Coagulation of micro-polluted Pearl River water with IPF-PACls

Water samples collected from early March 2001 to the end of April 2002 at the branch of Pearl River around the Guangzhou City were analyzed for its micro-polluted characteristics. The coagulation behavior of polyaluminum chlorides(PACls) was then examined focusing on the effect of primary water quality and speciation distribution. The results showed that PACls exhibit better coagulation efficiency than alum in accordance with the different speciation. The turbidity removal property of PACls is evidently better than alum at low dosage. While in neutral zone(about 6.5—7.5), the turbidity removal of PACls decreases owing to the restabilization of particles at higher dosage. The organic matters in raw water exhibit marked influence on coagulation. In acidic zone, organic matters complex with polymer species and promote the formation of flocs. With an increase in pH, the complexation of organics with polymer species gradually decreases, and the removal of organics mainly depends on adsorption. The effect is evidently improved with the raise of B value.

Preparation of New Poly Silicate Iron Coagulants and Their Coagulation Property on Micro-polluted Water

The sodium silicate, ferric chloride, ferrous sulfate, sodium chlorate and other common inorganic materials were used to synthesize two new poly silicate iron coagulants： Polysilicate Ferric Chloride （PFSiC） and Polymeric Ferric Silicate Sulfate （PFSiS）. Their coagulation effect on micro-polluted water was compared with the poly ferric choride （PFC） saled in the market. The results showed that turbidity, organic matter, total phosphorus, total nitrogen removal rate ofPFSiC, PFSiS coagulant were better than PFC on micro-polluted water treatment at the same dosage. The coagulation effect of PFSiC was the best. The surface morphology of three coagulants was observed by scanning electron microscopy （SEM）, and the coagulation mechanism was discussed preliminarily.

Performance of BAC process for treatment of micro-polluted water

Biological activated carbon (BAC) has been developed on the granular activated carbon by immobilization of selected and acclimated species of bacteria to treat the micro-polluted water. The BAC removal efficiencies for nitrobenzene, permanganate index, turbidity and ammonia were investigated. Effects of shock loading and SEM (Scanning Electron Microscope) observation on BAC were studied. Backwashing and its intensity of BAC were also discussed. The results showed that BAC took short time to start up and recover to the normal condition after shock loading. The shock loading studies showed that the removal efficiency of BAC was not completely inhibited even at high concentration of nitrobenzene. Backwashing performed once every 10-20 d, or an average of 15 d. Backwashing intensity was 12-14 L/(s·m2) with air and 3-4 L/(s·m2) with water.

The Occurrence and Prevention of Filamentous Algae in Ecological Purification System of Micro-polluted Water

[ Objective ] The aim was to study the influence of filamentous algae on the process of water ecological purification. [ Method ] The occurrence mechanism of filamentous algae and its ecological system were summarized and analyzed. Considering the ecological purification in north- ern Jiangsu, the occurrence and prevention of filamentous algae in water, the method to prevent filamentous algae in polluted water was discussed. [ Result] The results showed that by measures of improving planting density, regular harvesting, and water flow state control before the filamentous algae blooming period, together with improving local pH value, light interference and ecological control during the blooming period, can effectively control the filamentous algae blooming. [ Condusion] The study of the happening mechanism of filamentous algae provided theoretical references and the technical basis in the work of filamentous algae prevention and control.

