ASSESSMENT OF NAGAVALI RIVER WATER QUALITY IN AND AROUND SRIKAKULAM DISTRICT FOR AGRICULTURE AND IRRIGATION

Abstract

In the Srikakulam district, river water is a crucial supply of irrigation water for agricultural farming operations. Changes in the physicochemical composition of agricultural soil will be influenced by river water quality, and these changes may have a vital impact on crop yields. Water samples were taken from the Nagavali River during the pre and post-monsoon seasons of 2021 to evaluate their appropriateness for irrigation and drinking and using several indices such as SAR, SSP, PI, and MH examined for different criteria. Monitoring river water quality is essential for encouraging sustainable development in agricultural regions and providing critical data for irrigation water management for agricultural production. All sampling stations are of good quality in both seasons according to the WQI values. Piper trilinear diagrams indicate that in two seasons the majority of samples were in the mixed zone (Ca-Mg-So4-Cl), and others were magnesium-bicarbonate type. The Principal Components (PCs) for both seasons were judged to clarify 74.78% of the total change in the pre-season and 81.98 % in the post-season. Both seasons' variables are entirely hydrochemical and are assumed to be the result of geological processes, suggesting geogenic origins. Ca2+ and Mg2+ do not react similarly in soil systems when used for irrigation, because Mg2+ degrades soil structure, particularly in Na-dominated and extremely salty waters. A high Mg concentration in irrigated soils often promotes the development of exchangeable Na. In the Nagavali river, Mg Hazard was found to be less than 50 in 50% of pre-monsoon samples, in post-monsoon 40% were fewer than 50. A magnesium hazard of less than 50 is appropriate in Irrigation waters. Except for the Magnesium hazard, river water quality for irrigation needs varied from acceptable to outstanding in each location.