Pumping Station Construction (Flood)

Toolbox Talk Record

Ref: TBT-DAM-013  |  Issue: 1  |  Date: March 2026
PresenterProject
LocationDate

What?

Why?

Flood riskThe construction site is in a flood-prone location — the risk of sudden inundation is real and must be actively managed.
Deep excavationsHigh groundwater and soft ground make deep excavations for wet wells particularly hazardous.
Confined spacesBelow-ground chambers and wet wells created during construction become confined spaces requiring formal controls.
Do Don't
  • Monitor flood warnings and river levels continuously throughout the construction period
  • Maintain dewatering systems with standby pump capacity at all times
  • Establish flood evacuation trigger levels and brief all workers on the escape plan
  • Treat all below-ground chambers and wet wells as confined spaces during construction
  • Obtain environmental permits for temporary discharge of pumped groundwater
  • Assess ground conditions for plant stability before positioning heavy equipment
  • Install edge protection around deep excavations and wet well openings
  • Coordinate MEICA installation with civil works to avoid trade clashes below ground
  • Maintain site access roads so emergency evacuation vehicles can exit at all times
  • Test commissioning procedures under controlled conditions with full rescue standby
  • DON'T work on the site during active flood warnings without specific authorisation
  • DON'T allow dewatering pumps to stop without backup — the excavation will flood rapidly
  • DON'T enter wet wells or sumps without confined space permits and rescue plans
  • DON'T ignore rising groundwater levels — increase dewatering capacity and reassess
  • DON'T discharge pumped water without the required environmental permit
  • DON'T position heavy plant on waterlogged ground without ground assessment
  • DON'T block the site access road with materials — emergency exit must always be clear
  • DON'T start commissioning with water without briefing the team on drowning risks
  • DON'T leave excavation edges unprotected near wet well openings
  • DON'T assume dry weather means no flood risk — upstream events travel downstream

See also: Flood Defence Construction Safety | Dewatering (Wellpoints and Sumps)