Thanks very much, Usha di.and Saroj ji.
Indeed, the scene shown by third pic is very pleasing.
I had been there expecting that an entire day would be less for exploring.
In tourist map of Puducherry, there is a mention of Ousteri Wetland and National Park.
If searched on internet, there is lot of promising substance written about the wetland and national park.
But the project never seemed to have seen taken up by governments of Tamil Nadu and Pondicherry.
Other than this old, very large, man-made lake, there is nothing to admire.
Besides the thin scrub around the lake's periphery, there is no much scope for botanizing (having national park in mind).
Perhaps, birders may find it good - only if they have exceptionally good zoom lens.
Regards.
Dinesh