Ensuring Availability of Water in East Santa - Term Paper Example

TEAM PROJECT REPORT Abstract This proposal is about water portability and availability in East Santa. First there is a background on water problem in the study area. There are three design options which have been addressed: Design A, Design B and Design C. In design A water was to be supplied strictly from the river , design B would involve only water harvesting while design C would be a combination of A and B. From analysis design C was found to be the best option. Table of contents Abstract 2 1.0 Introduction 4 1.1 Background 4 1.2 Objective of the project 7 1.3 Project Scope 7 1.4 Limitation of the project 7 2.0 Problem analysis 7 2.1 Major issues 7 2.2 Design criteria 8 3.0Design Choices 9 3.1 Design A 9 3.2 Design B 9 3.3 Design C 10 3.4 Analysis of Design Options 10 4.0 Conceptual Design 12 4.1 Sand filter 12 4.2 Pipe sizing 13 4.3 Distribution Systems 15 5.0 Benefits 15 5.1 Environmental 15 5.2 Economic 16 5.3 Social 16 5.4 Use of local materials 16 6.0 Conclusion 16 7.0 Reflection 17 References 18 1.0 Introduction 1.1 Background Ensuring availability of water in East Santa is found to be highly seasonal and this is something that needs to be addressed. During the dry season, that takes about three or four month, there is high water scarcity calling for tight management and sparing use of the commodity. It is during this time that most community members use the sea for all their sanitary needs including bathing and clothe washing as a precaution of saving the small supply of clean water that is to be used for cooking and drinking. The major supply source of water in East is rain water, springs, wells and/or rivers. At East Santa accessibility to water is influenced by the season of the year, the vicinity of a river or a spring to the community members and the economic ability of the people. During the rain season rainwater is available at is accessible through rainwater tanks that are shared either at household or/and community level with the facility being located at points easily accessible such as churches, education facilities or at Nakamals (traditional meeting points). The plastic tanks are in common use and they are available at Luganville, even though most of the residents find the tanks to be unaffordable. Guttering is set up on to facilitate collection of water from catchments which are majorly roofs of building made of corrugated iron sheets. In some cases more so where corrugated roofs are not present there is improvisation where a large sheet is placed on a tank so as to act as a catchment to collect rainwater that is then directed to the tank. From the information received from the community representatives, some of the residents who have with houses with traditional thatched roofs do not harvest rainwater from these houses. This is seen to be a great challenge owing to the fact that these residents are lacking the desired roof type because of their financial situation and yet they will need both the right roofing in addition to the tanks before they are able to access the rainwater. Apart from the water tanks wells are another alternative that is found to be in common use. The wells just as the tanks are used for collecting rainwater and their design is such that they are partially underground and water is directed in from the corrugated sheet catchments. Well construction is usually a community venture with local materials put into use including cement, blocks, corals, local stones and occasionally iron rods are also put into use. The wells may be provided with covers sometimes but in most cases the well will be open. The wells just as the water tanks only serve for collection and storage of rainwater and no water abstracted from underground is directed to them. Use of water from wells and tanks is a preference of most households but this water is not in adequate quantities that can be used all year long. Springs and rivers also provide water to the residents on a communal basis. A good case being that of river Natawa that is permanent and is a source of water to Natawa community in addition to being relied on for water supply by other communities during the dry season when the rainwater from tanks and wells in no longer available. In the dry season access to water means residents have to walk fetch water from the river with buckets or water is ferried by a truck which carries large number containers where the community leaders take care of the organization process. With the trucks for fetching water being scarce, on average it takes residents 2 hours everyday to fetch water during the dry season. The alternative of using water from the spring has its challenges, with the springs being located at sea level it means that access this water involve moving up and down steep slope on a thin dirty path. This project aims at increasing water capacity East Santa. Apart from accessing water it is important that the water is of desired quality. As a way of addressing water quality some communities and households in East Santa have systems that ensure that drinking is separate from that used for general purpose in some cases the water being boiled. In a typical example of this practice, one of the community leaders was reported to be having two storage systems , one being a tank which is covered and providing water for drinking and the other being an open tank from which general use water is obtained. Even with this attempt of having quality water , information that obtained from some community representatives indicated precautions such as boiling water was not a common practice and majority could not afford or were not keen having a separate system from drinking water. Rainwater tank was reported to be the preferred water source in comparison to any other source of water as it was seen to be cleanest and safe for drinking. Water from the river was pointed as being dirty and was only used as a last resort when rainwater tanks had dried up. The other source of water that was mentioned was spring water. The issue of the problem associated with the spring water was that some of the spring sources had salty water with at least two out of three primary points reported having this problem. 1.2 Objective of the project Having seen the challenges faced by the people of East Santa this project aims at increasing water capacity East Santa. 1.3 Project Scope In order to have a water system that is adequate it will require that the limitation of the current system to explore the alternatives that can improve the situation. The design will look into the design option available and their approximate costing. 