21.  Some sewerage authorities do purify water, but after that process the water is not drinkable or even usable for agriculture or landscaping, she said.

22.  That is why cross-flow filtration has become popular for many processes, like purifying water and making beverages.

23.  The additional water will come mostly from treated urban runoff, and it remains to be seen how successfully that water can be purified.

24.  The life raft he carries onboard includes a device for purifying salt water.

25.  The Olympic fountains actually purify water from a nearby polluted stream, as do buffer strips of toxin-filtering plants.

26.  The new greenhouse could include tanks of fish and plants that thrive on nitrates and purify water that can be recycled through the garden.

27.  The safest bottled water has been purified by distillation or reverse osmosis.

28.  The water will be purified naturally in waste-water landscapes using gravel and plants.

29.  They will be used to purify the water used for cooking for the American soldiers and for an Army hospital being built in Bosnia.

30.  And water suppliers need to continuously search for better ways to purify the water.