Spatiotemporal Analysis of Waterbodies in Ranchi District, Jharkhand using Satellite Data: An Input for Jal Shakti Abhiyan

Abstract

Keeping in the view of water conservation the Government of India has initiated the Jal Shakti Abhiyan, which needs the inventory of waterbodies for further planning and monitoring. Lakes and Ponds in year 2005 and year 2018 were mapped in Ranchi district at 1:5000 scale using high resolution satellite data and reservoirs at 1:50,000 scale using moderate resolution satellite data. Seasonal fluctuation in water extent of reservoirs was estimated using Pre- monsoon and post-monsoon satellite data. Total number of lakes and ponds mapped in Ranchi district in year 2005 and year 2018 were 2170 and 2556, respectively. Total area under lakes and ponds was 1425 ha and 1618 ha, respectively in year 2005 and year 2018, which was 0.29% and 0.32% of total geographical area of Ranchi district. A total of 19 and 20 reservoirs mapped in Ranchi district in year 2006-07 and year 2018-19, respectively. Area recorded under reservoir category in Ranchi district was 2854 ha and 2829 ha in pre-monsoon season in the year 2007 and 2019, respectively. In Post-monsoon season the area occupied by reservoirs was 3428 ha and 3352 ha in Year 2007 and 2018, respectively. It has been suggested to undertake large scale mapping of lakes and ponds at 1:500/1000 scale using seasonal satellite data for preparation of inventory and estimation of pre and post-monsoon variation in number and area of lakes and ponds. Maps and statistics generated in present study are useful for planning, monitoring and management of waterbodies in present scenario of urbanization, environmental degradation and climate change.

Keywords: High resolution data, urbanization, pre-monsoon, post-monsoon, lakes and ponds