The challenge

As part of the reconstruction project for Fabryczna Street in Leszno, western Poland, a solution for water retention and release was needed. Collecting excess water to keep the surface area free meant bringing in a retention tank solution that could capture and release storm water into the sewage system.

The solution

A corrugated steel retention tank system consisting of two retention tanks was built into the existing sewage system at Fabryczna Street. The tanks are placed in a car-free green zone, and the tank solution gradually releases excess stormwater into the sewage system. Installed gradually over a three-month period, the retention tank solution is one of the largest-capacity retention tank projects ViaCon Polska has delivered.

The ViaCon advantage

The water tank solution offers a number of benefits:

• Faster installation than alternatives
• Cost effective: Short construction time and easier maintenance reduces overall costs
• Sustainable steel solution
• Flexible build: System built under a road, car park or car-free zone and multiple, customizable arrangements for tanks and their capacity and capabilities

Technical specifications

The two-tank system included specific design requirements and assumptions:
• Two retention tanks:
o Tank 1: DN/ID 1,400 mm
o Tank 2: DN/ID 1,500 mm
• Anti-corrosion with 42 µm thick zinc coating and polymeric WProtect coating of min 250 µm on both sides

Tank 1 has a total capacity of 676.4 m3 with an inner diameter of 1,400 mm. Three pipes are arranged in parallel, each 142 m long for a total length of 426 m.

Tank 2 has a total capacity of 382.9 m3 with an inner diameter of 1,500 mm. Two pipes are arranged in parallel, each 108.4 m long for a total length of 216.8 m.