ИСТИНА

The research is concentrated on creating the system of quantitative evaluation of natural flood risk for the territory of Russian Federation. This system takes into account natural and social preconditions of flood forming. The taxonomical units are the federal subjects because of several reasons: planning of flood reducing activities and its financing, collecting the hydrological and meteorological information, planning of economic and social activities usually carries out on federal and municipal level. To create the complex system of quantitative evaluation of natural flood risk there were solved two main goals – to define the most important hydrological characteristics (which determine the potential flood) and social-economic indicators (which show economic conditions on the one hand and the estimation of potential finance loss on the other). The main natural hydrological characteristics are: maximal depth of floodplain inundation; probability of water levels of riverside areas flooding; total duration of floodplain inundation; part of inundated area (compared to federal subject area); reach of river channel with the most probable floodplain inundation, which is defined by riverbed process type. The main characteristics of social-economic vulnerability are: population density; part of population which lives on potential floodable territory; human development index; long term assets; anthropogenic conditionality of natural disaster risk. According to expert opinions the most significant factors are the total duration of inundation and the part of population which lives on potential floodable territory. Flood risk is determined by these two groups of factors. Natural flood is multiple-factorial phenomenon and the risk assessment requires multivariate analysis. One of the methods of quantitative non-parametric analysis is PATTERN (Planning Assistance Through Technical Relevance Number). The final result of the research is the typological demarcation of Russian Federation by flood risk, expressed in numerical values for each federal subject. The flood risk is classified into 5 classes – from “low risk” to “extremely high risk”. The map of potential flood risk was created according to this typological classification. The typological classification of flood risk was verified on the different data. It corresponds to the list of the most vulnerable regions and regions with the highest flood losses. Also numeric values of natural flood risk and social-economic vulnerability correspond to the prevented damage data (correlation coefficient is 0.68). The highest potential flood risk is typical to Zabaykalsky, Krasnoyarsky kray, Kabardino-Balkaria and Severnaya Osetia republics. The safest regions are Vologodskaya oblast, Karelia and Altay republics.