Hiring a pump
Concrete washout: rules, options and who's responsible
Pump washout water is highly alkaline and must never reach stormwater drains — fines apply in every Australian state. Provide a lined washout pit, a bunded area or a washout bag on site; the pump crew does the washing, the site provides the legal place to do it.
Why it's regulated
Washwater from a pump carries cement fines with a pH around 12 — caustic enough to burn skin and lethal to creeks and fish if it hits stormwater. Councils and EPAs treat concrete washout into drains as pollution, with on-the-spot fines for the operator AND the site. Nobody argues after the event; everyone should plan before it.
Your options on site
A lined washout pit or bunded corner where slurry can dry for later disposal is the classic answer on bigger sites. On residential jobs the practical options are: a section of the pour that's still open (footings being backfilled), a plastic-lined bin or wheelbarrow, or a purpose-made washout bag — most pumps carry them and charge them on the docket (typically $50–$80). Agree the washout spot when booking, not when the hopper's full.
Who does what
The pump crew washes the machine, hopper and line — that's their gear and their time. The site provides the legal location and handles the dried waste with the rest of the concrete waste stream. If there's genuinely nowhere to wash out, say so at booking: some companies can wash out back at the yard, but they'll want to know before they leave it.
Sort it at booking — post your job — Note the washout plan when posting on PumpX and there's nothing to argue about on pour day.
Quick answers
How much water does a pump washout use?
Typically a few hundred litres for a boom's hopper and boom line; more with long ground lines. Site taps are normally fine — flag it if water's not connected yet.
Can washout go in the excavation?
Often yes — into an area being backfilled or a footing trench with the engineer's blessing, kept away from drains. Confirm with your builder; never into the street or a stormwater pit.
What's a washout bag?
A heavy geotextile bag that captures slurry and lets water evaporate; the dried solids go out as waste. Pumps carry them for sites with no washout area — it appears as an extra on your docket.
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Updated 2026-07-19 · PumpX Guides — written by the industry, for the industry.