I. “Knowledge demands some kind of access to a fact on the part of some living subject. Without a mind to access it, whatever is stored in libraries and databases won’t be knowledge, but just ink marks and electronic traces.”
This one would classify as theory since it makes claims which can be tested and thus also be taken as false or true. This specific quote plays with the notion that knowledge can be acquired and lost. Yet, knowledge has greater importance to us than water and gold. Because the exitance of gold will still be there after the downfall of humanity, the same cannot be said for the exitance of knowledge because this existence depends on an individual’s awareness of this so-called existence. Now, moving on to the access to this knowledge. The access to this knowledge may or may not be unique to an individual or collective, a fact might be known by one person but not by another. Knowledge will always belong to an individual or a collective, yet the knowledge of the collective may go beyond the knowledge of the individual. At times, the actuality of a fact is based on the fact that every member of a certain group knows this, i.e. the orchestra knows how to play a Beethoven piece, despite each individual member only knowing how to play their part. Also, a collective can combine their knowledge in remarkable ways to use their member’s individual knowledge to solve a problem. Scholars within this field start with the basis of one individual’s knowledge to create their hypothesis or book. Later, this before mentioned book will try to define the knowledge taking place in the link between a person and a fact. So, one can say that knowledge can only be realised when the subject and object enter into a relation. This relation is based on three principles:
I. Knowledge is the result of the union of subject and object.
II. The object known is in the knowing subject according to the nature of the knower
III. The perfection of knowledge is in proportion to the immateriality if the knowing subject. In short, knowledge can only exist in the presence of a subject. Therefore, the union of knower and known is essential.
So, in order for there to be an object, there needs to be a subject. Further, if one wants to confirm that knowledge exists, one needs a somewhat physical manifestation, i.e. libraries or database to make this known. Because if one does not have this physical manifestation of knowledge. Identified through one’s sense, it will only be ink in paper or electronic traces. In continuation of this we have this interesting statement:
II. “The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.”
This one would classify as a truism since it is deemed true and has nothing new to inform us of. Two great men are cited as saying this to warn humanity to be aware of how flawed the illusion of knowledge can be. The first is a celebrated American historian by the name of Daniel J. Boorstin and the other is the late great Stephen Hawking, a world-renowned British cosmologist. The last part of this statement draws parallels to the Marxist notion of “a little knowledge is a dangerous thing.” Further, Mr Hawking is right in his prediction that ‘the greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.’ Mr Hawking is widely acclaimed for his aphorism and his work within the field of cosmology. The main purpose of his remark is to warn us about the shortcomings of ‘the illusion of knowledge’ as it is. In short, an illusion of knowledge is one’s faulty, unscientific, unproven, vague, false, misleading approach or assumption of situation, facts or information. For instance, recently a black Yale student, by the name of Lolade Siyonbola, had the campus police called on her for simply napping in the common area of her dorm. The white student, Sarah Braasch, who did this assumed that Lolade was some sort of threat and presided to contact the police. After the police are called and arrive the situation quickly escalates, and she ends up having a 15-minute discussion about her right to be at this great institution. And, this is not the first time this white student has called the campus police on a black fellow student. About three months earlier she called the campus on a black male student, quiescently this was one of Miss Siyonbola, for simply standing in a stairwell. In both cases, Miss Braasch makes the assumption that these fellow black scholars pose some form of threat. Further, this assumption is probably based on how African Americans are portrayed in the media, here they are often seen as being violent, unpredictable and generally a threat. So, based on this the white female student jumped to the conclusion that both these African Americans are seen as a treat to her security. Apparently, African Americans are not allowed to be accomplished either, Siyonbola has a major in computer science and a minor in Spanish but the white mentally unstable female student do not seem to know this or even ask how Siyonbola has come to nap at the common area. In present day, on is engrossed in superficial knowledge that one seldom makes the attempt the understand oneself. The current trend of being ‘connected’ all the time has created a space where one is bombarded with information so often that one so not take the time to assess this ‘knowledge’ down to the minute detail. The result is that one takes in this ‘knowledge’ but do not attempt to give it further thought. This superficial knowledge gives one the impression that one is all knowing. Yet, in reality one rarely does one’s research and rarely check if the facts are true by using former experience based on existing knowledge. This creates a space where the illusion of knowledge can thrive, and this illusion makes humanity oh-so arrogant. Another important factor is that only a privileged few take the time to reference sources. This can be boiled down to the fact that one listens less and talk more, thus less listening leads to the growth of this illusion.
