StudentShare solutions
Triangle menu

Storm Drainage Design Project and Flooding - Assignment Example

Not dowloaded yet

Extract of sample
Storm Drainage Design Project and Flooding

Surface streams and groundwater flows and the wetness of soil before a the storm are the factors to be considered. According to Dr Tim Stott, rainfall prediction is a matter of statistics. No one can predict what the rainfall and catchment conditions will be in the future. With climate change, past records are not reliable for future references. Engineering design will be based on specified probability storm and the runoff generated by catchments
In the hydrographs of Cynon River, there was an almost steady flow of water in the river for the first 40 hours. As the height of water start to rise on the 42nd hour, water had a abrupt rise and on the 44th hour the water temporarily had a constant flow and began rising again on the 48th hour. The rise was constantly rising until it reached the peak flow and it was recorded to be 0.65m above the river bed and the rainfall recorded at 1.2mm. In the analyses of the river hydrograph, the rise of water is faster than when it starts to subside. It would take more time to subside, and having a steady downward motion. There are factors that control the shape of hydrographs. The typical shape are shown and the main components are labeled according to Weyman (1975). A hydrograph would show the difference between the peak rainfall from the peak discharge. This is known as the lag time. Then a lag time is greater, there is less chance of flooding whereas a short lag time will show that water had reached the river channel quickly. The rise in discharge or rainfall as shown in the graph is called the rising limb and the decrease in rainfall is the falling limb.
There are several factors that affect a flood hydrograph. Areas with large basins receive more precipitation that the small ones and they have a larger run-off(Hoyt, 1936) Larger basins will have a longer lag time as water has a longer distance to travel before it can reach the river trunk. According to Gillesania, 2006, the shape of the basin which is typically elongated, would produce a lower peak flow and longer lag time than a circular one. The effect of the slope is also very important. The flow will be faster down a steep slope, thus producing a steeper rising limb and shorter lag time.

Channel design

Given Data Note: Given the discharge in the channel, apply the the Manning
Q = 1.5 m3/s formula to get a suitable breadth b, of a channel with
n = 0.019 depth d
S = 1/2500 = 0.0004
d = 0.6
Formula to be used
V = where: v = velocity
Q = Av R = Hydraulic Radius
Q = A S = slope
A = bd n = Manning's coefficient

R = Q = discharge

Computations:
A = db
= 0.6(b)
Q = A
R =
1.5 = 0.6b
1.5(0.019) = 0.6b
0.0285 = 0.6b
= 0.6
1.425 = 0.6
=
2.375 =
(2.375)3 = b3
13.3964 =
13.3964 =
13.3964(1.44 + 2.4b + b2) = 0.36b5
19.2908 + 32.1513b + 13.3964b2 = 0.36b5
19.2908 + 32.1513b + 13.3964b2 - 0.36b5 = 0
b = 3.9798 m.

The discharge flow of the river is also to be computed. The computation is necessary because a comparison will have to be made in order to determine ...Show more

Summary

The study of storm events in rivers are used to gather information. Actual rainfall data and data from flow gauging stations are made available for the recording of actual flooding events. Data gathered are often sparse, however theoretical calculations of a runoff into the rivers are usually limited in accuracy…
Author : mayerreyes
Storm Drainage Design Project and Flooding essay example
Read Text Preview
Save Your Time for More Important Things
Let us write or edit the assignment on your topic
"Storm Drainage Design Project and Flooding"
with a personal 20% discount.
Grab the best paper

Related Essays

Design Project in UK
Though the architectural requirements are taken for consideration, this does not take in the other parameters like the overall appeal and the personal design preferences on the look of the structure from the client. The engineering aspects alone are considered in this report.
8 pages (2000 words) Assignment
Storm Drainage Design
Thus the rivers that have relatively short lag time respond very quickly to rainfall and hence can be considered as more prone to rainfall than those with larger lag time. The inflow into the river after the rainfall is through different ways. The major types are overland flow which represents the surface flows which includes other direct flows into the river.
11 pages (2750 words) Assignment
Storm Drainage Design Project Assignment
Normally, line graph is used to present discharge in over time and a bar graph is usually used to plot rainfall with time. There are factors that control the shapes of a hydrograph. Weyman. (1975) included in his statement that the different shapes are shown in a hydrograph and the main components are labelled accordingly.
6 pages (1500 words) Assignment
Storm Drainage Design Project - Scientific methods
As a matter of fact, the majority of disasters are somehow related to water. Floods, storms, hails, tsunamis, rise in the water of oceans and a host of other global events are brought about through the destructive action of water. This project composes the discussion on the studies that have been made in the conduct of rivers, particularly on the use of storm hydrographs.
6 pages (1500 words) Assignment
Storm Drainage Design Project
Weyman. (1975) concluded that the different shapes are shown and the main components are labelled accordingly. Peak rainfall and peak discharge are two different graphs. Lag time is the term for the difference betseen the peak rainfall from the peak discharge.
6 pages (1500 words) Assignment
Storm Drainage Design Project Master Assignment
It is fascinating to note that the birth of civilizations came about in riversides. From the Nile River in Egypt to the Yangtze River in China, settlements began to be established by reason of sustainability. Rivers brought forth the creation of floodplains through the erosion of sediments from higher elevations and their deposition in the river's vicinity forming a fertile area suitable for agriculture.
6 pages (1500 words) Assignment
WSUD
The water that is left on the surface is called surface runoff. The water from these sources is eventually carried away into the surface waters. Rivers, lakes, oceans and streams are all examples of surface water. Due to the presence of pollutants that
4 pages (1000 words) Assignment
Interrupting Flooding
They also require implementation and maintenance of the rain gardens. The land surveyors limit the implementation of the design related to sizing and siting
2 pages (500 words) Assignment
Highway engineering 1 (civil)
The upgrade also has both underground and above services for the area. In the early 1920s, a demand for an arterial road that linked Auckland’s west and central suburbs was needed. The
6 pages (1500 words) Assignment
Design project
There are also different methods that used in air compression. The air delivery or compression release is also different and measured in cubic feet per minute. The efficiency of an air compressor depends on the horsepower of a respective compressor. The company has an
3 pages (750 words) Assignment
Get a custom paper written
by a pro under your requirements!
Win a special DISCOUNT!
Put in your e-mail and click the button with your lucky finger
Your email
YOUR PRIZE:
Apply my DISCOUNT
Comments (0)
Rate this paper:
Thank you! Your comment has been sent and will be posted after moderation