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ThesisItem Open Access Laboratory studies on soil scour downstream of chute and stepped spillways for varying conditions of flow energy(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-01) Dheeraj Kumar; Akhilesh KumarThe study of scour downstream of hydraulic structures such as large dams, stilling basins, diversion works, underflow gates, and culverts constitutes an important field of research due to its frequent occurrence in engineering applications. The performance of a drop structure depends largely upon its capacity to dissipate the hydraulic energy of flowing water. The amount of energy dissipation is the difference between the incoming and outgoing energies and the performance of a stepped spillway is dependent on the size of its individual step at a particular drop and discharge In this study, laboratory experiments were conducted to study energy dissipation and its effect on maximum depth of scour and the amount of soil scoured considering different soil materials using a chute spillway and stepped spillway with three selected step sizes for varying discharge conditions. In all cases the total drop was kept constant. Observations were recorded for amount of energy dissipation, outflow energy, maximum scour depth and amount of soil scoured for various combinations of step size and flow rate using different soil materials. To conduct experiments the developed models were installed in the Hydrologic Simulation and Sedimentation Laboratory which is near to Soil and Water Conservation Engineering department. The amount of energy dissipated was minimum for chute spillway while in case of stepped spillway the amount of energy dissipation was found to be the maximum for step size of 2.54 cm and then decreased gradually as the step size increased for a given discharge. The maximum scour depths were found to be increasing with the increase in outflow energy of flow. On the basis of above, the maximum weight of the scoured soil was found to be increasing with the increase in outflow energy of flow. The above findings clearly indicate that scour depth and scour weight of soil downstream of a drop structure are directly related with the energy dissipation. The use of stepped spillway result in better energy dissipation and thereby resulting in lesser scour depth and scour weight.ThesisItem Open Access Sediment outflow from mulch treatments at varying land slopes under simulated rainfall conditions(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-07) Singh, Sachin Kumar; Kashyap, P.S.The problem of soil erosion in India is very serious. About 18.5% of the world’s total soil erosion takes place in India, which is about16.4tons/ha/year.Organic mulches are very effective in preventing soil erosion,reduce sediment transport rate, runoff rate and increasing infiltration. The study was carried out with the objectives to observe the sediment outflow from various mulch treatments at selected land slopes under simulated rainfall conditions by using rainfall simulator of size 10 m × 1.2 m × 0.5 m with the locally available soil material collected from College of Agriculture Business Management, Pantnagar. In the present study, paddy straw, hay and trash mulches were selected to observe the effect of mulching in soil loss reduction. The quantity of these three types of mulches were taken as, 6 ton/ha, 8 ton/ha and 10 ton/ha and for each mulch treatment, three rainfall intensities viz. 11cm/h, 13cm/h and 14.65cm/h at 0%, 2% and 4% land slopes were selected. The duration of rainfall was fixed (10 minutes) for every mulch treatment. The total runoff volume was found to be varying with different mulch rates for particular rainfall input and land slope. The runoff distribution pattern was observed to be increasing with the increase in land slope. The average sediment concentration and outflow was found to be increasing with the increasein land slope,but sediment concentration and outflow decreased with increasing mulch rate for particular land slope and rainfall intensity. The sediment outflow rate for no mulch treated land was higher as compared to trash mulch, hay mulch and paddy straw mulch treated lands. Mathematical relationships were developed for relating sediment outflow rate, sediment concentration,land slope and rainfall intensity for a particular mulch treatment. It was observed that values of sediment outflow rate and average sediment concentration had a good correlation with rainfall intensity and land slope for each mulch treatment. The correlation coefficients of developed models were found to be more than 90%.ThesisItem Open Access Drought analysis using different indices for Pantnagar and Dehradun areas of Uttarakhand(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-07) Ram Kumar; Anil KumarIn this present study, the annual and seasonal rainfall series of Pantnagar and Dehradun areas were analyzed using India Meteorological Department (IMD) classification of drought as mild, moderate, severe and extreme drought as per percentage rainfall deviation. Based on the drought analysis using the SPI criteria, appropriate crop planning and design of rainwater harvesting and storage structures in the drought affected areas can be proposed in drought affected areas. Standardized Precipitation Index (SPI) was calculated at different time scales (1, 3, 6, 12, and 24 months). The SPI is a drought index based on the probability of an observed precipitation deficit occurring over a given prior time period. The assessment periods considered range from 1 to 36 months. The monthly data were converted into seasonal rainfall of four month period as pre-monsoon (February to May), monsoon (June to September) and post-monsoon (October to January) and multi-temporal rainfall series with