Evaluation of SWC measures and bio-physical indicators of Kadwanchi watershed, Maharashtra, India

Abstract

The watershed development programme (WDP) is being implemented in India to enhance groundwater table, crop productivity, and socio-economic status. Impact assessment of WDP is essential for addressing key issues. Also, monitoring and evaluating the impact of soil and water conservation (SWC) measures undertaken in watersheds is required. The study was conducted at Kadwanchi watershed in Jalna district, Maharashtra, to evaluate SWC measures and assess various performance indicators. The SWC measures were implemented between 1996 and 2000 under the Indo-German WDP. Various SWC measures, viz., continuous contour trenches (CCTs), farm bunds (FBs), cement nalabunds (CNBs), earthen nalabunds (ENBs) and loose boulder structures (LBSs), were selected for the study. This study aims to evaluate the change in dimensions of SWC measures and to assess the impact of WDP on bio-physical indicators of the Kadwanchi watershed. Structural changes, silt deposition, and water storage at SWC measures were periodically monitored and estimated. The SWC measures implemented in the Kadwanchi watershed effectively arrested silt upstream, reducing soil erosion, as observed in pre- and post-development stages. Various performance indicators such as crop productivity index (CPI), cropland utilisation index (CLUI), crop diversification index (CDI) and induced watershed eco-index (IWEI) were studied. The values of CPI (increased by 87%), CLUI (increased by 81.81%) and CDI (increased by 65.68%) improved significantly due to the WDP. The IWEI index for all three seasons was assessed and observed to be 0.04, 0.35, and 0.41 for the kharif, rabi and summer seasons, respectively. An annual IWEI of 0.27 in the Kadwanchi watershed indicated rehabilitation of the remaining area through green vegetation. This study provides insight into the scientific impact evaluation of SWC measures undertaken through the WDP, highlighting their efficacy in enhancing biophysical indicators, promoting sustainable watershed management, and serving as a replicable model for future developmental projects.