成都市某区暴雨径流过程模拟分析

为提高城市雨洪管理的效率,最大限度地减少暴雨洪水带来的危害,针对城市防洪排涝的需要,在分析成都市某区降雨径流规律后,建立了该区暴雨径流模拟的数学模型,有助于采取相应措施充分利用雨洪资源。通过对雨洪过程模拟验证表明,模型适合该区域的实际情况,具有一定的合理性和可靠性。     

WATER QUALITY TRAP EFFICIENCY OF STORM WATER MANAGEMENT BASINS1

ABSTRACT: While the quality of rivers has received much attention, the degradation of small streams in upland areas of watersheds has only recently been recognized as a major problem. A major cause of the problem is increases in nonpoint source pollution that accompany urban expansion. A case study is used to examine the potential for storm water detention as a means of controlling water quality in streams of small watersheds. The storm water management basin, which is frequently used to control increases in discharge rates, can also be used to reduce the level of pollutants in inflow to receiving streams. Data collected on a 148-acre site in Maryland shows that a detention basin can trap as much as 98 percent of the pollutant in the inflow. For the 11 water quality parameters, most showed reductions of at least 60 percent, depending on storm characteristics.     

A SYSTEMS STUDY OF STORM RUNOFF PROBLEMS IN A NEW TOWN1

A system study was conducted on the use of a large number of small reservoirs dispersed throughout an urban community as a means of storm water pollution control. The study was based on an area within the “new city” of Columbia, Maryland. Water collected and stored in the reservoirs is treated for release or use in meeting sub-potable and potable water demands in the community. Design and performance criteria were developed for such a system. A simulation model and a computerized evaluation technique were used to select the optimal locations and system configurations. The results of this study indicated that such a system would be less expensive than a conventional engineering approach to storm water pollution control. Further, the benefits derived from use of the storm water as a water supply can offset a portion of the cost of pollution control. Several secondary benefits also result from this concept including erosion and sediment control, storm flow dampening, and recreational facilities. A program is now underway to demonstrate this concept in Columbia, Maryland.     

Impacts of Climate Change on Extreme Precipitation Events Over Flamingo Tropicana Watershed1

Abstract: Climate change, particularly the projected changes to precipitation patterns, is likely to affect runoff both regionally and temporally. Extreme rainfall events are expected to become more intense in the future in arid urban areas and this will likely lead to higher streamflow. Through hydrological modeling, this article simulates an urban basin response to the most intense storm under anthropogenic climate change conditions. This study performs an event‐based simulation for shorter duration storms in the Flamingo Tropicana (FT) watershed in Las Vegas, Nevada. An extreme storm, defined as a 100‐year return period storm, is selected from historical records and perturbed to future climatic conditions with respect to multimodel multiscenario (A1B, A2, B1) bias corrected and spatially disaggregated data from the World Climate Research Programme's (WCRP's) database. The cumulative annual precipitation for each 30‐year period shows a continuous decrease from 2011 to 2099; however, the summer convective storms, which are considered as extreme storms for the study area, are expected to be more intense in future. Extreme storm events show larger changes in streamflow under different climate scenarios and time periods. The simulated peak streamflow and total runoff volume shows an increase from 40% to more than 150% (during 2041‐2099) for different climate scenarios. This type of analysis can help evaluate the vulnerability of existing flood control system and flood control policies.     

Applicability of sustainable urban drainage systems: an evaluation by multi-criteria analysis

Urban flooding has become more serious and worldwide in recent years, especially in the big cities of developing countries. This study uses a multi-criteria analysis (MCA) approach to evaluate the applicability of sustainable urban drainage systems (SUDS), a flood control measure, in the central part of Ho Chi Minh City, Vietnam. The output of the personal computer storm water management model along with interviews with 140 households was used to assess the efficacy and acceptability of four SUDS alternatives: rainwater harvesting, green roof, urban green space and pervious pavement. On technical performance, green roof was the best alternative, followed by pervious pavement, urban green space and rainwater harvesting. Results of the social survey, however, diverged largely from the results of the technical assessments. In particular, people generally prefer public SUDS such as urban green space and pervious pavements to household solutions. With respect to the MCA, we applied four different procedures: Borda count, pair-wise voting, range of value and analytic hierarchy process. Despite some differences, the integrated results from MCA largely agree that urban green space is the most favourable type of SUDS, followed by green roof, pervious pavement and rainwater harvesting.     

