Water

Pure and Simple

Anna Kohn, eco options, Fall 2007

Aptly called the source of life, water is essential to our bodies.  It transports nutrients and oxygen to our cells.  It moistens our tissues.  It cushions our joints and protects our vital organs.  Small wonder we're advised to drink eight glasses' worth every day. 

But, of course, the water filling those glasses ought to be pure, clean and healthy.

Water purifiers are definitely the best route to make sure you have just that in your home.  These days, purification systems in North American houses are almost de rigueur, and for good reasons.  No one wants to be inadvertently guzzling - brace yourself - bacteria, viruses, moulds, algae, yeast, lead, pesticides, live parasites and more.  Plus using a water filter means you don't have to buy bottled water any more, which saves money and the planet (fewer plastic bottles that end up as landfill).

UV SYSTEMS

UV systems are designed to purify microbiological contamination from water, in urban homes or at cottages

• They can be installed where the water enters your home, right by the water meter next to the shut-off valve, and will purify the water for your entire home.  A smaller, more affordable system can be installed under the counter.

• UV systems work by using special mercury-vapour lamps that shine UV light of a particular wavelength at the water.  The germicidal

Core (DNA) of bacteria and viruses, destroying their ability to function and reproduce.  No micro-organisms are known to be resistant to UV rays.

• Core (DNA) of bacteria and viruses, destroying their ability to function and reproduce.  No micro-organisms are known to be resistant to UV rays.

• The cost of these systems ranges from $400 (for small, under-the-counter models) to $1,200

• They are energy efficient – they require about the same amount of energy as a 60-watt light bulb running continuously for a year.  An electronic power supply accurately maintains lamp intensity during power fluctuations, meaning purification won’t be disrupted.  And maintenance is simple:  just changing the bulb and cleaning the quartz sleeve  once a year.  

• They destroy 99.99% of harmful micro-organisms without adding chemicals or changing the water’s taste or odour, and they produce no chemical by products

• They are not harmful to plumbing or septic systems

• However, UV systems don’t get rid of chlorine, VOCs, lead and other chemical contaminants and impurities, so some type of activated charcoal filtering is also needed to work in conjunction with the system

• However, UV systems don’t get rid of chlorine, VOCs, lead and other chemical contaminants and impurities, so some type of activated charcoal filtering is also needed to work in conjunction with the system.

UNDER-THE-SINK SINGLE-STAGE CARBON FILTERS

Single-stage carbon filters produce similar results to dual-stage carbon filters.  They are meant for families with three or fewer people, and can purify 750 gallons (2,840 L) of water before the filter needs to be replaced, on average about every six months.  Separate faucets are optional for this system.

UNDER-THE-SINK-DUAL-STAGE CARBON FILTERS

• This system has two carbon filters that can purify up to 1,200 gallons (4,500 L) of water, meeting the needs of a family need to be replaced.  Replacement filters can run from $25 to $60.

• The system comes with a separate faucet, but there’s no need to buy a new sink.  Just use an existing soap-dispenser or spray bottle or spray-attachment hole, or drill a new hole to accommodate the additional faucet.  The extra tap – which comes in various shapes and sizes to accommodate different sinks – allows you to use filtered water only when necessary (not for washing dishes, for example), which saves on filter use.

• With the right filters, you can expect a reduction of between 97% and 99.99% in asbestos, chlorine, parasites, lead, lindane (a pesticide that can be found in water), cloudiness from impurities and VOCs such as chlorine and ammonia.  Municipalities often use these chemicals to clean water, but they become volatile (and move into the air) when they are heated. 

FAUCET-MOUNTED CHARCOAL FILTERS

• Depending on the quality of the filter purchased, the filter purchased, these systems can reduce chlorine by 98%, parasites by 99% and cloudiness from impurities by 99%

• They are also very affordable, generally costing from $40 to $70

• Energy efficient.

• Easy and effortless:  your clean water for pitchers, bottles and cooking is literally on tap.

• Filters last anywhere from about one to three months, and cost about $10 to replace.

• The mounted system can extend lower than your tap, and if your faucet isn’t high to begin with, it’ll be tricky washing big pots in the sink.

• Faucet-mounted systems have a flow-restrictor built into them, which reduces flow to about half a gallon (2 L) per minute – that’s down from 1 ½ gallons (6.5 L) per minute with a full flowing, unfiltered tap.  While the flow restrictor is necessary to allow sufficient contact time between the water and the carbon, it does make for slow-running water.

CARBON ACTIVATED CHARCOAL

These systems work especially well in urban areas or regions where water comes from a treatment plant.  But charcoal is not recommended for water drawn from a well, rivers or lakes – if bacteria are in the water, they could breed in the filter.

Charcoal adsorbs impurities as the water passes over its surface area, and it removes many toxins found in the environment.  The systems are energy efficient, simple to install and relatively economical.

 However, charcoal systems don’t remove sediment or particulate material very well, so they often include a sediment filter.  In general they’re also not effective in removing contaminants such as microbes, sodium, nitrates and heavy metals, unless specifically indicated by the manufacturer.  Removing these would require either a reverse-osmosis water-filter system – which can use up to five gallons (22 L) of water to purify just one gallon (4.5L) – or a water distiller.  Distillation systems are effective, but they’ve fallen out of favor, mostly because the initial equipment can cost up to $2,000, they use a lot of electricity and they’re slow – they can take four or five hours to purify one gallon (4.5 L) of water.  They also remove everything from the water, including healthy natural minerals.