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为掌握滇池流域花卉大棚种植区的非点源污染特征,提高和改善滇池水环境质量,本研究选取呈贡县斗南村花卉大棚种植区作为研究对象,在实测降雨径流数据的基础上,通过建立Storm Water Management Model模型分别对全年连续降雨条件下和典型设计降雨条件下的降雨径流水质、水量进行了模拟.研究结果表明:1)模型的流量、化学需氧量(COD_(Cr))、悬浮物(SS)、总氮(TN)和总磷(TP)的Nash-Sutcliffe效率系数分别为0.858、0.835、0.803、0.712和0.752,能够较好地模拟研究区域的水质、水量变化.2)研究区域的平均径流系数为0.59,CODCr、SS、TN和TP的单位面积负荷率分别为118.34、82.90、54.64和5.46 kg/(hm~2·a),TN和TP是主要控制的污染物.3)各污染物浓度峰值的出现时间均早于流量峰值出现的时间,因此对滇池东岸花卉大棚种植区应进行污染物尤其是TP、TN浓度与流量错峰控制. 相似文献
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Urbanization strongly changes natural catchment by increasing impervious coverage and by creating a need for efficient drainage systems. Such land cover changes lead to more rapid hydrological response to storms and change distribution of peak and low flows. This study aims to explore and assess how gradual hydrological changes occur during urban development from rural area to a medium‐density residential catchment. The Stormwater Management Model (SWMM) is utilized to simulate a series of scenarios in a same developing urban catchment. Sub‐hourly hydro‐meteorological data in warm season is used to calibrate and validate the model in the fully developed catchment in 2006. The validated model is then applied to other cases in development stage and runoff management scenarios. Based on the simulations and observations, three key problems are solved: (1) how catchment hydrology changes with land cover change, (2) how urban development changes pre‐development flows, and (3) how stormwater management techniques affect catchment hydrology. The results show that the low‐frequency flow rates had remarkably increased from 2004 to 2006 along with the increase of impervious areas. Urbanization in the residential catchment expands the runoff contributing area, accelerates hydrological response, raises peak flows in an order of magnitude of over 10, and more than doubles the total runoff volume. The effects of several LID controls on runoff hydrograph were simulated, and the techniques were able to reduce flows towards the pre‐development levels. However, the partly restored flow regime was still clearly changed in comparison to the pre‐development flow conditions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Assessment of the SWMM model uncertainties within the generalized likelihood uncertainty estimation (GLUE) framework for a high‐resolution urban sewershed 
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下载免费PDF全文 This research incorporates the generalized likelihood uncertainty estimation (GLUE) methodology in a high‐resolution Environmental Protection Agency Storm Water Management Model (SWMM), which we developed for a highly urbanized sewershed in Syracuse, NY, to assess SWMM modelling uncertainties and estimate parameters. We addressed two issues that have long been suggested having a great impact on the GLUE uncertainty estimation: the observations used to construct the likelihood measure and the sampling approach to obtain the posterior samples of the input parameters and prediction bounds of the model output. First, on the basis of the Bayes' theorem, we compared the prediction bounds generated from the same Gaussian distribution likelihood measure conditioned on flow observations of varying magnitude. Second, we employed two sampling techniques, the sampling importance resampling (SIR) and the threshold sampling methods, to generate posterior parameter distributions and prediction bounds, based on which the sampling efficiency was compared. In addition, for a better understanding of the hydrological responses of different pervious land covers in urban areas, we developed new parameter sets in SWMM representing the hydrological properties of trees and lawns, which were estimated through the GLUE procedure. The results showed that SIR was a more effective alternative to the conventional threshold sampling method. The combined total flow and peak flow data were an efficient alternative to the intensive 5‐min flow data for reducing SWMM parameter and output uncertainties. Several runoff control parameters were found to have a great effect on peak flows, including the newly introduced parameters for trees. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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以SWMM 模型为平台构建已建城市区域排涝模型,以广州市芳村高尔夫地块为研究区域,基于研究区域实测降雨、径流等资料对模型进行参数率定和验证,模拟在不同暴雨重现期下已建城市区域雨水管网的排涝能力。研究结果表明：该区域遭遇2 a 一遇暴雨时,J14、J15 和J31 等3 个排水节点出现积水;当遭遇5 a 一遇时,J15 片区和J31 节点出现较为严重的积水,其中J15 和J31 节点积水量分别达到1 674、546 m³;积水时间分别为0.5、0.4 h。针对研究区域排水管网排涝能力偏低的现状,建议结合LID（Low Impact Development）措施,削减暴雨洪峰流量,提高区域排涝能力。文章构建的已建城市排水管网排涝能力评估方法,可识别区域主要积水黑点及管道满流管段,提供了一种动态、定性和定量评估排水管网能力的方法。 相似文献
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Maria Clara Fava Maurizio Mazzoleni Narumi Abe Eduardo Mario Mendiondo Dimitri P. Solomatine 《水文科学杂志》2020,65(7):1096-1111
