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The Sukhna Lake of Chandigarh City is a man-made lake situated in the foothills of the Shivalik range in the north-east corner of the city. This urban lake is one of the prime tourist places of the 'City Beautiful' and is mainly used for recreational purposes like boating, morning and evening strolls, exercises, food plaza and sightseeing. The catchment of the lake is mainly hilly and erosion prone, with the Sukhna wildlife sanctuary comprising a major portion of it. The water quality index of the lake water and its dependence on catchment characteristics has been studied. By using the National Sanitation Foundation Water Quality Index (NSFWQI) and Overall Index of Pollution (OIP), the results of the water quality assessment have found the lake water as having 'good' and 'acceptable' quality respectively based on past seven years' data. During the last few years, construction activities in the catchment area have speeded up and a few invasive alien plant species have come up in the lake. Inflow of untreated domestic waste water from nearby villages in the catchment, particularly during the rainy season, seems to be the main reason for the weed problem in the lake. Strict enforcement of ban on new construction activities and preventing the release of untreated domestic waste water from the villages located in the catchment are the absolute necessary steps for maintaining and improving the lake water quality.

The Rock Mass Rating (RMR), Geological Strength Index (GSI) and kinematic analysis are widely employed in geotechnical engineering practice. The RMR and GSI both are used for rock mass characterization while the kinematic analysis is applied to identify the mode of failure of slope based on rock discontinuities and slope face characteristics of rock. An attempt has been made to analyze the RMR, GSI and Kinematic Analysis using in-situ data corresponding to Vindhyan sandstone. The data has been collected from outcrops at seven different locations in and around Markundi hill along SH-5, Chopan, Sonbhadra. The relationship between RMR and GSI for Vindhyan sandstone in the study area has been attempted using generalize equation proposed by Hoek (2013) while the kinematic analysis has been applied to decipher the weak zone of failure using RocScience Dips software. The lowest RMR value estimated is 35 for location S-4 and the highest RMR value is 58 for location S-1. Other locations viz, S-2, S-3, S-5, S-6 and S-7 have the RMR value from 42 to 49 which infers that the Vindhyan sandstone existing at Markundi is characterized by both poor as well as fair rock mass. The GSI value of the location S-1 is estimated as 34 (minimum) and 46 (maximum) of location S-4. GSI value of the same rock formation also corroborates that the rock mass belongs to poor as well as fair rock mass. The wedge failure is inferred due to intersection of two sets of joints oriented in north-west and north-east direction. The line of intersections of these two discontinuities are observed in wedge shaped block. It is concluded that the locations under investigations have tendency of wedge failure.

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Stability of the slopes along the rock cut on hilly roads are a major concern because slope failures lead to disruption of traffic and loss of property/life. The Markundi hill near Chopan, District Sonbhadra is characterized by moderate strength and highly jointed rock with rugged topographic features has experienced several episodes of rockfall activities. This geological phenomenon disturbs the traffic on SH-5 which is lifeline to eastern U.P., parts of M.P., Bihar and Jharkhand States of India. An attempt has been made to assess the present geotechnical condition of the rock mass and demarcate the nature and locations of possible failure using rock mass characterization techniques and kinematic analysis. On the basis of RMR values, section-1 and section-2 having poor to fair quality rock mass while on the basis of SMR investigation, section-1 and section-2 falls in partially stable to unstable class, respectively. Kinematic analysis suggests that slopes are unstable and wedge failures are commonly observed along both left and right slope sections.