Irrigation Pipe Research Articles

New technologies for modernization and management of irrigation piping

Improving the efficiency of irrigation piping-systems represents a fundamental prerequisite to achieve a sustainable irrigation under both the environmental the economic point of view. Such an issue is important not only in areas with limited water-budget, but even in those areas where the increasing reduction of the water availability has become a worrying perspective. In the last twenty years, the reduction in water-availability and the increasing costs of system-management have highly limited the cultivated areas which are irrigated by means of water-distribution nets. In the recent years, most of the Italian investments in the irrigation-field have been oriented toward upgrading the open-channels irrigation nets, which were built starting from 50’, by substituting these latter with pipes. The modernization of the piping-systems has been achieved via innovative design solutions, such as back and loading water tanks or towers, which have lead to an improvement into the flexibility of the net management. Nearby the employment of such technologies, nowadays it is also possible to use the knowledge of the physical processes involved in the management of an irrigation system, starting from energy as well as mass exchange in the continuum soil-plant-atmosphere till to a detailed hydraulic description of a water distribution net under different flow regimes. Such a type of knowledge may be used to improve as well as buildup mathematical models for a decisions-support toward the management of complex irrigation districts. The acquirement of the data needed to implement such models has been deeply improved thanks to Geographical Information Systems (GIS), and techniques to analyze satellite-data coming from the Earth observation, which enable to characterize and monitor vegetation at different spatial, spectral and radiometric resolutions.

Ranch Hands

Ranch Hands Kate Dernocoeur (bio) Sweat stings my eyes, and my breath comes hard at 4,100 feet, but damned if I’ll quit sawing. Muscle burn in my arm and shoulder confirms the toughness of the foot-thick cedar crushing the barbed wire fence that we’re here to fix. “You want a break?” calls Jim from upslope, where he and his wife, Peg, are grappling with a tangle of wire. Behind them, the fence line threads to the horizon. After this section is repaired and restretched, we’ll follow it up there and for another mile beyond in the couple of days we have left. “Nope,” I manage to say. “I’ve almost got it.” This is my first day back at Lone Indian Ranch, and I’m ready for this. Backhanding the sweat, I’m satisfied by the stain it puts on the purple leather of the work glove. My cousin Kathy knows I always forget gloves, always has some for me to use. But this trip, she’s gotten me a brand new pair. They are too stiff, and I don’t like how the color seems like something only a dude would wear. The metal teeth of the saw can only chew so much wood at a time, so it’s useless to press down. I imagine my arm is a piston moving back and forth, powered by the steady two-stroke punch of my raspy breath, in, out. At last, the big tree yields. While Jim and Peg climb down to me, I raise the other glove to my forehead, sweat-stain it too, and smile. It takes the three of us to heave the cedar tree over the crushed fence line, out of the way. Uphill, from the shade of the pickup truck, the four dogs sit up to watch the commotion for a moment, then lie back, panting, against the cooler earth. This parched hillside is nothing like the greener pastures of the bottomland [End Page 61] where, earlier this morning, Kathy, Peg, and I walked out to Lower Sweetgrass Road. It’s three-quarters of a mile from the ranch house to the mailbox, and 17 miles on gravel road from there to the town of Big Timber. All of this is worlds away from my softer life several hours by plane east of here. I’m easily lured back to Montana, been out here many times to help with such tasks as lambing, cattle branding, irrigating. This trip, it’s fencing. I’m new to this essential ranching chore. Fencing altered the West, tamed it. I understand the need for a bit of order, even here on the open range. The ranchers I’ve met—as independent as they can be—are oddly reassured by the straightness of a good fence line, grateful for it when the time comes to funnel livestock down from summer grazing to the barnyard. This short section of fence line was restretched yesterday, before I arrived, but the five strands of barbed wire still need to be clipped to the posts. My tutorial was brief, typical: “Hold the pliers like this and bend the clip under like this,” Kathy said. Using her fencing pliers like a conductor’s baton, she had smoothly wrapped the clip around the green metal post. Looked simple enough. She hadn’t waited around to see if I got it. Grabbing a shiny new V-shaped clip, I had turned to the fence. Clips are made of stiff heavy-gauge wire, beefier than a clothes hanger, designed to fit the green, triangular posts that ranchers use now instead of excavating cedar post holes in this unforgiving ground. Done right, a clip hooks the barbed wire so that it effectively hugs the post. It shouldn’t have been hard. What is hard, actually, is the day-in, day-out life Kathy has led here for decades with her rancher husband, Lyle. In winter, there’s the cold trek to the lambing and calving sheds every two hours, day and night. In summer, there’s the manual repositioning of crop irrigation pipes several times a day, at least until the Sweetgrass River runs...

