Evaluation of Effects of Stormwater Storage/Infiltration Facilities on Improvement of Urban Hydrologic System

近十年来，许多城市化的河流流域引入了侧库/入渗设施，作为改善城市水文循环的有效措施，如洪水径流减少，土壤水分供应，地下水补给等。本研究的主要目的是建立能够处理河流流域局部特征及其变化的基于物理的分布式模型，而不是集总型水文模型。以评估这些现场设施的定量影响。主要研究成果总结如下：(1)自1991年以来，在千叶县船桥市的鄂比河流域开展了降水、流中水位、地下水位、土壤湿度、气温、湿度、净辐射、风速和风向等水文气象项目的自动观测。此外，根据当地政府公布的相关统计数据和相关机构的意见，对城市用水、污水注入、地下水抽取、水田灌溉等人工水文要素进行了调查和估算。(2)在上述观测和调查资料的基础上，定量地阐明了鄂比河流域各水文年的自然和人工水文系统框架。(3)由于生活污水的流入，观测到的水文曲线显示出非常清晰的日循环。利用上述观测的日格局和相关机构提供的供水数据，将观测到的排放量分为自然和人工两部分。(4)利用ARC/INFO软件，以GIS的形式对土地覆盖、土壤水力特性、人口、供水量等流域特征相关数据库进行整理。(5)以GIS数据库为基础，以50m^*50m的网格大小构建了自然成分子模型、人工成分子模型和储渗设施子模型的三维分布式水文模型。在对模型参数进行调优并验证模型有效性的基础上，通过模型模拟，定量评价了几种流域管理实例的效果。少

On-side storage/infiltration facilities have been introduced in many urbanizing river catchments in recent ten years as an effective measure for the improvement of urban hydrologic cycle such as flood runoff reduction, soil moisture supply, groundwater recharge etc..The main objective of this study is to develop not lumped type hydrologic model but physically-based distributed model capable of treating local characteristics as well as their change within the river catchment, in order to evaluate quantitatives effects of those on-site facilities.The major research results are summarized as follows ;(1) Since 1991, automatical observation of hydro-meteorological items including precipitation, water stage in stream, groundwater level, soil moisture, air temperature, humidity, net radiation, wind speed and direction, has been carried out in the Ebi river basin located in Funabashi City, Chiba Prefecture. In addition, artificial hydrologic componemts such as municipal water use, sewage infl … More ow, pumping-up of groundwater, irrigation for paddy fields etc.have been surveyed and estimated, based on related statistics published by located governments and hearing from related agencies.(2) Based on above observed and investigated data, a frame work of the hydrologic system in the Ebi river basin including both natural and artificial components was quantitatively clarified in each hydrologic year.(3) Observed hydrograph shows a very clear diurnal cycledue to the inflow from domestic sewage. The observed discharge was separated into natural and artificial components, using the above observed diurnal pattern and water supply data obtained from related agencies.(4) Data-base related to basin characteristics including land cover, soil hydraulic properties, population, water supply amount were arranged in the form of GIS,by using the software 'ARC/INFO'.(5) A3-dimensional distributed hydrologic model, including natural component sub-model, artificial component sub-model and storage/infiltration facilities sub-model, was constructed in one grid size of 50m^*50m based on the GIS data-base. After tuning model parameters and examining the validation of the model, effects for several cases of basin management were quantitatively evaluated through the simulation using the model. Less