湖泊水力调控对河湖连通伴生洪水风险的缓释影响  

Mitigation of the lake hydraulic regulation on the accompanied flood risk in an Interconnected River System Network

作　　者：张晨[1] 郑云鹤 刘殷竹 于若兰 高学平[1] ZHANG Chen;ZHENG Yunhe;LIU Yinzhu;YU Ruolan;GAO Xueping(State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300350

出　　处：《水利学报》2022年第3期316-324,共9页Journal of Hydraulic Engineering

基　　金：国家重点研发计划项目(2018YFC0407203);国家自然科学基金项目(52079089)。

摘　　要：河湖水系连通是国家治水、用水的重要战略手段,复杂的河湖连通工程往往伴随着系列风险,其中如何量化评估湖泊水力调控对河湖连通风险的影响,有待深入研究。本文利用Vine Copula函数与水动力模型模拟技术,以沂沭泗水系下游河湖连通工程为例,研究了不同洪水重现期下,骆马湖水力调控对河湖连通伴生洪水风险的定量影响。结果表明,发生50年一遇洪水时,中运河流量、流速均为中风险,若未对骆马湖进行调控,当入湖流量达到11046 m^(3)/s时,下游新沂河河道超过62%的断面均出现水位或流速风险;若将骆马湖起调水位由23.5 m降至22.5 m,即使入湖流量高达12672.6 m^(3)/s,下游河道约80%的断面洪水风险仍可处于低风险,近42%的断面进入缓冲区。但是,当沂沭泗流域全境遭遇百年一遇洪水时,骆马湖调控作用将失效。研究发现,与河河连通相比,湖泊水力调控有效提升下游河道水深、流速风险安全阈值,对连通伴生洪水风险具有缓释作用。The Interconnected River System Network(IRSN)is an important and complex project for water resources management,which is prone to be accompanied by a series of risks.It is difficult to quantitatively assess the impact of lake hydraulic regulation on the risk of river-lake connectivity.To address this issue,we investigated the quantitative impact of Lake Luoma hydraulic regulation on the accompanied flood risk in the lower reaches of Yishusi IRSN under different flood return periods,by coupling Vine-Copula function and hydrodynamic model.The results show that the medium risks are exhibited for the flow,water level,and velocity in the Middle Canal,respectively,during a flood with a 50-year return period.Without Lake Luoma hydraulic regulation,more than 62%channel sections of the downstream Xinyi River are at medium or high risks when the inflow reaches 11,046 m^(3)·/s.While after regulation(i.e.,decrease in the original regulating water level of Lake Luoma from 23.5 m to 22.5 m),80%of the downstream river cross-sections could still be at low risks even if the inflow reaches 12,672.6 m^(3)·/s.Consequently,about 42%of the cross-sections at medium or high risks shifts to the low risks.However,the regulation effect of Lake Luoma will fail under a 100-year flood return period throughout the Yishusi basin.It is found that lake hydraulic regulation can effectively improve the risk safety threshold of the water depth and flow velocity in the lower reaches of Yishusi IRSN and has a mitigative effect on the accompanied flood risk in IRSN.

关 键 词：河湖连通 水力调控 洪水风险 风险缓释 风险分析模型 沂沭泗水系 

分 类 号：TV697.1[水利工程—水利水电工程]