城市雨水景观设施的建设与改造

从水资源的匮乏和恶化出发,分析雨水回收利用的必要性和可行性;提出了以原有的自然水脉为网络进行城市规划以及建设和改造城市雨水景观的理念;利用城市原有的水系进行雨水和生活用水的收集,通过街道绿地中的水道,借助地势,将城市各区域的水汇集到城市低处的公园内进行统一的净化、协调,使城市雨水得以高效率的回收;并以山东即墨新城规划为例,从城市绿地系统规划的角度出发,以居住区、街道、公园等典型区域为例,为整个城市的水回收净化的景观设施设计提供了建议。     

城镇排水系统设计与运行中的若干问题探讨

按照传统规范设计的排水系统,在实际运行中存在很多问题,不便于维护管理。为此对雨水系统设计运行中的以下内容提出了改进措施:雨水口和淹没出水口的设置,在适当位置铺设雨水系统的连通管,积水严重段临时增设直通污水检查井的雨水口,合理铺设住宅区雨水系统、加快雨洪资源利用的推广应用等。另外,还对污水系统中的以下内容提出了改进措施:设计运行改进检查井构造,在适当位置铺设污水管系统之间的连通管,铺设污水厂进水总管复线,闸槽井做法,旧泵站集水池有效容积和最低水位线的确定,污水厂的规模和效率,排水体制的确定等,可供相关人员参考。     

Conceptual framework for decentralized green water‐infrastructure systems

We present a model for a decentralized green water‐infrastructure system (DGWIS) based on a new conceptual framework that optimises the use of captured rainwater, recycled wastewater and renewable energy resources. DGWIS is designed for building‐scale localised water supply systems that utilise rainwater and greywater and incorporate advanced small‐scale water treatment systems and renewable local energy sources such as solar and wind. Several constraints are considered: (i) available renewable energy; (ii) greywater production rate; (iii) potential captured rainwater; (iv) water demand; (v) water storage volumes required to accommodate greywater, harvested rainwater and separate water/energy supplies from the city and (vi) water treatment capacities. The proposed DGWIS optimisation framework demonstrates proof‐of‐concept and provides a solid foundation for an innovative paradigm shift towards water and energy sustainability.     

Rainwater harvesting for human consumption and livelihood improvement in rural Nepal: benefits and risks

Use of rooftop rainwater as a source of drinking water in developing countries is increasing. However, scepticism about the potential of this source and the associated health risks is still prevalent among water planners. A free listing and a household survey among 120 households was conducted in the hills of Nepal to examine the performance of rainwater harvesting systems. Users perceive few health risks and in contrast, reported a wide range of benefits, including health benefits associated with the consumption of rainwater. Water quality testing results generally demonstrate good water quality but confirm that appropriate operation and maintenance practices are critical to ensure the collection of good quality water. Deficiencies in technical design and construction, lack of awareness, no market for spare parts and the inability of vulnerable households to maintain the system pose a risk to the collection and storage of safe water and to the long‐lasting performance of the systems.     

Potential for potable water savings by combining the use of rainwater and greywater in houses in southern Brazil

Research on rainwater and greywater have been performed all over the world as a way of promoting potable water savings. The main objective of this article is to evaluate the potential for potable water savings by using rainwater and greywater in two houses in southern Brazil. An economic analysis is performed to evaluate the benefits of using rainwater and greywater either separately or together. Results indicate that the potential for potable water savings in both houses range from 33.8% (house B) to 36.6% (house A), considering that water for toilet flushing and washing machine does not need to be potable. By using rainwater, the potable water savings in house A would be 35.5% and in house B, 33.6%. When greywater is considered alone, potable water savings are lower, i.e., 30.4% in house A and 25.6% in house B. As for the use of rainwater and greywater combined, the potable water savings are 36.4% in house A and 33.8% in house B. The three systems that were investigated seem not to be cost effective as the payback periods were very high (above 17 years), but the greywater system was the most attractive one. The main conclusion that can be made from the research is that there needs to be government incentives in order to promote the use of rainwater or greywater in houses in southern Brazil.     

Rainwater utilisation in Germany: efficiency,dimensioning, hydraulic and environmental aspects

In this study, the development and performance of rainwater utilisation systems in Germany are described. Initially the operational characteristics of the different types of rainwater utilisation systems are explained. The objective of the modelling-based investigations is to quantify the effects of rainwater usage systems on the urban drainage system. On the basis of a long-term simulation of 10 years rain data, the following parameters were calculated: tank volumes, covering efficiency, drinking water savings, overflow occurrence, overflow volumes, overflow reduction, recurrence time of overflows. The water balance of a one-family house and a multi-storey building in Bochum was calculated in a case study.     

