基于InfoWorks ICM的城市河网调控与分析--以福州市仓山区龙津阳岐片区为例

InfoWorks ICM-based urban river network regulation and analysis:A case study of Longjin Yangqi area in Cangshan District,Fuzhou City

针对典型感潮河网地区水环境污染日趋严重与洪涝灾害频发的问题,为优化河网水动力和降低河道漫溢风险,基于Info Works ICM(integrated catchment management)模型建立福州市仓山区龙津阳岐片区城市水文模型与一维河网水动力耦合模型,以2022年6月14日实测降雨及河道水位数据对模型参数进行校准,平均纳什效率系数为0.78,平均洪峰误差为1.5%。设计并模拟3种晴天工况和3种“卢碧”台风雨天工况,结果表明:晴天从无调控到工况3,随着引水量的增加,河网平均流速逐步增加,总体增加66.4%,河道水动力提升显著;雨天从原有调控工况到工况3,随着河道预降水位值增大,关键断面平均超警历时逐步减少,总体下降73%,河道漫溢风险明显降低。构建河网水文水动力耦合模型和工况优选,可为仓山区进一步提升河网水动力与城市汛期洪涝灾害防治能力的方案制定提供决策依据,也可为其他同类研究提供借鉴。

With the development of urbanization,the natural hydrological cycle has been affected and the natural storage capacity of the urban river network has been weakened,making the city more prone to flooding..For the typical tide-sensitive river network area with frequent flooding and increasingly serious water environment pollution,an urban hydrological model and a one-dimensional river network hydrodynamic model were developed and coupled based on InfoWorks ICM for the Longjin Yangqi area in Cangshan District,Fuzhou City.The model parameters were calibrated using the measured rainfall and river level data on June 14,2022,with a Nash efficiency coefficient of 0.78 and a flood error of about 1.5%.Designed and simulated 3 types of sunny working conditions and 3 kinds of"Lupi"typhoon rainy day working conditions.The tide level of the sunny day scenario was selected by the tide level eigenvalue method,with March 18,2021,as the typical tide level of the Min River and January 27,2021,as the typical tide level of the Wulong River for the sunny day scenario.The rain scenario used the rainfall and tide level of typhoon"Lupi"on August 5,2021.The average flow velocity of river network VA was considered in the sunny day scenario,and the average over-alarm time TA was considered in the rainy day scenario,and the simulation results of different conditions were analyzed in different scenarios.The results show that the flow velocity of the river network in the whole area reached 0.751,0.96,1.159,and 1.250 m/s under no regulation and 3 working conditions,respectively,and the average flow velocity of the river network increased gradually from no regulation to working condition 3,with a total increase of 0.499 m/s.The results meet the suitable ecological flow velocity in the hamlet area,and the river hydrodynamics improved significantly.Under 3 kinds of rainy day working condition regulation,the average over-warning time at the key section of the river network was reduced by 31.19%,54.13%,and 73.09%,respectively,compared with the original condition.The hydrodynamic model of the river network in the urban area was constructed based on InfoWorks ICM,and the coupling between the urban hydrological process and the river network confluence process was realized.The average Nash efficiency coefficient was 0.78,indicating that the model is suitable for simulating and analyzing the river network scenarios in the area.The average flow velocity of the river network increased gradually from no regulation to working condition 3 on sunny days,with a total increase of 0.499 m/s.The results met the suitable ecological flow velocity in Kurama District,and the river hydrodynamics improved significantly.Rainy day"Lupi"typhoon scenario from the original regulation of working conditions to working conditions 3,the average over-alarm time of key sections gradually reduced a total reduction of 238 min,an overall decrease of 73%.The improvement program to the original program of river flood control and drainage effect is obvious.Constructing the coupled hydrological-hydraulic model of the river network and the preferred working conditions can provide a decision basis for the formulation of the plan to further improve the hydrodynamics of the river network and urban flooding prevention and control capacity in the Cangshan district,and can also provide a reference for other similar studies.