Seepage Losses Research Articles

STUDI ANALISIS EFISIENSI DAN KEHILANGAN AIR PADA SALURAN IRIGASI KAMPUNG REJE GURU KECAMATAN BUKIT KABUPATEN BENER MERIAH

D.I. Reje Guru is an open system irrigation network located in Bukit District, Bener Meriah Regency, Aceh Province. Various problems were identified such as cracked lining and wild vegetation around the network. These issues have impact on water losses along the channels’ conveyances through evaporation, seepage, operational factors and leakage. The input – output discharge measurement is used to determine the water loss and the value of the efficiency of water distribution in the Irrigation network. In addition, the evaporation and seepage loss are also calculated to find out the percentage of the loss from these two factors. The results shown that the maximum and minimum loss is from BS3RG and BS4RG which are 0,027 m3/sec and 0,004 m3/sec, respectively. The values are correlated to the efficiency values which are the highest 84,23% from BS4RG and 36,908% from BS3RG. It is confirmed that the two factors of evaporation and seepage are not the significant factor to the conveyance water loss.

Estimation of seepage losses from cracked rigid canal liners using finite element modeling

This study numerically investigates the effect of cracks in rigid canal liners on seepage control. Firstly, the case of a single crack is analyzed for different locations and widths then, the case of multiple cracks is examined. The results show that a single crack in a rigid canal liner increases the seepage losses by 2.3–4.6 times its value in an un-cracked liner, just under the canal’s bed, depending on the crack’s location, with the maximum value occurring when the crack is at the bed’s centerline. The crack’s location has a negligible effect on the deeper soil. The amount of seepage from the lined canal is directly proportional to the crack’s width. Multiple cracks drastically reduce the liner’s efficiency, where cracks with total widths of 3, 4, 5, and 6% of the canal bed width cause losses approaching 65.57%, 76.80%, 86.67%, and 87.79% of those from the unlined canal.

Economic Importance of Different Sealant Materials for Seepage Loss Control of Water Harvesting Pond under Irrigated Condition

Economic Importance of Different Sealant Materials for Seepage Loss Control of Water Harvesting Pond under Irrigated Condition

In-Situ Leaching Mining Technique for Deep Bauxite Extraction and the Countermeasures for Water Pollution Prevention: An Example in the Ordos Basin, China

As the second most significant metal following steel, aluminum plays a vital role in the advancement of both strategic emerging industries and national economic development. The existing oil and gas drilling data indicate that the deep bauxite deposits is abundant around the Ordos Basin in China, at the depths ranging from several hundred meters to several kilometers. Based on the geological and hydrogeological characteristics analysis, it is found that deep bauxite deposits in the basin have distinct electrical characteristics, characterized by four highs and two lows. While there is scarcity of prior research on the exploration topic for the technique limitation. In this paper, a logging interpretation model has been developed, which allows the evaluation of bauxite deposits. An efficient technology was proposed for deep bauxite exploration, utilizing an in-situ leaching mining technique. This technology is well-suited to the geological conditions of the Ordos Basin, ensuring that the solution flows within the bauxite ore bed without any seepage loss. To prevent the leaching solution from seeping into and polluting the main aquifer around the basin, several measures have been proposed. These include filling with polymer resin, well pattern seepage control plugging, and establishing monitoring systems. The results of this study provide a theoretical basis for the adoption of environmentally sustainable mining techniques and the mitigation of water pollution in deep bauxite exploration.

Forecasting the seepage loss for lined and un-lined canals using artificial neural network and gene expression programming

Canal lining is customarily used to raise water-use effectiveness and reduce seepage loss. The major water losses in an irrigation channel are due to leakage and evaporation. The Egyptian General Integrated Management for Water Resources and Irrigation introduced a proposal for lining the Al-Hagar canal based on these losses. This study investigates the effect of lining in the Al-Hagar canal on flow characteristics, and compares the canal before and after introducing the lining. Additionally, it discusses the most common type of water loss, namely, losses due to seepage. Fieldwork was conducted on the Al-Hagar canal, Al-Saff Center, South of Helwan city, Egypt. The result revealed that the discharge of the canal after the lining is approximately 1.362–1.573 times greater than that of the un-lined section. Water losses in the Al-Hagar canal were 38.736% when un-lined but decreased to 29.253% when lined. The conveyance effectiveness in the un-lined canal, which is approximately 61.26%, increased to 70.75% when the entire canal is lined, which means a 9.483% improvement of conveyance. New relations were introduced using Artificial Neural Network and Gene Expression Programming to forecast the seepage loss in the lined and the un-lined canal as a function of Manning’s coefficient, Froude number and hydraulic radius. The consequences were better using the GEP program than using ANN for the lined and the un-lined canals. The value of the determination coefficient was 0.98, Correlation factor was 0.99, and the RMSE was 0.0017 for lined canals and the value of determination coefficient was 1, Correlation factor was 1, and the RMSE was 0.0003 for un-lined canals.