Potential for potable water savings by using rainwater and greywater in a multi-storey residential building in southern Brazil

Studies on the use of rainwater and greywater to promote potable water savings have been performed in different countries. The main objective of this article is to evaluate the potential for potable water savings by using rainwater and greywater in a multi-storey residential building composed of three blocks, located in Florianópolis, southern Brazil. Water end-uses were estimated by applying questionnaires and measuring water flow rates. An economic analysis was performed to evaluate the cost effectiveness of using rainwater and greywater either separately or together. Results show that the average potential for potable water savings range from 39.2% to 42.7% amongst the three blocks, considering that water for toilet flushing, clothes washing and cleaning does not need to be potable. By using rainwater, the potable water savings would actually range from 14.7% to 17.7%. When greywater is considered alone, potable water savings are higher, i.e., ranging from 28.7% to 34.8%. As for the use of rainwater and greywater combined, the potable water savings range from 36.7% to 42.0%. The main conclusion that can be made from the research is that the three systems that were investigated are cost effective as the payback periods were lower than 8 years, but the greywater system was the most cost effective one, followed closely by the rainwater one.     

Assessing integrated water management options for urban developments – Canberra case study

Urban water services in the Australian Capital Territory (ACT) are currently provided through conventional centralised systems, involving large-scale water distribution, wastewater collection, water and wastewater treatment. A study was conducted to assist Environment ACT in setting broad policies for future water services in Canberra. The current paper presents the outcomes of a study examining the effects of various water servicing options on water resources and the environment, for two townships in Canberra, one existing and one greenfield site. Three modelling tools were used to predict the effects of various alternative water servicing scenarios, including demand management options, rainwater tanks, greywater use, on-site detention tanks, gross pollutant traps, swales and ponds. The results show that potable water reductions are best achieved by demand management tools or a combination of greywater and rainwater use for existing suburbs, while third pipe systems are preferred for greenfield sites. For this specific climatic region and end use demands, modelling predicted increased water savings from raintanks compared to greywater systems alone, with raintanks providing the additional benefit of reduced peak stormwater flows at the allotment scale. Rainwater and stormwater reuse from stormwater ponds within the catchments was found to provide the highest reduction in nutrient discharge from the case study areas. Environment ACT amended planning controls to facilitate installation of raintanks and greywater systems, and commenced a Government funded rebate scheme for raintanks as a result of this study.     

住宅小区雨水回收利用方法探讨

随着可利用水资源的日趋紧张,雨水以其处理成本低廉,处理方法简单等优点,而成为一种新的可利用水资源。文章从建筑小区雨水利用系统的概念入手,简单介绍了目前国内外几种主要的雨水利用系统,并指出加大建筑小区雨水利用对我国具有重大意义。     

Rainwater tank capacity and potential for potable water savings by using rainwater in the residential sector of southeastern Brazil

Rainwater has been used in many countries as a way of minimising water availability problems. In Brazil, it has been reported that the potential for potable water savings by using rainwater may range from 48% to 100% depending on the geographic region. In southeastern Brazil, water availability is about 4500 m³ per capita per year, but it is predicted to be lower than 1000 m³ per capita per year from about 2100 onwards. The main objective of this article is to evaluate the potential for potable water savings by using rainwater in 195 cities located in southeastern Brazil. Rainwater tank sizes are also assessed for some cities in order to evaluate the ideal tank capacity as a function of potable water demand and rainwater demand. Results indicate that average potential for potable water savings range from 12% to 79% per year for the cities analysed. Ideal rainwater tank capacities for dwellings with low potable water demand range from about 2000 to 20,000 litres depending on rainwater demand. For dwellings with high potable water demand, ideal rainwater tank capacities range from about 3000 to 7000 litres. The main conclusion drawn from the research is that the average potential for potable water savings in southeastern Brazil is 41%. It was also concluded that rainwater tank capacity has to be determined for each location and dwelling as it depends strongly on potable water demand and rainwater demand.     

The use of rainwater for WC flushing: the field testing of a collection system

The flushing of toilets with rainwater collected from roofs makes a significant saving in the use of potable water. This paper describes some of the results from field testing a rainwater collector installed in a U.K. house. The capacity of the storage tank is critical in the design of such systems. The data collected was used to verify and refine a rainwater collector sizing model. The model was used to produce a set of dimensionless design curves which enables the storage capacity required to achieve a desired performance level to be easily determined if the roof area and demand patterns are known.     

青岛市鲁信长春花园雨水利用工程设计与运行

青岛市鲁信长春花园利用小区汇集雨水及部分浮山泄洪雨水,因地制宜将雨水利用应用于小区景观工程。在产生径流一段时间后,径流雨水水质趋于稳定,COD为100～200 mg/L,SS为500～1 000 mg/L,采用沉淀过滤/人工生态净化组合工艺,处理后人工湖水体水质符合《城市污水再生利用景观环境用水水质》(GB/T 18921—2002)中观赏性景观环境用水水质相应标准。工程运行2年以来,运行效果良好,社会效益、经济效益和环境效益显著。     

城市雨水收集与利用研究

论述了城市雨水收集与利用的必要性,提出了城市雨水资源收集的方式有建造贮留设施、就地下渗、建立即时水库和绿地隐形蓄水系统四种,并指出其利用途径有作为生活杂用水、工业用水、绿地灌溉、补充河湖用水以及雨水回灌等。     

