Spatial and temporal climatic variability influence on the productivity of agricultural watershed and irrigation systems. In a large irrigation system, the quantification and regulation of the flow at different locations of the channel is quite difficult manually, leading to a poor delivery of supply and demand. Water shortage is a crucial issue due to mismatch between available water and demand at intake point of Tanjung-Karang Irrigation Scheme. This study assessed the potential impacts of climate change on basin outflow for 2010–2039, 2040–2069, and 2070–2099 to the baseline period (1976–2005) and used it as input hydrograph to simulate river discharge. A Hydrologic Engineering Corps Hydrologic Modeling System (HEC-HMS) model driven by projections from ten global climate models (GCMs) with three scenarios (Representative Concentration Pathways (RCPs) 4.5, 6.0, and 8.5) used to simulate the outflow and the Hydrologic Engineering Centers River Analysis System (HEC-RAS) model applied for hydraulic modeling. The projected seasonal streamflow showed a decreasing trend for future periods. The average available irrigation supply for historical period is 15.97 m3/s, which would decrease by 12%, 18%, and 21% under RCPs 4.5, 6.0, and 8.5, respectively. Projected irrigation supply showed oversupply and undersupply to the required supply during the growing season. Simulated discharge could therefore be incorporated into cropping practices to boost the sustainable distribution of water under the new realities of climate change in the future.

Agro-hydrological water management frameworks help to integrate expected planned management and expedite regulation of water allocation for agricultural production. Low production is not only due to the variability of available water during crop growing seasons, but also poor water management decisions. The Tanjung Karang Rice Irrigation Scheme in Malaysia has yet to model agro-hydrological systems for effective water distribution under climate change impacts. A climate-smart agro-hydrological model was developed using Excel-based Visual Basic for Applications (VBA) for adaptive irrigation and wise water resource management towards water security under new climate change realities. Daily climate variables for baseline (1976–2005) and future (2010–2099) periods were extracted from 10 global climate models (GCMs) under three Representative Concentration Pathway scenarios (RCP4.5, RCP6.0, and RCP8.5). The projected available water for supply to the scheme would noticeably decrease during the dry season. The water demand in the scheme will differ greatly during the months in future dry seasons, and the increase in effective rainfall during the wet season will compensate for the high dry season water demand. No irrigation will therefore be needed in the months of May and June. In order to improve water distribution, simulated flows from the model could be incorporated with appropriate cropping patterns.

Traditionally project success has been defined in terms of the time, cost and quality. Extending the traditional triangle to include other factor of stakeholders and end-user provide a more complete view of project success. The aim of the study is to determine the factors that can be used to assess water reservoir project success. The factors for project success in from previous study have been identified and then, narrowly to determine the critical success factors by evaluating the appropriateness of the factors. Delphi method has been applied and a one day seminar has been conducted with a group of expert who involved in construction of water reservoir project in a water company agency. An initial questionnaire has been asked during the seminar through brainstorming and discussion session to identify potential success factors. Following from the seminar, a questionnaire survey was distributed to the participant for the purpose to establish the level of important of the factors. From the feedback of thirty (30) expert opinion and fourteen (14) returned expert surveys, refined seven (7) clusters of project success factors were identified: Clear Realistic Objectives; Quality Factor; Time Factor; Cost Factor; Deliverable; Legacy System; and Safety, Health and Environment. A template for measuring project success has been produced base on Priority Evaluation Method. At the end, five (5) actual projects in the water company agency have been used to show the application of the measuring project success template specifically for the water reservoir project. It has been used to determine the successfulness of each project. It shows that the main factor of an unsuccessful water reservoir project in this case are because of unclear realistic objectives, deliverable issue and time factor.