आपो जनयथा च नः।

आपो हि  ष्ठा मयो भुवस्ता न ऊर्जे दधातन।
 महे रणाय चक्षसे।
यो वः शिवतमो रसस्तस्य भाजयतेऽह नः।
 उशतीरिव मातरः। तस्मा अरम् गमाम वो यस्य क्षयाय जिन्वथ।
 आपो जनयथा च नः।
महानारायणोपनिषत्
āpo hi  ṣṭā mayo bhuvastā na ūrje dadhātana|
 mahe raṇāya cakṣase|
yo vaḥ śivatamo rasastasya bhājayate'ha naḥ|
 uśatīriva mātaraḥ|
 tasmā aram gamāma vo yasya kṣayāya jinvatha|
āpo janayathā ca naḥ|
mahānārāyaṇopaniṣat
The waters are indeed conferring upon us bliss of life. 
 Such waters, please do bless us with food and great insight into the supreme truth.  Oh waters, make us also the participants in this life itself  of the joy of yours which is most auspicious just like the fond mothers who feed their beloved children with nourishing elixir of breastmillk. 
Oh waters give us permission to enter into your abode satisfactorily with your gracious blessings.
 During our sojourn this earth , you the deities of waters, please generate for us the nectar of yours  for sustenance of our life and enjoyment of our pleasures.

This veda chant is found with slight variations in rg and yajur vedas themselves.  Our forefathers were never miserly in being grateful to the natural forces.  
The importance of the water was well known to them and therefore water was considered  as divinity/
This is also part of pavamaana sooktha which is chanted as punyahavaachanam and waters purified with the manthra are supporsed to grant purity to all things on earth.
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