Gaoba Reservoir has strong regulation capacity and plays an important role in cascade development and disaster prevention and reduction in the basin. However, the risks it faces objectively exist, and the consequences of a failure are unimaginable. The ability to empty or lower the water level of reservoirs is a new requirement for dam risk prevention and emergency management in the new stage of economic and social development. We selected 25 typical high dam reservoirs in China for analysis of their emptying capacity, and obtained data on dam type, maximum dam height, dam crest elevation, normal water level, total storage capacity, emptying water level, emptying head ratio, remaining emptying capacity, emptying capacity, emptying time, and average deceleration of reservoir water. The emptying head ratio of Gaoba Reservoir ranges from 17.5% to 71.8%, with an average of 42.7%; The empty storage capacity ratio ranges from 47.2% to 99.2%, with an average of 81.7%; The emptying time ranges from 7.2 to 123 days, with an average of 42.7 days; the reservoir water deceleration rate ranges from 0.71 to 9.03 m/d, with an average of 3.0 m/d. This data can be used as a reference for key issues in the design of reservoir emptying facilities, such as inflow, emptying indicators, start-up conditions, and hierarchical decision-making modes.
Based on the literature review of "Several Thoughts on the Design of High Dam and Large Reservoir Emptying in China's Hydropower Engineering" and "Several Issues Concerning the Setting of Emptying Holes in Panel Dams", the maximum dam height, dam crest elevation, normal water level, total storage capacity, emptying water level, emptying head ratio, emptying remaining storage capacity, emptying capacity ratio, and emptying time of 25 typical high dams were obtained. The relationship between the maximum dam height, total storage capacity, and the rate of water level drop in 25 typical high dams was summarized, and the emptying head ratio, emptying capacity ratio, emptying time, and average rate of water drop in some high dam reservoirs in China during non flood season were further analyzed.
Data will be obtained through literature review to summarize the maximum dam height, dam crest elevation, normal water level, total storage capacity, emptying water level, emptying water head ratio, emptying remaining storage capacity, emptying storage capacity ratio, and emptying time of 25 typical high dams. The average water drop rate of the 25 typical high dams will be obtained by dividing the normal water level by emptying time. Draw the scatter plot relationship between dam height and average deceleration of reservoir water, as well as the scatter plot relationship between reservoir capacity and average deceleration of reservoir water in EXCEL, and draw histograms of the mean values of emptying head ratio, emptying capacity ratio, emptying time, and average deceleration of reservoir water for different dam types.
(1) The emptying head ratio ranges from 17.5% to 71.8%, with an average of 42.7%. That is to say, the vented water head accounts for 42% of the vertical distance from the normal water level to the dam foundation elevation. Among them, the average emptying head ratio of 13 rockfill dams is about 46.3%, the average emptying head ratio of 8 concrete arch dams is about 40.2%, and the average emptying head ratio of 4 concrete gravity dams is about 36.2%.
(2) The empty storage capacity ratio ranges from 47.2% to 99.2%, with an average of 81.7%. That is to say, the storage capacity that can be emptied accounts for about 82% of the total storage capacity. Among them, the average empty storage capacity of 13 rockfill dams is about 79.3%, the average empty storage capacity ratio of 8 concrete arch dams is about 84.6%, and the average empty storage capacity ratio of 4 concrete gravity dams is about 83.4%.
(3) The emptying time ranges from 7.2 to 123 days, with an average of 42.7 days. Among them, the average emptying time of 13 rockfill dams is about 42.9 days, the average emptying time of 8 concrete arch dams is about 42.4 days, and the average emptying time of 4 concrete gravity dams is about 42.4 days.
(4) The deceleration of reservoir water ranges from 0.71 to 9.03 m/d, with an average of 3.0 m/d. Among them, the average rate of water decline in 13 rockfill dams is about 3.0 m/d, The average water drop rate of 8 concrete arch dams is about 3.4 m/d, and the average water drop rate of 4 concrete gravity dams is about 2.8 m/d.
(5) The larger the storage capacity of Gaoba Reservoir, the lower the emptying water level, the greater the technical difficulty of deep hole setting, and the longer the time required for emptying. The total storage capacity of the Nuozhadu hydropower station reservoir is 23.7 billion m3, with an emptying capacity ratio of 84.4%, but the emptying time is 102 days; the total storage capacity of the Longtan hydropower station reservoir is 27.3 billion m3, with an emptying capacity ratio of 85.7%, and the emptying time is 123 days.
According to the analysis, the emptying capacity of Gaoba Reservoir is affected by engineering characteristic parameters such as total storage capacity, emptying water level, and dam type, which is consistent with actual engineering practice. It has certain reference significance for the design of reservoir emptying facilities and emergency management in China's water conservancy and hydropower engineering industry.
| # | number | name | type |
| 1 | 2021YFC3090105 | Safe and efficient venting and intelligent control technology for high dams and large reservoirs | National key R & D plan |
This work is licensed under
CC BY 4.0 (Creative Commons Attribution 4.0 International License).
CSTR:11738.11.NCDC.NHRI_DAM.DB6875.2025
10.12072/ncdc.nhri_dam.db6875.2025
