圖書典藏及影音數位平台

本計畫的目的為分析氣候變遷對曾文溪及高屏溪水系水資源供水系統的衝擊及重新擬定供需間調配的能力，從水文循環的觀點，掌握雨水、河川水、水庫水及地下水之間受到氣候變遷的影響，進而鞏固區域供水系統之穩定性，並藉過去既有區域供水潛能評估方案，尋求各項新增水資源方案的可能性與適用性，最後在氣候變遷的情境下，建立水資源風險評估機制，將設施風險、系統風險及供水風險同時納入考量，且進行風險管理，研擬氣候變遷下水資源有效運用策略及風險因應策略，以達掌握整體水資源系統之承載能力與風險，做為未來台南及高雄地區推動水資源相關計畫之參考依據，爰辦理「曾文溪及高屏溪水系之水資源風險管理計畫」委託服務計畫。

The purpose of this project is to analyze the impact of climate change on the water supply system of Zengwen and Gaoping River basins and to re-engineer the supply and demand capacity, consolidate the stability of the regional water supply system, establish a water resource risk assessment mechanism, and bring facility risks. System risk and water supply risk are taken into consideration at the same time, and risk management is carried out. The effective use of water resources under climate change and risk response strategies are developed. The short-term goal is to not limit the water in the third stage under the 2015 situation, and the long-term goal is to maintain stable water supply under the influence of climate change. Under the influence of maintaining a stable water supply, in order to grasp the carrying capacity and risks of the overall water resources system, the summary of the project results are as follows: 1. Project area overview (A) This project collects basic data such as meteorology, hydrology and geography in the Zengwen River and Gaoping River basins. (B) This project organizes information on climate change related literature, assessment methods, and techniques. 2. Analysis of hydrological information variation under climate change (A) This project uses the rainfall data of Gaoping and Zengwen River basins to analyze the long-term fluctuation trend of rainfall, and estimates the trend of rainfall with nearly 30 years of rainfall data. From the results, it can be seen that the overall rainfall station has shown a slight increase in the past 30 years. Only the Tianchi Station on the upper reaches of Zengwen River has a significant upward trend, with a trend slope of 50mm/year, which represents an increase in rainfall under long-term data review. (b) This project collects the first aquifer groundwater observation well data from the Pingtung Plain and the Jianan Plain and uses the standardized groundwater index method (SGI) for analysis. In the Pingtung Plain representative station, two low water level periods can be observed. They are 2002~2004 and 2014~2016 respectively. According to the spatial distribution of the groundwater observation wells, the wells are far away from the mainstream section of Gaoping River, and are mainly located in the upstream groundwater recharge area, which represents regional hydrology Geological formations are related to the changing trend of groundwater stations. The SGI360 indicator value of the groundwater level station in the downstream area of Zengwen River shows that the lowest water level in the region during the period from 2002 to 2004, compared with the lower water level in the period from 2014 to 2016, only the upstream Xiaoxin and Xinshi stations are more obvious. The alluvial structure of the Zengwen River alluvial fan has a relatively obvious relationship. (c) The rainfall in the Zengwen River Basin are higher than the base period in the climate change AR4 scenario. The difference between the one-day rainstorm in the 200-year return period calculated by the A1B situation and the base period is the Guanshan Station, followed by the Longmei Station. The 200-day recurrence period is also the largest difference in the Guanshan Station, followed by Longmei. station. The rainfall in the Gaopingxi River Basin in the AR4 situation (A1B) is higher than the base period. The difference between the A1B situation and the base period is the largest in the 200-year return period. (d) The project refers to the results of the previous plan, uses the same conditions to analyze the water supply potential of the water source system, and compares the analysis results to verify the analysis model of the water supply potential. Overall, the difference between the simulation results of the project and the previous project results is less than or equal to 3%, which can reasonably simulate the water supply system of the water system in Zengwen and Gaoping River Basins. 3. Water resources facility inventory and operation (a) The average annual water intake of Baihe Reservoir in Tainan is 24 million tons, including 0.23 million tons for agriculture and 1 million tons for industrial and people’s livelihood. The average annual water intake of Nanhua Reservoir is 227 million tons, of which 231 million tons are for industrial and people’s livelihood; The average annual water intake of the Zengwen wushantou system is 2.283 billion tons, of which 561 million tons are for agriculture and 160 million tons for industrial and people's livelihood. (b) The average water intake of Gaoping in Kaohsiung is 325 million tons, which is mainly responsible for industrial water and people's livelihood. The average annual water intake of Agongdian Reservoir is 24 million tons, including 0.18 billion tons for agriculture and 0.6 billion tons for industrial and people's livelihood; The average annual water intake of the lake reservoir is 114 million tons, mainly supplying 136 million tons of industrial and people's livelihood; the average annual water intake of Fengshan Reservoir is 121 million tons, and its main supply of industrial and people's livelihood is 121 million tons. (c) Surface water The average runoff of rivers in the southern region is about 17.56 billion tons. If the main river system exceeds the probability of 85% as the