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21.
南京市雨污分流改造经过多年建设施工,基本上从源头上实现雨污分流,避免污水溢流入秦淮河。初期雨水造成的城市非点源污染是受纳水体的重要污染源,在一些实施了分流制排水系统的城市,经过一段时间的运行,周边水体的污染情况改善不是十分明显。白下区雨污分流改造后,为避免初期雨水对内秦淮河污染,以大中桥泵站北截流沟为例,探讨在沿河截流井设提升泵弃流初期雨水,利用现状截流沟蓄水,结合规划改造大中桥泵站新建蓄水池,为今后雨水利用提供条件。  相似文献   
22.
为解决中小城市污水排水问题,进一步加强城市排水管理,改善城市水环境,杜绝雨污混排,提高污水处理率,分析和探讨了中小城市在污水排水系统建设、管理、维护中存在的问题,针对排水法规不健全、污水管网不完善、雨污分流难、管理不到位等问题进行原因分析,提出加强排水制度建设、加快排水设施的建设、加强排水管理、加强宣传教育等措施.  相似文献   
23.
ABSTRACT: The development of a regional water supply system for the six-county area of Northeastern Illinois is presented in this paper, including: 1) the establishment of regional water supply technical planning policies; 2) the development and utilization of a regional water supply computer model to identify the principal and secondary sources of water supply for each entity in the study area, based on an apparent cost-effective source analysis; and 3) utilization of the study results to develop for the year 2010 a suggested preliminary regional water supply system. Using the findings from task 2 above, a proposed plan for overall Lake Michigan water use through the year 2010 was also developed. The effects of the proposed regional water supply system on future water levels in the deep aquifer were also discussed.  相似文献   
24.
分洪区数字地形模型建立及其应用   总被引:4,自引:0,他引:4  
张健挺  陈德清 《灾害学》1998,13(1):7-10
从实用的角度介绍了建立分洪区数字地形模型(DTM)方程,并给出了在分洪区信息可视化、分洪区特征曲线生成、分洪区二维洪水演进等等方面的应用。  相似文献   
25.
A diversion system has been designed to carry the flow from East Fork of Coal Creek around the area proposed for mining at Thunder Basin Coal Company's (TBCC) Coal Creek mine in Campbell County, Wyoming. This paper describes the field and analysis procedures necessary to prepare the diversion design and impact evaluation, and the innovative concepts developed for the diversion system design to minimize impacts on downstream channel stability. Under the proposed diversion system design, water from the East Basin of Coal Creek will be diverted at two locations. At one location, flow will be impounded by a small dam and decanted by a pump through a pipeline into East Fork at the location of the second diversion. At this location, a training dike will be placed across the stream channel to divert flows into a diversion channel. Gravity flow along the diversion channel will deliver water to a playa area which will be converted into a detention basin by placing a small dam across its southern end. Flows up to the magnitude of the 24-hour 2-year peak flow will be passed directly through the detention basin into Middle Fork with negligible attenuation of flow rates. For less frequent events, water will be stored in the detention basin in order to prevent velocities in Lower Middle Fork from exceeding the maximum permissible velocity above which scouring may occur. Evaporation and seepage losses from the diversion system were estimated to be small and should be more than offset by the addition of water from the playa drainage basin into the Coal Creek drainage. Velocities predicted for the Lower Middle Fork after-the diversion is constructed are expected to be low enough that significant erosion of the channel is not expected to occur.  相似文献   
26.
ABSTRACT: Grain transportation is a major economic activity on the multiple use Snake-Columbia River System. Congress is currently considering increased transportation user fees aimed at recapturing federal expenditures for waterway operations and maintenance. Three types of fee structure and four levels of cost recovery are evaluated using a network program model. In each case traffic is diverted away from the river to other Puget Sound ports via truck and rail transport modes. Grain shippers in the region will be adversely affected by a higher transport bill. The Lower Columbia River port economic activities will be negatively affected; however, competitive uses of the river, recreation, and hydroelectric generation will likely benefit modestly.  相似文献   
27.