The use of empirical equations for seepage estimation in comparison with observed losses from irrigation canals

This study analyses and presents a technical comparison of seepage estimation from 11 empirical equations with measured seepage losses by the inflow-outflow method from two lined and unlined secondary irrigation canals sub-divided into different reach lengths. A significant margin of error was observed between empirical and inflow- outflow methods, hence modifications in empirical equations were performed. Results reveal that the average seepage losses observed in unlined and lined canals by inflow-outflow method were 9.15 and 3.89%, respectively. Moreover, only the Chinese equation estimated seepage losses for an unlined canal as similar to observed losses (0.11 m 3∙s –1) whereas the Indian equation estimated similar results for a lined canal to those observed in the field (0.09 m 3∙s –1). However, the rest of empirical equations were modified in accordance with error percentage with regard to the observed losses. The empirical equations were then observed to estimate reliable results of seepage.

Economic Importance of Different Sealant Materials for Seepage Loss Control of Water Harvesting Pond under Irrigated Condition

This study was carried out in order to identify low-cost and efficient sealant materials for water harvesting ponds. An extensive cost comparison study of sealant materials was conducted, taking into account seepage reduction and farm income loss. Four seepage control materials were evaluated in terms of their financial cost. The cost analysis was conducted in terms of farm income loss when three crops' water productivity (kg/m 3 ) were considered potato, onion, and wheat; 1.13, 10.57 and 5.27 kg/m 3 of wheat, potato and onion, respectively. The cost of sealant materials includes the capital cost of material and labor for purchase and application in water harvesting ponds. The cost-benefit analysis result of sealant materials (compaction, mortar, ash, and bentonite) were compared for the next ten years and gave a significant farm income. For this study a water harvesting pond having a volume of 4,792 m 3 was considered to cultivate (wheat, potato, or onion) for one cropping season under irrigated conditions. A farm pond managed by; bentonite and Ash can save 23 % and 43 % than control treatment respectively. The saved irrigation water used to cultivate wheat, potato, and onion crops in 1 ha of land for one cropping season can bring an additional farm income of about 317,632 ETB with Bentonite and 226,798 ETB with Ash when compared to the compaction alone treatment (control). Analysis of cost and income over ten years productivity period showed that, the maximum cost of sealant materials to cover a volume of 4,709.69 m 3 requires at least four years investment period to achieve the breakeven point (189,600 ETB), that corresponds to the point at which the cost of sealant materials equals the resulting farm benefits. Therefore, investing in sealant materials for control seepage lose from water harvesting ponds will give a profit of their investment after four and above project years. Keywords: Cost Effective, Sealant Material, Water harvesting, Water loss DOI: 10.7176/RJFA/14-9-01 Publication date: May 31 st 2023

The Seepage Evolution Mechanism of Variable Mass of Broken Rock in Karst Collapse Column under the Influence of Mining Stress

When the collapse column of overburden is disturbed by the working face, the grain loss in the karst collapse column occurs by the dissolution and corrosion of groundwater, thereby inducing the water inrush disaster. The test samples are prepared based on the fractal theory and the Talbol grading theory, and the seepage evolution law of fractured rock in collapse column under triaxial stress is studied, by employing the triaxial seepage test equipment. Besides, the seepage mechanics model of broken rock is established and calculated in the COMSOL Multiphysics, and the water-conducting channel under mass loss condition in the collapse column is further elucidated. The research results indicate that the loss ratio of mass is inversely proportional to the Talbol power index, and grain mass loss rate increases with the decrease of the Talbol power index. During the infiltration process, the evolution of pore structure is related with grain size distribution. With the increase of the Talbol power index, the overall porosity increases. Grain loss is an internal factor in seepage loss stability. Flow speed is accelerating, and seepage pathways are communicated with each other to induce the water inrush disaster.

