How much washout water do you use?
A Facebook survey, sent to ready-mixed truck drivers, focused on understanding the volume of water used for mixing drum cleaning . The Question:
“How much washout water does your company use per truck at end of day?”
Wastewater control and management are very important environmental issues for our communities. Because concrete is the most widely used building material, we need to understand water volumes and limit unnecessary wastewater. Water used during ready-mix drum clean-up is a critical operational question.
The drivers responded to the survey that they use from 30-gallons to 800-gallons during clean-up. Some even said that they “fill up the entire drum”, while others said that they use rocks for clean-up due to $25,000 wastewater fines that their companies had received.
Washout Survey Results
Drivers and ready-mix dispatchers joined in the survey from both the US and Canada. When all of the numbers were in they found that 225.99-gallons (average) of washout water is used in each truck at the end of the day. About 30% of the respondents mentioned that they wash the drums into a recycling system, while many more did not disclose how the wastewater was disposed of. Our experience is that most ready-mix locations use some type of wastewater recycling system like a settling pond or group of ponds.
Washout Water and Short-Load Concrete
A 10-yard concrete truck drum is a massive mixture of fins and spiraling steel. Sadly, it doesn’t matter if you order 10-yards or 1-yard, the entire drum gets dirty from the concrete mixing process. Since the wet concrete touches all of the drum, it all needs to be washed down. One of the sad consequences of using a big truck to deliver a small load of concrete is the volume of wastewater created from this choice. The best way to imagine the volume is to picture a pallet of 45 five-gallon buckets. This is the volume of water that is needed to wash down all those surfaces in a 10-yard drum.
In contrast, a 1-yard Cart-Away mixer only requires about 5-gallons of water to do a washout from a short-load delivery of concrete. It takes less water because of the smaller drum. In addition, the Cart-Away drum tilts down to ease access to all of the interior surfaces. These trailers reduce the water impact in the waste stream for a community. It is environmentally better to use small Cart-Away trailers to complete small concrete projects. These trailers makes an enormous difference in the volume of water needed to provide your community with its short-load concrete needs.