Evaluation of Carrying Capacity Land-Based Layout to Mitigate Flood Risk (Case Study in Tempuran Floodplain, Ponorogo Regency) Novia Lusiana1 Bambang Rahadi2 Tunggul Sutanhaji3 1Environmental and Natural Resources Management Graduate Program University of Brawijaya, Malang, Indonesia 23Laboratory of Environment and Natural Resources Engineering, Department of Agricultural Engineering, Faculty of Agricultural Technology, University of Brawijaya, Malang, Indonesia Email : novialusiana@rocketmail.com, jbrahadi@ub.ac.id, tunggulsutanhaji@yahoo.com

Abstract Floods haves frequently hit Indonesia and have had greater negative impacts. In Javaboth the area affected by flooding and the amount of damage caused by floods have increased. At least, five factors, affect the flooding in Indonesia, including rainfall, reduced retention capacity of the watershed, erroneous design of river channel development, silting-up of the river, and erroneous regional layout. The level of the disastrous risks can be evaluated based on the extent of the threat and susceptibility of a region. One methode for risk assessment is Geographical Information System (GIS)-based mapping. Objectives of this research are: 1) evaluating current flood risk in susceptible areas, 2) applying supported land-based layout as effort to mitigate floodrisk, and 3) evaluating floodrisk for the period 2031 in the Tempuran floodplain of Ponorogo Regency. Result show that the area categorized as high risk covers 104. 6 ha (1. 2%), moderate risk covers 2512. 9 ha (28. 4%), low risk covers 3140. 8 ha (35. 5%), and the lowest risk covers 3096. 1 (34. 9%). Using Regional Layout Design for the years 2011 - 2031, the high risk area covers 67. 9 ha (0.8%), moderate risk covers 3033 ha (34. 3%), low risk covers 2770. 8 ha (31, 3%), and the lowest risk covers 2982. 6 ha (34%). Based on supported land suitability, the high-risk areais only 2. 9 ha (0.1%), moderate risk covers of 426. 1 ha (4. 8%), low risk covers 4207. 4 ha (47. 5%), and the lowest risk covers 4218 ha (47. 6%). Flood risk can be mitigated by applying supported land-based layout as shown by the reduced high-risk area, and the fact that > 90% of the areas are categorized as low or lowest risk of disaster. Keywords : Carrying Capacity, Land Capacity, Flood Risk