Hydraulic Services Systems: Third Pipe System - Assignment Example

Student Name: Tutor: Title: Third Pipe System. Date: ©2016 Table of Contents 1.Introduction 3 1.1Definition 3 1.2Quality and type of water sources 3 2.Case Study: - Existing Third Pipe System 4 2.1Overview 4 2.2Viability of Retrofitting Existing Buildings Using Third Pipe System In The Future 6 2.2.1Cost-effectiveness Analysis: 6 2.2.2Safety and Public Acceptance Analysis: 7 2.2.3Economic Impact Assessments: 7 2.2.4Desire End Use: 7 3.Conclusion 8 References 9 1. Introduction 1.1 Definition A third pipe system is a system of pipes used to deliver alternative water [Wat13]. The main purpose of this water is usually to reduce water demand for an area. The water however is not suitable for drinking and is therefore supplied using well labelled pipes to prevent this confusion. It is usually used for irrigation of lawns and gardens, flushing of toilets, washing of vehicles and laundry purposes. Figure 1: Third pipe system water applications The sources of this water may either be from treated wastewater, sewer mining, superficial groundwater and storm water. It is not usually advisable also to use this water to irrigate fruit trees or even vegetables due to the pathogens it may contain. 1.2 Quality and type of water sources Recycled water may come from different sources that may include effluent, storm water and also seawater. Effluent may be recycled from either a wastewater treatment plant or a sewage plant. The water quality of such water mainly depends on the purpose for which the water is supposed to fulfil. Such water is in most cases used for irrigation schemes both in the rural and urban areas, industries, residential non drinking purposes, drinking and recharge to the environment. Water may also be recycled from the greywater. Greywater basically represents water from the showers, laundry and kitchen. The quality of this water is usually low and the water is mainly used for household gardens. Another source of this water is from the storm water whereby water from the runoff is recycled. The water quality in this case is good and may also be used for drinking. Basically, this water is in most cases used for recharging the underground reservoir. Finally, desalinization of sea water is another method of recycling. This process mainly involves reverse osmosis and is usually an independent process and helps increase the water sources of the area. This process however is usually very expensive and uses very complicated technologies. Figure 2: The desalinization process for transmission in the third pipe system 2. Case Study: - Existing Third Pipe System 2.1 Overview Owing to the increased demand for water as well as the need to supplement this dwindling resource, governments as well as other stakeholders have come up with a way of conserving this resource through methods of supplementing it and managing it. The connection of recycled water in many homes has become very popular with the homes using this water to flush toilets and also irrigate their lawns. These pipes in most regions of Australia are purple in colour and are mostly accompanied by a sign that prohibits people from drinking the water since in most cases it is not potable. There are a number of third pipe systems in Australia mainly in Melbourne area. The pipe systems in this matter is usually constructed based on the need for recycled water. The area has a high demand for water due to the need for irrigation and watering purposes as well as flushing the toilets. One of these cases is of a 60L buildings in Carlton Melbourne. The buildings are located in the business district of the area and includes technologies for rainwater harvesting for reuse and also greywater and blackwater recycling [Far09]. The buildings being built came about as a desire for the Australian Conservation Authority to design and construct buildings that are commercially viable. These buildings mainly aim at material sourcing efficiency that aimed at reducing material requirement by reusing the existing materials by use of environmentally friendly materials. This also helped them reduce the costs of building. The third pipe system therefore came about in order to fulfil this desire of protecting the environment and also reduce the cost of the utility as well as supplement the water needed by the community. In that case, rainwater collection and use is highly encouraged also with rain water being the principal source throughout the building. The system is designed to replace the water in the mains water control. The main system of recycling is from the rainwater but also the grey and blackwater is also treated [Far09].In the greywater and blackwater recycling system, the water is directed to a tank as combined effluent. It is then treated in a sewage treatment plant using the biological process that allows natural processes to convert the organic material in the effluent. The rainwater is used directly for the purposes of irrigation. As opposed to the treated water, the rain water can be used for both vegetables and fruit trees. This water is then taken to the houses using another pipe usually in most cases purple in colour. The water can then be used to flush toilets or water the lawn. Another area that uses the system is Aurora Estate Development. It is a large scale residential area approximately 20km north of Melbourne in Epping North and it provides 8500 dwellings [Far09]. The development of a third pipe system in the area was necessitated by the need for demand management, wastewater treatment and reuse and storm water quality retention and treatment. Demand management basically means that the area experiences a very high demand for water and hence alternative means of water supply and source had to be sort and also the area needed its little amount of water well managed to avoid misusing this utility. The recycling process was the best alternative since it is cost friendly and also helps protect the environment in the process too. This process would also lead to good management of the water since all the water used would not go to waste but would rather find its way back to the households and be used for other purposes. Wastewater