Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Study on the Irrigation Water Distribution System Developed by BARInd Multipurpose Development Authority

Md. Mosiur Rahman
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET)

A.H.M. Kamal
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET)

Abdullah Al Mamun
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET)

Dr. Md. Shafi Uddin Miah
Department of Civil Engineering, Rajshahi University of Engineering & Technology (RUET)

Abstract/ Executive Summary:

Irrigated agriculture has been playing a vital role for the growth in crop production in Bangladesh. Minor irrigation comprising of shallow tubewells (STWs), deep tubewells (DTWs), hand tubewells (HTWs) and low-lift pumps (LLPs) is a major irrigation system in the country. Poor performance of irrigation is an issue for the expansion of irrigated area. The present study was carried out to examine the conveyance efficiency and rate of irrigation water loss in DTW schemes in Bogra, Thakurgaon and Godagari zones of Barind Management Development Authority. There were various types of water distribution identified in these schemes with including Poly Venyl Chloride (PVC) buried pipe, cement concrete (CC) rectangular, Ferro trapezoidal, Ferro semicircular and rectangular earth drain. The average conveyance efficiency of PVC buried pipe for Bogra, Thakurgaon and Godagari zones ranged from 94.46% to 95.37% and rate of water loss ranged from 5.45% to 9.55% in three study zones. Average conveyance efficiency of CC rectangular for Bogra and Godagari zone ranged from 91.20% and rate of water loss from 6.58% to 9.93%. Average conveyance efficiency of Ferro trapezoid for Bogra and Godagari zone ranged from 87.80% to 90.06% and rate of water loss ranged from 9.94% to 12.21%. Average conveyance efficiency of Ferro semicircle for Bogra and Godagari zone ranged between 88.13% and 86.82% and rate of water loss between 11.59% and 11.68%. Average conveyance efficiency and rate of water loss of rectangular earth drain Godagari zone was 58.66% and 42.29% respectively. About 80% farmers recommended buried pipe irrigation system and about 20% semi-circular channel. The study suggests that the improved water distribution system as developed by BMDA is sustainable to increase productivity of irrigation systems in Bangladesh.

Keywords: Irrigation scheme, Distribution system, Conveyance efficiency, Performance evaluation.

Location:

Start Date:

End Date:

Program Area: Crop-Soil-Water Management

Commodity: Water management

Objectives:

The present study evaluates performance of irrigation water distribution system developed by BMDA in the northwest region of Bangladesh.

Methodology:

BMDA develops low cost channel for the improvement water distribution system since 1980. The channels are better than traditional earthen channel especially in respect of efficiency and cost. Different types of channel with various materials have been tried in the farmer's field for improvement in water distribution system including better management of irrigation. The operational cost of traditional earthen channel has become a burden to the farmers unless the command area is large. The conveyance efficiency of traditional earthen channel is 50-55% and water loss rate 40-45% (BARI, 20007).a. Lined open channel There are several methods of measuring flow in open irrigation channels on the farm. They can be grouped into four categories: (i) volumetric measurement, (ii) velocity-area method, (iii) measuring structures (orifices, weirs, flumes), and (iv) Tracer methods (dilution). In eight water distribution schemes volume of water (inflow and outflow) was measured by the velocity area method. The rate of flow passing a point in an open channel was measured by multiplying the cross-sectional area of the flow section at right angles to the direction of flow by the average velocity of water. Discharge = Area * Velocity. b. Buried pipe The pump discharge from pipe was measured using Trajectory method. In this method the rate of flow is obtained by coordinate determination of any point of flow (Moniruzzaman, 1999). In operating condition the flow, at the outlet of pipe of the pump should be full flowing condition. The outlet of the pump may be horizontal or angular. For horizontal pipe, “L-scale” was used to measure the flow rate of the outlet pipe of pump in which small arm was 4 inch or 6 inch and long arm may be any value as required. The horizontal and vertical distances are called the "X" and "Y" coordinates, respectively. To get the values of "X" and "Y" the long arm of L-scale was set horizontally above the pipe so as the small arm of the L-scale touch vertically just above the jet. The value of "Y" was constant as 4 inch. The inside diameter "D" of the pipe was also measured. DETERMINATION OF THE LOSSES OF IRRIGATION WATER The conveyance loss was measured using the inflow-outflow method, which involves measurement of the rate at which water flows in to a water course test section and the rate at which water flows out of it. a. Lined open channel Conveyance losses in the lined open channels were measured using velocity-area method. The reading was taken when the flow became steady. Readings were recorded simultaneously three times at 5 minutes interval. By measuring the section length under test the loss of water per 100 m was calculated by the following formula (Michael, 1986) Ql = (Qi – Qo)/L*100 (3) Where, Ql = water loss rate in buried pipes (l/s/100 m) Qo = quantity of water delivered by a conveyance system (outlet) (l/s) Qi = quantity of water delivered to a conveyance system (inflow) (l/s) L = length of pipeline under test (m) b. Buried pipe To measure the water loss in buried pipes distribution, pump discharge was measured by trajectory method. This method was repeated three times to get an average discharge of the pump. The discharge at an outlet near the end of the main line was measured by velocity-area method. Measurements were taken simultaneously when the flow through the channel became steady. The water loss was calculated using the formula (3).DATA ANALYSIS A. EFFECT OF IMPROVED WATER DISTRIBUTION SYSTEM The changes in respect of command area, land for distribution system, irrigation cost, uniformity in distribution of irrigation water, time-span reaching the irrigation etc. are described in this section. Most of the data were collected through interview with the relevant farmers as well as managers and field observation. By using scheme map, the actual and potential command area, location of channel system and land use planning were also identified.

Source of Information: Journal of the Bangladesh Association of Young Researchers (JBAYR): Volume 1, Number 2, June 2011, Page: 63-71, ISSN 1991-0746 (Print)

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

All the farmers and water user beneficiaries’ views were positive in improved distribution system especially of buried pipe system. According to them, development of this lining technology is very appropriate in Bangladesh context and also in developing countries. More than 70% of the farmers and water user beneficiary opined that channel of every DTW schemes could be constructed buried pipe system. The conveyance efficiency of PVC buried pipe for Bogra, Thakurgaon and Godagari zone were 95.37%, 90.46% and 94.46% and rate of water loss were 6.11%, 9.55% and 5.45% respectively. BMDA developed water distribution systems are more effective, efficient and far better than the conventional system and developed water distribution systems at different locations in the country are running in good condition without any major constraint. This system could be widely adopted as a model in the field for increasing agricultural production in Bangladesh. Among all the water distribution systems, the PVC Buried pipe line system is the most suitable among all distribution systems.

Knowledge Management: Journal