STEP Regional Odour Control Facilities System
Odour control is a key component of STEP - Strategic Tunnel Enhancement Programme for Sewer system. A centralized odour extraction approach was initially recommended and validated through detailed modeling. However, ADSSC required greater certainty regarding the volumes and movement of air within the tunnel and link sewers so it directed that physical modeling be conducted to quantify air entrainment values at drop structures and further evaluate centralized versus regional odour extraction system approaches. As an outcome, a regional odour extraction system was implemented at shaft WS-4 and at shaft WS-7, with a two stage treatment consisting of bio-trickling filters followed by carbon polishing.
Due to deep excavation work, instrumentation monitoring was important for risk assessment. Geotechnical and geodetic instruments were installed in diaphragm wall and soil to provide settlement, deflection and deformation data for the verification of initial design of permanent structures and temporary works supporting the excavation.
Encardio Rite’s sister concern Rite Geosystems LLC in UAE was entrusted with the complete monitoring works of the project that included
- Supply, installation and monitoring of geotechnical instruments that included inclinometer, prism targets and settlement points
- Optical Surveying
- Daily & weekly reporting with evaluation & interpretation