Rainwater Harvesting System as an alternative source of water supply in Burnside Eurocyl LTD in Carlow
Course Code & Name:
Rainwater Harvesting Literature Review
To meet the societal water needs has since been an issue for an extended period of time. There are two main alternatives with regard to fulfilling the sustainable management of freshwater, including finding extra resources of water through traditional unified water sources; and utilizing well the already available scarce water resources more effectively. Water is the most valuable natural resource, and a vast majority of the global population understand the scarcity and the limited supply together with the importance of water particularly in dry continents. The first option has been given wide attention with only limited attention directed towards the second option. This review widely evaluates the way the systems for harvesting rainwater can be employed as an option for supplying water in “Burnside Eurcyl LTD in Carlor.” Further, the literature discusses the impact of rainwater harvesting system on ISO 50001 as well as the components of the rain harvesting, the systems and the efficiency of the technologies used in the harvesting
Freshwater Harvesting definition
Harvesting freshwater is a technique for rainwater collection and storage for a sole purpose of “human use from rooftops, land surfaces or rock catchment” by employing the use of simple techniques, including pots, jars as well as engineering techniques. Accordingly, rainwater harvesting is referred to as the practice of capturing, utilizing or infiltrating water from constructed catchment surfaces, roofs, driveways, sidewalks and parking lotsCITATION Bra08 p 35 l 1033 (Lancaster, 2008, p. 35). Rainwater harvesting is regarded as an effective strategy for conserving water in both urban and rural area of the world; consequently, it is essential in decreasing the unwarranted use of drinking water that is heavily treated for landscaping, toilet flushing together with laundry washing. When rainwater is properly infiltrated, it can also be serve for potable water usesCITATION Who15 p 2 l 1033 (WhollyH2O, 2015, p. 2).
Harvesting rainwater is the process of accumulating, depositing and storing of rainwater for reusing on-site instead of permitting it to get wasted as run-off. Normally, rainwater is harvested from rooftops and then stored or preserved in special tanks. However, with improved technologies, the collected water is usually redirected to wells boreholes, shafts, or reservoirs with percolation. Rainwater harvesting systems are only constructed after assessing the conditions of the site, such as the pattern of rainfall, incident rainfall, and subsurface strata together with storage characteristics. The process of harvesting rainwater is a popular process undertaken across the world; however, it is more common in countries with dry weather countries.
Rainwater is regarded as an “economical, safe and sustainable source of quality water especially when it is captured and stored in an acceptable manner.” The rainwater can be considered safer as compared to the water that is supplied through the mains because the supply via the mains is stored in the dams and are treated by chemicals. The dam water that is then supplied through the mains is known to be pumped through pipes that are bound to be affected with rustCITATION AZo08 p 1 l 1033 (AZoCleantech, 2008, p. 1).
Rainwater Harvesting as an option for supply in “Burnside Eurocyl LTD in Carlor.”
The population in the world is rapidly increasing; this is continually straining the available natural resources like water, soil, and forests. For this reason, there is a need for significant efforts needed to meet the needs of the ever increasing population. Furthermore, the rapid population growth coupled with factors including agricultural intensification, industrialization, urbanization and water-intensive lifestyles is culminating in a water crisis across the worldCITATION Bra08 p 42 l 1033 (Lancaster, 2008, p. 42). “Approximately 20% of the global population lack safe drinking water while about 50% lack access to a safe sanitation system.” Furthermore, the vast falling water tables have caused massive water problems, such as water shortages together with salt intrusion especially in coastal areasCITATION Cha08 p 25 l 1033 (Leidl, 2008, p. 25).