running sum for 1-month, 3-month, 6-month, 12-month and 24-month durations for both the locations. The SPI, calculated for a desired period at any location, are based on the long term precipitation record (30 years or more). The positive SPI values show greater than medium precipitation, while negative SPI values indicate less than medium precipitation. The results shows that the SPI can be used for better assessment of drought as it considers larger range of moving sums of rainfall data. Since SPI uses for the running sum of rainfall values at multi-time scales (1 to 24 months) and more variables depending on the statistical distributions used, it gives better assessment of meteorological drought at multitime scales. The 3-month SPI can be used for short term drought monitoring and agricultural crop planning and 12-month SPI can be used for long term drought monitoring and water resource planning.ThesisItem Open Access Stochastic modelling of monthly rainfall series at Pantnagar (Uttarakhand)(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-07) Navale, Manisha Madhav; Kashyap, P.S.The monthly rainfall data of 1981 to 2010 of Pantnagar were used for development of stochastic models. While the data for the year 2011 and 2012 were used for forcasting. To bring stationarity in the historical data series square root transformation was used. Fourier analysis was performed for determination of periodic component. The base period and number of significant harmonics was determined by autocorrelogram analysis and analysis of variance test respectively. Periodic component was removed by deducting from trend free series to obtain stochastic series. Stochastic series was standardised and normalised. The stochastic series was modeled by autoregressive (AR) family of Models. The Box-Pierce Portmanteau level was used to fit the test. The performance of model in regeneration and prediction of monthly rainfall value were evaluated quantitatively and qualitatively by comparison of historical and selected model correlograms and goodness of fit test such as mean forecast test, mean absolute error, root means square error. Results showed that properties propagated in the regenerated and predicted data series are similar to those of the historical series. In general, there is a good agreement between autocorrelation functions of historical and regenerated time series.ThesisItem Open Access Laboratory studies on soil scour downstream of chute and stepped spillways for varying conditions of flow energy(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-01) Dheeraj Kumar; Akhilesh KumarThe study of scour downstream of hydraulic structures such as large dams, stilling basins, diversion works, underflow gates, and culverts constitutes an important field of research due to its frequent occurrence in engineering applications. The performance of a drop structure depends largely upon its capacity to dissipate the hydraulic energy of flowing water. The amount of energy dissipation is the difference between the incoming and outgoing energies and the performance of a stepped spillway is dependent on the size of its individual step at a particular drop and discharge In this study, laboratory experiments were conducted to study energy dissipation and its effect on maximum depth of scour and the amount of soil scoured considering different soil materials using a chute spillway and stepped spillway with three selected step sizes for varying discharge conditions. In all cases the total drop was kept constant. Observations were recorded for amount of energy dissipation, outflow energy, maximum scour depth and amount of soil scoured for various combinations of step size and flow rate using different soil materials. To conduct experiments the developed models were installed in the Hydrologic Simulation and Sedimentation Laboratory which is near to Soil and Water Conservation Engineering department. The amount of energy dissipated was minimum for chute spillway while in case of stepped spillway the amount of energy dissipation was found to be the maximum for step size of 2.54 cm and then decreased gradually as the step size increased for a given discharge. The maximum scour depths were found to be increasing with the increase in outflow energy of flow. On the basis of above, the maximum weight of the scoured soil was found to be increasing with the increase in outflow energy of flow. The above findings clearly indicate that scour depth and scour weight of soil downstream of a drop structure are directly related with the energy dissipation. The use of stepped spillway result in better energy dissipation and thereby resulting in lesser scour depth and scour weight.ThesisItem Open Access Groundwater studies in lower part of Ganga-Ramganga interbasin using co-active neuro fuzzy inference system and fuzzy logic(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-06) Pradhan, Sucharita; Shiv KumarThe present study was undertaken in lower part of Ganga-Ramganga interbasin to investigate groundwater behavior, to prepare groundwater inventory for the assessment of groundwater utilization development stage and to study the comparative performance of Co-active Neuro Fuzzy Inference System and Fuzzy Logic rule based model to predict the seasonal depth to water table. Four groundwater models were developed using net groundwater recharge, net groundwater discharge and previous water table depth as input parameters in which model 1 andmodel 2 were developed using seasonal data and model 3 and model 4 were developed using annual data as input for both pre-monsoon as well as post-monsoon seasons. Neuro Solution 5.0 software with 71 % of total data having two to four Gaussian membership function was used for identification of most efficient network among 5 different CANFIS