Nowadays, second hand-knowledge is thrown at us constantly. In this era of ‘recycled knowledge’ one is being fed with all kind of messages, be it ‘spam’ or politician’s election manifesto, one feels it is more of a hindrance than a help. Therefore, this second-hand knowledge seems to block our own thoughts and thus one feels unjustified in believing this information. Because as Nagel suggests “knowledge demands some kind of access to a fact,” but in this post factual one does not know what to believe. Knowledge is distinct from information, although both consists of true statements, however, knowledge is information with a purpose. From the assortment of information hurled at us, one needs one’s individual mental ‘filters’ to separate the wheat from the chaff. Further knowledge can be granted or withheld, shared or kept secret, and amounts to a source of power in either of these cases. But then there is the ‘illusion of knowledge’ where one does not have a complete knowledge of the task at hand. In continuation of this, the ‘illusion of knowledge’ may come about because knowledge has been withheld as a form of social control. For instance, take the God men and Shamens, who claimed that they used their ‘superior’ knowledge to enslave people. They did this by carefully controlling the information they gave their subjects or in other words appealing their subject’s conscience. According to Plato, this persuasion is the key to gaining power. Thus, knowledge can be used as a tool to take advantage of certain situations, where one group or individual has more knowledge than their opponent. Nevertheless, this knowledge is a way for individuals to define society and examine its progression and what has caused this progression. Moreover, sciences are being fundamentally revised, one can even state that Newton waited for Einstein or Darwin, so he himself could be challenged and eventually grow. The above-mentioned examples are the result of knowledge, its application and its widespread circulation. In short, worldviews are challenged on the daily by the vast amount of knowledge that exists. And yet, the most oft-discussed question is still whether God exists or not or if what is written in the bible is just a well-crafted narrative or something that actually happened. Therefore, knowledge is a source that must be harnessed. And learning is just a perfect illustration of knowledge put to good use or in some cases horrible application. Knowledge is power as many says, this power can be found everywhere and is just waiting to be used productively to empower the powerless. Or as it is famously said “seek and you shall find.”
Within epistemology, the knower and the known or “knowledge demands some kind of access to a fact on the part of some living subject” will be classified as subjectivity. As early as the 17th c., scientists have repeatedly argued that in order for knowledge to be true it has to be ‘objective’ rather than ‘subjective.’ When the ‘objective’ real knowledge is obtained it is the role of the knower to realise his limitations and try to achieve the position of the scientific observer. Further, the consequence of this split between the ‘outer’ and the ‘inner’ world has led to an evidence-based conception of nature. This way of understanding one’s surroundings has reduced these same surroundings to nothing but fragments of one’s mind. Yet, philosophers, such as Kant and Hume, questions this view of the natural world. Hume see the self as something that can be achieved through experience or “a unique identity of a person over time.” On the contrary, Kant argue that one knows oneself through a combination of rationality and experimentation or through activity. Yet, one can help to be formed by one’s environment (i.e. family, society, time). Despite these outside factors influencing the self, the self itself, according to Kant, is some entity with “no identity, individuality, not destiny.” In contrast, Mr Hawking’s quote: ‘The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge’ would be classified as either a hypothesis or simply a truth. The hypothesis states as follows is ignorance the greatest enemy of knowledge or is it simply that of the illusion of knowledge. And, the conclusion to this would be that the ‘illusion of knowledge’ is indeed the greatest enemy of knowledge. Since only a few tend to reference their works and thus the un-trained reader will have a harder time uncovering if a certain statement is true or not because in this era of constant information it is difficult to determine if something is true or false. One could also look at it from the perspective of the JTB theory even though it is not widely used anymore. This theory states the following:
I. S believe P to be true
II. P is true
III. S is justified in believing that P is true by evidence
To explain it in detail, the JTB theory divides knowledge into three different categories. First, the belief that knowledge requires a degree of certainty. Second, the justification meaning that one needs evidence to prove this belief. Third, the truth is that the belief must, in the end, correspond with the complete truth. The JTB theory seems to be correct and can be applied to many situations. Now, let’s look at an example of this. Now, suppose that Miss Siyonbola is a threat because of the pretrial of African Americans in the media. Further, suppose that the white female student has strong evidence for the following:
I. According to the news, Miss Siyonbola is a threat because of her skin colour and thus the white female student calls the campus police
Miss Braasch’s evidence of (I) might be that because of Miss Siyonbola skin colour, she is not only a threat, but she does not belong at this prestige’s institution. And, that she has a right to call the campus police if she feels ‘threatened’. According to proposition (a), which entails:
II. The young lady sleeping on the common is a threat because of her skin colour
Let’s then suppose that the white student accepts (b) because of the evidence of (a). Thus, the white student is right in believing that (b) is true. But unbeknownst to her Miss Siyonbola is sleeping in the common room because she is writing a paper. Proposition (b) is deem true, though proposition (a) in which he based (b) is false. Thus, in the example above all the following is true:
I. S believe P to be true
II. P is true
III. S is justified in believing that P is true by evidence
But it is equally clear that Miss Braasch does not know that (b) is true; for (b) is true in virtue to the fact that Miss Siyonbola is a fellow student and a very accomplished one. Since Miss Braasch seems to unaware of this fact, and therefore basis his belief on what the news tells her to believe. This makes Miss Braasch come to the conclusion that Miss Siyonbola is a threat rather than just a fellow student being exhausted after working continuedly on her paper.
In conclusion, Mr Hawking’s statement can draw parallels to the Marxist notion of ‘a little knowledge is a dangerous thing.’ This rings true because if one does not have the full scope of the task at hand, one is thus more likely to get the illusion that one is all knowing. Also, the concept of knowledge will always be claimed by an individual or a collective. And, this knowledge is distinct from knowledge since knowledge is information with a purpose. And, this knowledge is distinct from knowledge since knowledge is information with a purpose. Information does not necessarily need a mind to exist while knowledge does need a subject to approve that said knowledge is true.