In a similar context, the contamination of the drinking water, as well as the pollution of the water sources, are the main challenges around the globe. The rapidly growing population that is seen today is still depending on the limited supply of the fresh water that is becoming contaminated by day. It is also seen that just like food security, the security of water is also gaining priority not only in the regional sector but across the world as wellCITATION Ash15 p 57 l 1033 (Ashok, Donald, & Ted, 2015, p. 57). Rainwater harvesting has various significant social, economic and environmental benefits. By harvesting rainwater through rainwater collection systems, the over-reliance on water storages dams as well as systems is reduced significantly. It is also found that there is a reduced pressure on the storage systems of water that are then seen to reduce the need to improve the infrastructure of the water storage. More importantly, it considerably reduces the size water billsCITATION AZo08 p 2 l 1033 (AZoCleantech, 2008, p. 2). Specific benefits of rainwater harvesting areas discussed bellow
Easy maintenance: using rainwater harvesting systems is highly beneficial to the community. For instance, the overall cost of installing rainwater systems is lower than costs incurred when purifying and pumping water through the mains. Accordingly, maintenance uses less time and energy. The result is that the water that is collected in used in many ways without being treated or taken through the purification process.CITATION Nan11 p 75 l 1033 (Leveson, 2011, p. 75).
Reduced water bills: rainwater harvesting results into the collection of water that can be utilized in various and several non-drinking functions. Small businesses and families can use rainwater harvesting as a means to reducing their utility bills. Moreover, on an industrial scale, rainwater harvesting provides the required and needed quantities of water for different operations to be undertaken smoothly and efficiently. Additionally, rainwater harvesting reduces the soil erosion burdenCITATION Cha08 p 33 l 1033 (Leidl, 2008, p. 33).
Irrigation: given the fact that little is needed to build new rainwater harvesting system, rooftops are used as workable catchment areas that are directly linked to the harvesting system. There is no need of using generators to pump water. In addition to this, the harvested water is chemical free and thus suitable for irrigationCITATION Nan11 p 78 l 1033 (Leveson, 2011, p. 78).
Decreased demand for ground water: global population is increasing, and so is the demand for water. To meet this increasing water demands, many residential colonies and industries extract water from the ground. Rainwater harvesting ultimately reduces this activitCITATION The12 p 129 l 1033 y (Oweis, Prinz, & Hachum, 2012, p. 129).
Reduced floods and soil erosion: by harvesting water during the rainy season and storing it in tanks and dams, significantly reduces flooding together with soil erosionCITATION Ruc15 p 3 l 1033 (Ruckelshaus, 2015, p. 3).
Components of Rainwater Harvesting
Rainwater harvesting technologies have been present for quite a long period and are essentially used for collection and storage water from rooftops, rock catchments as well as land surfaces by using simple and easy to make techniques including pots, jars, and techniques like underground check dams. Rainwater harvesting techniques are commonly found in Asia as well as Africa that arise from ancient civilization practices presents in these regions. Rainwater harvesting practices serve a major purpose in these regions including a source of drinking water especially in rural areasCITATION Xia11 p 98 l 1033 (Liang, 2011, p. 98). Rainwater harvesting has three major components:
Catchment areas are the areas for collecting rainwater, and they include:
This is the basic rainwater harvesting technology whereby the collected rainwater is stored in simple containers at roof edges. Gutters collect water that drains it to collecting vessels through downpipes specifically designed and developed for this use or deviating water from gutters to tanks for particulate to settle down before water is transported to storage containers for household useCITATION Leo12 p 239 l 1033 (Hopper, 2012, p. 239). In this regard, the main catchment area is the rooftop, and thus, the quantity and quality of collected rainwater wholly rest on the type and area of roofing materials. Galvanized corrugated iron, aluminum, and asbestos cement sheets, slates and tiles are the best surfaces for collecting pure and quality rainwater.
Accordingly, rooftops constructed with gutters made of bamboo and properly laid in slopes have the capacity of producing a similar quantity of runoff at a cheaper cost. Nonetheless, bamboo gutters are not suitable due to health hazards that come with them. Consequently, metallic coated roofs or any other coating are not suitable for this purpose and hence not recommended because of imparting color or tastes to the harvested water. In order to maintain rooftop catchments, they must regularly be cleaned to remove leaves, dust, together with droppings to obtain good quality rainwaterCITATION Leo12 p 240 l 1033 (Hopper, 2012, p. 240).