1.4 Limitation of the project While water supply has many problems including wastage at house hold level and contamination of the water sources, this project will be restricted to design looking at design in terms of water pump and roof catchment area and water tank size. 2.0 Problem analysis 2.1 Major issues We need to put in place a water system that is able to make maximum use of the water resources available in the project area. In coming up with a design it is important to put into consideration the available resources in the area and the cost implication that will come with the system. With rainwater harvesting already in place and it currently being seen as the source of cleanest water, it is important that deviation from this water source be justified and the possibility or challenge that it be the sole source of water be analyzed. In order to have adequate water available in East Santa will mean to have some communal reservoir and some distribution network not ruling out installation of a pump. 2.2 Design criteria In this project the aim is to increase capacity of portable water available and to ensure that the water is available through the year. From the background we have seen that spring water is mostly salty a reason that rules it out from being considered for preliminary design. There can be a possibility of increasing the rainwater capacity so as the demand for the entire year is satisfied from this water source. This will involve calculating the area of available catchment area and designing storage facilities that will put into consideration both the demand and the catchment. Another option is having full reliance on water from the river. This will involve establishing the water demand and projecting the future demand. The design need to incorporate water purification bearing in mind that that river water need to be purified to meet the desired standards. The water is then supposed to be pumped to a reservoir point through the rising main and from the reservoir there is to be distribution. The pump that is to be used for pumping need to be properly sized putting into consideration the design=red discharge and the elevation of the reservoir. The pipes size and materials for connecting pipes are also to be established. Installation of a multi-stage centrifugal pump that will draw water at abstraction point and push it to the reservoir (Schueler, T., D. et al. 2007). Water distribution pipes are not be exposed at the surface of the ground as a measure against vandalism. 3.0Design Choices 3.1 Design A In this design we consider using the permanent river Natawa to supply water to the resident as the only means of water source. This means that water will be abstracted from the river then pumped to a storage point where it will be distributed to residents. This project will involve installing diesel powered pump that is able to pump enough water serve the people East Sante. 3.2 Design B From the background it has been said that the dry season last for 3 to 4month a year. From this information it can be easily be concluded that with appropriate design it is possible to harvest rainwater that is able to serve residents throughout the year. For this to happen there will be need to utilize the roofs available fully and to increase the tank capacity at household level or at community centres. This design option will involve minimal pipe work use. No installation of a pump will also be involved. 3.3 Design C In this option we consider using both the river water and the available water harvesting structures. This design involves putting to maximum use the rain water which is available most of the time of the year. This will involve water being pumped from the abstraction point to a reservoir where it will be distributed to consumption points. This was will be directed to the tanks which are used in water harvesting bearing in mind that at the point of utilization of this water rainwater will not be available. There will also be some water points for public use for those who do not have tanks and wells because of lacking corrugated roofs. 3.4 Analysis of Design Options In order to be able to analyze the three options we need to assess them in terms of cost factor, reliability factor, environmental sustainability, ease of operation . in the first design we see that there is reliance only on rainwater. The water is managed at very small units since the current organization of water harvesting is retained only that there will be expansion of the water harvesting capacity. As much as there is rainwater most of the time in the year, this design mey be seen as being unreliable. This is because even with increased capacity with improper management of water or damage of tanks there is likely to be no guarantee of water especially at the dry season. In terms of cost it will require increase the roof collection by having more gutters. The tanks need to be increased considerably for them to have capacity to store water to last the entire dry season. With increased tanks and water expected to last for up to four months in the tanks it means increased repair cost and need to have some form of treatment of the water to ensure safety for use. Option B we see that water harvesting will not be considered. This is what happens in most urban areas around the world where water is sourced from a central place and rainwater is not harnessed from the available structures. In terms of reliability, the system may be considered to be more reliable than design A if not the same. This is because for this system water supply management is at a central place and this means that availability of water during is majorly determined at the central point. But there is a possibility of machine break down where the entire community will lack water. In terms of environmental sustainability the system may lead to over extraction of water in the river. This design substantial initial cost for filtration system construction of reservoir and the piping. And also there will be need to have management cost and also fuel cost throughout the year. Design C is a blend of A and B. In this design no much cost will be directed toward expansion of water harvesting at household or community level. The current structures are expected to be supplemented with water from the river with similar structures as those proposed in B being put in place. Operation cost will be lower because in the rain season the water requirement from the river will not be high. The reliability will be however be high because with both system in place one will almost be guaranteed of water throughout the year. Bearing these factors we can come up with a matrix that will help choosing the suitable design. Table 1 Assessed quality Weighting Design A Design B Design C Cost 0.4 0.1 0.4 0.6 Quality of water 0.4 0.7 0.7 0.6 Environmental sustainability 0.1 0.6 0.3 0.7 Ease of operation 0.1 0.4 0.3 0.6 Total weighted score 1.0 0.42 0.5 0.61 From the table it can be seen that the best alternative is Design C. It can also be seen that design A has the least weighted score. 