ASSESSMENT OF WATER RESOURCES AND DEVELOPMENT OF WATER RESOURCE MANAGEMENT PLAN FOR POTHAKAMURU WATERSHED
Loading...
Files
Date
2022-11-09
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
guntur
Abstract
Water requirement has been increasing by 1% since 1980. Over two billion people live in countries experiencing high water stress. Water stress is not a factor that solely depends on water availability. At the same time it depends on the management of available resources. Watershed based study is considered as the best way to manage water resources properly. The study was conducted on Pothakamuru watershed of Darsi Mandal in Prakasam District. Prakasam District is one of the drought affected districts in coastal Andhra Pradesh. A number of soil and water conservation works has done on this watershed from 2012 to 2018. So that Pothakamuru watershed has been selected for fulfilling following objectives. i) To assess surface and groundwater resources and estimate the water demand for agricultural sector of Pothakamuru watershed. ii) To develop sustainable water resources plan for the watershed using appropriate optimization techniques. iii) To assess the impact of soil conservation measures on crops and water bodies.
DEM of the study area was downloaded for the generation of watershed boundary, drainage lines, drainage area and slope map of watershed. The watershed comprises an area of 12952.85 ha with a population of 54599 people. The farmers on the watershed mainly depend on groundwater for irrigation. The surface waterbody on the watershed comprises an area of 574.68 ha. The watershed has a stream having a water spread area of 198.96 ha. LISS III data of 2012 and 2018 were downloaded from BHUVAN website, for the generation of LULC map and NDVI map. Sentinel 2 satellite image from USGS Earth Explorer was used for the extraction of agricultural areas on different agricultural seasons of the hydrological year 2017-2018. Total agricultural water demand was estimated by adding the crop water requirement and livestock water demand. The crop water demand of the study was estimated from Modis ET data product( MOD16A2) by the extraction of crop area. Livestock water demand was obtained from livestock
population. Total water demand for the agricultural sector was obtained as 21.14Mm3 for the year 2017-2018 where crop water requirement is obtained as 20.7Mm3 and livestock water demand is found to be 0.44Mm3. Water requirement for the domestic sector is obtained as 1.09Mm3.
Hydrological soil group map and LULC map were made in for the estimation of runoff. Highest percentage of of soil came under the category of moderately high runoff potential. The runoff from the watershed was estimated using SCS Curve number method. Out of 572.4 mm of average rainfall, 151.41 mm of water was going as runoff from the watershed which is 26.45% of the total precipitation. This runoff joins into the surface water resources. Drainage map of the watershed was obtained from SRTM DEM file.the study has drainage order four. Drainage density of watershed was obtained and drainage density map was generated. Runoff map of the watershed was prepared in ArcMAP. Runoff coefficient for the entire watershed was obtained as 0.3. Runoff coefficient map was generated with the help of the GIS platform.
Most of the soil and water conservation measures on the study area were concentrated on the upstream side of the watershed. A better water resource management plan was needed for the study area. Water resource management plan for the study area was adopted from decision rules which are separate for water conservation structures and soil conservation measures. Soil conservation measures were adopted by considering LULC and slope of the study area. Water conservation measures were adopted by considering slope, drainage order and runoff potential of the area. Contour bunding, grassed water way, farm ponds, silt application, drainage disposals, forest restoration and crop plantation were the soil conservation measures selected. Farm ponds, percolation ponds, gully plugs and subsurface dykes were the water conservation structures adopted for the watershed. Decision rules were applied in the study area, by considering a grid of 25 ha in ArcGIS.
Soil conservation works on the watershed between 2012 to 2018 were collected. LULC map of the study area in 2012 and 2018 was prepared from LISS III satellite image. The LULC map showed a noticeable change in land use pattern. Built up area, agricultural area, plantation area and water spread area of watershed had increased. At the same time, the area of wasteland was reduced. A portion of wasteland was converted into agricultural land and plantation. NDVI maps of respective years were prepared. Area came under the category of no vegetation on 20111-2012 and decreased on 2017-18. Area came under moderate vegetation which includes agriculture and plantation on 2011-12 increased on 2017-18.
Description
ASSESSMENT OF WATER RESOURCES AND DEVELOPMENT OF WATER RESOURCE MANAGEMENT PLAN FOR POTHAKAMURU WATERSHED