Land surface catchments
Harvesting rainwater on land or ground catchment is extremely simple and less sophisticated method of rainwater collection. Land surface rainwater collecting includes improving the quantity of the runoff of the surface using different technologies such as drain pipes together with the storage of collected waterCITATION Qia15 p 32 l 1033 (Qiang, John, & Yuanhong, 2015, p. 32). Ground water catchment methods provide an extra opportunity for water collection as compared to rooftop catchments because they provide a wider surface area. It has been seen that the retention of the flow of the small streams into the reservoirs results in lower cost terms. Thus, the technology for harvesting the water is more significant more so when it comes to meeting the demands for supply in the dry seasons.
However, land or ground surface catchments are associated with increased rates of water loss through ground infiltration and due to the marginal quality of collected water. The techniques are best used for collecting water for the firm and agricultural purposesCITATION Qia15 p 33 l 1033 (Qiang, John, & Yuanhong, 2015, p. 33). The available techniques for integrating runoff within land surface catchment areas involve:
Increasing the slope of the land with artificial land cover
Altering or clearing vegetation cover
Decreasing permeability of the soil through compaction and application of chemical CITATION And07 p 152 l 1033 (Pressman, 2007, p. 152)Rock Catchments
Just like the catchment mentioned above areas, rock outcrops are also used as rainwater collecting surfaces. In the event that this catchment area is accessed by children and animals, the rock catchment should be protected in order to collect high-quality water. This is only possible when the surface is well flushed and cleaned prior to any storage takes place. Sloping rocks, for instance, are essential catchment areas, the collecting channels can then drain the collected water into pipes leading to storage tanksCITATION Ale13 p 275 l 1033 (Wilson & Piepkorn, 2013, p. 275)Collection Devices
Harvested rainwater can be stored in storage tanks using guttering that can either be on ground or underground. When using storage tanks to store the harvested rainwater, various precautions must be considered, including the adequate closure of the tank to reduce water contamination from animals, human, or other pollutants within the environment. Accordingly, storage tanks should have tight covers to prevent algal growth together with mosquito breeding. Open tanks are not suitable and thus not recommended for harvesting and storing rainwater for human consumption. The best storage tanks for rainwater collection include motor jars and cylindrical Ferrocement tanks. There is a need to calculate the capacity of the tanks used in storage putting into considerations the whole period of the dry season, the amount of rainfall as well as the rates of water consumption. During the long dry season, there should be large tanks for storing water that can hold a lot of waterCITATION Hea13 p 197 l 1033 (Kinkade-Levario, 2013, p. 197).
Rainfall Water containers
The substitutes for storage tanks that can be used include the battery tanks that are modeled from pottery, the Ferrocement or the polyethylene materials. For example, polyethylene tanks are compactly constructed but have a large capacity for storing large volumes of water. They can be easy to clean and have several openings for fittings for connecting pipes. The commonly used containers in Asia were made of earthen materials and Ferro cement tanks. Rainwater catchment technologies, particularly roof catchments substantially increased during the 1980s and expanded rapidly in different regions of the worldCITATION Mar14 p 105 l 1033 (Robertson, 2014, p. 105).
Systems for water Conveyance
These systems for water conveyance are essential for transferring rainwater harvested from rooftops to storage tanks. The flow of the water into the storage tanks can be enhanced through the connection of pipes linked by gutters on the rooftops. Selection of the system of water conveyance must consider that at the beginning of rainfall, rooftop dirt and debris are washed into downpipe, and thus, the collection of clean water will only be harvested later. Various ways exist through which clean rainwater can selectively collect from the storage tank, including downpipe flapCITATION Stu15 p 142 l 1033 (Echols & Pennypacker, 2015, p. 142).
