Mitigation,compensation, and future protection for fish populations affected by hydropower development in the upper Columbia system,Montana, U.S.A.

Pursuant to the Northwest Power Planning Council's Fish and Wildlife Program for the Columbia River system, we estimated losses in fish populations and developed mitigation, compensation, and protection alternatives for reservoirs and downstream river reaches affected by hydropower development in the Flathead and Kootenai River systems in northwest Montana, U.S.A. The construction of Hungry Horse Dam has resulted in estimated annual losses of 65500 migratory juvenile westslope cutthroat and 1965 adult migratory bull trout from the Flathead Lake and River system. In addition, operations of Hungry Horse and Kerr dams caused annual losses conservatively estimated at 96300 river-spawning and 131000 lakeshore-spawning kokanee adults. Water level fluctuations caused by dam operations at Libby and Hungry Horse reservoirs result in: (1) altered thermal stratification, (2) indirect losses in phytoplankton and zooplankton production, (3) direct washout of phytoplankton and zooplankton through dam penstocks, (4) reductions in standing crop of benthic organisms and of insects on the water surface, and (5) reduced fish growth in the late summer and fall. Mitigative measures include: (1) 99.2 and 113.3 m³ s^?1 minimum flows in the Flathead and Kootenai rivers respectively, to protect salmonid eggs and juveniles, (2) improvement of fish passage to restore migrations between the Flathead and Swan systems, and (3) biological rule curves for operations at Libby and Hungry Horse reservoirs. To compensate for fisheries losses, we recommend enhancement of spawning and rearing habitat, introductions of hatchery juveniles, and spawning channels. We recommend protection from further hydropower development for 100 stream reaches (1386 km) for fish species of special concern, and for outstanding sport fisheries. These and other measures will be considered by various agencies in developing an overall fisheries restoration plan which should be flexible, and employ principles of adaptive management. Effectiveness of the plan may be limited by heavy reliance on hatchery fish. Although mitigation efforts may not restore fish populations to pre-dam levels, substantial benefits should be realized.     

“三个代表“与高校学生思想政治工作

“三个代表”是当代高校学生思想政治工作的主题 ,要充分发挥目前高校政治教育的优势 ,采取各种教育手段 ,把“三个代表”重要思想贯穿到整个教育的始终。     

三峡工程运用后宜枝河段平滩河槽形态调整对来水来沙的响应

三峡工程运用后,受上游来沙减少及水库拦沙影响,下泄沙量急剧减少,坝下游宜枝河段发生显著冲刷,平滩河槽形态也相应调整。由于宜昌及宜都河段在河型、河床组成上略有不同,且不同断面的河槽形态沿程变化较大,故采用基于河段平均的方法,分别计算了这两河段2002-2013年的平滩河槽形态参数。计算结果表明:研究时段内两河段的平滩河宽总体变化很小;但宜昌段平滩水深约增加1.3m,而宜都段平均冲深达2.9m;两河段的平滩面积均呈持续增加趋势。在此基础上,建立了河段尺度的平滩河槽形态参数与前5年平均的汛期水流冲刷强度之间的经验关系,用于预测该河段平滩河槽形态的调整趋势。     

2018长江2号洪水期间三峡水库沙峰排沙调度

2018年长江第2号洪水期间,寸滩站洪峰流量59 300 m~3/s,报汛最大含沙量达到4.47 kg/m~3,三峡入库沙量达到了7 440万t,均大于2014~2017年各年的全年入库输沙量,且入库沙峰大、持续时间长。根据泥沙实时监测与预报成果,7月11～20日三峡水库入库和坝前含沙量较大,三峡水库在进行防洪、航运调度的基础上,实施了沙峰排沙调度,将下泄流量42 000 m~3/s一直维持至沙峰通过大坝后。实测资料表明:7月18～20日三峡水库排沙效果明显增强,出库含沙量在0.50～1.20 kg/m~3之间,最大出库输沙率达到48.5t/s,日均出库沙量在370万t左右,按沙峰输移过程统计,沙峰过程排沙比达29%,7月份排沙比达到了31%,取得了较好的排沙效果,有效减轻了库区泥沙淤积。研究成果为进一步完善三峡水库"蓄清排浑"新模式积累了宝贵的经验。     

