Heavy and persistent rain turns construction sites into hazardous environments. Waterlogged ground reduces bearing capacity, causes excavation instability, and creates deep mud that traps workers and plant. Slips, trips, and vehicle bogging are among the most common wet weather incidents on UK sites. This talk covers the controls needed to work safely when the ground is saturated and conditions deteriorate.
Key Hazards
Excavation collapse from saturated and weakened ground conditions
Plant bogging down in deep mud causing recovery and tipping risks
Slips and falls on muddy access routes and working platforms
Flooded excavations concealing trip hazards and open voids
Control Measures
Inspect all excavations after heavy rain before allowing anyone to re-enter.
Pump out standing water from excavations before work resumes and monitor inflow rates.
Lay temporary trackway or bog mats on soft ground to maintain safe access for plant and pedestrians.
Reduce vehicle speed on all haul roads and access routes during wet conditions.
Increase the frequency of housekeeping and maintain drainage channels to direct water off site.
Provide boot wash stations and additional matting at welfare facility entrances.
Review the stability of temporary works, stockpiles, and embankments after prolonged rain.
Issue waterproof PPE and ensure operatives change wet clothing at regular intervals.
Stop work on slopes and embankments if the ground becomes too soft for safe plant operation.
Remember
Always inspect excavations after heavy rain before anyone enters them again
Lay temporary trackway on soft ground to prevent plant and pedestrians from bogging
Reduce vehicle speed on all haul roads and access routes in wet conditions
Pump out standing water from excavations before work resumes each day
Review temporary works and embankment stability after prolonged or heavy rainfall
Change wet clothing regularly and use the drying facilities provided on site
Applicable Legislation: CDM 2015 · Health and Safety at Work etc. Act 1974 · MHSWR 1999 · Workplace (Health, Safety and Welfare) Regulations 1992