4.0 Conceptual Design 4.1 Sand filter Water from the river may sometimes have turbidity problem. Also river water may be contaminated by pathogens which maybe harmful to human health. In this design the possibility of direction water to the sand filter by gravity will be explored. This water system will therefore include a sand filter system with filtering ability of up to per hour. The filter as can be seen from the figure has three concentric section with the out, central and inner chambers being filled with sand, course aggregate and pebbles respectively. There is collection of water at the sump which is located underneath the filter where it is then pumped to the reservoir (Dwivedi, 2009). . Figure 1 4.2 Pipe sizing The sump will be located at a lower region compared to the reservoir tank that will also be located at a raised ground in relation to water outlet points. This means that in order to raise the water to the desired height the pump will have to raise the water to appropriate pressure. The pump to be used need to of appropriate size and capable of providing the desired strength that will match the pressure in water otherwise it will burst under the water pressure (BIS-1742-1983,1983). In order to calculate the required dimension of the pipe Barlows formula is used Where the Where p = 2St/D With, p is water pressure, S is the material strength for the pipe (material strength), t gives the thickness of pipe while is the pipe diameter In this design we settle for PVC pipe that has a material strength of 160psi (1111.612kpa). The water is to overcome a head of about 30m including the friction losses and elevation of the tank. The pipe diameter is to be chosen to ensure water is passed through the pipe at allowable speed limit with velocities of over 3m/s being discouraged at such velocity there is high friction losses. Choosing a velocity of 1.8m/s and putting the discharge from the sump at discharge at 6kg/s which translates to 0.006m3/s. Cross section area of pipe  Area A= =3.86” Now applying Barlow’s formula and with relevant substitution p = 2St/D t = 0.014m=0.56” 4.3 Distribution Systems With water pumped from the sump to a reservoir located at an elevated point the water will use elevation pressure with appropriate sized distribution pipes to avail water at the utilization points. The distribution pipes need to be appropriately sized so as to ensure that deliver water at appropriate discharge rate and velocity through pipe is also in the desired range. 5.0 Benefits 5.1 Environmental With regard to environment supply of water supply will be of benefit to the community. When water is not available during the dry season people will converge at one point to draw water at spring or along the river. This converging at a single water point is always exposes environment degradation. With water supplied throughout the year this will not be the case meaning that the environment will be protected. Also with the burden of fetching water removed people will have more time to involve in beneficial activities such as putting there land into good use which results to improvement of the environment. Also when there is short supply of water we have seen that people resort to bathing and directly at the sea. This practice is harmful to the environment due to the chemicals that are disposed in the water. With water supplied at homes throughout this problem will be addressed. 5.2 Economic With portable water provided to the community there will be improved sanitation which will impact on the health of the people. A health person will be more productive. the burden of fetching water that is removed means that there will be time for engaging in other economic activities. With water supply taken care of there is conducive environment of establishing small industries such as poultry and pig slight houses. 5.3 Social The free time that comes from water being easily accessible means that people can have free time and energy engage in social activities. The availability of water means that we can have the water that can be used at social amenities such as local stadiums where the water can be used for watering the play grounds and ensure there are conducive for use through the year. The free time save from fetch water may also be used to take care of the social amenities which in itself will increase socialization even before taking part in the sporting activities themselves. 5.4 Use of local materials In this project there will be utilization of materials. In the sump and reservoir construction local materials such as blocks, cement will be used. Blocks will be made using local people and local artisan will be involved in construction. The pipes will be sourced from the local market. 6.0 Conclusion This proposal has looked at various issues that concern water supply systems. First the water problem facing the East Santa was defined. The water available resources were highlighted. The proposal discussed briefly the various options that can be used to ensure there is water of right quality to the community members. The best option was found to have a design that incorporates water harvesting and water supply from the river. 7.0 Reflection Coming up with a design is highly beneficial for the participants. Being involved in the water project for East Santa community is seen as a big opportunity to put to use what has been learnt in class and also what will be learnt in later years of study. The process of coming up with a proposal was helpful in having close interaction with fellow students and the lecturer. It helped in developing presentation skills and time management. References BIS-1742-1983 (1983). Sizing of RW Pipes for Roof Drainage Bureau of Indian Standards, New Delhi. Dwivedi A. K. (2009). Domestic rooftop water harvesting- a case study. ARPN Journal of Engineering and Applied Sciences LRHF.(2001). A Report Domestic Roof Water Harvesting and Water Security in the Humid Tropics prepared by Lanka Rainwater Harvesting Forum under Domestic Roof Water Harvesting in the Humid Tropic. Forasté, J. Alex and Hirschman David. 2010. A Methodology for using Rainwater Harvesting as a Stormwater Management BMP. ASCE International Low Impact Development Conference, Redefining Water in the City. S T. Younos. an Francisco, CA. Read More

