Water Treatment for Bus Companies
When Eddie Stobart was asked what he put his success down to, he was unequivocal. Clean trucks. He discovered that cleaning up the image of trucking had a big impact on sales and significantly reduced maintenance and repair costs. Even in 1985 when Stobart had 26 trucks, he would still clean the fleet himself.
The same is true in the bus and coach business where the cargo is infinitely more precious and a lot more demanding.
Keeping your fleet clean is a major undertaking and one which puts considerable strain on finances with the rising cost of fresh water and the cost of labour. It takes on average 500 gallons to wash a bus with a hose, so the nightly wash can add up to thousands of gallons. Of course, an automated wash can dramatically reduce water usage but there is still a hefty water bill to pay.
So what can be done to reduce the water footprint of a bus operator? Firstly, you need to examine the source of the water and, where possible, avoid turning on the mains tap.
Operator sites near a river can apply for an abstraction licence to take water from the river which then needs to be filtered before use. An alternative would be to use water from a bore hole, but not everyone is fortunate enough to have a watercourse running close by.
By far the most efficient way to capture water is to take advantage of our rainy climate and harvest rain water direct from the rooves of your buildings. Bus garages provide the ideal trap for collecting rainwater with extensive roofing. Given the UK gets an average of 33 inches of rain a year, the potential to accumulate thousands of gallons is well within reach. Experts estimate that for every inch of rain that falls on a catchment area of 1,000 square feet, you can expect to collect approximately 600 gallons of rainwater. Ten inches of rain falling on a 1,000 square foot catchment area will generate about 6,000 gallons of rainwater. It is then simply a matter of connecting the drainpipes to a suitable reservoir and installing a basic filtration system as rainwater does contain contaminants.
The only flaw with rainwater harvesting is lack of rain. If it does not rain, then the reservoir will soon empty and you’ll have to switch back to mains water. However, the installation of a reclaim system that can recycle around 90% of used water is an attractive option. The systems can be retrofitted to existing wash machinery.
Firstly, the water is collected in a sludge interceptor which separates the large contaminants by allowing them to settle at the bottom of the tank. Next, the water is passed through a cyclonic filter and finally through activated granular carbon vessel to remove any remain organics and chemicals. The recycled water can be further treated with dosed with an organic biocide or an oxidising agent. A final treatment of reverse osmosis is required if a spot free rinse is offered.
It’s not only financial concerns that need to be taken into consideration. The impact on the environment of allowing contaminated water to drain into the public system is considerable as it will be heavily polluted with oils and chemicals from the cleaning process. The Environment Agency makes it clear that it is illegal to discharge “trade effluent into drains without permission.
Understanding your drainage system is the key to preventing pollution. Most areas have what is known as a separate drainage system where there are two types of drain:
Surface water or clean water drains should only carry uncontaminated rainwater; they lead directly to ditches, streams, burns, rivers and soakaways. Roof water, car park, road and some yard drainage is usually connected to the surface water drainage system
Foul water drains carry contaminated water (sewage and/or trade effluent) safely to a sewage treatment facility, which is either owned privately or by the local sewage treatment provider.
Jon West, managing director of Kirton Water Treatment Systems which specialises in waste water reclaims, said:” Water treatment systems are a prerequisite for any bus washing operation and will quickly show a return on investment and help fulfil a responsibility to the environment.”