natural potential ceiling, the total potential energy of surface water from the main water system in the southern region to the estuary of each river system is about 3.87 billion tons per year. The remaining flow may be about 670 million tons per year, and it is concentrated in the period of abundant water. If the new water storage facilities are not stored, it is impossible to increase the stable water supply capacity of the surface water. (d) Groundwater The potential for recharge of groundwater in the southern region is about 1.63 billion tons, of which 850 million tons per year in the Jianan Plain and 780 million tons per year in the Pingtung Plain. In the southern region, only the Pingtung Plain has abundant groundwater, and because there are no reservoirs in the area, most of the residents use groundwater for living, industrial and agricultural water. Although the current natural recharge volume is roughly balanced with the total pumping volume. However, the groundwater in the coastal area adjacent to the fantail has been overused, resulting in subsidence of the stratum and flooding of the rainy area. Only some areas have the remaining groundwater development potential. After assessing the alluvial sectors at the junction of Qishan River and Laonong River, the potential for groundwater development is about 83,000 tons to 91,000 tons per day. If combined with the development of large-scale water storage space, the potential for groundwater development in the region can be Upgraded to 96,000 tons to 118,000 tons per day. 4. Water resources risk assessment and management (a) From the results of current risk assessment, it can be seen that the Nanhua Reservoir and the Wushantou Reservoir in the Tainan area are mainly responsible for people's livelihood and public water use. Therefore, they are medium and high risk. Follow-up measures such as new backup and alternative pipelines should be considered. The reservoir facilities in Kaohsiung area are all slight. Because the current water resource dispatching system is more diversified than when it was originally built, it is more affordable for long-term facility anomalies. Therefore, the impact of the Nanhua Gaoping Unicom tube on the current status is slightly. However, if it is based on short-term dispatch support, Nanhua Gaoping Unicom still plays an important role. In the part of the reservoir siltation, there is no large-scale dredging plan for the Wushantou Reservoir and the Clarion Reservoir. Therefore, the probability of occurrence in the reservoir siltation is high, but the degree of impact is slight. The siltation of the Nanhua Reservoir is a high risk. Therefore, whether the Nanhua Second Reservoir can smoothly promote whether the Nanhua Reservoir can improve the storage capacity and extend the life. In the systemic risk, the use of simulated 2015 scenarios can provide high risk for the lack of water in Tainan and Kaohsiung during the dry season; high turbidity in Gaoping River is also a high risk. In terms of supply and demand risks, the future growth of water in Tainan is a high risk, and the reduction of supply under the influence of climate change in the Zengwen River and Gaoping River Basins are high risk. (b) After comprehensively counting the supply and demand of water resources in the area, the project identified two bottlenecks in the southern water resources system:(1) Water pipeline restrictions at the Gang Xi Pumping Station and (2) Restriction of the back-end pipeline of Nanhua Water Purification. The Gang Xi Pumping Station is equipped with 8 pumping machines. The pumping capacity of each pump can reach 100,000 tons/day, and the total pumping capacity can reach 700,000 tons/day. However, the water pipeline of the Gang Xi Pumping Station is old. Based on safety considerations, the current water transport capacity is only 300,000 tons/day. It is recommended that the water pipeline be improved in the future. The current processing capacity of Nanhua Water Purification Farm is 800,000 tons/day. However, limited to the back-end pipeline can only supply 680,000 tons / day of water. In the future, after the completion of Zengwen Nanhua Unicom Pipeline, it is also subject to this limitation. Therefore, it is recommended to strengthen the water supply capacity of the back-end pipeline in the future. (c) Based on the current and future stages of risk analysis, it is recommended that the assessment be re-implemented every two years for risk management review. If the assessment may affect the main risk project or the important business, the control operation should be revised first. (d) This plan is to analyze the drought situation from October 1, 2018 to May 31, 2019, and to save the effective water storage capacity of 50 million tons of Zengwen-Wushantou Reservoir at the end of May 2019. Discuss how much water should be stored in the Zengwen-Wushantou system on October 1, 2018. In the case of water conservation in agriculture, the effective water storage capacity of the Zengwen-Wushantou Reservoir on May 31 of the following year was 179.9 million tons. Under the very irrigation management measures, the effective water storage capacity of the Zengwen-Wushantou Reservoir on May 31 of the following year was 244.48 million tons. The analysis results show that on October 1, 2018, the effective water storage capacity of the Zengwen-Wushantou Reservoir was 546.5 million tons. Under the agricultural water conservation situation and very irrigation management measures, the effective water storage capacity of the reserved reservoir at the end of May of the next year can reach 50 million tons.