I. Theoretical Background
Flooding in urban areas is an unavoidable problem in many cities, and it causes huge costs to the society in structural and non-structural damage. The impact of urban flooding is often very difficult to evaluation precisely. The damages in urban flooding may be divided into three groups; direct damage, indirect damage, and social consequences.
A highly developed urban place results to an increase of runoff volumes and flow rates, which may cause more frequent flooding. To abate the adverse downstream effects of urban stormwater runoff most communities use flow retardation structures. Detention basins, retention basins, infiltration basins, infiltration basins, and roof top storage are some examples of flow retardation structures. A detention basin provides protection in floodplains by containing floodwater for a brief period of time. It can be constructed by damming a channel or by excavating a pond into the existing ground. The excavation of a detention basin is constructed by a combination of cut and fill.
A detention basin is a non-natural flow control structure that is used to hold flood water for a limited period of time. Detention basins are more widely used for stormwater management than any other type of control. However, at present, its primary application has been for drainage control, i.e. peak-flow attenuation, rather than the water quality control. Detention basins designed for peak flow attenuation can be given an effective water quality control function at little added cost. (The Urban Water Resources Research Council of the American Society of Civil Engineers and the Water Environment Federation)
In designing a multipurpose detention pond there are certain guidelines that must be followed to ensure that the pond is properly maintained and do not become hazardous. 1.) Side slopes should not be greater than 3m horizontal to 1m vertical. 2.) An underdrain system should be constructed to minimize the wetness of the pond bottom. 3.) An alternative to the underdrain is the sloping of the pond bottom with at least 2% grade form inlet and outlet. Another means of elimination the wetness is to slope the pond to a gutter that flows through the pond. 4.) the pond bottom and the side slope should be finished with at least four inches of topsoil and seeded. This seed or sod should be capable of withstanding periodic flooding conditions. 5.) Outlets should be provided with rip-rap protection to prohibit erosion if soil is weak. 6.) An overflow spillway or weir should be placed at the high-water elevations and a minimum of 8m (3in) of freeboard should be provided. (NIPC 1986)
According to Debo (1982), poorly sited detention ponds may cause increased flood risked due to concentrated discharge. It fails in flood control for smaller that design of the storm. A detention pond can reduce flooding if the location is properly selected A proposed detention pond must be evaluated on a site-to-site basis.