WATER RESERVOIR SYSTEMS1

. Water Reservoir Systems were investigated for urban areas as an alternative or complement to storm water drainage systems for flood control which could provide benefits in water conservation and reduce drainage system costs. The study consisted of: (1) gathering of engineering data on the topographical, hydrological, and precipitation characteristics of the area and urban development and economic statistics     

THE EFFECT OF MAINTENANCE ON STORM WATER DETENTION BASIN EFFICIENCY1

ABSTRACT: Storm water detention is an effective and popular method for controlling the effects of increased urbanization and development. Detention basins are used to control both increases in flow rates and sedimentation. While numerous storm water management policies have been proposed, they most often fail to give adequate consideration to maintenance of the basin. Sediment accumulation with time and the growth of grass and weeds in the emergency spillway are two maintenance problems. A model that was calibrated with data from a storm water detention basin in Montgomery County, Maryland, is used to evaluate the effect of maintenance on the efficiency of the detention basin. Sediment accumulation in the basin caused the peak reduction factor to decrease while it increased as vegetation growth in the emergency spillway increased. Thus, the detention basin will not function as intended in the design when the basin is not properly maintained. Thus, maintenance of detention basins should be one component of a comprehensive storm water management policy.     

EFFECTIVE WATER RESOURCES MANAGEMENT IN THE URBAN SETTING1

Water resources management in the urban areas of the United States to be effective must include dimensions far beyond water supply and sewerage. This paper concerns itself with those problem areas of water resource management outside of potable water supply and sanitary sewers. These areas include flood plain management, greenways and blueways, storm water, vistas of waterways, and other attributes of living in or near a water-related environment. The perceptions and attitudes of the concerned public and community power structure must be known in order to manage the water environment effectively. Methods of measuring these perceptions and attitudes are described and ways in which the resulting citizen-resource can be tapped and used as a management device are explored.     

SIMULATION OF THE EFFECTS OF URBANIZATION ON BASIN STREAMFLOW1

ABSTRACT: The hydrologic modeling of streamflow in the Waterford River Basin has been conducted as part of comprehensive investigations of the effects of urbanization on water resources in the basin. Using a detailed input data base, continuous simulation of streamflow in the study area has been done by means of the HSPF model, which has been calibrated for the existing conditions and then applied to several future land use scenarios. The basin climate and geology contribute to high conversion of precipitation into streamflow under the existing conditions. Consequently, future urban development in the study basin should not increase the annual streamflow, but would contribute to increases in peak flows and the incidence of flooding because of the increased speed of runoff. If the impervious area in the basin is doubled, the peak flows may increase by about 20 percent.     

DUAL PURPOSE DETENTION BASINS IN STORM WATER MANAGEMENT1

Storm water management contributes to flood hazard mitigation; but new approaches now being developed consider also the reduction in particulate pollution and stream erosion. Such approaches involve retardation of storm runoff, or detention programs of some kind, and detention basins are usually required if large storms are to be controlled. The usual concept is that future storms occurring after development should have no more adverse effect than similar storms would have had before development; but a number of different criteria are being used. If control of storms of different sizes is required, only a small amount of additional capacity is required to obtain retention of particulate pollution in the same basin. In at least three different parts of the country, such dual purpose detention basins are being required of developers. In such programs the developers bear the cost, the governmental contributions are not involved.     

ANALYZING URBANIZATION IMPACTS ON PENNSYLVANIA FLOOD PEAKS1

ABSTRACT: The impact of man made change on the hydrology of developing watersheds is frequently measured in terms of the ratio: flood peak after development to flood peak before development over a range of return periods. However, the analysis of urbanization effects on flood frequency presents a vexing problem because of a general lack of flood data in urban areas and also because of nonstationarity in the development process. Clearly, the flood peak ratio depends on the impervious fraction and percent of basin sewered and these factors have been taken into account in recent urban flood peak models. In genral, these models are developed either by: (1) split sample analysis of available annual flood data, or (2) by computer simulation using mathematical watershed models capable of representing man made changes. The present paper discusses the results of work in progress to characterize the impact of urbanization on small developing watersheds in Pennsylvania.     