蓄水陶土对雨水面源污染物的吸附性能研究

以新型城市雨水蓄水材料——蓄水陶土作为吸附介质,研究其对武汉城市主干道雨水面源污染物的吸附、截留及净化雨水的效果。结果表明：蓄水陶土对SS的去除率〉50%,对COD的最高去除率为53.8%,对TP的平均去除率为43.2%,对TN的平均去除率为42.5%。蓄水陶土作为一种新型环保材料,可以广泛地应用于城市雨水面源污染的治理工程之中。     

Potential of rainwater resources based on urban and social aspects in Colombia

The potential offered by non‐conventional water resources (rainwater) associated with high or low urban density in new housing in different rainfall zones (800–2300 mm) was studied. Ten cities in Colombia with over 250 000 inhabitants were used as a case study. The potential of substitution of tap water by rainwater according to population groups with different socioeconomic status was estimated. This study reveals the favourable conditions for rainwater harvesting in the Colombian context, and enables the linking of supply and demand issues related to local climatic and environmental sustainability in order to integrate the use of rainwater into urban housing projects. For the current consumption scenario (greater than 160 Lcd), rainwater becomes a potential replacement for mains water in urban areas with rainfall of above 1553 L/m²/year.     

The effect of roofing material on the quality of harvested rainwater

Due to decreases in the availability and quality of traditional water resources, harvested rainwater is increasingly used for potable and non-potable purposes. In this study, we examined the effect of conventional roofing materials (i.e., asphalt fiberglass shingle, Galvalume^® metal, and concrete tile) and alternative roofing materials (i.e., cool and green) on the quality of harvested rainwater. Results from pilot-scale and full-scale roofs demonstrated that rainwater harvested from any of these roofing materials would require treatment if the consumer wanted to meet United States Environmental Protection Agency primary and secondary drinking water standards or non-potable water reuse guidelines; at a minimum, first-flush diversion, filtration, and disinfection are recommended. Metal roofs are commonly recommended for rainwater harvesting applications, and this study showed that rainwater harvested from metal roofs tends to have lower concentrations of fecal indicator bacteria as compared to other roofing materials. However, concrete tile and cool roofs produced harvested rainwater quality similar to that from the metal roofs, indicating that these roofing materials also are suitable for rainwater harvesting applications. Although the shingle and green roofs produced water quality comparable in many respects to that from the other roofing materials, their dissolved organic carbon concentrations were very high (approximately one order of magnitude higher than what is typical for a finished drinking water in the United States), which might lead to high concentrations of disinfection byproducts after chlorination. Furthermore the concentrations of some metals (e.g., arsenic) in rainwater harvested from the green roof suggest that the quality of commercial growing media should be carefully examined if the harvested rainwater is being considered for domestic use. Hence, roofing material is an important consideration when designing a rainwater catchment.     

居住小区景观水体两种雨水补给方式的比较研究

以上海市W居住小区和G居住小区为例,分别调查研究了利用屋面径流与经植草沟输送净化的地表径流用作补充景观水体的使用效果.结果表明,TP含量较低的屋面径流作为小区景观水体的补充水是可行的,具有良好的应用效果;而在人口密度高、水体面积小的居住小区,采用经植草沟和植草缓冲带拦截净化的地表径流作为景观补水的做法需慎重选择.     

东莞某学院雨水利用及景观水体系统综合解决方案

本文以东莞某学院为例进行雨水收集利用和中心景观水系统的方案设计。为保证湖水水质,需要对景观水进行循环处理,防止水体富营养化的发生。通过雨水利用、景观湖防渗处理等措施,减少景观水体的补充水量。富余雨水则用于学院内的绿化给水。     

Analysis of a rainwater collection system for domestic water supply in Ringdansen,Norrköping,Sweden

The possibilities for implementing a rainwater collection system in Ringdansen, a residential area in Norrköping, Sweden, have been explored by analysing four scenarios for using rainwater in a dual water supply system to supplement drinking water. A computer model has been generated to quantify the water saving potential of the rainwater collection scheme. The performance of the rainwater system is described by its water saving efficiency (WSE). Standard and low water consumption appliances have been taken into account in evaluating WSE and water conservation. According to the analysis, suggested rainwater tank sizes are presented.     

The collection of rainwater from dome stadiums in Japan

In 1998, the Ministry of Construction began to investigate rainwater utilization facilities throughout Japan, as part of a wider program of preserving the urban hydrological cycle. As a result, there has been increased recognition that it is important to utilize rainwater for the purpose of effective urban water control and water conservation. Under these circumstances, there will be more construction of rainwater utilization facilities. This paper describes the inspection of rainwater utilization at dome stadiums, which Takenaka Corporation have designed and constructed during the past 10 years in Japan. The dome stadium is a large-scale structure, where baseball games, concerts and various exhibitions are held. A large volume of water supply is needed at one time. Therefore, it is wise to utilize rainwater for the purpose of saving water supplies from a view of water resources in urban areas. Moreover, from the viewpoint of preserving the water environment and runoff control in urban areas, it is important to utilize rainwater. This paper states social background of construction, the outline, design methods, effects and views on the future of all dome stadiums.