Q:

How to help birds with water?

In India, the monsoon lasts for 4 months between June and September. Since last week or so the rain is gone, and this monsoon hasn't been decent, the rainfall had been it's lowest since the 1970's and we are already facing a water-scarcity. The temperature has already reached 38 oC.   
I have seen birds hovering over waters sources in the cities, starting from winter. Outside the town, birds get water through streams and other water bodies. In India, at the beginning of summer, starting from February people keep water in dishes and bowls for birds in the city.
While this weather change is not encouraging at all, I am so sure that I'll see thirsty birds hovering over water sources in cities sooner than usual. 

What are the best possible ways to provide water to birds by means of keeping in a dish/bowl so that many of them can make most out of it? I plan to do that in my balcony and terrace. 

A:

Providing water for birds in summer is always a brilliant idea, not just to drink but for them to have a nice bath in!
Usually bird baths are actually kind of shallow, or rather the edges usually are dipping gently into a deeper pool in the middle. This kind of dish on a balcony would suffice. 
Our multipurpose bird feeder came with a rather small waterbowl. About 8 inches diameter and 1 inch deep, this does suffice as well and I have seen birds drink from it but never bathe. I think this is due to the fact it's got vertical edges.
There is a slight issue with leaving water out in so far as the hotter it gets the faster it will evaporate and therefore in a sense it will be a waste (taking into account a water shortage). 
You can also get water drinkers though. These act exactly like a chickens water bowl, and should still suit most birds. 

You can make these with an old plastic bottle and a small plate, the idea being that water feeds onto the plate slowly but the majority is held in the bottle. These from experience can hang or be on the ground.

A:

You've already received excellent advice, so I'll just describe a few things we've been doing for years. Our bird baths are a distance from the house, so in addition to those, we provide water on the patio just outside the door, as you're planning to do on your balcony and terrace. 
For drinking, we put out shallow saucers. A convenient choice is the saucer a potted plant sits on. Some are plastic, others are ceramic, and some are just heavy-duty paper plates from the supermarket. We use a lot because, although the small birds share well, the larger types seem to prefer their own. Chipmunks and squirrels enjoy them too. (If you haven't had a close-up view of a chip or squirrel sucking up water while holding the dish with their tiny feet, you've missed something awesome! Of course, I don't know if you even have those where you live!) 
For bathing, a favorite of our birds is a plastic tray I use to start seedlings. It's a few inches deep; enough for the small birds to drink and bathe but not deep enough to drown. Anything like that would work. My picture on the left was taken during birdy play-time! I apologize that it's messy, but if you press on it, you'll get a larger view of them. It's too bad I don't have a video; they make a fun splashing sound!  We also have a plastic bird feeder with a dome above it. It doesn't work for bathing, but the birds drink from it, and it offers a little bit of protection from the weather. It's the one from which the cardinal is eating in my picture below.
In the United States, we have the opposite problem of those who deal with evaporation. During the cold winter months, our water quickly becomes little blocks of ice. Every day, sometimes twice, we dump those out and refill the dishes with warm water. Rather than bringing in all my containers, I fill up a watering can, or any pitcher I have lying around, step outside and tend to them all at once. It's quick and easy! My caution for those in colder climates is that glass dishes tend to crack in the winter, leaving jagged edges which aren't safe for the birds. Plastic can crack too, but doesn't usually break apart.
Whether it's too hot or too cold, there are times when birds rely on us for their survival, and I applaud your desire to help them! 
 

A:

We used to use a metal garbage can lid with a brick in it on top of a piece of wide pipe. I'm not sure if that's an option for you because of the size for your balcony. But, the birds loved it because they could take a bath in addition to getting a drink. Of course, we had to clean it out regularly. But, we didn't mind.
It's great that you're looking out for the birds like that.

