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- Best practice trenching guidelines
These guidelines ensure work on Council infrastructure considers and mitigates environmental risks associated with underground excavations.
Forward planning in the early stages of a project can reduce costs and risks associated with excavations and wastewater diversions. Whilst adequate trench support is crucial to provide a safe working environment, options to provide this can vary considerably in their impact on progress and costs.
Well planned dewatering maintains the stability of the excavation and protects the groundwater environment. Effective overpumping removes risks of contamination whilst facilitating infrastructure replacement in a live network environment.
Use these guidelines to support the preparation of a site Environmental Management Plan and as a means of confirming the application of a 'Best practicable option':
- Trench Support Best Practice Guideline [PDF, 369 KB]
- Dewatering Guideline [PDF, 2.5 MB]
- Wastewater Overpumping Best Practice Guide [PDF, 4.1 MB]
The appendices to the Overpumping Guide [DOCX, 45 KB] can be amended for inclusion with your Environmental Management Plan.