Feasibility Evaluation of Pressurized Irrigation in Canal Commands

India has one of the largest and most ambitious irrigation programme in the world with net irrigated area exceeding 47 million hectares. However, the overall project efficiency from the headwork to the farmer’s field has been quite low which leads to not only poor utilization of irrigation potential created at huge cost, but also aggravates the degradation of soil and water resources and thereby endangers the sustainability of agricultural production system. As the cost of creating additional irrigation potential in terms of financial, human and environmental aspects has increased tremendously, need of the hour is to increase the irrigation efficiency of existing projects and use saved water for irrigating new areas or meeting the demand of non-agricultural sector. The contribution of application efficiency to poor irrigation efficiency is quite high and therefore increasing application efficiency by a shift in application method from surface to pressurized system has potential of vastly improving irrigation efficiency. To evaluate feasibility of this concept, a pilot study was initiated at Water Technology Centre for Eastern Region, Bhubaneswar, on one outlet of a minor irrigation command. The system has been designed in such a way that it provides pipe conveyance and surface irrigation for rice cultivation during monsoon season and pressurized irrigation during post monsoon period through a hybrid system of sprinkler and drip with four outlets for sprinkler irrigating 2.8 ha area and two outlets for drip irrigating 1.9 ha area. The system is also capable of providing irrigation through drip to part of a command during summer for third crop using water stored in service reservoir after the canal is closed in first week of April. To take care of sediment in the canal water, there are three stages of filtration: first by hydrocyclone filter which filters heavy suspended materials viz. sand, silt, etc., then by the sand filter and finally by the screen filter. The filtration at three stages reduces the turbidity to the desired level. It has been found that three-stage filtration reduced the turbidity to two NTU which is within permissible limit. Considering the cost of water saved, a benefit-cost ratio of the system was found out to be 1.126. This B: C ratio can be further increased by increasing the productivity of the fish and papaya in service reservoir area and better crop management during summer season.

Design and analysis of a swinging drag body flowmeter for irrigation pipe

A swinging drag body flowmeter was designed and tested under laboratory conditions. The meter was designed to measure flowrate in an irrigation water pipe. The meter consisted of a paddle, a rotating mechanism, and a potentiometer to measure paddle position. The rotating mechanism was mounted in a head unit that was strapped to a water pipe. The paddle extended from the rotating mechanism at the pipe wall, down through the center of the pipe. Drag and lift formulas were used to analyze flowmeter behavior and determine if these equations could be used to develop other flowmeters of this design. The lab data showed a strong correlation to the theoretical equations but there were significant errors between the two sets of data. The meter behaved in a repeatable and stable manner over two months of lab testing. It is believed that this design is particularly suited for irrigation pipe flow applications.

Mediating N 2O emissions from municipal solid waste landfills: Impacts of landfill operating conditions on community structure of ammonia-oxidizing bacteria in cover soils

Chemolithotrophic ammonia-oxidizing bacteria (AOB) can produce N 2O, a highly potent greenhouse gas. Denaturing gradient gel electrophoresis (DGGE) analyses of the ammonia monooxygenase structural gene ( amoA) and 16S rDNA gene were used to investigate the AOB community structure in the cover soils of municipal solid waste (MSW) landfills under three operating conditions: (a) MSW with soil cover, (b) MSW with soil cover, irrigation piping and vegetation, and (c) MSW covered with high-density polyethylene (HDPE) liner, soil cover, irrigation piping and vegetation. AOB species in MSW cover soils were significantly distinguished by the operation of HDPE liner isolation. The community structures of the Nitrosomonas europaea-like AOB species dominated in soils without HDPE liner isolation, whether vegetation and irrigation with landfill leachate existed or not, whereas Nitrospira-like AOB species dominated in soils with HDPE liner isolation. Lower N 2O flux from the soils with HDPE liner isolation would be partially related to these special community structures.

