YAKUTSK, January 24. /TASS/. Scientists calculated an integral index of water resources' social vulnerability for Yakutia's settlements to forecast high-water risks, said Nikita Tananayev of North-Eastern Federal University and the Melnikov Permafrost Institute (the Russian Academy of Sciences' Siberian branch).

A group of scientists has completed the first stage of Yakutia's Academy of Sciences' complex survey of hydrological risks in the region. The experts have set flood areas for 123 settlements in Yakutia, where 61% of the region's population live.

"Most of the settlements for which we have set flood zones are places where live Yakutia's indigenous peoples, including the Sakha (Yakuts - TASS) - 73.9% of settlements, Evenks - 5.7%, Evens - 4.1%, Yukaghirs, Chukchi and Russian old-timers - 0.8% of settlements. Mainly Russian settlements make 13.8%. For the settlements with set flood areas we have calculated an integral index of water resources social vulnerability," he told TASS.

According to experts, the vast majority of settlements, more than 91%, belongs to the category of moderate social vulnerability, that is, they are in the zone of medium and high risk. Three settlements are characterized by a high social vulnerability of water resources - these are priority areas, which require special attention. On the other hand, in 9% of Yakutia's settlements, the situation is characterized by moderate social stability of water resources - those are the zones of relative well-being.

In the future, scientists plan to calculate the water resources natural vulnerability index, taking into account the climate changes, and to determine a generalized indicator that takes into account both the natural and social vulnerability aspects.

Hydrological risks management, the expert explained, is aimed at cutting probability of dangerous phenomena and, more importantly, at minimizing the damage from them. "In our work, hydrological risks are also structured: natural, man-made, institutional risks, development risks, and possible measures to cut all types of hydrological risks. This is necessary because every type of risk needs optimal management strategies, they have certain characteristics and management processes," he said.

Management practices

The experts have examined the existing organizational structure of water resources and hydrological risks management in the region. They have worked to determine the vulnerability of water resources from climate changes, and also proposed a model for a hydrological safety passport - a document accompanying decision-making in water safety.

They have studied applied practices of hydrological risk management in the region, including in the Arctic zone of Yakutia, on the basis of the UN Sustainable Development Goals, analyzing advantages and disadvantages (SWOT analysis). The experts found that the existing management system has a high degree of inconsistency. "On one hand, the management system architecture, formed in compliance with the federal legislation, is generally of high quality; on the other hand, there is a low quality of the functioning management system at the regional level. The nearest strategic task in water resources management at the level of the Arctic zone of Yakutia is, first of all, to minimize the internal contradictions," the expert believes.

Hazardous hydrological phenomena, in particular floods, have natural causes and socio-economic consequences - material damage, human casualties, disruptions in settlements. The most important natural phenomenon is the climate change. According to forecasts, the sum of positive temperatures and the sum of temperatures above ten degrees in Yakutia are at about 200 degree-days within the period up to 2050. Scientists warn, this will lead to increased evaporation and, consequently, to a decrease in water resources, and the soil desiccation.

At the same time, in recent decades, the annual precipitation has remained unchanged or increased in southern and western Yakutia, and on the upper Kolyma; has decreased slightly in the northwestern and central regions of Yakutia, and decreased noticeably in the Allaikhovsky, Ust-Yansky and Anabar districts. The forecast of future changes in the annual precipitation will make it possible to predict water availability in Yakutia's settlements in the coming decades, scientists say.

"However, as we have shown in this work, it is necessary to take into account that the hazardous phenomena also have socio-economic origins: specifics of developments and settlements, conditions of access to land resources, and natural consequences: the declining biodiversity, the degradation of floodplain landscapes," the expert said.

Floods are one of the acute seasonal problems in the Far East and the Arctic. Thousands of settlements and farms suffer from them every year. The construction of dams and other flood control structures, as well as other preventive measures in the Far Eastern Federal District continues as a response to an order, issued by the Russian president.