SAS Urban Survival Handbook by John Wiseman

damage begins to show, the remedial work may be expensive or very difficult. Your home could become damp and smell damp. Your health could suffer.

PLUMBING DECISIONS
     
    Simple plumbing jobs, such as changing the washer in a leaky tap or in the valve in a ball-cock assembly, are not very difficult and could be attempted by the beginner. Larger jobs, which might result in having to turn the water off for days (while you feel your way through the process) are not such a good idea. The work can also be quite strenuous.
    Because plumbing for water is fairly simple in principle, with fairly low risk factors involved, many people ‘have a go’. The plumbing in older homes and multi-occupied homes may be very difficult to follow as a result. There are numerous books on the market which describe simple procedures, and the plumbers’ supply shop may be able to advise you. What neither of these can take into account are the idiosyncrasies of your existing plumbing.
    If money and the cost of plumbing work are your main worry, do-it-yourself plumbing might be the answer. You may save money simply by understanding what you are asking a plumber to do—how much work it is and the sort of material costs involved. You may make his job quicker if you have already identified a problem before he arrives. If you attempt a difficult job and get in a mess, it may cost you more to have a plumber sort it out.
    Remember that several special tools are required. Some homes have virtually no tools at all. Do you want to buy an adjustable spanner or a pipe bender for one job? Borrowing or hiring tools is a possibility.
     

WATER SUPPLY
     
    Urban water supplies come from many sources—rivers, wells, reservoirs and underground springs. All of it is processed to offer safe drinking water to the public, despite the fact that much of it is used for washing, flushing toilets and other things for which pure water is not necessary.
    Modern demands for water are putting increasingly heavy demands on supplies, especially in times of drought. Processing is costly and uses up valuable energy resources. Economy in use is therefore a first priority in reducing pressure on the environment and on the pocket.

Pure water?
     
    Water treatment is a very complicated business, involving settlement tanks, filtration beds and the addition of chemicals. Most water authorities prefer the water going into the mains to be slightly alkaline—in order not to corrode the system. To ensure this, lime is added, but only at about 20 parts per million. Other chemicals are used too, like ferrous sulphate to make impurities cling together so that they can be filtered out more easily (about 18 parts per million).
    A small amount of chlorine (about 5.5 parts per million) is used to kill off bacteria which may be present. By the time the water leaves the treatment plant, the level of chlorine will have been reduced to less than one part per million.
    Most chemicals added to water, such as the chlorine or copper from your own pipework, may affect the taste, but are harmless at the concentrations at which they occur.
    Other chemicals, which are known to be present in some supplies, are far from harmless. These include: Aluminium: Sometimes added during water treatment. May be carried into reservoirs from the soil. May be naturally present. Links are being considered with Alzheimer’s disease (premature senility). Water is unlikely to be a major source of aluminium—but it has been suggested that water-borne aluminium is in a readily absorbed form.
    Nitrates: Increase the risk of a rare blood disease which affects bottle-fed babies (whose feed is made up with tap water). Suspected (not yet proven) link with cancer. Leached into supplies from fertilizers and manure in intensive farming. Very difficult to remove.
    Lead: Most likely source is your own plumbing. Old pipework was made of lead (see panel). Very serious. Can damage the brain and nervous system, cause anaemia and affect the