The wells just as the tanks are used for collecting rainwater and their design is such that they are partially underground and water is directed in from the corrugated sheet catchments. Well construction is usually a community venture with local materials put into use including cement, blocks, corals, local stones and occasionally iron rods are also put into use. The wells may be provided with covers sometimes but in most cases the well will be open. The wells just as the water tanks only serve for collection and storage of rainwater and no water abstracted from underground is directed to them.

Use of water from wells and tanks is a preference of most households but this water is not in adequate quantities that can be used all year long. Springs and rivers also provide water to the residents on a communal basis. A good case being that of river Natawa that is permanent and is a source of water to Natawa community in addition to being relied on for water supply by other communities during the dry season when the rainwater from tanks and wells in no longer available. In the dry season access to water means residents have to walk fetch water from the river with buckets or water is ferried by a truck which carries large number containers where the community leaders take care of the organization process.

With the trucks for fetching water being scarce, on average it takes residents 2 hours everyday to fetch water during the dry season. The alternative of using water from the spring has its challenges, with the springs being located at sea level it means that access this water involve moving up and down steep slope on a thin dirty path. This project aims at increasing water capacity East Santa. Apart from accessing water it is important that the water is of desired quality. As a way of addressing water quality some communities and households in East Santa have systems that ensure that drinking is separate from that used for general purpose in some cases the water being boiled.

In a typical example of this practice, one of the community leaders was reported to be having two storage systems , one being a tank which is covered and providing water for drinking and the other being an open tank from which general use water is obtained. Even with this attempt of having quality water , information that obtained from some community representatives indicated precautions such as boiling water was not a common practice and majority could not afford or were not keen having a separate system from drinking water.

Rainwater tank was reported to be the preferred water source in comparison to any other source of water as it was seen to be cleanest and safe for drinking. Water from the river was pointed as being dirty and was only used as a last resort when rainwater tanks had dried up. The other source of water that was mentioned was spring water. The issue of the problem associated with the spring water was that some of the spring sources had salty water with at least two out of three primary points reported having this problem. 1.2 Objective of the project Having seen the challenges faced by the people of East Santa this project aims at increasing water capacity East Santa. 1.3 Project Scope In order to have a water system that is adequate it will require that the limitation of the current system to explore the alternatives that can improve the situation.

The design will look into the design option available and their approximate costing. 1.4 Limitation of the project While water supply has many problems including wastage at house hold level and contamination of the water sources, this project will be restricted to design looking at design in terms of water pump and roof catchment area and water tank size. 2.0 Problem analysis 2.1 Major issues We need to put in place a water system that is able to make maximum use of the water resources available in the project area.

In coming up with a design it is important to put into consideration the available resources in the area and the cost implication that will come with the system.

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