Surface flow constructed wetland with composite plant bed for pretreatment of micro-polluted Yellow River raw water in China

In order to investigate the feasibility of pretreating the micro-polluted Yellow River raw water by constructed wetland, an experiment was conducted using a surface flow constructed wetland with composite plant bed. The contamination removal efficiency and their trends in the wetland treatment system were studied under different hydraulic loading rates(HLR). The contamination removal efficiencies were compared according to the seasonal change under optimum HLR. The result shows that in the same season, under different hydraulic loadings ranging from 2 to 6 m3/(m2·d) at the same period, the best HLR is 4 m3/(m2·d) in the experimental system. The average removal rates of COD, TN, ammoniacal nitrogen(NH4+-N), and TP in the constructed wetland are 38.37%, 45.97%, 39.86% and 41.69%, respectively. According to China Standard for Surface Water Resources (GB3838-2002), mean effluent of COD, TN, NH4+-N and TP can nearly reach Grade Ⅲ, GradeⅤ, GradeⅠand GradeⅠ, respectively. Furthermore, treatment efficiency of the system in summer is obvious higher than that in other seasons. The expenditure of constructing the constructed wetland with the average treating capacity of 176 m3/d and lifetime of 20 years is 17075.00 RMB. The average disposal cost is summed up to 0.17 RMB/m3, which shows that the pretreatment of the micro-polluted Yellow River raw water by constructed wetland is feasible.

Oil Pollutants Degradation of Nano-MgO in Micro-Polluted Water

The removal of oil pollutants from water and purifying process of oil-polluted water are studied through catalytic degradation method with nano-MgO. The results indicated that catalytic degradation effect of nano-MgO on the oil pollutants was associated with dosage of nano-MgO, pH and water temperature. When oil content was 1.8 mg/L, 0.17 g nano-MgO was used and the removal rate of oil was 93.92%. Furthermore, nano-Mgo was a non-photosensitive catalyst. GC/MS analysis showed that the amount of petroleum-based pollutants in water was reduced 73.77% from the previous 61 kinds to 16 kinds, and the total peak area was reduced 96.05% after catalytic degradation of nano-MgO. Therefore, nano-MgO has an excellent effect on the catalytic degradation of oil pollutants and can be applied in the treatment of oil wastewaters.

Water Pollution Situation and Impacts in Rural China

With the development of national economics, water pollution is becoming a critical problem in rural China. This research presented a brief view of water pollution situation in rural areas of China in terms of water shortage, water-pollutant sources, eutrophication of water bodies and pollution development in temporal scale. Analysis was conducted on the negative effects of water pollution on human health, agricultural plantation and animal husbandry. Subsequently, some suggestions were proposed for wastewater treatment in rural areas.

Health Risk Assessment on Rural Drinking Water Safety —A Case Study in Rain City District of Ya’an City of Sichuan Province

Taking Rain City District of Ya’an for example, this paper based on ComGIS (Component Object Model Geographic Information System) platform takes comprehensive and systematic detection on the exposure dose of chemical carcinogens and non-carcinogens from drinking water sources in this region and discusses health risk assessment of single factor and the whole health risk assessment. As, Hg, Cr, Pb, Cd and fluorides in some drinking water sources of Rain City District are analyzed according to Standards For Drinking Wa-ter Quality (GB5749-2006). A health risk assessment model called USEPA is also applied to drinking water health risk assessment and management countermeasure is proposed. The results show that the greatest health risk for individual person per year is caused by Cr(VI). The health risk of carcinogens is much higher than that of non-carcinogens: the greatest risk value due to non-carcinogen pollutants is caused by fluoride (F), achieving 1.05×10-8/a. The ranking of risk values due to non-carcinogen pollutants by drinking water is Pb>fluoride (F)>Hg, within Pb accounting for 44.77%, fluo-ride (F) accounting for 34.30% and Hg accounting for 20.92%. The average individual carcinogenesis annual risk of Cr(VI) is the greatest, achieving 8.91×10-4/a. The ranking of risk value due to chemical carcinogen by rural drinking water of Ya’an is Cr6+>As>Cd, within Cr6+ accounting for 91.12%, As accounting for 5.89% and Cd accounting for 3.00%. Based on this, the strategy and measures of the health risk management are put forward. This study has worked efficiently in practice. Compared with the same kind of methods which have been found, the paper has the outstanding results for the health risk assessment of the rural drinking water safety.

