It depends on the variety of the lily. There are some small ones - ask your supplier what he has that will suit the pond you have.

As above, many many different varieties suitable for a huge range of depths and spreads.

I agree with the two answers , a water lily for all depths its just making sure you get the right one you want and in all colours , so pick a colour then look at water depth in the nursery's on line , but I would wait till spring before buying one, wrong time of year to be planting PLUS THE GOOD NURSERY WONT BE SELLING ANY STOCK .

Gg

In Odisha it may still be possible to plant tropical species and hybrids, though waiting until spring may still be better. My tropical hybrid in a large water pot is still blooming, here in the low desert.

Gg, I would tend to disagree with the 'good nursery' bit, as all my stock is outdoors, hardy, and won't mind minimal disturbance, and the water's still fairly warm down here in Hants. However, the temperature's probably irrelevant as the question would appear to be coming from India, and that all depends on variety.
What would be exciting is the thought of growing some of the exotic species, Victoria cruziana or V. amazonica (annual or short-lived perennial), which require 15 degrees C or more.

Except this pond is in India not the UK...

lol silly me !!!! I forget on here its not all UK gardeners.

Hortum as in already established growing in a mesh pot and moving from A to B.

Gg

To be a little more useful to the question, some of the miniature varieties can go in as little as 20 cm of water, while most standard kinds prefer 50 to 100 cm. Giant species, such as the Victorias, don't seem to need much more depth, but do need a huge surface area.

Sorry Hortum, we seemed to have crossed - wouldn't have added my comment if I 'd seen yours.

thanks all, the comments are informative and useful.