FLOOD PLAIN MODELING1

Computer simulation of river basin hydrology has rapidly progressed from an interesting academic exercise to a practical engineering procedure of increasing utility. Mathematical models of the many interrelated processes which occur in a basin have been developed along with efficient numerical procedures for their solution. The present paper is concerned with a particular model which has been used to describe the transformation of a temporally and spatially varying rainfall into a time history of stage and discharge on a flood plain. Although developed principally as a model of the physical processes involved, it is envisioned that the model can serve as one component of an information system for flood plain planning and management. The model consists of the following elements: (i) a rainfall simulation which generates stochastic inputs to the model according to specified rainfall statistics, (ii) a catchment-runoff model which converts the rainfall to surface runoff, (iii) a flood stage model which converts the surface runoff to time histories of flood stage and discharge. The model has been used to investigate the effect of various structural flood control measures in a basin and, in particular, to establish frequency-stage information for each of these. Of particular interest in development of the model have been recurring and partially unanswered questions relative to the proper balance among availability of data for use in the model, data requirements of the model and the objectives of the outputs produced by the model.     

ACCUMULATION OF AS,NI, CU,AND PB IN RETENTION AND RECHARGE BASINS SOILS FROM URBAN RUNOFF1

ABSTRACT: The accumulation of arsenic, nickel, copper, and lead in the soil profile was determined beneath five urban storm-water retention/recharge basins used by the Fresno Metropolitan Flood Control District, California. Soils were sampled from the surface to the first zone of saturation and compared with soils from an adjacent un-contaminated control site. These elements were found to be accumulating in the first few centimeters of basin soil and are important to the effectiveness of a specific best management practice, i.e., the retention and recharge of urban storm water. Study basins in use since 1962, 1965, and 1969 had lead contents in the 0–2 cm soil depth interval‘of 570, 670, and 1400 mg Pb/kg soil, respectively. The median indigenous soil lead concentration was 4.6 mg/kg soil. The practice of removing excess flood runoff water from two basins by pumping apparently is a factor in reducing the accumulation rate of these elements in the surface soils of the basins.     

Management of Urban Road Runoff Containing PAHs: Probabilistic Modeling and Its Application in Beijing,China1

Abstract: Pollutant loading from storm runoff is considered to be an important component of nonpoint source pollution in urban areas. In developing countries, because of the accelerated urbanization and motorization, storm runoff pollution has become a challenge for improving aquatic environmental quality. An effective storm runoff management plan needs to be developed, and questions concerning how much and which proportion of a storm should be treated need to be answered. In this study, a model is developed to determine the fraction of storm runoff that needs to be treated to meet the discharge standard within a given probability. The model considers that the pollutants can be mobilized during the early stage of a storm. The model is applied to a field study of polycyclic aromatic hydrocarbons (PAHs) in road runoff in Beijing, China. In this case, the probability that the PAH load will be mobilized with suspended sediments by the earlier portion of the flush is 73%. Given the high PAH loading in the study area and the referenced discharge standard, the probability that the entire runoff should be captured and treated is 94%. Thus, urban planners need to consider treatment systems for the majority of the storms in this area, whether the PAH load is in the first flush or not. This methodology can be applied to other regions where PAH loads may result in different management outcomes.     

CALIBRATION OF STORM LOADS IN THE SOUTH PRONG WATERSHED,FLORIDA, USING BASINS/HSPF1

ABSTRACT: The South Prong watershed is a major tributary system of the Sebastian River and adjacent Indian River Lagoon. Continued urbanization of the Sebastian River drainage basin and other watersheds of the Indian River Lagoon is expected to increase runoff and nonpoint source pollutant loads. The St. Johns River Water Management District developed watershed simulation models to estimate potential impacts on the ecological systems of receiving waters and to assist planners in devising strategies to prevent further degradation of water resources. In the South Prong system, a storm water sampling program was carried out to calibrate the water quality components of the watershed model for total suspended solids (TSS), total phosphorous (TP), and total nitrogen (TN). During the period of May to November 1999, water quality and flow data were collected at three locations within the watershed. Two of the sampling stations were located at the downstream end of major watercourses. The third station was located at the watershed outlet. Five storm events were sampled and measured at each station. Sampling was conducted at appropriate intervals to represent the rising limb, peak, and recession limb of each storm event. The simulations were handled by HSPF (Hydrologic Simulation Program‐Fortran). Results include calibration of the hydrology and calibration of the individual storm loads. The hydrologic calibration was continuous over the period 1994 through 1999. Simulated storm runoff, storm loads, and event mean concentrations were compared with their corresponding observed values. The hydrologic calibration showed good results. The outcome of the individual storm calibrations was mixed. Overall, however, the simulated storm loads agreed reasonably well with measured loads for a majority of the storms.     

