CASE STUDY: UTRANAZZ DEVELOPS BESPOKE CONCRETE MIXERS FOR THE HONG KONG WEST DRAINAGE TUNNEL

Case Study: Utranazz Develops Bespoke Concrete Mixers for the Hong Kong West Drainage Tunnel

Overview

Utranazz, the UK’s leading supplier of concrete equipment, engineered two unique rough-terrain concrete mixers for the Dragages–Nishimatsu Joint Venture working on the Hong Kong West Drainage Tunnel—a major infrastructure project designed to reduce flooding across Northern Hong Kong Island.

To meet the highly restrictive spatial and environmental conditions within the 11 km tunnel, Utranazz developed the Hydromix 2000 SL Tunnel Mixers: the smallest 2m³ rough terrain concrete mixers ever manufactured, measuring only 1600mm wide, 1877mm high, and 5677mm long.

Client Challenge

The construction team required concrete mixers that could:

• Operate within extremely narrow and low tunnel dimensions
• Produce and transport 2m³ batches of concrete despite size constraints
• Navigate uneven, confined environments with full 4-wheel-drive capability
• Meet stringent safety regulations for engine emissions and spark control inside enclosed spaces
• Provide excellent visibility for operators moving along long tunnel sections

No standard concrete mixer on the market could meet these combined requirements.

Utranazz’s Bespoke Solution: The Hydromix 2000 SL Tunnel Mixer

Utranazz designed the Hydromix 2000 SL Tunnel Mixers from the ground up, completing the project over five months.

Key Engineering Innovations

• Ultra-Compact Dimensions
  At just 1.6m wide and 1.877m high, the mixers meet strict tunnel access requirements without compromising on 2m³ output capacity.
• Specialised Perkins 804D Engines
  Each mixer features an engine fitted with:
  • Exhaust purifiers
  • Spark arrestors
  • Emission controls for confined-space operation
• Enhanced Operator Safety
  Front and rear CCTV systems were installed to give operators full visibility in the dark, tight tunnel environment.
• Rough-Terrain Performance
  4-wheel drive capability enables the mixers to operate reliably on uneven access roads and tunnel floors.

Role in the Drainage Tunnel Project

The two Hydromix 2000 SL units operate at opposite ends of the 11km Hong Kong West Drainage Tunnel, running between Tai Hang and Cyberport.

They play a critical role by:

• Transporting, agitating, and delivering concrete and shotcrete rapidly
• Feeding concrete pumps and spraying machines used to line tunnel walls
• Ensuring concrete arrives fresh, fully agitated, and ready for immediate use
• Supporting construction on a tight schedule and in logistically complex conditions

Their compact size and reliability help maintain rapid progress on the drainage tunnel—an essential project designed to relieve stormwater load, bypass overstretched urban drainage systems, and significantly reduce flooding risks in the region.

Project Impact

Utranazz’s bespoke engineering:

• Enabled safe and efficient concrete delivery in confined spaces
• Provided a solution unavailable from any standard equipment manufacturer
• Helped maintain productivity across a challenging, high-profile infrastructure project
• Demonstrated Utranazz’s capability to design highly specialised concrete equipment for extreme environments

For More Information

Suzy Wiseman
Marketing Manager, Utranazz Ltd
Tel: 01280 820770
Email: [email protected]