Matsya Purana — The Ārdrānandakarī Tṛtīyā Vrata: Ritual Procedure
तिलोदकं च संप्राश्य स्वपेन्मार्गशिरादिषु मासेषु पक्षद्वितयं प्राशनं समुदाहृतम् //
tilodakaṃ ca saṃprāśya svapenmārgaśirādiṣu māseṣu pakṣadvitayaṃ prāśanaṃ samudāhṛtam //
Having duly sipped sesame-water (tilodaka), one should observe the prescribed regimen in the months beginning with Mārgaśīrṣa; this intake (prāśana) is declared to be performed for two fortnights.
This verse is not about pralaya; it prescribes a vrata-style purification practice involving tilodaka and a two-fortnight observance tied to specific months.
It supports dharmic discipline: a householder (and by extension a king who models public dharma) follows timed vows and purificatory intakes, especially in auspicious months, to maintain ritual purity and merit.
The significance is ritual, not architectural: it specifies prāśana (ritual sipping/consumption) of tilodaka and the duration—two fortnights—during months beginning with Mārgaśīrṣa.