Pre-development conditions are the most accurate estimated assumptions that a certain area hasn’t undergone any adjustments since before settlement. Under this scenario assumptions for run-off should match the pre-construction conditions with the post construction conditions. Improvement of the run-off conditions can be done if the run-off management within the area is poor.

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Rational Method is an approach in designing for water shed or any small structures limited to maximum drainage of 200 acres. The rational method is applied by using a simple formula that relates runoff coefficient of a certain water shed, the rainfall intensity for a period of time and the watershed drainage area. The formula is
Q = CiAwhere:
Q = design discharge (L3/T),
C = runoff coefficient (dimensionless),
i = design rainfall intensity (L/T), and
A = watershed drainage area (L2).

TR-55 Tabular Hydrograph Method is another approach that can be used in the study. As summarized by Akan (1993), the tabular method develops multiple partial flood hydrographs at any point of the watershed. This is done by sectioning the watershed into homogeneous subareas. This method is only limited to the SCS 24-hr type I, IA, II, and III rainfall distributions. For this method the size of the drainage area, the time of concentration, the runoff curve number, and the travel time from the subarea outlet to the watershed outlet of each subarea should be known. The flow contributions of each sub area is calculated by the formula:
q = qtAmRWhere
q = discharge coming from a sub-basin at time t (cfs),
qt = tabular unit discharge at time t (cfs/mi2/in.),
Am = drainage area of subarea (mi2), and
Am = drainage area of subarea (mi2), and
According to Akan (1993), the characteristics of a detention basin can be depicted by as a stage-storage and stage-discharge (outflow) relationships. For a regular-shaped basin, the stage storage relationship can be solved geometrically. For trapezoidal detention basins that have a rectangular base of W by L and a side slope of z, the relationship between the volume (or storage) S and the flow depth d is: S = L W d + (L + W)z d2 + (4/3)z2 d3.
The detention basin outflow is dictated by the structures’ outlet type and size. The stage-discharge relationship can be obtained by the governing hydraulic equation of the structure. There are 3 common categories for the outlets for the detention basin: orifice-type, weir-type, and riser-pipe type.
According to Iowa Stormwater Management Manual an orifice by the definition is a circular or rectangular opening of a prescribed shape and size. The discharge of an orifice is geometrically controlled by the opening and the depth of submergence and is determined by the formula:
Q = ko ao (2gh)0.5
Where
Q = the orifice flow discharge (cfs)
ko = dimensionless coefficient of discharge
ao = cross-sectional area of orifice or pipe (ft2)
g = acceleration due to gravity (32.2 ft/sec2)
h = effective head on the orifice, from the center of orifice to the water surface
According to Brater and King (1976) a weir by definition is a hydraulic control structure that is commonly used in detention basin. The structure’s discharge is calculated by the general formula:
Q = Cw L (2gh)3/2
Where
Cw = dimensionless weir discharge coefficient
L = effective weir length, ft
h = water depth above the crest
According to Iowa Stormwater Management Manual a perforated riser is a special kind of orifice flow. The riser used is a vertical pipe punctured with evenly spaced holes. According to McEnroe (1988), the discharge of a perforated riser without orifice plate at the bottom is formulated as:
Q = Cs (2As/3hs) (2gh)3/2
where:
Cs = dimensionless discharge coefficient of the side holes
As = total area of the side holes, ft2
hs = length of the perforated segment of the riser pipe, ft

i. Look at a particular development/ proposal within Tasmania and consider the political, economic, social and environmental factors.

On the Picturesque East Coast of Tasmania, a gargantuan multi-million-dollar eco-resort redevelopment of a 3185-hectare Cambria Estate at Dolphin Sands north of Swansea, has become a hot rising controversial topic. The luxury resort is planned to include 70 villas, 240 units, a 120-floor luxury hotel with an organic bistro, 2 golf courses, palliative care unit, a village and an airstrip to facilitate The Royal Flying Doctor Service. The redevelopment will impact many factors:

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. Political

The main political factors in the redevelopment of the Cambria Estate is the China and Tasmania relationship as since the Australia Government has strengthened the Affiliation with the Chinese Government since the signing of a Memorandum of Understanding to increase tourism cooperation. To promote Chinese tourists to come to Australia. Also, previously with the President Xi-Jinping coming to Tasmania. The Tasmania government has chosen to target China and Hong Kong their priority markets in the Asian region for tourism. As China has become Tasmania’s largest investor. The redevelopment has been seen to heighten the relationship. Other political factors are new road improvements.