Evaluation of hydraulic efficiency of lined irrigation channels – A case study from Punjab, Pakistan

Abstract Indus Basin Irrigation System (IBIS) in Pakistan is the backbone of agriculture in the country. The IBIS provides irrigation support to agricultural lands across the country; however, hydraulic efficiency of the water conveyance system is impacted due to seepage losses. The lining of irrigation channels is considered a potential solution for improving hydraulic efficiency. Therefore, this study explores the impact of canal lining on the hydraulic efficiency of the canals in the Punjab province of Pakistan. Overall, 14 channels/distributaries/minors (total length 226 km) were monitored in terms of hydraulic performance in different irrigation zones. Hydraulic, geometrical, and socioeconomic parameters of channel/distributaries/minors including roughness coefficient, sediments, flow velocity, wetted parameter, breaches, theft cases, bed, side slope, water surface profile, hydraulic radius, crop yield, and vegetation growth area have been experimentally observed. Obtained results have been compared with the design and pre-lining data. Ten seepage tests using the inflow -outflow method and eight seepage tests using the ponding method were conducted to estimate seepage losses. Results indicate that almost all the parameters varied from the design values. A detailed comparison of the socioeconomic parameters has been carried out. Results from seepage tests show an approximately 78% reduction in losses.

Incorporating temperature into seepage loss estimates for a large unlined irrigation canal

Quantifying seepage losses from unlined irrigation canals is necessary to improve water use and conservation. The use of heat as a tracer is widely used in quantifying seepage rates across the sediment–water interface. In this study, field observations and two-dimensional numerical models were used to simulate seepage losses during the 2018 and 2019 irrigation season in the Truckee Canal system. Nineteen transects were instrumented with temperature probes and stage recording devices for inverse modeling to derive seepage flux and volumetric losses over the 39 km length of canal. The numerical models for each transect were calibrated and validated using the two-year dataset. Soil zones and observation data were used in each numerical model to help guide calibration of vertical and lateral heat and fluid fluxes. Model simulations were used to derive multivariable regression equations that consider stage, temperature, and hydraulic gradient. The results demonstrate the value of long-term datasets that illustrate the seasonality of groundwater levels, siltation, stage, and temperature on seepage rates. Seepage rates estimated by the numerical models range from 0.16 to 4.6 m3/d m−1. Total annual volumetric losses estimated for 2018 and 2019 were 1.6 × 10-2 to 1.2 × 10-2 km3, respectively. The seepage losses estimated by this study account for 32 % to 41 % of the inflow volumes. Regression models were able to reproduce seepage time-series simulated by the numerical models reasonably well. In arid environments, water diverted into irrigation canals may be influenced by seasonal variations in temperature sufficient to influence the water accounting of conveyed surface flows.

GEOGRAPHIC INFORMATION SYSTEM AND MODELING APPROACH FOR GROUNDWATER SYSTEMS OF RECHNA DOAB, PAKISTAN

Excessive groundwater pumping in Rechna Doab has caused a depletion of aquiferbody. Efforts were made to identify the ground flow dynamics and recharge sources of Rechna Doab.Finite difference model technique was used to study the groundwater system under steady state. VisualMODFLOW 2000 was used to steady state simulation of study area. Simulation of groundwater flowover an area of about 35,217 km2 with a uniform grid size of 2500m by 2500m was done. Study areawas divided into the grid of 138 rows and 100 columns. The seepage losses from canals, horizontalflows, recharge from precipitation and irrigation return flows were put to develop conceptual model.Discharge of canals, evapotranspiration and precipitation data was collected from local governmentagencies. Boundary conditions, hydraulic parameters and data of 50 observation wells were applied formodel calibration. The zone budget study under steady state simulation showed that the total directrecharge to the aquifer was 645.48 MCM and total drought of the aquifer was 645.49 MCM. Based onresults it was concluded that model was more sensitive to hydraulic conductivity and rechargeparameters.

Water Delivery Performance of Canal Irrigation: A Case Study of Chalakudy River Diversion Scheme

The role of irrigation is important in mitigating the challenges involved in food production under the changing climate scenarios. Adequacy and equity in water distribution are the primary concern regarding the performance of any irrigation scheme. Conveyance efficiency and two adequacy indicators, namely, Relative Water Supply and Adequacy were used to evaluate the performance of Chalakudy River Diversion Scheme (CRDS) located in central Kerala, India, in the present study, Water withdrawal data collected from Irrigation Department, and data collected from field measurements of canal discharge and seepage loss were used in the study. Irrigation requirement of the canal command area was worked out using the FAO’s CROPWAT 8.0 software. The results revealed that the average annual irrigation demand of the CRDS command area is 46.90 Mm3. Measured flow rate through the canal system showed that the flow decreases towards the tail end. Loss of water through seepage from the canal was high in the irrigation scheme due to the highly damaged condition of canal lining and poor maintenance. The CRDS canal system’s overall conveyance efficiency was found to be 51%. Based on Relative Water Supply and Adequacy Indicator, functioning of the irrigation scheme falls in the category of ‘fair’. Apart from proper repair and maintenance of canal system, conjunctive use of groundwater and canal water for irrigation is suggested towards the tail reaches to alleviate irrigation water inadequacy problems in the CRDS command area.