Measured and simulated soil wetting patterns under porous clay pipe sub-surface irrigation

Sub-surface irrigation with porous clay pipe can be an efficient, water saving method of irrigation for many less developed arid and semi-arid regions. Maximizing the efficiency of clay pipe irrigation requires guidelines and criteria for system design and operation. In this study, experimental and simulated (with HYDRUS (2D/3D)) soil wetting patterns were investigated for sub-surface pipe systems operating at different water pressures. Predictions of the soil water content made with HYDRUS were found to be in good agreement ( R 2 = 0.98) with the observed data. Additional simulations with HYDRUS were used to study the effects of various design parameters on soil wetting. Increasing the system pressure increased the size of the wetted zone. The installation depth affects the recommended lateral spacing as well as the amount of evaporative water loss. For a given water application, the potential rate of surface evaporation affected the shape of the wetted region only minimally. Soil texture, due to its connection to soil hydraulic conductivity and water retention, has a larger impact on the wetting geometry. In general, greater horizontal spreading occurs in fine texture soils, or in the case of layered soils, in the finer textured layers.

Valmont Industries, Inc

This case serves as an introduction to the concept of economic value added (EVA). The student is placed in the position of Valmont's CFO to decide whether EVA can live up to its promise to motivate managers to act like shareholders and ultimately lead them to make value-enhancing decisions that can reverse Valmont's weak earnings and lackluster stock-price performance. The case works best if students are acquainted with the concepts of cost of capital and net present value. The teaching note that is available for registered faculty explains how to incorporate the accompanying six-minute video supplement. Excerpt UVA-F-1191 Rev. Feb. 1, 2011 VALMONT INDUSTRIES, INC. Forty years ago, we made our first center pivot irrigation system. It was essentially a long steel pipe resting upon a set of wheels that would travel in a circle, watering crops. A few years later, we stood that irrigation pipe on its end and made our first light pole. It was our first lesson in leverage. It wouldn't be our last. —Valmont 1993 Annual Report After being one of the most successful Fortune 500 companies during the 1980s, Valmont Industries fell on difficult times in the 1990s. For the period 1990–92, Valmont's earnings fell well below the company's peak year of 1989, and Valmont management believed that the company's stock had fallen out of favor with Wall Street (Exhibit 1). Although Valmont management fought back by cutting costs, restructuring, and spinning off segments of its business, by the summer of 1993 there was still no tangible evidence that the tide had turned. . . .

Potential sources of Pythium inoculum into Greenhouse Soils with no Previous History of Cultivation

AbstractA study was undertaken to investigate the potential sources of Pythium inoculum in greenhouse soils. About 7% of fallow soils were found to harbour Pythium before being introduced into greenhouses. When replacing the top layer (30–60 cm) of cultivated soil in greenhouses with fallow soil, Pythium inoculum was still recovered from the bottom layer of soil left in the greenhouse. Other potential sources of Pythium were found to be potting mixtures and contaminated soil adhering to cultivation equipment, growers’ shoes and reused irrigation pipes. Pythium isolates from different sources were from two species: Pythium aphanidermatum (88%) and P. spinosum (12%). This appears to be the first report of transmission of Pythium via contaminated soil adhering to reused irrigation pipes. It also represents the first report in Oman of transmission of Pythium into greenhouses via potting mixtures and fallow soils.

