受梯级枢纽运行影响河段,洪枯季航道的水深条件可能发生逆转,航道工程的设计最小通航流量将出现显著变化。根据黔柳江来流特点、大藤峡水利枢纽调度运行规则、红花水利枢纽调峰特征和柳江航道工程对枯水位的影响情况,确定了红花水利枢纽下游近坝段航道的设计最小通航流量。结果表明:受大藤峡水利枢纽运行影响,柳江枯水控制时段将发生显著变化,航道设计最小通航流量具备显著提高的条件;考虑到柳江航道长距离疏挖对红花水利枢纽坝下低水位影响较大和红花水利枢纽日调峰明显,取红花水利枢纽上游柳州水文站6—8月份保证率98%的流量作为下游近坝段航道最小通航控制流量是合适的。研究成果对于受梯级枢纽运行影响的航道设计最小通航流量分析计算具有重要参考意义。

The water depth condition of navigation channel affected by the operation of cascade hydropower stations could experience a reverse between flood season and dry season, significantly altering the minimum design navigable discharge of the waterway. The minimum design navigable discharge of the waterway downstream of Honghua dam was determined in consideration of the inflow characteristics of the Qianjiang and Liujiang Rivers, the dispatch operation rules of the Datangxia Reservoir, the peak regulation features of the Honghua hydropower station, as well as the impact of Liujiang River waterway project on low water level. Results indicated that the control period for low water level of Liujiang River would undergo significant changes due to the impoundment of Datengxia Reservoir, and the minimum design navigable discharge of waterway had the potential to increase remarkably. The extensive dredging of Liujiang River navigation channel substantially impacted the low water level downstream of Honghua dam, and the daily peak regulation of Honghua hydropower station was significant. Consequently, it is suitable to adopt the discharge with a 98% guarantee rate at Liuzhou hydrological station in the upstream of Honghua dam from June to August as the minimum navigable control discharge for the downstream waterway. The findings provide valuable information for the analysis and computation of the minimum design navigable discharge of waterways affected by cascade hydropower stations.