An introduction to Geosynthetic Cementitious Composite Mats and Barriers – a new approach to lining canals

A new class of geosynthetic has recently emerged known as GCCMs (Geosynthetic Cementitious Composite Mats) defined by the ASTM D-35 committee in 2017 as ‘a factoryassembled geosynthetic composite consisting of a cementitious layer contained within a layer or layers of geosynthetic materials that becomes hardened’. GCCMs consist of a three-dimensional fibre structure filled with a dry cement/concrete mix, overlain by a hydrophilic filter layer and underlain by a watertight membrane, which is typically a polymeric film. The material is delivered in its dry format and unrolled into place using similar installation techniques to traditional geosynthetics. Once in place, it is hydrated by spraying with water and the cement/concrete mix hardens. The result is a watertight polymeric film which is overlain by a protective fibre-reinforced concrete layer. GCCMs have been in use since 2009 and are predominantly used for the lining of water channels for small scale drainage. More recently a variant of GCCMs has emerged which integrates a geomembrane liner onto the rear surface which allows the joints to be thermally welded. These are known as Geosynthetic Cementitious Composite Barriers (GCCBs). It is estimated that Egypt has more than 110,000 kilometers of canals comprised of approximately 30,000 km of public canals (first and second level) and 80,000 km of private third-level canals (mesqas) and irrigation ditches. A common problem associated with canals, is seepage. Seepage can result directly in water loss through the network or result in waterlogging of adjacent land. In the case of land used for cultivation, waterlogging can reduce crop yields or cause salinization of the soils. This does not only occur in earthen canals, but also in concrete lined canals, particularly those that have experienced cracking, scour, panel separation or damage. It is also a common misconception that concrete lining of canals is an effective method of mitigating seepage losses. The 25-year study performed by the USBR indicates that concrete over geomembrane has a 95% effectiveness at reducing seepage through canals1. This abstract introduces a revolutionary new class of materials called Geosynthetic Cementitious Composite Mats (GCCM’s), specifically Type II GCCM’s to ASTM D8364 for lining of bulk water transportation canals. The Type II GCCM in question consists of concrete encapsulated by between two geotextile layers with a minimum 1mm thick LLDPE geomembrane backing which can be thermally welded to produce a testable and low permeability joint, per ASTM D5820, with air channel testing to ensure a leak free installation. Because it is a composite of concrete and geomembrane in a single application, installation can occur as a one-stepprocess imparting both cost and time savings to the project. The abrasion resistance of the concrete layer is 3.5 times that of typical 20Mpa concrete typically used for canal applications. With a design life of more than 50 years, this new product classification will provide a feasible, long-term solution to help preserve and protect fresh, clean water, one of Egypt’s most precious – and ever more scarce – natural resources.

How GCLs can help create more efficient waterways?

Commercial, agricultural, and recreational canals continue to be important economic drivers in many countries. A wide range of geosynthetic products, such as geotextiles, geomembranes, and geosynthetic clay liners (GCL), help create more efficient waterways. Barrier geosynthetics such as GCLs are used to improve canal performance in numerous applications. For example, for irrigation canals, geosynthetic lining systems prevent seepage loss into soils. This improves the economics and sustainability of the irrigation system. The geosynthetic barrier also optimizes water flow in the canal network. Irrigation is conveyed more quickly and efficiently. This presentation reviews the application of GCLs in hydraulic structures including canals, and presents considerations for GCLs to perform as an impervious lining in these applications.