. Economic
The main economic factor is tourism. Tourism in Tasmania contributes to $2.3 Billion dollars a year, approximately around 9% the economy (Tas). Tasmania in starting to become progressively popular for visitors with 1.28 million visitors coming last year to the state. Just in the East Coast region approximately 377,600 visitors visited there. With between 2012 to 2015 there was a 281.6% increase in tourists from china. As the resort overlooks Wineglass bay it will be a huge cash cow as around 300,000 tourists visit there every year.
. Social
The social factors that the redevelopment will impact is a rise in jobs and population. With The region’s Mayor Michael Kent saying that the resort will do wonders to the community, bringing the youth back due to the growth in jobs it will bring. As the average age of the population of East Coast, Tasmania being 65. It will help rise the population, but by doing so will impact the lifestyles of the residents, who are prone to some quiet, close, small towns with little traffic.
. Environment
The redevelopment will impact the regions biodiversity as the areas around the resort provide ideal breading grounds and habitats for endangered species. The Moulting Lagoon reserve found close by above Dolphin Sands has thirteen plant species which are listed under the Threatened Species Protection Act 1995 and is also special due to the cultural heritage of Aboriginal tribes. Around the Cambria Estate in the 2km radius there have been 31 registered aboriginal sites. As the redevelopment will being large numbers of tourists, it has the risk of changing our unique, cherished wildlife and sites. By pollution, destroying of habitat and traffic.

ii. What would be the different prospective of different political parties?

As the Liberal’s ideology is conservative this means they agree highly on the private ownership of land, support and favour free enterprise and personal wealth. The Liberal’s are keen on the redevelopment knowing it will strengthen ties and trade between china. With their many cases previously when the Chinese have done political donations. For the redevelopment in Dolphin Sands the Greens have accused the Tasmanian government of agreeing and ignoring other Asian trading partners for China ahead of Tasmania’s fourth trade delegations and after the visit from President Xi-Jinping. The Greens have a different view on this slamming the proposition and saying that the increase of foreign ownership of Tasmania has starting raise concerns of food security, sovereignty and the influence of China after a Chinese Communist Party-Linked group formed with Cassey O’Conner commenting, “It’s about the strategic imperatives of the Chinese Communist Party and it’s about the importance of Australia and Tasmania making sure that the relationship is a healthy and robust and mutually respectful relationship where we stand up and we say sure, invest here. But on our terms.” Also commenting, “We will not be the useful idiots for the Chinese Communist Party. We will come into this place and defend Tasmania’s sovereignty, our food security, our way of life and our cultural identity every single day of the week.”
iii. What’s in it for the people of Tasmania?

For the residents who live in that area there are countless benefits due to the redevelopment. One of them is the Palliative care unit doctors which will help many of the residents as the closest one they have is in Hobart making it easier for terminally ill patients to live close to their homes. The redevelopment will also bring an increase of jobs to the area with the unemployed rate in Tasmania having the highest unemployed rate in 2014. It will help by bringing most of the jobs closer to where they live as many move to Launceston, Hobart or other larger ‘cities’ to work. As visitor accommodation being one of the highest employers. The tourism will also help the small businesses around the area.

iv. What’s in it for the government?
For the government it will gain a boost in economy, tourism and a firmer with China as we rely on the country for a lot. We depend on them for goods and services, in consuming and providing us manufactured goods. As Australia is a country that relies largely on foreign investment to grow. Chinese investment helps the Australia’s economy as many businesses benefit from low interest rates worldwide. This has been driven due to hefty amounts of Chinese savings which are available to lend to Australia. With the Tourism booming in Tasmania, after recent economic analysis showed there was a 17% increase in 2016-2017. It will boost local business economy, which will eventually help the government.

v. What’s in it for other stakeholders?

Stakeholders are referred as, “an individual, group, or organization, who may affect, be affected by, or perceive itself to be affected by a decision, activity, or outcome of a project” (Project Management Institute, 2013). The Stakeholders for the redevelopment project is the proposers which are the Cambria Green Agricultural Tourism Management lead by Ronald Hu and Liu Kejing. The benefits of this redevelopment for the team is that they gain a lot of wealth, investment and resources bringing power to their name and open this area up to Chinese tourists. Other stakeholders are the Chinese government, which the management team discussed with on the redevelopment. The government will gain a more secure relationship with Australia unlocking future redevelopment in our country.
vi. What issues would the government need to balance?
The Government will need to balance the issues of making sure that the redevelopment will not overpower and strain the biodiversity and wildlife of the surrounding areas. Making sure that it adheres Biodiversity and Scenic Landscape code. They will also need to still represent the population who voted them in listening to their opinions on the idea of redeveloping the estates as many residents disagree on it while balancing the strong relation with China. Without being influenced of political donations and upcoming delegations with the foreign country.
vii. How does the government deal with issues to deal with tourism. E.g. How councils are set up/ministers responsible