Subsurface Porous Pipe Irrigation with Vertical Option as a Suitable Irrigation Method for Light Soils

Subsurface Porous Pipe Irrigation with Vertical Option as a Suitable Irrigation Method for Light Soils

Water-saving Technologies, Solar Green House and Ecological Rehabilitation in Minqin Oasis of Gansu Province, China

Abstract Land degradation and desertification have become severe environmental problems in arid areas due to excessive use of water resources. It is urgent to reduce agricultural water use for ecological rehabilitation, which may result in a decrease in agricultural production and farmer’s welfare. This paper focused on the impacts of some main measures including extensions of water-saving irrigation, expanding solar green house and increasing off-farm employment, which are generally recognized to be important to alleviate water shortage and poverty. A bio-economic model is applied taking Minqin Oasis in Gansu Province as a case study site. Simulation results showed that the effect of expanding solar greenhouse was more positive than other ones so it drew more attention. On the view of the different effects between each irrigation zone, mixed policy patterns suitable for them are suggested. In Baqu, expanding solar greenhouse should be the most important, auxiliary with encouraging pipe irrigation. Invers...

Evolução do N residual e do pH num Podzol da Campina de Faro, por efeito da fertirrega gota-a-gota num pomar de jovens laranjeiras

A young ‘Lane Late’ orange orchard grafted on ‘Carrizo’ citrange was planted in 1999, in a Gleyic Podzol, located at Campina de Faro (Algarve), with the application of five N rates, applied through drip fertigation, in increasing levels throughout 3 years (N1 - 10, 15, 20; N2 -20, 30, 40; N3 - 40, 60, 80; N4 - 80, 120, 160; N5 - 160, 240, 320 g N per tree). Annually, in the beginning and in the end of each cultural cycle, soil samples were collected, in the wetted zone, for chemical characterization. The main objectives of the present work were to study the evolution of residual soil N and pH. Residual N in the soil was not significantly affected by N rates, decreasing gradually with the depth, as it was expected in such a sandy soil (96% of sand). Nitrogen was significantly affected by the sampling date, N rate and depth, particularly for nitric N, which decreased at the end of each winter, in consequence of the rainy season. Nitrate levels were significantly greater for the higher N rates, suggesting that such rates were excessive. In the end of the 1st year soil pH increased significantly, probably due to the continuous and localized supply of alkaline irrigation water, rich in HCO3-, Ca2+ and Mg2+. At the end of the 2nd and 3rd years, soil pH maintained identical value as for the initial soil pH, which can be explained by the increasing levels of acidifying fertilizer applied, as well as the acidifying solutions used to clean the irrigation pipes. As for the concentration of the remaining nutrients, although there were significant differences, the values determined in the soil samples were low or very low, not contributing to plant nutrition.

Function of permeable geosynthetics in unsaturated embankments subjected to rainfall infiltration

This paper presents laboratory tests and experiments using scale models to study the hydraulic behavior of permeable geosynthetics within unsaturated embankments subjected to rainfall infiltration. Water retention curves were measured in the laboratory in order to evaluate the unsaturated hydraulic characteristics of soil and geosynthetics. Model embankments were built using two layers of permeable geosynthetics; rainfall was simulated using an irrigation pipe. Embankments were subjected to wetting and drying processes; negative and positive pore water pressure and water contents within the model were measured. Comparison between Tempe pressure cell and hanging column test results showed that geosynthetics embedded within the soil approached saturation only when the pore water pressures of the surrounding soil were close to zero or positive. This behavior was also observed in the model tests. Local failure during the wetting processes was observed while pore water pressure increased immediately above the geosynthetic layers. In the models, where strips of geotextile were used, water could not accumulate above the geotextile, and instead drained down between strips. Strips of geotextile prevented the capillary barrier effect and allowed the free drainage of water through the embankment.

Development of Prediction Models for Friction Losses in Drip Irrigation Laterals equipped with Integrated In-line and On-line Emitters using Dimensional Analysis

This paper presents models developed to predict friction head losses in drip irrigation laterals. Some domestic and imported drip irrigation laterals equipped with integrated in-line and on-line emitters placed at different spacings ranging from 0·2 and 1 m were considered in this study. The parameters affecting the variation in friction head losses in laterals were defined as dimensionless terms using Buckingham's Π theorem. Two mathematical models were developed in this study. In order to develop a model for integrated in-line emitters, experimental friction head losses data from 16 different drip irrigation pipes with above-mentioned spacings were used and the model developed accounted for 98·53% of the variation in the data. Another model developed was for predicting the friction head losses in laterals with on-line emitters. For the development of a model, experimental friction head losses data from six different drip irrigation pipes equipped with on-line emitters with above-mentioned spacings were used. The model developed for on-line emitters was able to explain the 98·76% of the variation in the data collected in the laboratory. The developed models in this study for in-line and on-line emitters were compared against the models available in the literature in terms of total friction head losses and lateral lengths. It was found that the total friction head loss differences between the developed model and the model existing in the literature were small and varied between −1·7% and +1·7% for in-line emitters while the same comparison for on-line emitters indicated a range between −0·9 and +1·9%. The results showed that the developed mathematical models may be used to determine the friction head losses in drip laterals with integrated in-line and on-line emitters placed on laterals at different spacings ranging from 0·2 to 1 m.