By using the flap, ensures that the first flush has deviated through the downpipe, and then the later rainwater is conveyed to the storage tank. For instance, at the onset of rainfall, the flap is closed hence directing the collected water to the down-pipe, the flap is later opened when comparatively clean water is then harvested. The drawback of using the conveyance control system is mainly the mandatory obligation of observing the value of the runoff then manually operating the flap. To carefully fill the storage tank, there is a need for ensuring that excess water can overflow while at the same time making sure that pipe blockages or dust in water does not cause any impairment or pollution of the water supplyCITATION Stu15 p 143 l 1033 (Echols & Pennypacker, 2015, p. 143).
Rainwater Harvesting Systems
First Flush Systems
These systems allow for debris, dust, dirt and droppings to be ridden off first; these materials collect on the rooftops as well as from other catchment areas. In this regard, when first rainwater arrives it can be washed into the storage tank. This will ultimately contaminate the water while at the same time reducing the water qualityCITATION Cel14 p 231 l 1033 (Novak, Giesen, & DeBusk, 2014, p. 231). Because of the existing understanding, the systems for harvesting water have developed a subsystem for diverting the first flush water avoiding the contamination of the water in the storage tanks. The flush systems to be used depend on the arrangement operated manually where the inlet pipes are not directed to the inlet of the tank when the rains begin and are replaced immediately the first flush is eliminated. This rainwater harvesting method was a drawback as it demanded the physical presence of an individual to operate the systemCITATION Cel14 p 134 l 1033 (Novak, Giesen, & DeBusk, 2014, p. 134).
Settling tanks and Filtration systems
Various water treatment systems are available. The complexity of these systems also differs from rudimentary to high-end technologies. For example, ingenious filter was developed by WISY a Germany Company, which are fitted into a vertical down-pipe used for both filtration and flush water. For instance, this filter cleverly takes water through a 0.02 mm fine mesh while at the same time a lowing debris and silt to continue down the pipeCITATION hei12 p 164 l 1033 (heib Y. Oweis, 2012, p. 164). Filter efficiency is approximately 90%, and it is used commonly in European rainwater harvesting systems.
Accordingly, “simple trash pack is used in some systems; however, this filtering system has numerous setbacks: it only eliminates bigger debris, the rack is easily clogged and thus requires regular cleaning”CITATION Ind09 p 4 l 1033 (Jeet, 2009, p. 4).
Sand-charcoal-stone filter is mainly used for rainwater filtration prior to its entry into the storage tank. The sand-charcoal-stone filter is only best used when there is a slow inflow or modest and overflows immediately the inflow goes beyond the recommended rate CITATION Ind09 p 5 l 1033 (Jeet, 2009, p. 5).
“Settling tanks and partitions” are extremely important for removing silt as well as solids suspended in the water. They are effective when used; however, using settling tanks and partitions means incurring extra costs particularly when elaborate techniques are used. Many rainwater harvesting systems used to depend on the portion of mosquito mesh that is fine or cloth for filtration.
Sizing of the Rainwater Harvesting System
When planning to develop a harvesting system for rainwater, the storage tank size must be appropriately calculated to give satisfactory storage capacity. In this essence, the needs for storage are determined by various factors that are interrelated, including:
Weather patterns and local rainfall data
The size of the rainwater catchment area
Coefficient of the runoff
Consumption rates and number of users CITATION Oma11 p 65 l 1033 (Mzirai, 2011, p. 65)The techniques used for harvesting rainwater i.e. in the event that the system will be used for partial or total water supply also play a significant role in defining the components of the system as well as their sizes.
