Matsya Purana — Design and Splendour of Tripura: Maya’s Threefold Moving Fortress
सप्ताष्टदशभौमानि सत्कृतानि मयेन च बहुध्वजपताकानि स्रग्दामालंकृतानि च //
saptāṣṭadaśabhaumāni satkṛtāni mayena ca bahudhvajapatākāni sragdāmālaṃkṛtāni ca //
And I too had them properly prepared—seventeen ground-level structures (or platforms), set out with many flags and pennants, and adorned with garlands and festoons.
This verse is not about Pralaya; it focuses on auspicious preparation and ornamentation of earthly arrangements (platforms/structures) using flags and garlands.
It reflects the duty to conduct public or sacred works with proper honor and auspicious presentation—maintaining order, cleanliness, and dignified decoration for rituals, festivals, or consecrations.
It highlights standard Puranic/Vastu-adjacent markers of sanctity and celebration—dhvaja-patākā (banners) and srag-dāma (garlands/festoons)—used to consecrate and visually designate prepared platforms or structures.