Water Treatment

[ll_billym]

Can someone explain exactly how the water system works and it's future? 

We get relatively pure (i.e. drinkable) water from our taps but people are pouring bleach, urine contaminated with drugs, faeces, detergents, and all manner of contaminents into our drains.  Can someone explain how this is filtered out, especially chemical compounds, to be made into drinkable water again.  Surely every time the water is passed through the system it becomes more contaminated, when will our water be unfit for drinking or even washing with?

[Tim Baxter]

Two pronged attack here.  First it is filtered through sand and/or gravel to get rid of the gross contaminants, e.g. large particles.  This cannot remove chemicals but (I imagine) the pollution is reduced usually by the sheer volume if water which the chemical has combined with.

After all the crud has been filtered out a chemical like chlorine will be added to kill off any bacteria.

Check out Goooogle for further info.

[Headtime]

The redoubtable Wikipedia comes up trumps again, with this link;

http://en.wikipedia.org/wiki/Water_purification

Explaining possibly more than anyone could dever possibly want to know about the above topic.

Hope this helps

[doctorsteve]

Tap water is extracted from rivers, lakes or bore holes.  Foul or used water is discharged to a treatment plant eg sewage works or discharged directly into the sea. When it has been treated it is often discharged to a river only to be reused down the line.  There is a measurable build up in residues of chemical eg phosphates and drugs or hormones the more people the water has been used by.  The whole system is fed by rainwater filling the lakes etc, basically distilled water with all the added chemicals that are in the atmosphere.  The water board cannot economically remove all contaminants from water and instead have allowable limits.  In my opinon most tap water is perfectly safe in comparison to the rest of the crud we absorb in a day from the enviroment and food etc.  But if given the option move to a mountain and only drink spring water!!

[Gef]

By evaporation.

[Tim Baxter]

Further to my answer and contrary to previous posts no drinking water is drawn direct from rivers and lakes in the UK.  It is always drawn from reservoirs fed from bore holes and natural drainage.  It is always treated before being pumped for consumption.

There is huge alarm at the moment because 'oestrogen mimicking chemicals' are found in large concentrations at outflows to river where domestic 'foul' but treated water is discharged.  This is causing lower animal life (fish and reptiles) to exhibit exagerated female characteristics.  That is, if being born male, the animal exhibits female genitalia also.  And we wonder why the human male sperm count is dropping!!!!  Very worrying.