Human intestinal parasitism,potable water availability and methods of sewage disposal among nomadic Fulanis in Kuraje rural settlement of Zamfara state

Objective:To ascertain the level of intestinal parasites vis-a-vis the quality of housing and water supply,and sanitary conditions among the people of Kuraje village in Zamfara state. Methods:The study was cross sectional in nature.Individual households were selected using systematic random sampling methods and pre-tested questionnaires were administered to all the members of each household.Stool samples were collected and processed using standard laboratory procedures.Housing conditions,sources of water and sanitary conditions of the households were also inspected.Results were analysed using Epi Info 2006 model.Results: The prevalence of intestinal parasites was 67.0%(347/519).72.3%(251/347),17.0%(59/347),and 10.7%(37/347) had one,two and three or more parasites,respectively.The associated factors with intestinal parasites were poor housing and sanitary conditions,lack of potable water and illiteracy.The commonest parasites encountered were hookworm(22.0%),Ascaris lumbricoides (18.5%),and Strongyloides stercoralis(15.6%) while the least common was Enterobius vermicularis (1.6%).Others were Giardia lamblia(5.7%),Hymenolepsis nana(5.0%),Trichuris trichiura(8.8%), Entamoeba histolytica(14.4%) and Schistosoma mansoni(8.4%).Conclusions:The infection rate of intestinal parasites in Kuraje village is high.More efforts should be intensified towards improvement in sanitary and housing standards,supply of potable water and institution of a more comprehensive literacy programme for the people of the community.

Protection Planning for Rural Centralized Drinking Water Source Areas in Chongqing

Protection planning is made for rural centralized drinking water source areas according to current situations of rural drinking water and existing problems of centralized drinking water source areas in Chongqing,and in combination with survey,analysis and evaluation of urban-rural drinking water source areas in whole city.There are engineering measures and non-engineering measures,to guarantee drinking water security of rural residents,improve rural ecological environment,realize sustainable use of water resource,and promote sustainable development of society.Engineering measures include conservation and protection of water resource,ecological restoration,isolation,and comprehensive control of pointsource and area-source pollution.Non-engineering measures include construction of monitoring system for drinking water source area,construction of security information system for rural centralized drinking water source area,and construction of emergency mechanism for water pollution accidents in rural water source areas.

Comparison of Using an Electronic System and Conventional Monitoring Method for Monitoring the Quality of Drinking Water and Defects Discovery in Rural Area Water Distribution Network of Abarkouh, Iran

The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventional monitoring method (According to ISIR (Institute of Standards and Industrial Research of Iran), 1053 and 4208) and use of electronic system method (Patent in industrial property general office of Iran, 77815). Free chlorine monitoring and pH test done by health workers in the conventional method and the results will be sent to the Health Network monthly. Sampling for microbiological testing is done monthly based on population (According to ISIR, 4208). On the electronic system, the procedure is also done by health workers, but the result will be sent to the receiver device by using a cell phone. According to the chlorine test results if the free chlorine residual reported zero, microbiological sampling was done by a health expert. Finally, the number of chlorine test and microbiological sampling and the results of these experiments collected in the both methods and recorded in SPSS 22 then were analyzed by using chi-square test and Fisher exact test. The result of microbiological experiments shows that the sampling rate decreased 29% in using of electronic system method in comparison to the conventional monitoring method while the number of microbial defect detection increased 19% in drinking water networks monitoring by electronic system. Using of electronic system monitoring can reduce the rate and cost of microbiological sampling and its experiments and increase accuracy of these tests, in this way it will increase the quality and safety of drinking water in distribution network in small and dispersed rural communities.