Construction of a Maintenance History Management System for Irrigation Pipe Lines Using GIS

Construction of a Maintenance History Management System for Irrigation Pipe Lines Using GIS

Surface Irrigation of Dairy Farm Effluent, Part II: System Design and Operation

Dairy farms with as many as 200 cows still handle their wastewaters and solid manures separately. Because of the large volume produced and their low nutrient load, these dairy farm effluents (DE) are costly and time consuming to land spread using conventional equipment, such as the tanker. The purpose of this study was to test the equipment and cost to determine the cost of the equipment adapted for the simplified surface irrigation of DE and to establish best management practices to reduce risks of groundwater contamination. The project was conducted on two dairy farms in South Western of Montreal, Canada, where typical DE were applied to irrigated plots of 0·5 and 0·3 ha, respectively, and the groundwater quality was compared to a control plot of the same size. Groundwater quality was monitored for nutrients (total nitrogen, total phosphorus, total potassium and pH) and bacterial counts (total coliforms, faecal coliforms, and faecal streptococci). A manure pump and conventional water irrigation pipes were satisfactory in irrigating with the DE without clogging as long as the DE was collected in a tank separate from that of the solid manure. During all applications, subsurface seepage losses occurred, but these would not be lost to the watercourse when applied in quantities respecting irrigation guidelines and on soils where the groundwater table was at or below the depth of the subsurface drains. Nevertheless, these seepage losses represented less than 1% of the total volume of DE applied, and the seepage nutrient and bacterial load was generally less than half of that of the irrigated DE. The surface irrigation system reduced the cost of land spreading DE from CAN $3·25 m−3 (conventional tanker) to CAN $1·10 m−3 (surface irrigation). The heavy total potassium load of the DE requires the rotation of the irrigation plot, on an annual basis.

EFFECT OF INCREASING THE DISSOLVED OXYGEN IN THE NUTRIENT SOLUTION TO ABOVE-SATURATION LEVELS IN A GREENHOUSE WATERMELON CROP GROWN IN PERLITE BAGS IN A MEDITERRANEAN AREA

EFFECT OF INCREASING THE DISSOLVED OXYGEN IN THE NUTRIENT SOLUTION TO ABOVE-SATURATION LEVELS IN A GREENHOUSE WATERMELON CROP GROWN IN PERLITE BAGS IN A MEDITERRANEAN AREA

Estimativa do custo de implantação da agricultura irrigada, utilizando o sistema de informação geográfica

A proposta deste trabalho foi utilizar o Sistema de Informações Geográficas (SIG) com o objetivo de indicar áreas agroeconomicamente mais aptas para a implantação da cultura do coqueiro irrigado. Foram utilizadas informações referentes ao assentamento rural Antonio Farias, localizado no município de Campos dos Goytacazes, região Norte do Estado do Rio de Janeiro. O software IDRISI 32 gerou informações que técnicos, extensionistas e produtores rurais podem utilizar no planejamento da agricultura em áreas irrigadas. Foram utilizados mapas digitais de solo e planialtimetria, além de mapas temáticos com informações de drenagem, estradas e limite dos lotes. A partir de operações de sobreposição dos temas solo, clima e relevo, foram criados novos mapas temáticos, que mostram os gastos parciais para implantar 1 ha irrigado da cultura do coqueiro-anão. O gasto de implantação foi composto pela soma dos desembolsos para a compra de calcário, fertilizantes, tubulação e moto-bomba. A partir dos mapas criados, foram observadas variações expressivas nos desembolsos para implantação de 1 ha de coqueiro irrigado entre os lotes do assentamento. Foi possível observar que a metodologia utilizada se mostrou eficaz na identificação das áreas mais aptas, sob o ponto de vista agroeconômico, para a implantação de culturas irrigadas, sendo facilmente aplicável para outras culturas e áreas de estudo.

