Matsya Purana — Glory of Tīrtha-Śrāddha: Best Times
तथा च सरयूः पुण्या सर्वदेवनमस्कृता इरावती नदी तद्वत् पितृतीर्थाधिवासिनी //
tathā ca sarayūḥ puṇyā sarvadevanamaskṛtā irāvatī nadī tadvat pitṛtīrthādhivāsinī //
Likewise, the Sarayū is holy and revered by all the gods; and so too is the river Irāvatī, as though abiding in the sacred ford (tīrtha) dedicated to the Pitṛs, the ancestral spirits.
This verse is not about Pralaya; it belongs to a tirtha-mahātmya context, emphasizing the sanctity of rivers and their power to confer merit through association with divine and ancestral sacred sites.
It supports the householder duty of honoring gods and ancestors: visiting holy rivers and performing Pitṛ-related rites (such as śrāddha and tarpaṇa) at Pitṛ-tīrthas is presented as especially meritorious.
The ritual significance is primary: Sarayū and Irāvatī are highlighted as fit for worship and ancestral offerings, implying these riverbanks and fords are ideal locations for snāna (ritual bathing), tarpaṇa, and śrāddha observances.