Wet weather transforms earthworks operations. Soil becomes heavier, slopes become unstable, trenches flood, and plant loses traction on saturated ground. Continuing earthworks during or after heavy rain without adjusting methods and controls can lead to slope failures, plant overturning, and trench collapse. This talk explains the additional risks of working in wet conditions and the controls that must be applied.
Key Hazards
Slope failure from saturated soil reducing the stable angle of cut faces
Plant overturning on soft waterlogged ground losing traction and stability
Trench flooding creating drowning hazards and undermining support systems
Increased weight of saturated material exceeding vehicle and lifting capacities
Control Measures
Monitor weather forecasts daily and plan earthworks activities around expected rainfall periods.
Reduce batter angles and increase support where rainfall has saturated excavation slopes.
Inspect all excavations before each shift and again after any period of significant rainfall.
Pump standing water from excavations before allowing anyone to enter or resume work.
Use bog mats or track mats to improve ground bearing capacity for plant in waterlogged areas.
Reduce vehicle loads on haul roads when saturated ground reduces the road's bearing capacity.
Cover exposed earthwork surfaces with sheeting to prevent further water absorption where possible.
Stop work and reassess if ground conditions become unsafe for the planned earthworks operations.
Ensure surface water is channelled away from excavation edges using cut-off drains or bunds.
Remember
Monitor weather forecasts daily and plan earthworks around expected rainfall periods
Inspect all excavations before each shift and again after any significant period of rainfall
Pump standing water from excavations before allowing anyone to enter or resume work below
Use bog mats or track mats for plant operating on waterlogged ground to maintain stability
Stop work and reassess if ground conditions deteriorate beyond the planned earthworks parameters
Channel surface water away from excavation edges using cut-off drains or bunds
Applicable Legislation: CDM Regulations 2015 · BS 6031:2009 (Earthworks) · Health and Safety at Work etc. Act 1974 · Management of Health and Safety at Work Regulations 1999