The government deals with issues that deal with tourism in several ways. For the proposition of redeveloping Cambria estate were that the senior executives and planning officers at Glamorgan Spring Bay Council had to secretly discuss the proposition. until the special planning area application was agreed on. After that it was voted on by the council which it won 4 to 3 to progress to the rezoning application change. But many residents of the area got mad due to rushing the proposal and not asking the publics comment on it. Later on, the council approved the rezoning allowing the proposal to begin the proposal of putting together a planning application with the final stop being the Tasmanian Planning Commission approval. If it is successful a development application will be submitted to the state government. As you can see, when a proposal is made it has to go through a variety of steps, countless polishes before it is sent to the state government.

viii. Outline the environmental impacts/ consequences concerns. How can these be managed/overcome?

The environmental impacts and concerns the develop will bring is that it will destroy historical aboriginal sites, bring pollution, impact fragile nesting areas, change lifestyle and etc. Many of these can be overcome by respecting areas and removing wastes (plastics) the right way. As this redevelopment will target foreigners it is important to educate them about our wildlife and how to take care for it, ensuring they know the do’s and don’ts. As education is the key. The local governments could also help fund some services to help protect areas which are under threat to make sure they are maintained in perfect condition and the resort should use renewable energy with smart eco-friendly building designs. The concern of a lifestyle (environment) change from a quiet town to a busy one would be unnerving for some residents who have been accustomed to the peaceful lifestyle. To overcome this is to make sure the developer takes a slow approach, gently easing the residents to be comfortable in their new environment.

I. Introduction
A. Grabber
B. Background on Andrew Jackson
C. Restatement of the Question
D. Thesis and Roadmap- Andrew Jackson was/ was not democratic because_____________1st reason, __________________ 2nd reason and ________________ 3rd reason
II. Body Paragraph Reason 1________________
A. Baby Thesis One reason Andrew Jackson was/was not democratic _________
B. Evidence- Use a document to provide 2 or 3 details
C. Argument- This evidence shows that Andrew Jackson was/was not democratic
III. Body Paragraph Reason 2________________
D. Baby Thesis One reason Andrew Jackson was/was not democratic _________
E. Evidence- Use a document to provide 2 or 3 details
F. Argument- This evidence shows that Andrew Jackson was/was not democratic
IV. Body Paragraph Reason 3________________
G. Baby Thesis One reason Andrew Jackson was/was not democratic _________
H. Evidence- Use a document to provide 2 or 3 details
I. Argument- This evidence shows that Andrew Jackson was/was not democratic
V. Conclusion- Restate your thesis
A. Summarize key ideas of your argument
B. Explain why this question is significant. Why is it important to judge whether an American President is democratic or not?

I. Theoretical Background
Flooding in urban areas is an unavoidable problem in many cities, and it causes huge costs to the society in structural and non-structural damage. The impact of urban flooding is often very difficult to evaluation precisely. The damages in urban flooding may be divided into three groups; direct damage, indirect damage, and social consequences.
A highly developed urban place results to an increase of runoff volumes and flow rates, which may cause more frequent flooding. To abate the adverse downstream effects of urban stormwater runoff most communities use flow retardation structures. Detention basins, retention basins, infiltration basins, infiltration basins, and roof top storage are some examples of flow retardation structures. A detention basin provides protection in floodplains by containing floodwater for a brief period of time. It can be constructed by damming a channel or by excavating a pond into the existing ground. The excavation of a detention basin is constructed by a combination of cut and fill.
A detention basin is a non-natural flow control structure that is used to hold flood water for a limited period of time. Detention basins are more widely used for stormwater management than any other type of control. However, at present, its primary application has been for drainage control, i.e. peak-flow attenuation, rather than the water quality control. Detention basins designed for peak flow attenuation can be given an effective water quality control function at little added cost. (The Urban Water Resources Research Council of the American Society of Civil Engineers and the Water Environment Federation)
In designing a multipurpose detention pond there are certain guidelines that must be followed to ensure that the pond is properly maintained and do not become hazardous. 1.) Side slopes should not be greater than 3m horizontal to 1m vertical. 2.) An underdrain system should be constructed to minimize the wetness of the pond bottom. 3.) An alternative to the underdrain is the sloping of the pond bottom with at least 2% grade form inlet and outlet. Another means of elimination the wetness is to slope the pond to a gutter that flows through the pond. 4.) the pond bottom and the side slope should be finished with at least four inches of topsoil and seeded. This seed or sod should be capable of withstanding periodic flooding conditions. 5.) Outlets should be provided with rip-rap protection to prohibit erosion if soil is weak. 6.) An overflow spillway or weir should be placed at the high-water elevations and a minimum of 8m (3in) of freeboard should be provided. (NIPC 1986)
According to Debo (1982), poorly sited detention ponds may cause increased flood risked due to concentrated discharge. It fails in flood control for smaller that design of the storm. A detention pond can reduce flooding if the location is properly selected A proposed detention pond must be evaluated on a site-to-site basis.

