboard.
JUMBO BLOCK Rescue – When Digital Resilience Becomes Practical
A bootable MX Linux rescue and work system with 35 tools for data recovery, diagnostics and security – plus the complete Engineering Suite.
FAQ
Quick answers
What is JUMBO BLOCK?
JUMBO BLOCK is a modular precast concrete system by ZANNI GROUP for underground stormwater retention, infiltration and storage. Each module is a 2.5 m cube with 13.9 m³ of net storage.
How much water does one JUMBO BLOCK hold?
One module has a gross volume of 15.6 m³ and a usable storage volume of 13.9 m³. 40 modules provide around 556 m³.
Can JUMBO BLOCK be driven over?
Yes. The system is designed for traffic loads to EN 1991-2, load model LM1, and can be installed under roads, car parks, industrial sites and airport areas.
Planning retention or fire-water storage?
We support planners, municipalities and operators from initial sizing through to operation.