Rural Water Supply Management and Sustainability: The Case of Adama Area, Ethiopia

Wise utilization of water resources is becoming very important as world faces water crises. The main objective of this study was to investigate the rural water supply systems with case study in Adama area, in central Ethiopia. Both quantitative and qualitative data were collected and analyzed. Four sample water schemes were selected and totally 148 (63 were female) representative households were selected for answering the questionnaires. Key informant interviews and group discussions were also conducted. The study assessed issues such as community participation, water committee empowerment, management and governance of water supply schemes, women participation, functional status of water supply scheme, sanitation and hygiene issues, external support, and monitoring system of water supply schemes. The findings indicated that the community participation in planning and implementation was very good while monitoring mechanism of operation and management as well as community participation on choice of technology was poor. The water schemes were located at reasonable distances i.e. less than 2 km in most cases and the time taken for round trip to fetch water from source was less than or equal to 30 minutes in most cases, however the queuing time was more than an hour. The water supply was inadequate as only about 15% of beneficiaries could get 20 liters of water per day per capita. The water sources were exposed in many cases to human waste, wild life, livestock and uncontrolled flooding. Sanitary practices in the study area were poor as only about 3.4% had ventilated and improved pit latrine and open pit and/or open field defecation were widely practiced.

ComGIS-Based Early Warning System of Rural Drinking Water Safety in Ya’an City of Sichuan, China

According to characteristic index of spatial-temporal variability of rural drinking water safety in Ya’an City of Sichuan, China, such as water quantity, water quality, convenience degree and guaranteed rate, etc., this study elaborated the basic framework, model’s methodology structure in early warning system of rural drinking water safety on the basis of ComGIS and initially designed information collection, search and re-trieval, evaluation and analysis of factors, dynamic prediction and dynamic early-warning and functions of guidance and management in this system. The design of this system provided scientific basis to grasp the state of rural drinking water safety timely, release early warning information and properly take necessary control measures, etc. The evaluation results showed that the overall trend was getting better. It proved that the rising pressure value and response value were main reasons which caused the rising evaluation value of rural drinking water safety.

Water Supply Dilemma in Nigerian Rural Communities: Looking Towards the Sky for an Answer

Access to safe water supply has great influence on the health, economic productivity and quality of life of the people. But meeting this need is one of the major challenges facing the rural communities of Nigeria today. The purpose of this review paper is to determine whether water supply have contributed effectively to health, social, and cultural development of Nigerian rural communities. Over 70% of households in rural communities do not have access to improved water supply. They rely solely on self-water supply (free source) such as rivers, perennial streams, water ponds and unprotected wells which is susceptible to water borne diseases such as typhoid fever, cholera, dysentery, malaria parasites etc. These rural populations are engaged in farming activities with low income level living in small scattered settlements thus, making provision of piped water supply very difficult. Governments’ interventions towards rural water supply have been through the provision of hand-operated boreholes and wells. These sources yield little or no water during the dry season and are prone to frequent breakdown;leading water crisis and shortages. This situation forces households especially the women and children to spend more time walking longer distances during the dry season to trot water for domestic purposes. Given the fact that the publicly operated water supply have not been able to cope with increasing demand, there is a need for a paradigm shift from the public monopoly of water supply to an innovative approach. Rainwater harvesting technology appears to be one of such alternative approaches.

Exploration of Near Water Rural Landscape Planning and Design:Taking Shiping Village,Zhijiang City in Hubei Province as an Example

By centering on the problems in rural environment and ecology in new rural planning of China,this study is to discuss the new rural planning modes through the effective methods on the near water rural landscape planning and design.Based on the studies of the status at home and abroad,borrowing ideas from successful cases,this study intends to apply the landscape ecological design technique to the Shiping Village,Zhijiang City in Hubei Province by depending on the near water geographical position and water resources.Through improving pools,fishponds,rivers,canals and other environments near water and planning and design of landscape,modern ecological new countryside with features of water resource is formed.Through discussion,we find effective ways to improve ecological environment of countryside,protect style and feature of countryside near water,construct people-oriented rural development system of and promote the construction of rural human habitat environment.Such landscape planning model of countryside near water obtains good ecological and environmental effect,and provides references for projects of similar themes.