Pre-development conditions are the most accurate estimated assumptions that a certain area hasn’t undergone any adjustments since before settlement. Under this scenario assumptions for run-off should match the pre-construction conditions with the post construction conditions. Improvement of the run-off conditions can be done if the run-off management within the area is poor.

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Rational Method is an approach in designing for water shed or any small structures limited to maximum drainage of 200 acres. The rational method is applied by using a simple formula that relates runoff coefficient of a certain water shed, the rainfall intensity for a period of time and the watershed drainage area. The formula is
Q = CiAwhere:
Q = design discharge (L3/T),
C = runoff coefficient (dimensionless),
i = design rainfall intensity (L/T), and
A = watershed drainage area (L2).

TR-55 Tabular Hydrograph Method is another approach that can be used in the study. As summarized by Akan (1993), the tabular method develops multiple partial flood hydrographs at any point of the watershed. This is done by sectioning the watershed into homogeneous subareas. This method is only limited to the SCS 24-hr type I, IA, II, and III rainfall distributions. For this method the size of the drainage area, the time of concentration, the runoff curve number, and the travel time from the subarea outlet to the watershed outlet of each subarea should be known. The flow contributions of each sub area is calculated by the formula:
q = qtAmRWhere
q = discharge coming from a sub-basin at time t (cfs),
qt = tabular unit discharge at time t (cfs/mi2/in.),
Am = drainage area of subarea (mi2), and
Am = drainage area of subarea (mi2), and
According to Akan (1993), the characteristics of a detention basin can be depicted by as a stage-storage and stage-discharge (outflow) relationships. For a regular-shaped basin, the stage storage relationship can be solved geometrically. For trapezoidal detention basins that have a rectangular base of W by L and a side slope of z, the relationship between the volume (or storage) S and the flow depth d is: S = L W d + (L + W)z d2 + (4/3)z2 d3.
The detention basin outflow is dictated by the structures’ outlet type and size. The stage-discharge relationship can be obtained by the governing hydraulic equation of the structure. There are 3 common categories for the outlets for the detention basin: orifice-type, weir-type, and riser-pipe type.
According to Iowa Stormwater Management Manual an orifice by the definition is a circular or rectangular opening of a prescribed shape and size. The discharge of an orifice is geometrically controlled by the opening and the depth of submergence and is determined by the formula:
Q = ko ao (2gh)0.5
Where
Q = the orifice flow discharge (cfs)
ko = dimensionless coefficient of discharge
ao = cross-sectional area of orifice or pipe (ft2)
g = acceleration due to gravity (32.2 ft/sec2)
h = effective head on the orifice, from the center of orifice to the water surface
According to Brater and King (1976) a weir by definition is a hydraulic control structure that is commonly used in detention basin. The structure’s discharge is calculated by the general formula:
Q = Cw L (2gh)3/2
Where
Cw = dimensionless weir discharge coefficient
L = effective weir length, ft
h = water depth above the crest
According to Iowa Stormwater Management Manual a perforated riser is a special kind of orifice flow. The riser used is a vertical pipe punctured with evenly spaced holes. According to McEnroe (1988), the discharge of a perforated riser without orifice plate at the bottom is formulated as:
Q = Cs (2As/3hs) (2gh)3/2
where:
Cs = dimensionless discharge coefficient of the side holes
As = total area of the side holes, ft2
hs = length of the perforated segment of the riser pipe, ft

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