Rivers seem to have their own, like Ganga. But what about wells, springs, streams and lakes in general? Who are their protectors? How would one go about showing gratitude for the existence of - for example - a well or spring.?
It has to be Lord Varuna, who rules over water, water bodies and even the aquatic animals.
On an auspicious day one should place a pitcher, in the West, covered with a blue cloth and decorated with blue garlands. (9)
On it one should place, in a copper vessel, the image of the deity Varuna ,the god of water, the lord of aquatic animals, made of gold, six Nishkas in weight. (10)
Satatapa Smriti, Chapter 5.
Similarly from the Manu Smriti, we find:
5.96. A king is an incarnation of the eight guardian deities of the world, the Moon, the Fire, the Sun, the Wind, Indra, the Lords of wealth and water (Kubera and Varuna), and Yama.
9.244. Having thrown such a fine into the water, let him offer it to Varuna, or let him bestow it on a learned and virtuous Brahmana.
The last verse says that anything that is offered to water goes to Varuna.
The Lord of all the water bodies is Lord Varuna. He is glorified in the Vedas too. It is mentioned in the Mahabharata Sabha Parva Chapter 9. Sage Narada gives the description of the celestial assembly of Lord Varuna to Yudhishtira.
Owned by Varuna, that delightful assembly house of pure white consists of many rooms and is furnished with many seats. There sitteth Varuna attired in celestial robe, decked in celestial ornaments and jewels, with his queen, adorned with celestial scents and besmeared with paste of celestial fragrance. The Adityas wait upon and worship the illustrious Varuna, the lord of the waters.
All the water bodies are present in the assembly of Varuna in their personified form and worship illustrious deity Varuna.
And, O king, there are also the four oceans, the river Bhagirathee, the Kalindi, the Vidisa, the Venwa, the Narmada of rapid current; the Vipasa, the Satadu, the Chandrabhaga, the Saraswati; the Iravati, the Vitasta, the Sindhu, the Devanadi; the Godavari, the Krishnavenwa and that queen of rivers the Kaveri; the Kimpuna, the Visalya and the river Vaitarani also; the Tritiya, the Jeshthila, and the great Sone (Soane); the Charmanwati and the great river Parnasa; the Sarayu, the Varavatya, and that queen of rivers the Langali, the Karatoya, the Atreyi, the red Mahanada, the Laghanti, the Gomati, the Sandhya, and also the Trisrotasi--these and other rivers which are all sacred and are world-renowned places of pilgrimage, as also other rivers and sacred waters and lakes and wells and springs, and tanks, large or small, in their personified form, O Bharata, wait upon and worship the lord Varuna.
As you can see in the second paragraph, it is clear that all the water bodies large or small are under the control of Lord Varuna and worship him. So, you can pay your gratitude by worshipping him.
You can also worship Lord Vishnu. He is said to be the lord of waters in the three worlds. Sage Narada asked the same question to Brahma. Brahma replied like this:
- Vishnu is praised in all the worlds as the deity of water. Vishnu would do good to him who is purified by water. [Padma Purana Srishti Khanda Chapter 49]