Static and pseudo-static stability analysis of right earthen embankment of nagarjuna sagar dam by geostudio

To ensure the safety of the dam, stability assessment of the dam is necessary. The objective is to perform slope stability analysis for upstream, downstream and seepage analysis during steady state, transient seepage conditions and to know about the displacement occurred at history nodes by the application of pseudo-static ground motion. The present work deals with the behavior of the Right earthen embankment of Nagarjuna Sagar which is in earthquake prone area of Zone-II (as per IS 1893-2002). Stability parameters slope, seepage and earthquake analyzed by SLOPE/W, SEEP/W, QUAKE/W tools in GeoStudio 2022 (finite element modeling based software). The model with full reservoir level is first analyzed by SEEP/W to find piezometric line which is basis to perform SLOPE/W for finding slope stability. Later an earthquake motion of 0.1 peak ground acceleration is subjected to it by using QUAKE/W. It is concluded from results, that obtained factor of safety lie within safety limits and seepage loss observed during the design life of 100 years is 562290 m3, 3431117 m3 for steady state and rapid drawdown.

Social and Institutional Factors Influencing the Performance of Tank Irrigation System – A Study of Uthiramerur Tank in the Indian State of Tamil Nadu

Aim: Tanks were the major sources of irrigation for agriculture and storehouses of economic, social, aesthetic and environmental use values. However, in the present context, the current trends are showing that area and number of tanks are being reduced due to poor maintenance, encroachments, degradation of catchment area and siltation, etc. This calls for rehabilitation and rejuvenation of the existing tank irrigation systems so as to preserve this precious natural resource for the livelihood of future generations ahead. Hence this present study was undertaken to identify the social and institutional factors influencing the performance of tank systems in Kanchipuram district in the Indian state of Tamil Nadu.
 Study Design: Quota and Multistage random sampling method was followed.
 Place and Duration of Study: Command and Non-command areas of the Uthiramerur Tank in Kanchipuram district of Tamil Nadu during 2020-2021.
 Methodology: A Sample size of 120 sample respondents from the different locations of the command areas (Head, Middle, Tail and Non-command area) of Uthiramerur tank were selected and interviewed.
 Results: It was observed from the performance analysis that over the years the tank’s performance was decreasing both in terms of filled in capacity vis-à-vis rainfall received (Above the tank outlet) and in terms of actual gross area irrigated vis-à-vis its potential command area (Below the tank outlet) . One of the important reasons for the decline in the performance of Uthiramerur tank was attributed mainly to institutional deficiencies wherein concrete action lacked thereof.
 Conclusion: The study suggested the following actions for the improvement of tank’s performance- streamlining the feeding channels of the tank by removing the encroachments, lining of channels to minimize the seepage losses and ensuring better water distribution, periodic desiltation ,strengthening the revenue collection mechanisms, encouraging the conjunctive water use and rejuvenating the water user association.

Improving Resource Utilization Efficiency and Productivity in Rice-wheat Cropping System through Cutting Edge Technologies: An Overview

Rice-wheat cropping system is one of the major cropping system practiced in South Asia on 13.5 m hectares area, 10.3 million hectares of which are in the Indo-Gangetic Plains (IGP). The Indian Rice-Wheat Cropping System (RWCS) accounts for more than 70% of the country’s total grain production which is essential for ensuring national food security. Widely used RCT known as Zero Tillage (ZT) in which wheat is directly sown into the undisturbed soil after rice harvested. The Adoption of Furrow Irrigated Raised Bed System (FIRBS) in wheat production saves 30-40% water, seed use by 25-30% and nutrients use by 25% without reducing yield. The RCTs involve residue management (mainly residue retention), crop diversification and no- or minimum tillage with direct seeding and bed planting. AWD in rice save water by 10 to 30% while reducing seepage and deep drainage losses and Brown manuring is highly beneficial for weed control, water and soil conservation and nutrient supplementation. The cultivation of aerobic rice is a new system of growing in non-flooded, non-puddled soils, with high external inputs using innovative technique of aerobic rice that require less water than transplanted rice. A simple and inexpensive diagnostic tool leaf colour chart can be used for monitoring the relative greenness as a measure of the plant N status. Thus, it can be concluded that RCT adoption improving soil health, water use efficiency and nutrient use efficiency with higher sustained yields which leads to sustainable improvements in RWCS. By saving on labour, time, diesel, fertilisers, pesticides, and farm power, resource conservation technologies lower the cost of farming and also lessen environmental pollution.

