In partnership with Krah Pipes OÜ
An aging underground concrete water tank in Aarhus, Denmark, has been replaced with a more reliable and efficient solution using Borealis polyethylene (PE) materials. In this first-of-its-kind project, pipe supplier Krah Pipes OÜ manufactured six segments of giant plastic pipe, each 3000mm in diameter, to replace the old structure.
Together, they store 2000m³ of drinking water.Krah Pipes OÜ specializes in large-diameter thermoplastic pipes, providing custom solutions for infrastructure projects worldwide.
This project is the latest in our long-standing partnership with Krah Pipes OÜ, combining our advanced PE materials with their expertise in pipe manufacturing to deliver high-performance pipe systems for modern water infrastructure.
The old concrete tank required divers to inspect and clean it every five years. Cracks and leaks were difficult to detect and often went unnoticed until repairs became urgent. The cracks also posed a risk of external water seeping in, potentially contaminating the stored supply.
The new system reduces these risks and brings significant advantages: A pressurized dual-wall design ensures tightness and security, and a tilted layout allows sediment to wash away naturally, reducing the need for manual cleaning. Maintenance is also easier, as pressure monitoring eliminates the need for deep diving inspections.
In addition to improving efficiency, the pipes support sustainability with an expected service life of at least 100 years, reducing material use and the environmental impact of replacement.
Six massive thermoplastic pipe segments, crafted by Krah Pipes OÜ with BorSafe™ PE100-RC materials, now store 2000m³ of drinking water—replacing a deteriorating concrete tank and setting a new standard for water infrastructure.
© Krah Pipe OÜ
BorSafe™ HE3490-LS-H offers exceptional resistance to slow crack growth and rapid crack propagation, ensuring durability in demanding applications.
The pipes are made using two advanced PE grades based on proprietary Borstar® polymerization technology. The main pipe body is constructed from BorSafe™ HE3490-LS-H, a high-density PE100-RC-classified PE compound developed for pressure pipes. It offers exceptional resistance to slow crack growth and rapid crack propagation, ensuring durability in demanding applications.
The yellow inner layer, made of BorSafe™ HE3493-LS-H - also a PE100-RC-classified material - adds extra functionality to the system, as the light color makes it easier to carry out visual inspections by camera when needed.
"Maintaining aging water infrastructure is a growing challenge, and reactive repairs are rarely an efficient solution. This project demonstrates how replacing older-generation materials with advanced PE solutions can improve long-term performance, simplify maintenance, and support sustainability. Through our long-standing partnership with Krah Pipes OÜ, we’re helping our customers put this approach into practice, improving water security for communities."
John Webster, Borealis Head of Marketing Infrastructure and Building
This approach has proven so effective that another old tank in Aarhus has already been replaced using the same concept and materials. It’s a great example of how Borealis is enabling life’s essentials, providing durable and sustainable solutions for critical infrastructure projects.
Six massive thermoplastic pipe segments, crafted by Krah Pipes OÜ with BorSafe™ PE100-RC materials, now store 2000m³ of drinking water—replacing a deteriorating concrete tank and setting a new standard for water infrastructure.
© Krah Pipe OÜ
"The combination of our advanced manufacturing capabilities and Borealis’ high-performance polyethylene materials has delivered a durable and low-maintenance alternative to traditional water storage systems. The successful implementation in Aarhus sets a strong example for other cities looking to upgrade their infrastructure with modern solutions."
Peeter Kirtsi, CEO Krah Pipes OÜ