Irrigation and Efficient Water Distribution - Research Paper Example

First Sur Research Essay 24 March Irrigation And Efficient Water Distribution Through Conservation And Rain Harvesting Introduction: Irrigation, simply defined, is the application of water to land for agricultural and related land use. In addition to being the world's largest user of water (Ward and Pulido-Velazquez), it imposes arguably the greatest level of necessity on water-deficient areas, globally. Generally, irrigation seeks to achieve a primary objective of well-drained, healthy and productive land, to enhance or sustain viable agriculture. However, with the general awareness that the resources of clean (usable) water are becoming scarcer (Noah) and new water sources growing increasingly expensive (Morris), the application of methods which conserve water (while achieving the above-stated objective) becomes naturally relevant, in the irrigation equation. Water Conservation- Importance and Primary Objectives: Water conservation is a general reference to methods or procedures applied for the purpose of achieving a reduction in water usage or consumption. Around the world, there are a wide variety of methods associated with water conservation, for an equally wide variety of purposes. Regardless of diversity in technique, there is a primary objective common to all the methods- the use of less water while achieving irrigation's necessary end. Needless to say, the interplay between the reduction in water consumption and achievement of viable irrigation introduces the question of water use efficiency. In irrigation, water reuse and recycling become crucial considering the heavy use of the resource (water), and indeed its wastage. The FAO Corporate Document Repository states in a report that "40% or more of the water diverted for irrigation is wasted at the farm level through either deep percolation or surface runoff." Moreover, "water conservation has been found to be a cost-effective way to meet increased water demands. Conserving water by consuming less, wasting less or reusing more reduces cost and postpones or eliminates the need for expensive and environmentally damaging new dams or similar water supply projects." (Texas Water Matters). For centuries, water reuse and recycle have been an integral part of the techniques applied to the irrigation of land, for effective ecosystem management (Noah). Without doubt, it is not totally devoid of drawbacks, in an environmental context. However, as a result of its relatively natural mode of application, it has (and is) successfully been used in many places around the world to achieve environment-friendly irrigation. Rain Harvesting and Water Conservation- Usefulness And Applicability in Irrigation: The interconnected nature of the entire ecosystem and the hydrological cycle ensures that ensures that irrigation does not function in isolation. For this crucial reason, water conservation as applied to irrigation, assumes greater relevance regarding the availability of water for other uses. A vital approach is that the end-use of water needs to feature more prominently in the methodology considerations of irrigating land. For instance, gray water usage- an aspect of water conservation- basic as it may be, surprisingly encapsulates the is water-efficiency philosophy. One of water conservation's crudest forms, gray water use is generally believed to be unsuitable for irrigating certain types of ground or plants- on account of its high acidic or chemical content- and in certain places (such as California) is restricted by legislation as applicable only to non-edible plants (Alyce). However, the author notes, it finds reasonable applicability, being useful in the "subsurface irrigation of non-edible plants." Conservation, in such a case, has successfully helped avoid a situation of wastage or inefficiency through a proper recognition of end use, even in this most basic or crude mode of irrigation. Other aspects of water conservation also appear to be naturally inclined to efficiency, particularly with the end use of water properly defined. Artificial Recharge, notes Payne and Neuman, is applicable in "urban or rural settings where runoff does not readily seep into the ground it can be simple and low-tech to to technical and complex- depending onthe end use of the water" Rainwater harvested from rooftops in locations of heavy air pollution is one of the environmental negatives associated with this aspect of water conservation in irrigation. Hazards from such cases, would be more or less the exception. Rooftop rainwater harvesting has been known to generally yield rainwater of a quality "superior to well or tap water, usually softer and with fewer dissolved solids." (Payne and Neuman). Rooftop harvesting systems vary in cost and complexity depending on the quantity and quality of water requirements. The profound usefulness of rainwater harvesting in irrigation is probably underscored by the fact that even wet areas- which apparently have no cause to worry about water- still find it useful. Hence, rain barrels are used in places such as Tacoma, for instance, for rain-watering gardens and lawns. This deceptively simple technique is known to be capable of capturing 10,000 gallons of water yearly (Payne and Neuman). The micro-attachment method of rainwater harvesting- again a relatively natural water conservation method- has proved useful over the years, particularly in the world's rural areas. Rainfall is directly received into dug-out sections of ground bounded by earthen