GENERATING RATING CURVE AND RATING TABLE OF GOLARCHI MINOR

Hydrologists must have huge theoretical and practical knowledge of irrigation networks such as rivers, canals, streams, channels, and minors. Because whole irrigation system relies on a gauge and discharges relationship which is essential for controlling floods, water resource management, and hydrologic modeling. The true and consistent figures of flow rate in the irrigation system are important for irrigation water efficiency. Mostly, Hydrologic modeling activities like hydraulic structures, designs, and management of surplus water in canals are subjected to the flow of irrigation water which is derived from the rating curve (RC). The managing of irrigation water in the system must be essential for crop water requirements and estimation of seepage losses. Thus, to fulfill the objectives, field activities (discharge measurement) were conducted in Golarchi minor of the Left-bank area water board. The main target was to calculate real discharge at different gauge levels and to develop a rating curve and rating table for the accurate distribution of irrigation water in the command area. Hence, the discharge was measured with a current meter and the area velocity method was employed for flowing water. The discharge was taken at three different gauges i.e., 1.2ft, 1.34ft, and 1.55ft with the discharge of 51.921cusecs, 55.021cusecs, and 58.197cusecs. Then collected data was exported to MS Excel for manipulation and for developing rating curves. The power equation was developed for Golarchi minor for confirming the different discharges on different gauge heights. The results of the study calculated as 1.1ft gauge to 1.7ft gave discharge 50.383cusecs to 61.009cusecs. It is concluded that the present study suggested that there should have an automatic gauging station to know the real demand for irrigation water in the command area and di-siltation should be done.

WATER MANAGEMENT IN GHATERA BABAJI MINOR IRRIGATION PROJECT, MADHYA PRADESH, INDIA

Water is a vital component of nature, which brings life in land; therefore the judicious utilization of water is needed for all types of human advancement. India is a monsoon dependent country for its water resources. Irrigation sector has been fundamental to India’s economic development and poverty alleviation, since 25% of India’s Gross Domestic Product (GDP) and 65% of employment are based on agriculture (MOWR GOI, 2006). The world’s total irrigated area was 249.5 M ha in 2011 in which India has 21.7% share in irrigated area in the world. The global consumption of water in agriculture is around 71% of the total water use (FAO, 2008). Considering the importance of irrigation management and the water user’s participation in increasing water productivity and the development of existing irrigation command area, this study was carried out to assess the present irrigation system of command area and to perform diagnostic study for the possible improvement in command area of Ghatera Babaji tank canal situated in Betwa River basin. The study area has a gross command area of 147 ha out of which cultivable area are 127 ha. Irrigation is supplied during Rabi season in about 121 ha. Main canal is 1360 m long with a slope of 1 in 1000. The command area has 101 land holdings ranging from 0.23 ha to 6.32 ha belonging to 87 farmers. Majority of farmers have small and marginal holdings (up to 2 ha), middle age (> 39 yrs) and with low income (< Rs 50,000 per annum) and have education up to primary or middle school level. The basic infiltration rate varies from 0.2 cm/hr to 2.4 cm/hr. The major crop of the area is Wheat followed by small area under Gram and Vegetable during Rabi, whereas, Soybean is grown during Kharif season. Discharge measured in main canal varies from 0.066 m3 /sec at head reach to 0.013 m3 /sec at tail reach. Discharge reaching to farmer’s field is changing from 3.82 to 5.36 lps. Seepage losses in main canal are measured to be 38.83 m3 / Mm2 to 16.04 m3 / Mm2 wetted area. Overall irrigation efficiency is computed to be 35 per cent. Productivity of Wheat crop varies from 4.5 to 35.1 q/ha which when converted to water productivity ranges from 0.33 to 1.55 kg/m3 . Water productivity for Gram varies from 0.97 kg/m3 to 1.86 kg/m3.

A systematic approach for estimating water losses in irrigation canals

In order to determine water losses in irrigation canals, a systematic approach was developed, consisting of two main components: a seepage simulation model and a hydraulic simulation model. The SEEP/W module of the Geo-Studio software was used to simulate the seepage rate, and the Hydrologic Engineering Center-River Analysis System (HEC-RAS) hydrodynamic model was used for hydraulic simulation. Different operation scenarios were designed to investigate all possible situations in daily operation of water distribution and delivery systems. The seepage simulation results show that the seepage losses were higher at the bottom and corners of the canal, because the hydraulic gradient was affected by the hydraulic load. The hydraulic simulation results show that due to physical and management infrastructure (using non-automated and operator-based regulation structures), operational losses accounted for a significant volume of losses compared to seepage losses. In most operation scenarios, the maximum seepage loss was 10%, and the remaining 90% was related to operational losses. It is concluded that any factor (decrease or increase of inflow to the canal) that causes an increase or decrease of operational losses is ultimately a determining factor in reducing or increasing total losses. Therefore, management approaches should be adopted to improve performance of the system and reduce losses, especially operational losses, by improving the operation methods of water level regulation and off-take structures.