Predicting Impact Velocities of Developed Jets

Abstract

Dam overtopping often results in the erosion of foundation and abutment materials. To quantify erosion potential, the jet impact velocity at the plunge pool interface must be estimated. Regións of the overtopping jet trajectory through free-fall are termed undeveloped (compact) and developed (individual particles). A physical model was constructed to simulate the developed region of a free-falling jet and to measure the impact velocity of developed jets. The equation derived for estimating the impact velocity of an undeveloped jet (Ervine and Falvey, 1987) was applied to the developed portion. The undeveloped jet estimation equation significantly overestimated the impact velocity of the developed jet. A drag expression was formulated and appended to the undeveloped equation resulting in a new equation, referred to as the Dimensional Equation Technique. The Dimensional Equation Technique was used to estimate developed jet impact velocities to within ± 4 percent.     

Performance of a prototype surface collector for juvenile salmonids at Bonneville Dam's first powerhouse on the Columbia River,Oregon

During April–July 2000, we radio‐tagged and released juvenile Chinook salmon (Oncorhynchus tshawytscha) and steelhead (Oncorhynchus mykiss) to evaluate a prototype surface flow bypass at Bonneville Dam on the Columbia River. The mock bypass, called a prototype surface collector (PSC), had six vertical slot entrances that were each 6 m wide and 12 m deep. The PSC was retrofitted to the upstream face of Bonneville Dam's First Powerhouse. Our objectives were to: (1) assess species‐specific differences in movement patterns and behaviour of fish within 6 m of the face of the PSC, (2) estimate the efficiency and effectiveness of the PSC and (3) evaluate factors affecting the performance of the PSC. We found that 60–72% of the fish, depending on species, detected within 6 m of the PSC entered it. Of the fish that passed the First Powerhouse at turbines 1–6, 79–83% entered the PSC. Diel period was a significant contributor to PSC performance for all species, and day of year was a significant contributor to PSC performance for subyearling Chinook salmon. The PSC was twice as effective (%fish/%flow) as the spillway, passing 2.5:1 steelhead and subyearling Chinook salmon and 2.4:1 yearling Chinook salmon per unit of water. If fully implemented, the PSC would increase the percentage of fish that pass the First Powerhouse through non‐turbine routes from 65–77% (without the PSC) to 76–85% (with the PSC), depending on species. Published in 2008 by John Wiley & Sons, Ltd.     

三峡工程金属结构安装技术的创新与实践

介绍了在三峡工程金属结构安装中,创造的一些新工艺、新技术及其应用实例,并展望这些技术在水利水电工程上的应用前景。     

华电镇雄电厂一期取水口拦沙坎样式试验研究

针对电厂取水口拦沙坎原谩计方案存在的诸多问题,采用"侧面进水、正面排沙"的布置原则,同时考虑向林口水库补水的运行模式.为取水口设计一个拦沙效果好,又能保持流态平顺的拦沙坎是一个极其重要的环节,因此,本试验的主要目的在于通过对三种设计方案的比较分析,选择出最优的拦沙坎设计形式.     

三峡工程碾压混凝土配合比研究

 为加快三峡工程建设，降低工程费用，拟在纵向围堰及三期上游横向围堰采用全断面碾压混凝土修筑。大坝主体建筑物某些坝段或部位也拟采用碾压混凝土。根据设计要求，结合三峡工程的具体情况，对碾压混凝土的配合比进行了系统研究，并提供了其物理力学性能试验成果。     

三峡船闸输水系统反弧门启闭力特性研究

 三峡船闸输水系统阀门设计拟采用双面板式反向弧形门。通过比尺为17的物理模型，对阀门启闭力进行了试验观测， 并分析了启闭力的时均变化过程、启闭力脉动及其频域特性。从减小阀门动水启门力的角度， 对反弧门几何体形进行了优化。