Abstract
This study aimed to ascertain water allocation for different purpose in Tiga dam located at Hadeja Jama’are River Basin (HJRB) using WEAP model, in order to resolve the conflict between the requirements (water allocation) of Kano city and major irrigation project. The research commenced with a preliminary site investigation through reconnaissance survey to analyze hydraulic nature, agricultural activities, other activities related to water resources in the basin and collection of metrological and hydrological data. 31 years metrological and hydrological data, population and growth rate, irrigation area and number of industries from 1987 to 2017 were used in the WEAP model software. The model predict that in from 2018 to 2050 the dam will not be able to meet up with the total demand, it is only capable of supplying annual average of 9040 Million Cubic Meter (MCM) for agriculture with unmet demand of 2757 MCM, 328 MCM for Kano city with unmet demand of 7.8 MCM, 1.0 MCM for industries with unmet demand of 0.3 MCM and generate annual average of 28000 Gj hydropower with unmet power demand of 8.6 Gj. In general, this model predicts that the annual average future water supply from 2018 to 2050 for all the purposes is 9361 MCM with unmet demand of 2765.1 MCM. The dam can supply 77.09% of the major irrigation project demand, 79.92% of the Kano industries demand, and 97.68% of the Kano city water demand in future. With the use of WEAP model software, we can confirm that the water scarcity and difficulties will arise in Kano state Nigeria as long as but creations of means for wastewater re-use and recycling, controlling rapid population growth and unnecessary water use for irrigation may help seriously in reducing unmet water demand.

Key words: WEAP Model, Water Allocation, Unmet Demand, Water supply, Tiga Dam, Kano City, Agricultural Demand and Industrial demand.