Matsya Purana — Rite and Layout for Consecrating Ponds
कूपवापीषु सर्वासु तथा पुष्करिणीषु च एष एव विधिर्दृष्टः प्रतिष्ठासु तथैव च //
kūpavāpīṣu sarvāsu tathā puṣkariṇīṣu ca eṣa eva vidhirdṛṣṭaḥ pratiṣṭhāsu tathaiva ca //
In all wells and stepwells, and likewise in lotus-ponds (tanks), this very same procedure is prescribed; and in consecrations (pratiṣṭhā) as well, it is to be applied in the same manner.
This verse does not address pralaya directly; it focuses on applying an established ritual/construction procedure uniformly to waterworks and consecration rites.
It supports the dharmic duty of commissioning and maintaining public utilities—wells, stepwells, and tanks—while ensuring they are established through proper rites, a key responsibility in Puranic governance and household merit.
The key point is procedural standardization: the same vidhi (prescribed method) used in consecrations is to be followed for constructing/establishing wells, stepwells, and ponds—linking Vastu practice with pratiṣṭhā ritual.