Almost any health information resource has the same recommendation about water: You should drink about eight glasses (64 ounces) per day [source: Mayo Clinic]. That adds up to 2 gallons per day for a family of four. When your water comes from 12-ounce plastic bottles, the cost can be exorbitant. Let's assume you pay approximately $6 per case of water (and remember, fancy imported waters can be much more), which is equal to $0.40 per bottle. For a family of four, that amounts to an annual cost of:
$0.40 per bottle x 5.3 bottles per person = $2.13 x 4 people = $8.53 x 365 (days in a year) = $3,114.67
Now let's compare that to the cost of using a water filter. There are many different types of water filters, but for simplicity, we'll use the basic pitcher-style system, which retails for about $20 and requires a new filter every 40 gallons [source: Brita]. A family of four will need to replace its water filter 18.25 times per year at a cost of about $6.50 per filter, which amounts to $119. A couple of $12 water bottles for each member of the family will run $96 per year. There is also the cost of water from the tap to consider, which runs about $1.50 per 1,000 gallons in the U.S. A family of four consumes about 730 gallons of water per year (2 gallons/day, 365 days/year), which amounts to $1.10. So, the total cost of using a pitcher-style water filtration system per year for a family of four is:
$119 (filters) + $96 (water bottles) + $20 (pitcher) + $1.10 (water from the tap) = $236.10
That means a family of four can potentially save $3,114.67- $236.10 = $2,878.57 each year by switching from bottled water to a water filter. And when you consider that most tap water is safe to drink in the U.S., you can save an additional $235 per year by skipping bottles and filters entirely, bringing the total annual drinking water cost for a family of four down to just $1.10. However, differences in water may occur when you consider that some municipal supplies do not meet standards of safety and quality, and others may contain foul odors and smells while still testing at safe levels for consumption. In that case, filtering your water is a good idea. Read on to learn about the various types of water filter systems.