walls or 'check dams', in a process that efficiently utilises water made available by heavy rainfall. Noah notes that it is a technique "that takes advantage of rainwater that evaporates too quickly to seep into the water table,or that would carry surface pollutants to streams and lakes". The benefits of this conservation method have been experienced in the Alwar district of India, where in 1985 it was applied in de-silting and deepening a check dam along the Arvari River- which had more or less been reduced to a pond. This application caused the pond to fill to a point where it recharged the acquifer and refilled the wells; within the Alwar district, over 7500 such structures have been constructed to capture rainwater. The wells are now full, and have sustained villages along the basin even through periods of prolonged drought. This has impacted the ecosystem generally, as rivers (within the basin) that had hitherto stopped flowing, are now rejuvenated (Payne and Neuman). Irrigation, in its mechanised, heavy-technology mode, has the drawback of bringing up dams on rivers, thereby straining the capacity of surface waters. Irrigation projects also "draw on aquifers while water tables decline"(Payne and Neuman). The authors also note that today's mechanisms for controlling water may, afterall, be inadequate to augment the freshwater cycle in a manner capable of sustaining water availability. The demands of 'modern' irrigation have invariably entailed re-designing of the landscape for water diversion and control, as well as the creation of tunnels of dams. However, in Denver, water conservation- through water pricing- has been found to be capable of substituting for a proposed dam costing over $500 million (Morris). In irrigation terms, this translates to water conservation having the potential to be equivalent to a dam- without the attendant environmental costs of the dam. The water department in Denver estimates that, by metering water users- so that there is a financial incentive to save water- customers will use 20% (representing 10,000 acre feet) less less water per year than they did before metering (Morris). Later estimates- according to the same author- even suggest savings of around 25%. Water Consumption And Its Crucial Role In Efficient Water Distribution: Reductions of indoor and outdoor use of water is particularly instructive, for attainment of water-efficient irrigation. This, particularly in areas with relatively high levels of water availability, which (perhaps unwittingly) tend to take the resource for granted. Water users in Ohio (an area that generally receives a high level of rainfall), for instance, "daily withdraw 11 billion gallons of water from streams, lakes and acquifers, 1.6 billion of this consumed by rural and public water systems." (Water Use in Ohio). Furthermore, "Ohioans use 50 gallons of water per person daily", notes this source. Yet, a staggering "55% of Ohio's agricultural soils need surface or subsurface drainage improvements" (Bierman). Clearly, conservation is appropriate in such circumstances, so that a reduction in average water use per household in Ohio, for instance, could translate into availability of water to address the requirements of subsurface drainage improvement. This aligns perfectly with the assertion of the Massachussetts Water Conservation Standards that "water savings that result from increased efficiency can, in effect, serve as a new water source". The interconnectivity of successful application of water conservation in irrigation, and the efficiency of overall water distribution is poignantly reflected in the assertion that "water conservationcan provide an economically competitive advantage for public water suppliersreducing operating and maintenance costs, reducing wastewater treatment costs, freeing up plant capacity for pumping and treatment of water and wastewater,avoiding the considerable cost of investing in new sources of water" (Massachussetts Water Conservation Standards 5). The source further notes that "water can conservation can significantly improve the performance and longevity of septic systems, benefitting the users" . Perhaps the natural starting point for addressing efficiency within the water distribution system (which incorporates the entire irrigation process)should be a review of the attitude towards naturally-occurring water, particularly rainfall. In our contemporary world, there are still too many parts of the world where "rainfall sweeps across deforested lands,..Runoff rages through concrete cities. Rivers are drying up, water tables are falling. Rivers that once supported ecosystems are barren"(Payne and Neuman). Rainwater, accorded its proper place, effectively harnessed and managed , can function to a very significant extent as source water in the distribution system. The division and sharing out of this source water, when wastage is totally minimised or eliminated- helps to establish the process of efficient distribution. A miniature, test-project in Ohio demonstrated that, a proper attitude to saving rainwater was able to provide steady water- through subirrigation channels/subsurface drainage systems- by saving water during and immediately after rainfall, into wetland. This water water was then pumped into a water supply reservoir for storage and later pumped to subirrigation /subsurface drainage systems (Ohio State University bulletin). Conclusion The forgoing has analysed irrigation in the context of water conservation, rain harvesting and efficient water distribution. It