事故状态下污染物排放对水环境影响的预测研究

对辽河油田欢喜岭采油厂在事故状态下污染物排放对大凌河水域环境的影响进行预测研究。计算了洪水淹没、油罐冒顶泄漏、油井井喷泄漏、联合站泄漏、管道泄漏、暴雨径流带走落地油等16种情景下对该河流水质的影响情况,并建立数学模型,进行情景模拟。研究结果表明,事故状态下对大凌河水质影响的次序由大到小依次为:洪水淹没、油罐冒顶泄漏、油井井喷泄漏、联合站泄漏、管道泄漏、暴雨径流。     

DESIGN OF A DIVERSION SYSTEM TO MANAGE THE FIRST FLUSH1

ABSTRACT: To manage the first flush of storm runoff in urbanized areas, a diversion box and detention basin system has been proposed for a new storm sewer system or for retrofitting an existing system. A software package for a personal computer has been developed to facilitate the analysis and design of the system. Hydrographs and pollutographs are generated at the inlet and outlet of the diversion box and the detention basin. The peak outflow and peak pollutant concentrations are compared with the allowable outflow and pollutant concentration for urban stormwater quantity and quality management. The model is developed for both analysis and design purposes.     

A STORM WATER MANAGEMENT MODEL FOR URBAN AREAS IN KUWAIT1

ABSTRACT: A comprehensive study was conducted to implement the Storm Water Management Model (SWMM) for urban areas in Kuwait. The updated version of the model designed to run on an IBM Personal Computer and compatibles (PCSWMM3.2C) was utilized. The study revealed that urban runoff simulation in arid areas by the SWMM model is a powerful and efficient tool in designing drainage systems and as such, a viable replacement of the commonly used rational method. It was found that only the streets and paved areas that are hydraulically connected to the drainage system contribute to runoff. Fine and coarse discretization approaches were used in the study. The difference between the hydrographs simulated by the two approaches were relatively small. The performance of the existing drainage system and the accuracy of the design method used were tested using a 25-year storm. The result of the simulation revealed that the storm sewers were oversized by factors ranging from 1.2 to 3.6. The SWMM model was used to estimate the storm water runoff volume collected from all urbanized areas in Kuwait City. The annual expected harvested runoff water was found to be significant; however, the quality of runoff water needs to be assessed before a decision is made on its reuse.     

流域比较视角的钱塘江与黑河流域水资源问题及对策研究——基于水足迹核算分析

产品贸易及水权交易使得水资源问题"跨流域化",不再单纯是流域内部管理问题。本文从流域比较视角出发,在区分蓝、绿、灰三种水足迹的基础上,应用水足迹模型,测算了两流域典型地区的水足迹,进行流域水资源问题对比分析,并分析了经济发展模式对流域水资源可持续性的影响。结果发现,杭州市经济用水中灰色水足迹占总量的90%,而张掖市经济用水中绿色水足迹占总量的60.8%,说明钱塘江流域水资源问题在于质,而黑河流域水资源问题在于量;经济发展模式中的产业结构、水资源开发效率、工业化路径等影响流域水资源可持续利用,同时基于GDP导向的流域间的水资源逆向配置,更加剧了流域水资源矛盾。最后根据流域对比结果提出治理措施,从而形成流域间协作的良性循环。     

WATER RESOURCES MODELING AND OPTIMIZATION BASED ON CONSERVATION AND FLOODING POOLS1

ABSTRACT: A new and practical concept in water resources modeling and optimization is introduced. Instead of unrealistically assuming a multipurpose reservoir to be composed of a single lumped pool of water, it is treated as two different pools namely conservation and flood pools. Based on this treatment, the optimization problem is stated using the concepts of Lagrange multipliers and parameter optimization. The optimization problem consists of the material balance equation, the constraints on control and state variables and the objective function.