Contamination

The most common route for contamination is known as ‘back flow’. What does this mean? Well, normally the cold water coming into your house is under a fair amount of pressure. Harringay Plumbers can fit devices in pipework Not only does this speed up the filling of your bath or the watering of your garden but it also ensures 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? Let’s suppose that a builder has just dug straight through the mains pipe 2miles down the road from your home. Suddenly you find yourself with little or no water. So you drop the hose and wander back to the house looking for kinks in the hose. While you are doing this the water on your garden suddenly finds itself getting sucked back into the now empty hose, and eventually, back into the mains cold water supply. Sadly this water is mixed with dog dirt, pesticides, plant food and goodness knows what else. Of course it’s the builder’s fault that the mains has lost its pressure but it still your fault that you just contaminated the water supply and poisoned half of your neighbours. To prevent such scenarios the water regulations insist that you have devices for preventing ‘back flow’. A Harringay Plumber fits valves. In the case of the hosepipe example, you should have what is called a ‘double check’ valve on the outside tap. This 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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