Bhagavatapurana 3.33.32

3.33.32

tasyās tad yoga-vidhuta- mārtyaṃ martyam abhūt sarit /
srotasāṃ pravarā saumya siddhidā siddha-sevitā //

32. And her mortal body of which the mortal dross had been burnt up by her Yoga became transformed into a river; and that river superior to many others, O gentle Vidura, is resorted to by the Siddhas and confers Siddhi or the light of wisdom (upon those that bathe in it.)