Abstract

This paper examines the operation of the water management system in the Angara River basin in periods when the water level conditions deviate from the norm. Analysis of the actual water management regimes in reservoirs constituting the Angara cascade over the last 30 years shows that in high- and especially low-water years, the needs of water users are not satisfied with reliability, and the statutory requirements are not fulfilled to the full extent. Analysis of the water management system operation in the Angara River basin in the best-known low-water years confirms this. Aside from climatic changes in the basins of Lake Baikal and the Angara River, the main causes of this situation are the current legal framework and the water management system based on it. This article also discusses other causes of the overall decrease in reliability and stability of the water management system. A universal stability indicator is proposed: a statutory water provision range for each water user is determined taking the existing conditions and restrictions into account. The possible and permissible operation regimes for reservoirs of the Angara cascade have been modeled for various variants based on the statistical streamflow data collected over a 115-year monitoring period. For each of the modeled variants, water provision estimates were obtained taking the statutory requirements and restrictions into account. Since the climate and hydrological parameters in the basins of Lake Baikal and the Angara River have significantly changed over the last 2 decades, an additional scenario was produced for a prolonged low-water period. The results made it possible to identify the most efficient (sustainable) reservoir operation variant that satisfies the needs of water users and consumers in water resources in a better way and complies with the main current requirements and restrictions. To enhance the stability of the water management system in the Angara River basin, it is recommended to amend and supplement the existing legal framework.

中文翻译：

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不同水位条件下安加拉河流域水资源管理系统的稳定性

摘要

本文考察了安加拉河流域水位条件偏离正常时期的水资源管理系统的运行情况。分析安加拉梯级水库近 30 年来的实际水管理制度表明，在高水特别是低水年，用水者的需求可靠性不满足，法定要求不满足全范围。对安加拉河流域最著名的低水年水资源管理系统运行的分析证实了这一点。除了贝加尔湖和安加拉河流域的气候变化外，造成这种情况的主要原因是现行的法律框架和以此为基础的水资源管理制度。本文还讨论了水管理系统可靠性和稳定性整体下降的其他原因。提出了一个通用的稳定性指标：考虑到现有条件和限制，确定每个用水户的法定供水范围。根据 115 年监测期间收集的统计流量数据，已针对各种变体对 Angara 梯级水库的可能和允许运行制度进行了建模。对于每个建模的变体，在考虑法定要求和限制的情况下获得了供水估计值。由于贝加尔湖和安加拉河流域的气候和水文参数在过去 20 年中发生了显着变化，为长期低水期产生了额外的情景。结果使得确定最有效（可持续）的水库运行变体成为可能，该变体以更好的方式满足水资源用户和消费者的需求，并符合当前的主要要求和限制。为增强安加拉河流域水资源管理系统的稳定性，建议修改和补充现有的法律框架。