ABSTRACTPoorly monitored catchments could pose a challenge in the provision of accurate flood predictions by hydrological models, especially in urbanized areas subject to heavy rainfall events. Data assimilation techniques have been widely used in hydraulic and hydrological models for model updating (typically updating model states) to provide a more reliable prediction. However, in the case of nonlinear systems, such procedures are quite complex and time-consuming, making them unsuitable for real-time forecasting. In this study, we present a data assimilation procedure, which corrects the uncertain inputs (rainfall), rather than states, of an urban catchment model by assimilating water-level data. Five rainfall correction methods are proposed and their effectiveness is explored under different scenarios for assimilating data from one or multiple sensors. The methodology is adopted in the city of São Carlos, Brazil. The results show a significant improvement in the simulation accuracy. 相似文献
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A modelling approach to assessing variations of total suspended solids (tss) mass fluxes during storm events 下载免费PDF全文
下载免费PDF全文 Connections between the catchment hydrology and accumulation, washoff and transport of pollutants in wet weather greatly affect the management of urban drainage and its wet‐weather effluents. In recent years, the concept of the first flush has gained on prominence and was further developed for analyzing the interaction between the hydrology and transport of runoff pollutants. One of the most important definitions of the first flush can be derived from the analysis of the m(v) curves (i.e. the curves in which the normalized cumulative pollutant mass is plotted vs the normalized cumulative runoff volume). Indeed the m(v) curves, indicating the distribution of pollutant mass versus volume in wet‐weather flow (WWF) discharges, are commonly used for comparing pollutant discharges for different rainfall events and catchments. In this study, the m(v) curves were used to define the concepts of flow‐limited and mass‐limited WWF events. These two different behaviours have been analysed for rainfall/runoff events observed in the urbanized part of the Liguori catchment in Cosenza (Italy). In order to advance the understanding of the intra‐event variability of m(v) curves, the mathematical rainfall/runoff model Storm Water Management Model of the US Environmental Protection Agency (SWMM) was calibrated for eight observed rainfall/runoff events and the differences between observed and simulated m(v) curves were analysed. The results showed a good correlation between the observed and simulated m(v) curves, and this finding offers further benefits in SWMM model calibration. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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针对强降雨引起的城市积涝以及相应次生灾害等问题,提出了一种基于暴雨洪水管理模型、GIS技术以及DEM数据、排水管网数据、降雨数据等数据的建立南京市暴雨积涝模型的方法,并利用该模型模拟了径流及淹没效果。结果显示:该模型是利用经验值率定方法对模型参数进行率定,率定结果较为符合实际情况,因此该模型能较好地模拟南京市的降雨积涝情况。通过对不同类型的降雨数据进行模拟分析,得出径流量的大小与降雨量强烈正相关,相关系数达0.9以上。径流的产生量还与降雨历时和平均降雨强度等其他因素有关。虽然南京主要降雨为峰值小、平均强度低的小雨,但是当降雨量超过设计排涝能力时,在地势低洼的地区容易出现积涝。 相似文献
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Modeling hydrological responses of karst spring to storm events: example of the Shuifang spring (Jinfo Mt., Chongqing,China) 总被引：4，自引：0，他引：4
Reproduction of hydrographs at karst springs has been an approach of understanding the karst aquifer, which normally acts
as drains for the groundwater flow. However, its numerical modeling is difficult since factors for the internal geometry and
connectedness are unknown and hard to quantify. Hydrographs of the karst aquifer with well-developed conduits in Shuifang
spring catchment were obtained from the automatic gauging station at the spring orifice. Data as to the conduit system were
also obtained based on results and analyses of tracer tests. With these data, the hydrological responses of Shuifang spring
to storm events were simulated by storm water management model (SWMM) developed by USA EPA (Environmental Protection Agency).
Nash–Sutcliffe efficiencies are used to compare the computed flow to the observed, which are 0.95 and 0.92 for calibration
and validation. SWMM was verified and applicable in karst conduit drainage system. The model illustrated correctly quick recharge
through conduits and slow and low inflow from the fissured aquifer matrix. The SCS-CN (soil conservation service-curve number)
infiltration method was used for computation of losses and runoff. Field tests indicated that permeability was extremely high
but different in karst area, which was less sensitive to the computed runoff when exceeded the common value provided by SWMM.
Therefore, an improved quantitative infiltration model for karst area will make SWMM possible to be a useful tool for assessing
and reproducing spring hydrographs. 相似文献
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以北京市大红门排水片为例,构建基于SWMM(Storm Water Management Model)的城市雨洪模型,并基于GLUE方法(Generalized Likelihood Uncertainty Estimation)对模型参数的不确定性进行了分析。结果表明,所建城市雨洪模型能够较好的模拟区域的雨洪过程。在模型参数中,管道曼宁系数、不透水区洼蓄量以及河道曼宁系数的不确定性对模型结果的影响较为显著。GLUE方法能够在分析模型结果不确定性的同时给出敏感性参数,为城市雨洪模型的参数率定和进一步研制提供了有效工具。 相似文献