establishes that, contemporary irrigation needs to revisit its relationship with conservation of its essential element-water- to achieve its essential end. Indeed, water conservation resulting in efficient distribution should ideally be the objective of modern irrigation. Around the world- from North America to Asia- conservation techniques have justified (through results ) the view that, as far as irrigation is concerned, simple-and-basic, reuse-and -recycle is the way to go. It is also apparent from the above that water distribution efficiency is interconnected with proper water conservation as applied to irrigation- the world's largest user of water- such that water saved from irrigation becomes available in other parts of the overall water distribution network. A more respectful attitude to naturally-occurring water, and a reduction in water consumption- indoor and outdoor- is necessary everywhere, particularly (and paradoxically) in areas apparently blessed with abundant water supply (particularly rainfall), such as Ohio. Abstract This project analyses and addresses the problem of water conservation in irrigation, as well as its bearing on the efficiency of water distribution in general. The approach begins with a consideration of irrigation's essential nature and objective, against the background of global availability (or otherwise) of the essential resource (usable water). This led to a consideration of water conservation techniques as applicable and relevant to contemporary irrigation. In the process, water conservation's environmental drawbacks were considered, as well as those of modern irrigation, and how these drawbacks (in either case) are avoided to achieve irrigation's ends, with a view to establishing the more environment-friendly mode of irrigation. The impact of the various methods on water distribution was also analysed, in the process. The methodology has made use of relevant literature as research material. TITLE PAGE IRRIGATION AND EFFICIENT WATER DISTRIBUTIONTHROUGH CONSERVATION AND RAIN HARVESTING TABLE OF CONTENTS 1. Introduction 2. Water Conservation- Importance And Primary Objectives 3. Rain Harvesting And Water Conservation- Usefulness And Applicability In Irrigation 4. Water Consumption And Its Crucial Role In Efficient Water Distribution 5. Conclusion Bibliography Ward, Frank and Pulido-Velazquez Manuel, "Water Conservation In Irrigation Can Increase Water Use". 17 March 2010 Bierman, Peter "Soil And Water Resources" OSU Piketon Research And Extension Center 23 March 2010 Massachusstes Water Standards/Executive Office of Environmental Affairs And Water Resources Commission, July 2006 21 March 2010 Brookefield, Maryan Alyce, "Environmental Landscaping: An Analysis of The Means of Water Conservation As Pertains To Irrigation And Landscaping At Occidental College: The Implementation of Centralized Irrigation, or Gray water, Storm Water or Recycled Water Reuse System." 20 March 2010 Payne, Troy and Neuman Janet, "Rembering Rain". Journal Title: Environmental Law. Vol. 37., Issue No. 1. Publication Year: 2007 Noah, Marilyn, "Graywater Use Still A Gray Area". Journal of Environmental Health. Vol.64. Issue No. 10. Publication Year: 2002 Morris, John "Pricing For Water Conservation", Journal: Contemporary Policy Issues .Vol 8. Issue No. 4. Publication Year: 1990. Pg. 88 The FAO Corporate Document Repository, "The Practice of Irrigation" 23 March 2010 Ohio State University Bulletin, "Agricultural Drainage". Bulletin 871-98 21 March 2010 Texas Water Matters, "Water Conservation". 22 March 2010 Water Use In Ohio, 21 Marxh 2010 Literature Review The cited sources for this work have addressed different compartments of the topic. Therefore a review of their contributions must make allowance for the fact that they have looked at different angles that make up the subject matter. The Massachusetts water standards ("Water Conservation Standards") appears to be quite strong on water conservation enhancing water distribution efficiency. It however appears that Morris' cautionary approach towards endorsing water pricing is absent in the disposition of the Massachusetts Water Standards. Texas Water Matters ("Water Conservation") makes a very strong statement (case) for water conservation, and makes it forcefully clear that its assertions are empirically-based- a level of forcefulness absent in the tone of the source"Water Use in Ohio". Payne and Neuman ("Remembering Rain") have presented a description of water conservation processes as well as scenarios depicting application. They have also made available details that constitute good reason for a more serious attitude toward rainwater management. The Ohio State University has provided a useful case study that however has a 'laboratory' a approach in its presentation. This contrasts somewhat with Bierman's presentation ("Soil and Water Resources"), which comes across as rooted in many years of agricultural experience coupled with academic application. Noah occupies perhaps too much of a "middle ground" position on the subject of graywater use- should be a bit more decisive on leaning/conviction. Marilyn Brookefield ("Environmental Landscaping: An Analysis of...") has a rather restricted approach, centering the treatment around everything pertaining to a university campus environment in Florida. This doesn't seem to give it a general, broad view on the subject. The FAO's contribution is very precise on statistics, and uses this very effectively to highlight the critical need for water conservation consciousness. Read More