J. Basic. Appl. Sci. Res., 3(3)420-425, 2013 © 2013, TextRoad Publication ISSN 2090-4304 Journal of Basic and Applied Scientific Research www.textroad.com *Corresponding Author:Joni Hermana, Department of Environmental Engineering, Faculty of Civil Engineering and Planning, Institut Teknologi Sepuluh Nopember, Surabaya. Email: Hermana@its.ac.id Environmental Impact Assessment of Land Use Due to the Change of Water Resources Potentialin Urban Watershed: A Review Fransz Semuel Siahaya 1 , Joni Hermana 2,* 1 Department of Civil Engineering, State Polytechnic of Ambon, Doctoral Program in Environmental Engineering, Institut Teknologi Sepuluh Nopember, Surabaya 2 Department of Environmental Engineering, Faculty of Civil Engineering and Planning, Institut Teknologi Sepuluh Nopember, Surabaya ABSTRACT Problems of water resources are becoming of a major concern today, it is because there is an imbalance between the potential of water availability to the water needs of the population. The main cause is due to the fast growing population that is reflected in the increased activities of land-use change from forest to agriculture and settlements. This rapid land use change pattern caused a disturbance on the environmental conditions of its watershed (DAS). Erosion and flooding problems are the common results of land use activities that do not fit with the criteria of land suitability. Thus, a comprehensive study is needed to compare impacts that are caused by the land use change activities through a review of several studies. The results of this review showed that all the upstream catchment areas have the same problem, namely un controlled land use result caused by the pull- up and driven factors, each are reflected in the water resources availability and in adaptation activities of its society, respectively. Keywords: Environmental Impact Assessment, LandUse Change, Water Resources Potential INTRODUCTION One of the main problems in sustaining the potential of water availability is the land use changes that lead to the expansion of the settlement area, thus causing an imbalance in the soil water storage [1]. It is further described [2], who explained that the change in land use will have an impact on global climate change that directly results in a decrease in the precipitation percentage and an increase in the potential evapotranspiration. The direct impact of climate change that causing an imbalance of rainfall distribution and its intensity, is the disturbance of hydrological cycle, which in turn affects the quality and quantity of water resources in the watershed area (DAS) [3]. Disruption of the hydrological cycle processes according to [4], is related to the location of the watershed that is situated in urban areas, or that is dominated by agricultural and settlement activities, which resulted in a negative impact on the function and the role of the basin as a source of water providers and distributors, namely inequity of water balance. A condition on the water balance of the watershed area is an important indicator to show the environment quality. This is related to population pressure, which is reflected by the pattern of land use that is uncontrolled in the catchment area, therefore it affects the hydrological runoff in the basin's segment [5]. The pressure of population is caused by many factors [6], such as: a) land conversion from forest to agriculture and settlement, b) pollution by domestic and industrial wastes, and c) exploitation of ground water that is not under control. Furthermore, the environmental management of watershed area should be measured by using a systematic and an integrated approach. It means that a proper analysis and exact model are required to solve the problem of the watershed environment [7,8,9]. One example of negative impacts from an uncontrolled land use patterns is a growing runoff, which can lead to an erosion and landslides in areas with the slope of greater than 30%. The more limited ability of the soil infiltration due to the impermeable layers that block the entry of water, the less the ground water volume reserve that leads to the increase in the potential of flooding [10]. The problem of environmental degradation due to the uncontrolled land use change is occurred in all over watershed areas, especially upstream, which systematically affects the river system as a whole. Thus, this paper will compare some of the impacts caused by the change of the land use upon the potential availability of water, which occurs in some watershed areas, particularly at Galala watershed, in Ambon, North Moluccas. 2. Environmental Impact Assessment based on Watershed Management. Watershed area is the site for various processes of environmental, economic and social activities, including for its wastes disposal, that make it as a pool of complex environmental problems [11]. Thus it needs a comprehensive approach to analyze and to evaluate any impact of these problems so that the availability of water could be sustained. 420