When sizing the storage tank, various methods exist. These techniques differ in sophistication and complexity whereby some are undertaken by highly experienced experts, practitioners for the first time while others demand computer-based software together with trained engineers with an extreme understanding of the softwareCITATION Oma11 p 67 l 1033 (Mzirai, 2011, p. 67). In this essence, the techniques used for designing system components are dependent on factors including:
The system’s complexity and size together with its constituents
The tools availability for using a specific system
The level of expertise of practitioners and designersCITATION Oma11 p 68 l 1033 (Mzirai, 2011, p. 68)There are different approaches for sizing rainwater harvesting system components including:
Demand side approach
This is the simplest way of calculating the largest storage requirements with regard to rates of consumption together with occupancy of the building. For example:
“Consumption per capita per day, C = 25 liters
Number of persons per household, n = 5
Longest average dry period = 30 days
The annual consumption = C x n = 125 liters
Storage requirement, T = 125 x 30 = 3,750 liters”CITATION Die13 p 33 l 1033 (Borchardt & Ibisch, 2013, p. 33)The above-described method assumes the availability rainfall that is sufficient, as well as catchment area and thus, can only be best applied in areas with the described condition. Rough approximations of the tank size are acquired through this method.
Supply side approach
Areas with uneven distribution of rainfall, it is required that when designing the storage tank size extended caution should be taken into consideration to size the storage tank properly. In such a case, in the different times of the year, there may be experienced a lot of rainfall as sometimes experience longer dry periods. When the rainfall is enough to satisfy the demands, there will be a need to have sufficient storage to close the gaps. Given the expenses incurred for storage, sizing storage tanks should be carefully designed to eliminate unnecessary expenses. Developing countries are prone to experiencing this scenario where single wet climates are commonCITATION Die13 p 34 l 1033 (Borchardt & Ibisch, 2013, p. 34).
Several computer-based approaches are available for accurately calculating storage tank size. For example the Sim Tanka, the program was developed by Indian organizations and is available on the web free of charge. Sim Tanka; a software program that simulates systems for harvesting rainwater with storage tanks that are covered. This program helps in predicting the system’s performance based on a scientific model of a real and actual system. The Sim Tanka is capable of simulating the fluctuating rainfall that rainwater harvesting system depends on fullyCITATION Bra12 p 59 l 1033 (Chellaney, 2012, p. 59).
This program requires more than “15 years of monthly rainfall records of a place where the rainwater harvesting system will be located.” In the event that rainfall records are not available, then the rainfall records of the nearest place having the same rainfall patterns can be used. Sim Tanka software then calculates the optimal storage capacity or the catchment capacity with regard to user requirements and specifications. Accordingly, the Sim Tanka determines the system’s reliability based on the records of the 15 previous yearsCITATION Bra12 p 60 l 1033 (Chellaney, 2012, p. 60).
Effectiveness of Rainwater Harvesting Technology
The system that is chosen for harvesting the rainwater depends on the rainfall experienced in terms of capacity and intensity. The variables can as well be adjusted to the needs of the household.CITATION TVR15 p 187 l 1033 (Rao, 2015, p. 187). Furthermore, the feasibility of a system for harvesting rainwater is a function of quality and quantity of available water from different available sources; the household’s size and water consumption per capita, and the budget available. Given this understanding, when deciding on establishing a rainwater harvesting system, the decision-maker must balance the project’s total cost against available budget while taking into consideration the economic benefits of water supplied by other sourcesCITATION TVR15 p 188 l 1033 (Rao, 2015, p. 188).
Rainwater Harvesting System and its impact on ISO 50001 in Burnside Eurocyl LTD
By developing a rainwater harvesting system, Burnside Eurocy LTD will be certified in accordance with DIN ISO 50001 for three years. The certification will be valid for three years after which it will be subject to renewal after every one year. Burnside Eurocyl using the rainwater harvesting system will be able to store and infiltrate the harvested water.
Harvesting rainwater has been in existence for a prolonged period. This literature review has explored various literature regarding rainwater harvesting system and how it can be an alternative source of water supply in Burnside Eurocyl LTD in Carlor. For instance, the literature has discussed the benefits of rainwater harvesting as well as its components. According to this exploration, there are three main components of rainwater harvesting; catchments areas (rooftops, land and ground surfaces, and rock catchment areas), storage tanks, and rainwater conveyance systems. There are several rainwater harvesting systems, including the first flush systems and filtration systems and storage tank. Various techniques are also employed when sizing tanks for rainwater storage, including the demand side approach, supply side approach, and computer-based approach.
