Abstract:
Water is a valuable, limited and non-renewable natural resource. Water deficiency may occur in future due to climate change as Pakistan is said to be the climate hit country in the world. Thus, efficient use of water resource is the need of the time. Lahore Branch Canal (LBC) is the source of fresh water for Lahore city and some areas of Kasur district. LBC starts from BRBD link canal and its tail is near Rore in Kasur district. This canal was primarily designed to supply water for crop husbandry in its vicinity. Besides, it also serves some other purposes in like ground water recharge etc. Its efficiency with the help of GIS and RS was investigated over last one decade from 2007 to 2017 in this study. Cultivated area reduction from 2007 to 2017 due to urban sprawl and respected irrigation water requirement (IWR) for that cultivated land were calculated using Landsat images to see the efficiency of LBC. To check the reduction in crop area, one images for one selected year were taken with five-year gap from 2007 to 2017. For IWR, two images for one selected year were taken with three-year gap from 2007 to 2017, classification of images was done and area was calculated from the classified images. Results revealed that water entering in the canal is almost same from 2007 to 2017 with minor seasonal fluctuations, however, crop area has declined continuously over last decade. An overall cultivated area reduction of 5 percent was noticed from 2008 to 2013 and 6 percent from 2013 to 2017. Built up area also increased 3 percent from 2008 to 2011, 4 percent from 2011 to 2015 and 6 percent from 2015 to 2017. For IWR cropped area is reduced 3 percent from 2008 to 2011, 4 percent from 2011 to 2015 and 6 percent from 2015 to 2017. Thus, a water surplus of 22, 23, 23 and 23 percent in the years 2008, 2011, 2015 and 2017, respectively, was found being diverted into this canal. Findings of this study suggest that this surplus quantity could be saved if not diverted into this canal and be utilized for some other area wherever required.
