Effect of Watercourse Lining on Water Distribution (Warabandi) in the Command Area of Laiqpur Ex Ali Bahar Minor, District Sujawal, Sindh, Pakistan

Many large irrigation projects in Nepal operate under command area development works that emphasize on-farm water distribution and management. These projects have specific design characteristics that were planned to comply with available water resources, climatic conditions, soil type, and water distribution technology. The water distribution technologies differ based on the design needs of each individual project and the design preferences of various foreign consulting firms. This article focuses on the issues of planning and designing water distribution systems of large irrigation systems at the irrigation service delivery level. The layout planning of an irrigation system is an important aspect of design for water distribution, typically guided by hierarchical system. This article also highlights the existing canal hierarchy of these systems and their appropriateness for efficient water distribution. Furthermore, the appropriateness of the structured system is also examined in the Sunsari Morang Irrigation Project. The article concluded with some suggestions for planning and designing command area development works of forthcoming large irrigation projects such as the Sikta Irrigation Project, the Babai Irrigation Project, and the Mahakali Irrigation Project Stage-III.HYDRO Nepal JournalJournal of Water, Energy and EnvironmentIssue: 19Page: 25-30

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Modernization of the left bank irrigation system of the Kaudulla reservoir of Sri Lanka

Journal of Water and Climate Change ◽

10.2166/wcc.2021.122 ◽

2021 ◽

Author(s):

W. D. M. Wijenayaka ◽

S. B. Weerakoon ◽

Farncis Mutua

Keyword(s):

Sri Lanka ◽

Irrigation Water ◽

Water Distribution ◽

Irrigation System ◽

Command Area ◽

Left Bank ◽

The North ◽

North Central Province ◽

Total Capacity ◽

Paddy Cultivation

Abstract Irrigation water management in the paddy cultivation area under the left bank canal of the Kaudulla reservoir (Kaudulla tank) in the North Central Province of Sri Lanka has become a serious issue due to limited water availability and inefficient water distribution infrastructure at present. Insufficient storage capacities of the village tanks in the cultivation area, low rainfall during some months and regulated inflow from the transbasin diversion to Kaudulla tank have had a significant impact on yield in the two cultivation seasons of the year. In this article, modernization of irrigation infrastructure in the command area was investigated for effective utilization of limited available water. The results of the calibrated and validated HEC-HMS model and CROPWAT model were used with WEAP to evaluate the water balance and demand to identify the best investment for improving irrigation water supply to maximize the return. Economic analysis was carried out using the net present values for different modernization options. Accordingly, the construction of a new canal system and augmentation of the capacities of village tanks from the present total capacity of 3.8–20 MCM was found to be the most appropriate option. This intervention will increase the income from yield by 205 million with a payback period of 12 years in the Yala season.

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Impact of Lined Canal on Shallow Tubewell Irrigation and Their Acceptability by the Farmers

The Agriculturists ◽

10.3329/agric.v12i2.21740 ◽

2015 ◽

Vol 12 (2) ◽

pp. 116-125

Author(s):

Abu Sayed ◽

A F M Saleh ◽

Md. Altaf Hossain ◽

Zobayer Ali Basunia ◽

Md. Afzal Hosain

Keyword(s):

