Specific Tasks

Piling and abutment works

Piling and abutment works require works within the CMA, including working above the water. This creates a challenging working environment where preparation and planning is critical.

Piling works also often require temporary staging to get the piling rig into position to do the main designed works. The main environmental issues around piling relate to the auguring of marine muds from within the temporary casings and how this is removed from the casing and offsite. You will need methodologies and procedures to minimise the discharge of sediment during this process.

If the abutment works are within or next to the CMA, the preparation works often involve a minor reclamation or erosion protection works.

Discharge of Estuary of Avon and Heathcote Rivers / Ihutai water from the repair of the Bridge St bridge (Source: Fulton Hogan).

Pile repair activities on a major bridge across an estuary (source: Fulton Hogan).

Issues to look out for

Design essentials

Issues to look out for

All piling operations (auguring and removal of the marine sediments, concrete pours and all other related concrete activates) are done over water. You need methodologies and procedures to minimise the discharge of sediment/concrete-contaminated water or dust to the CMA.

Sheet pile coffer dam installed for ground improvement works to install a bridge abutment (Source: SouthernSkies).

Design essentials

Plan the works to minimise both the extent and duration of the operation
Any temporary staging should have kick boards installed and spill kits on the deck
Plan how you will remove the temporary staging at the end of the works
Consider in detail the design of the abutment and abutment protection works and aim to minimise reclamations
Keep all works areas above water clean and tidy
Use staging screens and skips bins to manage the environmental effects.

Screens and staging installed to stop concrete and concrete dust dropping into the coastal marine area (Source: SouthernSkies).