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Methods of Sediment Control Sediment entering a canal can be controlled in a variety of ways. A large storage reservoir built on the stream automatically traps all coarser fractions of sediment and a large percentage of finer fractions.  A canal supplied from such a reservoir will therefore have water which is free from sediment. While such a reservoir is s constructed across nonperennial streams, the development on perennial rivers normally s usually envisages the construction of a low weir or a barrage to control the water level and divert the flow into the canal.  Figure shows the typical headworks used on perennial streams in India. It consists of a weir or a barrage, river training works, scouring sluices (also called undersluices), divide wall, fish ladder and canal head regulator.  The lake upstream of such barrages does not trap much sediment load and the canal is likely to be heavily charged with sediment. However, attempts are usually made to locate and construct the headwork

IMPORTANCE OF GEOMETRIC DESIGN   The geometric design of a highway deals with the dimensions and layout of visible features of the highway such as alignment, sight distances and intersections. The geometrics of highway should be designed to provide optimum efficiency in traffic operations with maximum safety at reasonable cost. The designer may be exposed to either planning of new highway net work or improvement of existing highways to meet the requirements of the existing and the anticipated traffic. It is possible to design and construct the pavement of a road in stages; but it is very expensive and rather difficult to improve the geometric elements of a road in stages at a later date. Therefore it is important to plan and design the geometric features of the road during the initial alignment itself taking into consideration the future growth of traffic flow and possibility of the road being upgraded to a higher category or to a higher design speed standard at a later stage. Geometri

Table Of Contents WHAT IS LINEAR PROGRAMMING? Linear Programming (LP) is a mathematical modelling technique useful for economic allocation of 'scarce' or 'limited resources, such as labour, material, machine, time, warehouse space, capital, energy, etc., to several competing activities, such as products, services, jobs, new equipment, projects, etc., on the basis of a given criterion of optimality. The phrase scarce resources means resources that are not in infinite in availability during the planning period. The criterion of optimality, generally is either performance, return on investment, profit, cost, utility, time, distance, etc. The word linear refers to linear relationship among variables in a model. Thus, a given change in one variable will always cause a resulting proportional change in another variable. For example, doubling the investment on a certain project will exactly double the rate of return. The word programming refers to modelling and sol

Table Of Contents GRAPHICAL METHOD For LP problems that have only two variables, it is possible that the entire set of feasible solutions can be displayed graphically by plotting linear constraints on a graph paper to locate the best (optimal) solution. The technique used to identify the optimal solution is called the graphical solution approach. IMPORTANT DEFINITIONS:  1) Solution: The set of values of decision variables  x j   (j = 1, 2, ..., n) which satisfy the constraints of an LP problem is said to constitute solution to that LP problem. 2) Feasible solution:  The set of values of decision variables  x j  (j = 1, 2, ..., n) which satisfy all the constraints and non-negativity conditions of an LP problem simultaneously is said to constitute the feasible solution to that LP problem. 3) Infeasible solution: The set of values of decision variables  x j  (j = 1, 2, ..., n) which do not satisfy all the constraints and non-negativity conditions of an LP problem simul

GROUND WATER HYDROLOGY -NUMERICALS   Numerical 1: In an area of 22km², the water table dropped by 3m. If the porosity is 30% and the specific retention is 14% , Determine (i) the specific yield of the aquifer and (ii) change in ground water storage. Numerical 2: A field test for permeability consists in observing the time required for a tracer to travel between two observation wells. A tracer was found to take 10 h to travel between two wells 50 m apart when the difference in the water-surface elevation in them was 0.5 m. The mean particle size of the aquifer was 1mm and the porosity of the medium 0.3. If v=0.01 cm²/s estimate (a) the coefficient of permeability and intrinsic permeability of the aquifer, and (b) the Reynolds number of the flow. Numerical 3: An artesian aquifer 20 m thick has a porosity of 20% and bulk modulus of compression 10^8 N/m² and Bulk modulus of Elasticity of water is 2.1 * 10^9 N/m². Estimate the storage coefficient of the aquifer. Numerical 4: A 30 cm well co