structure whereas Fuzzy Logic Toolbox with MATLAB R2010a was used to develop Fuzzy Logic rule based models. During the study period of 23 years, two hydrograph stations were on rising water table trend; eight hydrograph stations were neither on rising nor falling water table trend and nineteen hydrograph stations were found to be on falling water table trend during both pre-monsoon and post-monsoon seasons. The water table trend for rest hydrograph stations was not same during pre-monsoon and post-monsoon seasons. Numbers of minor irrigation structures like private tube wells and pump sets on bore wells along with area irrigated by different minor irrigation structures were increasing at an alarming rate. The cropping pattern revealed an increasing trend of area under high water demanding crops like rice and wheat while area under all minor crops except vegetables were found to be decreasing. The groundwater inventory indicated that during the study period, out of 25 blocks of study area, 22 blocks transformed from lower category to higher category of groundwater utilization development stage. The values of performance indicator such as R2, MAD, RMSE, CVRE, CE, r, APE and PI were calculated to evaluate the performance of CANFIS and Fuzzy Logic rule based models. Based on the values of performance indicator for CANFIS models, model 3 with CANFIS-2 structure and model 4 with CANFIS-1 structure were selected for prediction of depth to water table of pre-monsoon and post-monsoon seasons respectively. Further on the basis of values of performance indicator for Fuzzy Logic rule based models, model 3 and model 4 were selected for prediction of depth to water table of pre-monsoon and post-monsoon seasons respectively. By comparing CANFIS and Fuzzy Logic models on qualitative and quantitative basis, Fuzzy Logic rule based models were found to be better than CANFIS models. It was also concluded that, even though the results of CANFIS models were not as accurate as that of Fuzzy Logic rule base models, still CANFIS models confirmed its potential to recognize the trend of depth to water table during the period of study.ThesisItem Open Access Effect of shape and size of end sill on hydraulic energy dissipation behaviour in inclined spillway(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-06) Jaiswal, Shatruhan; Akhilesh KumarIn this study laboratory experiments were conducted to observe hydraulic energy dissipation behaviour through the formation of hydraulic jump in an inclined spillway with SAF stilling basin using different shapes and sizes of end sill for varying discharge conditions. In all cases the total drop was kept constant. The observation were recorded using different combinations of height and shapes of end sill such as rectangular end sill (RES), triangular end sill (TES), semi-circular end sill (SCES), diagonal vertical upstream end sill (DVUES) and diagonal vertical downstream end sill (DVDES). These end sills were used for three heights of 3 cm, 4 cm and 5 cm at selected discharges of 1.65 lit/sec, 4.4 lit/sec, 4.9 lit/sec and 5.5 lit/sec respectively. Required flow parameters like pre and post jump depth of flow, height of jump were experimentally observed for 60 different combinations of end sill shape, discharge and height of end sill. Based on these observations, pre and post jump flow energy was determined and accordingly amount of relative loss of energy, hydraulic jump efficiency were calculated and compared. It was observed that in case of triangular shaped end sill, the maximum relative loss of energy occurred in 07 combinations of end sill height and discharge out of total 12 combinations tried and in no case it provided the minimum energy loss. Similarly, semi- circular, rectangular and diagonal vertical downstream shaped end sill provided minimum energy loss in 4 cases out of 12 combinations tried for each while each of them provided maximum energy loss only in one case. The diagonal vertical upstream shaped end sill provided maximum and minimum relative energy loss in only one case each. It was also found that the triangular shaped end sill resulted in minimum height of jump, in general, for different combinations of height and discharge.ThesisItem Open Access Pollution assessment of river Ganga segment in Uttarakhand(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Dabral, Ashish; Kashyap, P.S.Soil erosion due to rain and wind action is a serious problem in India. Its negative impacts include reduction in soil productivity, silting of dams and reservoirs, deficits in water availability, pollution of water courses, serious damages to properties by soil-laden runoff, and desertification of natural environments. In the present study, chemical and physical parameters of the river were observed. The river Ganga segment in Uttarakhand was taken as study area from Devprayag (30.140N, 78.590E) to Balawali (29.640N, 78.10E). From the study area, a total of twelve locations were selected and water samples were taken in February and June. The classification of the locations of the samples of both the months for the utilization of water for various purposes like drinking water source without conventional treatment but after disinfection, fish culture and wild life propagation and irrigation and industrial cooling or controlled waste disposal was done for useful interpretation of which water could be used for what purposes according to desirable and permissible limits of pH, EC, TDS, free CO2, chloride, total acidity, calcium hardness, total hardness and magnesium hardness.ThesisItem Open Access Simulation of runoff and sediment yield from a hilly watershed using Soil and Water Assessment Tool (SWAT) and Wavelet Neural Network (WNN) models(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Jillani, Asima; Anil Kumar