As biodegradable material represents approximately 70% of household waste in Brazil, any strategy to divert appreciable waste quantities from landfills of necessity has to include valorization and recycling of this material. A societal change of attitude is required to perceive this challenge. Experiments in an urban apartment building are described that produced this change of attitude with a success factor of 80%. Divided waste collection was implemented that separated at the source biodegradable from inert material. Correct collection, handling and display procedures were established. Composting of biodegradable material was carried out under the rooftop of the building as an alternative to using it as animal feed. Half of the inert material entered the reverse logistics chain and was also diverted from the landfill. Waste related material flow through the building is completely quantified, food intake and waste production are related, diversion of both biodegradable and inert waste components from the landfill is measured and the composting process is described. The landfill diversion stands at 61%, mass reduction through the composting process is 80% and matured compost is returned to residents for use in flower cages. The system has been operational for two years and stands out as a precedent in successful decentralized household waste management supported by material flow analysis. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
28.
引水调控改善太湖湖湾水环境及其效果预测   总被引:6,自引:0,他引:6  
在总结太湖水污染问题的基础上,分析得出水流缓慢、动力掺混能力弱、水流交换不畅、水体自净能力差、纳污能力小、入湖污染负荷量大且远超过湖湾的纳污能力是梅梁湖湾水污染严重的主要原因,提出区域水污染综合治理、入湖污染物总量控制、引水调控等水污染防治策略及其关键控制技术,利用数值模拟技术给出了太湖梅梁湖湾入湖污染物排放总量控制定额,并结合引江济太调水试验,采用平面二维水流水质数学模型模拟预测引水调控对梅梁湖湾的水环境改善效果及大流量集中调水和小流量维持性调水的水环境  相似文献   
29.
Summary Present municipal waste management paradigms in Brazil do not allow for flexible approaches to solving an extremely dynamic problem. This paper discusses the basic flaws in present thinking models of residents and municipal administrators. Fundamental arguments presented on municipal solid waste relate to nomenclature, destinations, definitions, logistics, social dynamics, social assistance programs, education and employment philosophies. In each case, the consequences of the stalemate are explained in terms of the unsustainable situation of constantly growing landfills. In sequence, a proactive thinking model is presented and explained that has the potential of drastically reducing landfill size. It is called Municipal Transit Material Processing. The model has been tested successfully in small communities and is now available for scale-up. The landfill diversion achieved stands at 62% of household waste in comparison with 15% theoretically possible in Brazil with selective collection models. Although of necessity the arguments apply directly to Brazil, the basic ideas behind the reasoning may be extrapolated to other Southern countries. The following simple example will illustrate to the reader the type of paradigm inversion the paper proposes to convey. The classical political slogan in Brazil is “get children out of garbage dumps”. The inversion proposed and explained is “do away with garbage dumps”.  相似文献   
30.
由于水资源分布不均、水污染日趋严重,调水工程已不仅用以解决城市资源型缺水,也成为一些地区缓解水质型缺水问题的途径,但是这些耗资巨大的调水工程往往对周围自然生态环境可能产生巨大影响,可能带来的环境成本不容忽视。以千岛湖配水工程为例,通过在调水地进行实地调研和问卷调查,运用Tobit模型分析影响居民支付意愿的因素,基于意愿调查法(CVM)分析了建德市人民对千岛湖配水工程的生态环境影响的支付意愿,并以此估算该工程的环境成本。结果表明,调水地居民对恢复和改善可能破坏的生态环境的平均支付意愿约为每人每年377.6~542.1元,按照年配水量9.78亿 m3可以计算每吨水的环境成本约为0.15~0.21元。由此估算,工程期内千岛湖配水工程可能造成的环境成本总计约为5.80~8.28亿元,高于2014年公布的《杭州市第二水源千岛湖配水工程环境影响报告书》(下文简称《报告书》)中对该工程的环境经济影响评价3.70亿元。千岛湖配水工程的环境成本不容忽视,必须建立科学的生态补偿机制,加强监管;同时受水地也应积极加强污染治理和节约用水,共同解决城市水质型缺水问题。  相似文献   
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