SIMULATION STUDY OF IRRIGATION IN UPPER BETWA BASIN

Abstract

elp to assess the present situation and assist in the development and evaluation of solutions may be important. Decision support systems have been developed since the 1970s to help tackle semi-structured and unstructured decision problems. Decision support systems (DSSs) are increasingly being used in water management for the evaluation of impacts of policy measures under different scenarios. One of the DSS instrument is RIBASIM 7.0 (River Basin Simulation Model) which is designed to simulate water development and management policies in river basins and analyzing the behavior of river basins under various hydrological conditions. RIBASIM 7.0 has been used as a DSS instrument in planning of upper Betwa basin. Water resource development in Betwa basin has focus on irrigation and hydropower. A large number of medium and minor irrigation project have been developed. In addition there are major multipurpose projects. RIBASIM 7.0 has been used as a DSS instrument for analysis of water balance of a basin to be simulated. The resulting water balance provides the basic information on the available quantity of water as well as the composition of the flow at every location and any time in the river basin. The Betwa river (earlier known as Betravati River) originates from Barkhera in Raisen district of Madhya Pradesh state in India. Betwa river is a southern tributary of Yamuna river which in turn is a tributary of Ganga river. There are several problems in Betwa Basin, the region, though historically important, continues to be highly underdeveloped due to lack of irrigation facilities, the cultivators cannot provide even tube-wells, shallow wells or tanks through their own resources, the rainfall is also scanty, uncertain and unevenly distributed, land degradation has taken place and may further increase due to continuing deforestation. Betwa basin is spread over the parts of states of Madhya Pradesh and Uttar Pradesh.. Any development in this area may take place properly if there is proper cooperation between the two states. HYMOS 4.0 software uses Sacramento model to synthesize discharge data and has been used to synthesize monthly flow series for thirteen years in each of the twelve tributaries sub-catchments of Betwa basin up to Rajghat. The HYMOS 4.0 software has been used to generate hydrological data that is needed as data input to RIBASIM 7.0 software. The result of Q Observation — Q Simulation correlation, compare sum of 6 tributaries discharge with observed discharge at Basoda, the R2 = 0.862 and the result of Q Observation — Q Simulation correlation, compare sum of 12 tributaries discharge with observed discharge at Rajghat, the R2 = 0.841. DSS-RIBASIM is one of the Decision Support System software in the process of water resource planning in river basin. River basin planning is a very complex planning process spatially and temporally, and many of social and economic aspects in improving food production and supply of raw water. There are four cases or scenarios that have been applied in upper Betwa basin. The aim of the scenarios are to make a projection of water balance and water needed estimation if there are increasing in water demand and change in cropping pattern until year 2030. Basic scenario shows that Betwa basin has the total water resources potential discharge 7794.92 MCM equivalent to average annual discharge of 247.17 m3/s. Result of the Scenarios show irrigation water needs for year 2010 (Scenario 1) = 25.433 m3/s, in year-2020 (Scenario 2) = 25.175 m3/s, and in year 2030 (Scenario 3) = 24.931 m3/s. DMI water needs for year 2010 (Scenario 1) = 24.817 m3/s, and year 2020 (Scenario 2) = 32.586 m3/s, year 2030 (Scenario 3) = 42.916 m3/s. There is no deficit in irrigation water needs due to water availability at the reservoir of each irrigation project. Deficit of water needs happen at DMI water supply as the following, in. year 2010 (Scenario 1) = 6.363 m3/s or 26.02% of DMI water needs in yr. 2010, in year 2020 (Scenario 2) = 9.830 m3/s or 30.62% of DMI water needs in yr. 2020, and year 2030 (Scenario 3) = 14.849 m3/s or 35.12% of DMI water needs in yr. 2030. DMI water needs are still need to be fulfilled from other water source, for example groundwater source. Comparison of water resources utilization (for Irrigation and DMI) with total water resources potential in upper Betwa basin for year 2010 (Scenario 1) = 17.74% utilization, in year 2020 ..