Reducing the estimated 38 billion plastic water bottles discarded each year will obviously have a huge environmental impact. Those environmental benefits may be leading this effort to switch from bottled water to tap water, but the finances of making the change should also not be overlooked.

Cindy Crawford has joined the effort by teaming up with PUR Water Filtration Systems (PUR) to promote a limited edition Thirsty for Change water bottle. The aluminum water bottle is manufactured and sold by SIGG, the Swiss Engineered Water Bottle company. The idea is to reuse the bottle and fill it with filtered tap water instead of buying bottled water. The Thirsty for Change website claims that PUR filtered water is 1/10 the cost of bottled water, which will save an average of $600 per year. Filtered tap water is being promoted because PUR is the co-sponsor of the initiative but depending on where you live, you may be able to drink unfiltered tap water to save even more.

Any reusable bottle will allow you to make this change, but if you order the limited edition Thirsty for Change water bottle, all proceeds from the sale will benefit Procter & Gamble’s Children’s Safe Drinking Water Program, which helps reduce water-related disease in many developing countries around the world.

Personally, I use a Nalgene bottle that cost about $10 less than the SIGG bottle.