Institute of Natural Resource Sciences, Zurich University of Applied Sciences (ZHAW), Grüental, 8820 Wädenswil, Switzerland.
Institute of Earth Sciences, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Campus Trevano, 6952 Canobbio, Switzerland.
Sci Total Environ. 2017 Jan 1;574:594-604. doi: 10.1016/j.scitotenv.2016.09.101. Epub 2016 Oct 14.
New Swiss legislation obligates hydropower plant owners to reduce detrimental impacts on rivers ecosystems caused by hydropeaking. We used a case study in the Swiss Alps (hydropower company Kraftwerke Oberhasli AG) to develop an efficient and successful procedure for the ecological evaluation of such impacts, and to predict the effects of possible mitigation measures. We evaluated the following scenarios using 12 biotic and abiotic indicators: the pre-mitigation scenario (i.e. current state), the future scenario with increased turbine capacity but without mitigation measures, and future scenarios with increased turbine capacity and four alternative mitigation measures. The evaluation was based on representative hydrographs and quantitative or qualitative prediction of the indicators. Despite uncertainties in the ecological responses and the future operation mode of the hydropower plant, the procedure allowed the most appropriate mitigation measure to be identified. This measure combines a basin and a cavern at a total retention volume of 80,000m, allowing for substantial dampening in the flow falling and ramping rates and in turn considerable reduction in stranding risk for juvenile trout and in macroinvertebrate drift. In general, this retention volume had the greatest predicted ecological benefit and can also, to some extent, compensate for possible modifications in the hydropower operation regime in the future, e.g. due to climate change, changes in the energy market, and changes in river morphology. Furthermore, it also allows for more specific seasonal regulations of retention volume during ecologically sensitive periods (e.g. fish spawning seasons). Overall experience gained from our case study is expected to support other hydropeaking mitigation projects.
瑞士新法规要求水力发电厂所有者减少因水力发电调峰而对河流生态系统造成的不利影响。我们在瑞士阿尔卑斯山的一个案例研究中（水力发电公司 Kraftwerke Oberhasli AG）开发了一种有效且成功的生态评估方法，以预测可能的缓解措施的效果。我们使用 12 个生物和非生物指标评估了以下情景：前缓解情景（即当前状态）、未来增加涡轮机容量但没有缓解措施的情景、以及未来增加涡轮机容量和四种替代缓解措施的情景。评估基于有代表性的水流图和对指标的定量或定性预测。尽管生态响应和水力发电厂未来运行模式存在不确定性，但该程序允许确定最合适的缓解措施。该措施结合了一个盆地和一个洞穴，总保留量为 80,000 立方米，大大降低了水流下降和上升速度，从而大大降低了幼鲑鱼搁浅的风险和大型无脊椎动物漂流。一般来说，这种保留量具有最大的预测生态效益，并且在一定程度上可以补偿未来可能对水力发电运行模式进行的修改，例如由于气候变化、能源市场变化和河流形态变化。此外，它还允许在生态敏感时期（例如鱼类产卵季节）更具体地调节保留量。我们的案例研究中获得的总体经验预计将支持其他水力发电调峰缓解项目。