Modified Hazen–Williams and Darcy–Weisbach Equations for Friction and Local Head Losses along Irrigation Laterals

In previous analytical approaches, the direct calculation of friction loss along a lateral is usually based on empirical power-form flow resistance equations, such as the Hazen–Williams and Blasius equations. The more generalized Darcy–Weisbach resistance equation is not usually applied since its friction coefficient varies along the lateral. In this paper, initially, the Darcy–Weisbach and Hazen–Williams equations are systematically compared, leading to a correction form for the Hazen–Williams coefficient. In addition, a more accurate procedure assuming a power function form for the Darcy–Weisbach equation along irrigation laterals is also proposed. The systematic analysis of various typical flow pipe irrigation situations (e.g., sprinkler irrigation laterals of linear or radial-center pivot displacement, trickle irrigation laterals, and manifolds) indicates that the friction loss along laterals calculated using the Darcy–Weisbach equation closely follows a discharge-power form function. The two empirical parameters of the power function depend on the specific pipe characteristics as well as the specific range of discharge values along the lateral. The proposed analytical solution is extended to incorporate the local head loss, the velocity head variation, and the outflow nonuniformity along sprinkler and trickle irrigation laterals. The suggested direct computation solution is demonstrated in two application examples of sprinkler and trickle irrigation laterals and compared with accurate numerical solutions.

Application of Conditioner Solution by Subsurface Emitters for Stabilizing the Surrounding Soil

Poor uniformity of water application by subsurface drip irrigation has been examined and some explanations are suggested in this paper. Use of soil conditioners for soil structure stabilization around subsurface drip irrigation pipes was suggested by the authors and tested in the laboratory. The conditioners preserve the structure of existing aggregated and may effectively reduce soil clogging. A silt loam soil was uniformly packed in a 13 0.83 0.15 m box. Two holes were dilled in the box wall through which two emitters were inserted, one for applying solution of soil conditioner and one as a control. Stabilization was achieved by applying two types of polymer solutions differing by their molecular weights through an emitter buried in a silt loam soil. A measured water volume was injected through the emitters into the soil and, after 48 h following irrigation, the box was dismantled. Gravimetric soil moisture content and aggregate water stability were measured in vertical and horizontal distances from the emitter. The highest stabilizing effectiveness was obtained with a volume of 1.5 L polymer solution at 5 g / L concentration, which was applied to the soil at an initial moisture content of 13%. The volume of stabilized soil increased with the volume of applied solution, but the volume ratio of stabilized soil to applied solution decreased with the increase in solution volume. A polymer of relatively low molecular weight was found less effective since a large portion of the solution was consumed by fast penetration into soil aggregates without improving the soil structure. The proposed method offers a simple and easy means for preparing a stabilized soil envelope around subsurface drip irrigation pipes, which may improve the long-term performance and uniformity of the application of these systems. Yet for some of these aspects, further field evaluation is needed, since the results of the study are from a laboratory experiment limited to one soil only.

Assessment of slope stability in Ankara clay: a case study along E90 highway

Some slope instability problems exist in Ankara clay along E90 highway. The purpose of this paper is to determine the mineralogical and geotechnical properties of soils, and to investigate the causes and mechanisms of three rotational landslides along a section of the highway. In order to accomplish these tasks, field studies, laboratory testing, back analyses, and limit equilibrium and finite difference analyses were performed. The landslides are formed within a soil consisting of clay and silt with a little sand and gravel. Slope stability analyses indicate that long-term stability of already failed slopes is critical. The failures are progressive, showing strain softening behavior with full saturation. Broken irrigation pipes existing near the landslides are found to be the main cause of sliding. Maintenance of the pipes, surface drainage, removal and replacement of the failed (slided) material are considered to be economical and practical solutions for the remediation of the slides.