A new TERRATEC TBM is being lowered in the Metropolitan Waterworks Authority’s Ninth Bangkok Water Supply Improvement project in Thailand.

In early October, a TERRATEC 4.8m diameter Earth Pressure Balance Tunnel Boring Machine (EPBM) is lowered into place for the Metropolitan Waterworks Authority’s Ninth Bangkok Water Supply Improvement project. The occasion was witnessed by representatives from Bangkok’s Metropolitan Waterworks Authority (MWA) and the contractor, Italian Thai-Nawarat Joint Venture.

This significant project will deploy three new TERRATEC TBMs to construct a 9.1 km water tunnel on the western side of Bangkok. Managed by the joint venture of Italian-Thai (ITD) and Nawarat (NWR), the project will see ITD operating two TBMs (S105 & S106) and NWR managing one TBM (S102) which is now being lowered into the vacant Shaft 9B-1 to begin boring approximately 2.2km in the opposite direction, aiming to connect with Shaft 9A-5 from another contract.

Designed to meet the project’s stringent alignment requirements, these machines feature active-type articulation capable of navigating minimum curve radius of 90m and 80m. These will be the 6th, 7th, and 8th “tight radius” machines from TERRATEC in Thailand.

The geological conditions along the tunnel alignment, consisting of silty clayey sand and very stiff to hard clay, will challenge the TBMs’ soft ground cutterheads, which boast a 70% opening ratio and copy cutters. The machine will progress using traditionally reinforced concrete segments, with a secondary steel lining installed post-excavation.

Tunnelling through sand can be quick, but it comes with the risk of water and sand ingress, which could severely result in tunnel collapse. Previous projects in Bangkok have faced such challenges. Consequently, the TBM design and tunnelling team must implement necessary precautions and exercise great caution.

The Ninth Bangkok Water Supply Improvement project aims to enhance water supply capacity, part of a series of MEA-led tunnelling initiatives addressing increased demand, leakage reduction, and water quality enhancement in Bangkok.

TERRATEC’s experienced Field Service staff will assist machine operations, ensuring optimal performance and successful project completion. Having established a strong regional base in Thailand over the past decade, beginning with the MRT Blue Line Extension Project, TERRATEC stands as the country’s premier TBM supplier, known for robust, tailor-made designs, prompt onsite assistance, and readily available TBM spares and support.

Terratec press release.