Contaminated Supply

When it happens it can be a real nightmare for a homeowner to rectify and should really be handed over to a professional service straight away and more importantly it is hazardous to health. The best known way for contamination to occur is through something known as ‘back flow’. What is back flow? Well, normally the cold water coming into your house is under a large amount of pressure. N11 Plumbers can fit devices in pipework. This will speed up the filling of your bath or the watering of your garden but it also guarantees that water is only flowing in one direction, i.e. out of the hosepipe and onto your lawn. In this arrangement nothing can contaminate the mains cold-water pipework because little or nothing can get into it, but what happens if the pressure was suddenly to drop? Suppose a builder had just dug straight through the mains pipe a few miles down the road from where you live. This results in no water to your home. As you are in the garden, you drop the hose and go back to the house looking for twists in the hose.

As you are doing this, the water in your garden suddenly finds itself getting sucked back into the now empty hose, and eventually, back into the mains cold water supply. The water now is, potentially mixed with dog dirt, pesticides, plant food and lots more foreign bodies. The fault of lost pressure lies with the builder, but it is you that have contaminated your water supply and half of your neighbours also. To stop such things occurring, the water regulations insist that you fit devices for preventing ‘back flow’. An N11 Plumber fits different valves. For the hosepipe example, you should have what is called a ‘double check’ valve on the outside tap. It is a simple device that will only ever allow the water to flow one way. If this is fitted and you lose pressure, it doesn’t matter because your tap will not let water flow back into the main supply contaminating it.
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