Predicament and Countermeasures for the Management and Maintenance of Rural Water Conservancy Facilities

The major problem of rural water conservancy facilities during its management and maintenance is in the "been used, under no control" state. And the main reasons of this state are the public belonging property, investment by a single subject, and lack of effective supervision and management mechanism. Since rural water conservancy facilities is used in small scale and has the features of rural "acquaintances community", a balanced long-term interest mechanism for the management and maintenance of rural water conservancy facilities is established for interest-related parties. On short-term view, the most effective measure is to bring the operational status of rural water conservancy facilities into the evaluation indicators of the local government.

Current Situation and Countermeasures of Water Body Pollution in Rural Areas of China

At present, people＇s environmental awareness gradually enhances, and the environmental requirements on production and living continuously improve. Urban sewage discharge management and sewage treatment intensity are increasing in whole country, and urban water environment has certain improvement. But in rural areas, due to relatively weak environmental awareness of residents, not high economic development degree and not perfect infrastructure construction, the issue has not been handled properly. It seriously restricts further development of rural economy, and contradiction between water pollution worsening and farmers eager to raise the level of living environment increasingly aggravating has become key problem restricting China＇s new rural construction. According to status quo of rural water pollution in China, causes and hazards of rural water pollu- tion are analyzed in detail, and several treatment suggestions are put forward.

A Study on the Microbial Quality of Drinking Water in Rural Areas of Mazandaran Province in North of Iran (2011)

Backgrounds: One of the fundamental needs of a community is to have an access to healthy and safe drinking water. The lack of a concentrated accessibility to health facilities and services is among the serious problems facing villagers in the rural areas. The aims of this research was to investigate the drinking water quality of the villages in Babol township suburbs in north of Iran. Materials and Methods: In this cross-sectional descriptive study, a total of 140 water samples were taken from the water distribution network in16 villages for the low and high-rain seasons in sterile glass bottle. The microbial quality of gathered samples were determined based on standard methods in laboratory. Statistical analysis of the results was performed using a SPSS16 statistical software. Findings: Based on obtained results 13.6% of the samples were contaminated to coliform and 20% to fecal coliform bacteria. The residual chlorine in 12.5% of the samples were between 0.2 to 0.8 mg·L-1 and the PH in total samples were between 6.8 to 7.8. There were no signs of any contamination for 32.86% of the analysed samples which water resources is located to a distance of more than 30 m to the contamination sources. In addition, 43.1% of the samples taken from the water resources with no plumbing system, have had a fecal contamination. Conclusions: Considering the results achieved, the microbial quality of the drinking water of the studied villages classified as “moderate” status. For more water supply there is not sufficient residual chlorine in most cases. Poor sanitation of water supply is most causes of water contamination. It is therefore strongly recommended that sanitation measures are made to protect water resources from the contamination.

Design of Water Disinfection Scheme for Rural Drinking Water Safety Project

As further promotion of the rural drinking water safety project in whole country, small villages in vast countryside have been or will be equipped with safety drinking water project. We analyzed necessity of the rural drinking water disinfection, discussed disinfection method suitable for rural drinking water characteristics, and put forward disinfection schemes for different water supply sources.

Rural Water Access and Management Approaches in Southern Africa： Lessons from Namibia and South Africa

Water scarcity is a major problem for Namibia and South Africa as both countries are classified as ＂water stressed＂, based on their per capita water availability which is below the threshold of 1,000-1,666 ma-person^-1.year^-1. Water provision in both countries has traditionally relied on supply-side sources, and the potential for expansion is becoming dim, making efforts towards demand management approaches more feasible. Findings show that CBM （community based management） systems of water points offer an alternative in terms of ownership and self-reliance based on institutional arrangements at community level. However, the CBM system involves some forms of payment for water access, and affordability has become a main challenge, to the extent that some governments are considering the reintroduction of water subsidies for poor rural communities in the near future.