Water Quality Simulation and Water Quality Parameters’ Scenarios in Godavari River in Maharashtra
On multiple instances over the previous ten years, the Godavari River's dissolved oxygen (DO) level has steadily decreased to zero during the dry season, making the water unfit for use as the raw water supply for Nasik town. The main factor contributing to the river's declining water quality is discharges from point sources and diffuse sources that contain contaminants with organics and nutrients. A one-dimensional steady-flow systems river water quality model, QUAL2K, was built and simulated in order to identify the factors that have an impact on the river's water quality. Seven monitoring stations' data on the Godavari River's water quality from 2011 to 2021 were used to calibrate and validate the model. Various water quality metrics were simulated during the crucial time period to compare to the specified surface water quality requirements in India. (Maximum biological oxygen demand (BOD), nitrate-nitrogen, and ammonia-nitrogen at or below 2.0, 5.0, and 0.5 mg/L, respectively; minimum dissolved oxygen at or above 4 mg/L). The river's research span extends 355 kilometres from Ramkund to the heart of Gangakhed. The study's main focus is on a few river segments where several elements have caused dissolved oxygen degradation. To evaluate the change in dissolved oxygen concentration, loads and upstream dissolved oxygen modification scenarios were run. The QUAL2Kw model's output demonstrated that improper reaeration and the breakdown of organic stuff were the main contributors to the impairment. (BOD5 and DO over 2 mg/L) Water resources managers can use the QUAL2Kw model to simulate the quality of the river's water in the present and the future and to assist them develop the best possible policy alternatives for the Godavari River.
Keywords - Water Quality Model, Qual2k, Godavari River, Diffuse Resources, Point SOURCE.