Storm Drainage Design Project, Flood Hydrographs Essay

Storm Drainage Design Project, Flood Hydrographs - Essay Example In addition hydrograph also carries information of base flow, which is the initial flow condition of the river existing in river prior to any storm. The base lag refers to the time repose of the river with respect to a rainfall which signifies the drainage potential of the catchments. The time interval between the peak rainfall the time of occurrence of peak discharge is reported as the basin lag. The rivers with short basin lag are more prone to floods as the respond very quickly to rainfall and hence the discharge in the river increases tremendously sooner the catchment receives a rainfall. The two major component of the runoff from the catchment that contributes to the volume of water in the river are the surface flow, which includes all the flows through the surface of the river and sub surface flow component which incorporates all the ground water flow discharges into the river after the onset of a storm. The slow rise is the level of river flow depth signified the majority of v olume reaching the river as ground water flow. The properly constructed hydrograph would be able to considerable amount of information of the behaviour of drainage basin with respect to a rainfall. ... The flood hydrograph for river Cynon is prepared by plotting he discharge through the river along the Y-axis and the time along x-axis. In order to plot the rainfall distribution, the depth of rainfall is plotted along a secondary y axis with time along the x - axis. The hydrograph hence plotted is shown in figure 1 and provides the detailed information on the drainage characteristics of the basin. The reports available have said that the subsurface conditions of the river Cynon basin is low permeability soil that could result in low infiltration rates. Thus these conditions would result in high surface runoff rates to the river and as a result the depth of flow rapidly rises. Thus the hydrograph obtained have steep rising limb followed by early peak discharge levels. Further, the receding limb is less steep than the rising limb justifies the discussions presented earlier. Also, the lag time is estimated from the hydrological observations as 20 hours. The flood volume of the river is computed from the total volume of the water in river during the period of runoff, by multiplying the depth of flow in the river with the mean river width given as 15 m and the average river velocity given as 4 m/s. The discharge computation from the hydrograph is as given below Particulars of computation Equation Calculation Discharge computed for the rising limb Velocity Depth of flow in river (for the rising limb) width of flow 4 m/s 0.48 m 15 m = 29.1 m3/sec Peak discharge Velocity Depth of flow in river (for peak discharge) width of flow 4 m/s 0.658 m 15 m = 39.48 m3/sec Discharge computed for receding limb Velocity Depth of flow in river (for the rising limb) width of flow 4 m/s 0.34 m 15 m = 20.4 m3/sec Total area of the catchment for the river Cynon From records

Response to The Omnivore's Dilemma Essay Example | Topics and Well Written Essays - 1000 words

Response to The Omnivore's Dilemma - Essay Example Because of these extensive choices, dilemmas are arising in the human’s minds regarding how food items are produced, whether naturally or artificially, whether unethical practices are followed, in total dilemma of what food to eat. â€Å"When you can eat just about anything nature has to offer, deciding what you should eat will inevitably stir anxiety† (Pollan 3). So, the main intent of the author, Michael Pollan is to provide the readers with an overview of the production process of various food choices, so the readers can select the apt foods, they want to consume. To learn for himself, and also to inform the readers about the production processes and thereby about food choices, Pollan follows the food chains of the three major food categories, which provide us the food– industrial food, organic food, and foraging food. That is, he examines the food chains of these three food categories from the initial till it reaches the humans stage (factory production and s upermarkets in the case of Industrial food, agricultural farms, small scale producers and vendors in the case of organic food and finally hunting expedition in case of foraging). â€Å"To this end, he embarks on four separate eating adventures, each of which starts at the very beginning — in the soil from which the raw materials of his dinners will emerge — and ends with a cooked, finished meal.† (Kamp 2006). The other main intent of Pollan is bring into focus how corn plant has came to dominate majority of the food choices in the American diet, and so allocates sizable portion of the book (close to 7 chapters) discussing about it. Although, corn is a benign plant, which is grown in large numbers throughout America and consumed directly in minimal quantities, it is actively used in the production of various food items, food additives, preservatives, etc. That is, after corn is produced, it is milled or refined or recompounded, and then it could â€Å"become any number of things, from ethanol for the gas tank to dozens of edible, if not nutritious, products, like the thickener in a milkshake, the hydrogenated oil in margarine, the modified cornstarch,†¦the ubiquitous sweetener known as high-fructose corn syrup (HFCS).† (Kamp 2006). With such extensive ‘applications’, Corn plant production is crucial to the survival and functioning of the various food industries. Because of which, the industrial food industry is implementing various dubious and unethical production practices to produce corn in a large scale manner. With heightened production, the corn has become cheap and plentiful, with Pollan even stating that it has become a â€Å"remarkably inexpensive industrial raw material.† (Kamp 2006). As a result, Pollan argues, food is much cheaper and more plentiful than it used to be, but unfortunately the health of the humans and that of the environment has deteriorated. Pollan also had the intent to bring out th e negatives of the organic food industry as well. Although, the organic industry mainly produces environment friendly and healthy foods for the people to consume, the production process in that industry also has started bordering on commercialization. That is, producers are adopting many of the methods of the industrial fo