Due to urbanization, there is an increase in the impervious surface and in peak runoff volumes. In the past, there is significant damage caused by urban floods. Urban floods are becoming more frequent disasters in recent decades due to rapid changes in Land Use and Land Cover. In this study, we compare the impact of land-use changes on peak runoff and timing for the last three decades using the PCSWMM model for the semi-urban clusters in South India. Further, we analyze the effect of future development on peak runoff. It was observed that there is a considerable increase in flood peak (82.49%) when compared to the last decade. We proposed and evaluated alternate methods under future land use (2040) using LID wherein different scenarios were generated and tested. To evaluate the changes in hydrological characteristics, three scenarios at a regional scale were explored. The first scenario is the present situation. The second one is the traditional urban development scenario and the third one is urban development with LID controls. The model simulation results confirmed the effectiveness in reducing the surface runoff depth, peak flow rate, total flood volume, and earlier peak times using LIDs.

Soil erosion is the most common type of land degradation, and it has become a global environmental issue that reduces soil productivity and water quality. LULC change related with climatic and geomorphologic states of the area affects land degradation. This study aims at estimating the annual average soil erosion for the study area, Nagavali River Basin, and also focuses to analyze the impact of land use land cover change on the annual average soil erosion rates of the Nagavali river basin. In this study, the soil properties, elevation, and topography of the study are considered to be constant. This study was done by using the Revised Universal Soil Loss Equation (RUSLE) model. This equation includes factors like rainfall, soil, land cover, cultivation practices, and slope, for the estimation of soil erosion. Each layer of the factors affecting soil erosion was prepared and integrated using GIS techniques. By using the RUSLE model, the present study identified that the soil erosion rates for the years 1990 and 2020 ranged from 0 - 2364.46 t/ha/yr and 0 - 7857.21 t/ha/yr respectively for the Nagavali river basin. The LULC change analysis for the years 1990 and 2020 revealed that the erosion rate increased from 2364.46 t/ha/yr to 7857.21 t/ha/yr in the Nagavali river basin. The results also depicted that the area under very severe erosion class increased drastically from 1990 to 2020 while the area under very slight erosion class decreased from 1990 to 2020. This shows that LULC change has a significant impact on increase of soil erosion rates in Nagavali River Basin.