treatment and reuse involves directing the water that is meant to go to the sewer line for instance and letting it undergo a process of removing the pathogens and then it is used again in the homes. Reuse involves the use of that water the way it is for instance using the water from washing clothes to flush the toilets. Storm water on the other hand is used to recharge the groundwater. Its quality is good and hence it does not have to undergo any treatment. In order to do this, a wastewater treatment plant was built in a part of the land separate from the development. Two plants that include the Aurora Sewage treatment plant and the Aurora Water Reclamation Plant were constructed in order to produce different qualities of water to maximize the opportunity for all the wastewater to be reused. The water is supplied to the community for toilet flushing and outdoor irrigation while the excess is delivered to other off-site users. The quality of this water is quite good since it undergoes a three barrier removal process and then the water is chlorinated [Far09]. The water is then supplied using purple pipes and taps and is well labelled to warn people about drinking this water. 2.2 Viability of Retrofitting Existing Buildings Using Third Pipe System In The Future Due to the increased demand for water, there is need to employ methods of conservation of this resource to avoid its depletion. One of these method is through the reuse and recycle process. In order to determine the viability of this system in the future, we should look at the impact and also the need of this system. In order to do this, we need to assess the economic viability of a recycled water scheme using the marginal value of the scheme and a cost benefit analysis [Phi13]. There are also other methods apart from the Cost Benefit Analysis that can be used to assess viability. 2.2.1 Cost-effectiveness Analysis: In this case, we should look at the output of a project but not in monetary terms. It compares the costs of different project options with the same output. Third Pipe System do not take into account the effects on other enterprises or individuals and it also does not consider opportunity cost. For that matter, it should be used together with other methods. Furthermore, minimizing the risks of cross connections would involve high costs as there would be need for close monitoring and compliance checks. Maintenance costs for this system are therefore quite high. Despite the fact that it is comparatively easy to install third pipe systems in Greenfield Developments, the cost of retrofitting them into existing urban areas is prohibitive. However fitting them on low cost establishments is quite easy and cost effective.[Won09]. Figure 3: A cost effective retrofitting onto existing infrastructure 2.2.2 Safety and Public Acceptance Analysis: This analysis deals with the impacts on individual community groups. Most members of the public do not take the idea of third pipe systems delivering second grade water to their residence for different uses with welcoming hearts. The risk of cross connection seems unavoidable to most people, this can subsequently lead to non-potable water reaching the kitchen tap. A good example of what could happen in such a case is what happened in Netherlands where public health and confidence in water institutions was gravely affected. Risk minimization would also be high as mentioned in the previous section. 2.2.3 Economic Impact Assessments: This looks mainly at what benefits the community might expect to flow from the taxpayer. The potential impact on total water demand will be relatively minor and will only become significant over a long period of time. Climate change and drought can have a much more rapid impact on water supply. The decision makers therefore ought to reassess information about the distribution of benefits and costs. Using this therefore, it is possible to identify where the third pipe system fits in best [Wat13]. Measures should therefore be taken to reconsider the installation of third pipe systems. 2.2.4 Desire End Use: Another way of analysing is using the use value benefits. This is the benefit that is gained by the customer if they are supplied with the recycled water and is such benefits that will motivate them to installing the third pipe systems in their houses. In this case, one has to look if the potable water and recycled water are substitutes and if they are not, one goes ahead to check the benefits brought about by the use of each water. This may mean that a person can decide to have recycled water connected to them for agricultural purposes since they have a higher value of nutrients [Sch11]. 3. Conclusion On the basis of acceptance by the public, sometimes people are resistant to use the water since they associate it with the place of origin and are dissatisfied with the treatment process it has undergone. However, due to the increased demand for water, recycled water is gaining more popularity. This was evident when Brisbane experienced a serious drought that prompted the local government to use reclaimed water to supplement their water supply and the public readily accepted it since they did not have any alternative [Bla16] Water safety is also an area of concern when assessing the viability of the future of a third pipe system. The water can be produced in different qualities depending on the stages of treatment it has undergone making it either potable or non-potable. In cases where the water is potable, it can be used to supplement other water sources comfortably. The non-potable one can also be used for other purposes such as irrigation hence saving the amount of potable water used in the farms or lawns. Finally, there is need to assess the end use of the water so that it can be possible to decide the acceptability of the recycled water. In most cases, the water is usually used for flushing the toilets hence the third pipe system would be highly acceptable since all homesteads have toilets that need to be flushed. References Wat13: , (Corporation, 2013), Far09: , (Caitlin, 2009), Phi13: , (Pickering, November 2013), Won09: , (Wong, 2009), Sch11: , (Schuster, et al., 2011), Bla16: , (Anon., 2016), Read More