Water Distribution ◽

Irrigation System ◽

Group Discussion ◽

Water Saving ◽

Command Area ◽

Irrigation Time ◽

Benefit Cost ◽

The Impact ◽

Area Development ◽

Conveyance Losses

The comparative conveyance losses between lined and unlined canals, impact of water saving on command area development and irrigation cost, and farmers acceptability of lined canal in shallow tubewell (STW) irrigation schemes were studied during 2010-11 Boro season at three upazilas: Manikgonj Sadar of Manikgonj district, Dhamrai of Dhaka district and Mithapukur of Rangpur district. The conveyance loss was measured using inflow-outflow method and focus group discussion (FGD) was carried out with the pump owners and farmers to assess the impact of water saving on command area development and the acceptability of lined canal technology. Average conveyance losses were found to be 41, 48 and 45% in the existing earthen canals; 18, 21 and 24% in improved earthen canals; and 12, 11 and 13% in pre-cast canals at Mithapukur (M1), Manikgonj Sadar (M2) and Dhamrai (D) schemes, respectively. The water saving did not increase the command area in any of the schemes but reduced the irrigation time and saved fuel requirement for irrigation. On an average, 32, 23 and 30% fuel were saved by improved earthen canals where as 45, 46 and 48% were saved by pre-cast canals for M1, M2 and D schemes compared to earthen canal. The benefit-cost ratios of improved earthen canals were 1.36, 1.38 and 1.30 where as 3.36, 4.28 and 3.34 by pre-cast canals for M1, M2 and D schemes, respectively. The internal rate of return (IRR) from the investment on water distribution was over 50%. The lining technology was acceptable to pump owners, but did not impress the farmers who share the crop with the pump owners as price of irrigation or pay on the basis of irrigated area. In order to make the technology acceptable to the farmers, polices must be framed to share the benefits of lining by the pump owners with the farmers by reducing the price of irrigation water or through financial support of GO and NGOs for efficient use of STW irrigation system in Bangladesh.The Agriculturists 2014; 12(2) 116-125

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Challenges in calibration of water distribution network: a case study of Ramnagar Elevated Service Reservoir command area in Nagpur City, India

Water Science & Technology Water Supply ◽

10.2166/ws.2020.047 ◽

2020 ◽

Vol 20 (4) ◽

pp. 1294-1312

Author(s):

Shweta Rathi ◽

Rajesh Gupta ◽

Pawan Labhasetwar ◽

Pranav Nagarnaik

Keyword(s):

Water Distribution ◽

Water Distribution Network ◽

Command Area ◽

Uncertain Parameters ◽

Precise Data ◽

Water Demands ◽

Important Input ◽

Zone Ii ◽

Pipe Roughness

Abstract Calibration of a hydraulic model is a challenging task as it considers the involvement of a large number of uncertain parameters. There are some parameters like length and diameter of pipes, for which fairly accurate values can be obtained. As with all hydraulic models, water demands are one of the main parameters that cause the most uncertainty in the model outputs. The calibration of the water demands is usually not feasible, which is attributable to the limited quantity of available measurements in most real water networks. However, some parameters like nodal demands and pipe roughness coefficients are estimated close to the actual values. Various types of valves are used for flow control by throttling. Hence, their setting in the field is also an important input to the model. Having more precise data helps in reducing time and results in better calibration as presented in the case study of one hydraulic zone served from Ramnagar Elevated Service Reservoir (ESR) (Zone II) in Nagpur City, Maharashtra State, India. This paper aims at presenting the complexities and challenges involved in calibration of the study area. It further describes the entire process from collection of the required data to the calibration of the network.

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Rehabilitation of operation regimes in aged irrigation schemes based on hydraulic simulation

Water Science & Technology Water Supply ◽

10.2166/ws.2022.004 ◽

2022 ◽

Author(s):

Hasan Bakhoda Bishehgahi ◽

Atefeh Parvaresh Rizi ◽

Amir Mohammadi

Keyword(s):

Water Distribution ◽

Water Productivity ◽

Real Data ◽

Command Area ◽

Irrigation Season ◽

Irrigation Scheme ◽

Hydraulic Simulation ◽

Water Users ◽

Level Of Satisfaction ◽

A Subunit

Abstract The selection and employment of proper methods in water distribution causes increasing in water productivity and the level of satisfaction of water users. It is faced with more difficulties in aged irrigation projects due to temporal changes such as changes in the crop patterns, development of the command area and destruction of canals and hydraulic structures. The plan of operation methods have some hydraulic and social complexities and therefore is usually simplified or implemented experimentally. This research investigates the best options for water distribution to the paddy fields in a subunit of Sefidroud irrigation scheme based on field survey, recording real data and hydraulic simulation with employing SOBEK hydrodynamic model. Different operation scenarios were defined and then simulated in the current physical state of the scheme through replacing the exhausted intake structures with sluice gates. Finally, the better operation scenarios during the irrigation season were suggested based on the distribution indices. The results show that in spite of the current situation, water loss could reach the minimum by employing modification scenarios and indices of adequacy and equity of water distribution improve.

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