BIBLIOGRAPHY Ashok, S., Donald, B., & Ted, G. Rainwater Tank Systems for Urban Water Supply: Design, Yield, Energy, Health Risks, Economics and Social Perceptions. . (2015) New York: IWA Publishing.
AZoCleantech. What is Rainwater Harvesting and the Importance of Harvesting Rainwater. (2008). Retrieved December 18, 2015, from http://www.azocleantech.com/article.aspx?ArticleID=65
Borchardt, D., & Ibisch, . Integrated Water Resources Management in a Changing World: Lessons Learnt … (2013). New York: IWA Publishing.
Chellaney, B. Water: Asia’s New Battleground. (2012). New Delhi: HarperCollins Publishers.
Echols, S., & Pennypacker, . Artful Rainwater Design: Creative Ways to Manage Stormwater. (2015). New Delhi: Island Press.
Heib Y. Oweis, . P. Rainwater Harvesting for Agriculture in the Dry Areas. (2012). Australia: CRC Press. Copyright.
Hopper, L. J. Landscape Architectural Graphic Standards. (2012). Berlin: John Wiley & Sons.
Jeet, I. Rainwater Harvesting. (2009). Chicago: Mittal Publications.
Kinkade-Levario, H. Design for Water: Rainwater Harvesting, Stormwater Catchment, and Alternate … (2013). Chicago: New Society Publishers.
Lancaster, B. Rainwater Harvesting for Drylands and Beyond: Water-harvesting earthworks. (2008). New York: Rainsource Press.
Leidl, C. M. Building Capacity for Rainwater Harvesting in Ontario: Policy and Economic Considerations. (2008). Guelph: University of Guelph,
Leveson, N. Engineering a Safer World: Systems Thinking Applied to Safety. (2011). London: MIT Press.
Liang, X. The Economics of Sustainable Urban Water Management: the Case of Beijing … Melbourne: (2011). CRC Press.
Mzirai, O Modeling of MacRo-Catchment Rainwater Harvesting in Semi-Arid Areas. . (2011). Lambert Academic Publishing: New York.
Novak, C. A., Giesen, . V., & DeBusk, . M. Designing Rainwater Harvesting Systems: Integrating Rainwater Into Building Systems. . (2014). Hong Kong: John Wiley & Sons.
Oweis, T. Y., Prinz, ., & Hachum, . Y. Rainwater Harvesting for Agriculture in the Dry Areas. Toronto: (2012). CRC Press.
Pressman, A. Architectural Graphic Standards. . (2007). New York: John Willey & Sons.
Qiang, Z., John, G., & Yuanhong, L. Rainwater Harvesting for Agriculture and Water Supply. Washington DC: Springer. (2015).
Rao, T. Effective People:. India: Random House. (2015).
Robertson, M. Sustainability Principles, and Practice. (2014). London: Routledge.
Ruckelshaus, W. What is Rainwater Harvesting? (2015).Retrieved December 18, 2015, from What is Rainwater Harvesting?
Sharma, A. K., Begbie, ., & Gardner, Rainwater Tank Systems for Urban Water Supply: Design, Yield, Energy, Health … . (2015). Mexico City: IWA Publishing.
WhollyH2O.. Rainwater Harvesting (RWH) Defined. (2015). Retrieved December 17, 2015, from http://www.whollyh2o.org/rainwater-stormwater/item/48-rainwater-harvesting-defined.html
Wilson, A., & Piepkorn, Green Building Products: The GreenSpec¨ Guide to Residential Building … . (2013). New York: New Society Publishers.
Zhu, Q., Gould, ., & Li, . Rainwater Harvesting for Agriculture and Water Supply. Manchester: Springer. (2015).