Of course, restraunts should charge for water

Some restaurants charge for a cup of water. Well, its about time. We pay nothing for a cup of water but about 2 bucks for soda and the only difference is a small bit of flavoring. Why should we expect others to subsidize our choice of drink? Of course we should be charged for water.

Some of the costs involved
Water from the local water utility.
Glass or cup
Sometimes lemon
Soap (and water) to wash the glass
Who should pay those expenses? Somebody certainly will. Those that buy the other drinks? Should they pay for someone else's 'free' water? Should the restraunt donate a drink to some customers, but not others?
It seems very reasonable that the water-drinking customer should help cover the costs for these items. It just seems fair.

Charging for a glass or cup of water is:
Economically appropriate.
Eco-conscious: discourages water and materials waste.

The water fee
In the examples above, the charges ranged from 20¢ to 50¢. That seems reasonable. Enough to not be a burden, but enough to offset the costs.

Implementation of the water charge
Since water would be a purchased item:
The server should no longer automatically bring water for everyone at the table. That would be an unauthorized charge. The customer would need to request water, like any other drink.
There could be table tents explaining the logic and fairness of the new policy.
The option of water would be listed with other drinks in the menu.
An individual restraunt would, understandably, be hesitant to charge for water if its competitors don't. One key to successful implementation is for an entire group of restraunts to add the charge. This could be an association, like national, state, city, or community restraunt groups:

From a Food Blog: Why do European restaurants charge for tap water?
Because it's not free. It costs to wash the glass, then there's the ice used, electricity, the dish machine, and the water billed by the month as a utility; the server cost money to pour it, deliver it, and clean up after. In all restaurants there are the unrecoverable expenses caused by just having a person walk in the door. Things like toilet paper, soap, paper towels, rags used to wipe the table they sat at - even if all they had was a glass of water. All these things add up. Those are courtesies, but, the cup/glass of water is a tangible consumable that is part of the meal as is tea, coffee, or soda. The fact is, water isn't free.