Longitudinal and monsoon-seasonal variations in trophic state indices based on total phosphorus (TSI (TP)), Secchi depth (TSI (SD)), and CHL-a (TSI (CHL-a) for overall (a–c), drought, and flood years (d–i). Seasons were categorized as premonsoon (Pre), monsoon (Mon), and postmonsoon (Post). The trophic status was classified as oligotrophic (Oligo), mesotrophic (Meso), eutrophic (Eu), and hypereutrophic (Hyper).