Recent Developments in Oxygenation of the Tidal Thames

Increased polluting loads are discharged to the tidal Thames at times of heavy rainfall. This can lead to a rapid decline in dissolved-oxygen (DO) concentrations, which, on occasions, has resulted in fish mortality. The problem is caused by the cumulative effect of surface runoff, increased flows from sewage-treatment works, and storm-sewage discharges from the combined drainage of Inner London.
An experimental system of in-river oxygenation has been operated by Thames Water in order to alleviate the problem. This scheme demonstrated that the river oxygenation concept is viable. There was, however, a need to increase the operating reliability of the plant and to provide extra oxygenation capacity. Thames Water carried out a detailed investigation into the various options prior to the acquisition of a new, purpose-built, self-propelled, oxygenation vessel, which was delivered to the River Thames in October 1988.     

NEO河畔公寓

在这个严谨而杰出作品中,细部和建造技术格外受关注。建筑中每样东西都是美的创造。It＇s a tour de force of rigour,exceptional attention to detail,and engineering,Everything is beautifully made.这个住宅项目位于伦敦河畔地区的核心地带,它靠近泰晤士河,并与泰特现代艺术馆扩建部分的西门直接相对,NEO河畔公寓包括217个居住单元,分布于四栋建筑的12层至24层间。这四个六边形的大楼给居住者提供了舒适的居住条件、良好的景观视野和充足的阳光。这些钢和玻璃建造的塔楼,与周边环境形成了呼应。     

东伦敦城市更新背景下的伦敦2012奥林匹克公园

以东伦敦长达50年的城市更新规划为研究背景,针对伦敦2012年奥林匹克公园设计．从绿色基础设施的角度加以探讨并分析其对于整个城市发展的巨大作用。从时间维度上看,伦敦市政府强调了奥运会后遗产规划,将奥运场地远期发展纳入了始于1980年代的泰晤士河口城市更新计划中。从空间维度上看,奥林匹克公园作为重要的城市绿地,将成为东伦敦绿网、利亚区域公园、以及泰晤士河口绿地系统的重要节点,提升整个绿色基础设施的功能,从而实现可持续发展。     

Modelling algal behaviour in the river thames

Forecasting the movement and growth of algae in river systems as particularly important for operational managers responsible for the distribution and supply of potable water. Algae affect the taste and smell of water and pose considerable filtration problems at water treatment plants. In a collaborative study with the Thames Water Authority, algal models have been developed for the River Thames. The non-linear processes controlling algal growth are examined using a generalized sensitivity analysis technique and the dominant parameters controlling system behaviour are identified. The extended Kalman filter (EKF) is then used to estimate these important parameters. The technique of using generalized sensitivity analysis prior to EKF estimation is suggested as a pragmatic approach to the problem of identifying the subset of physically, chemically or biologically meaningful parameters controlling system behaviour in mechanistic models.     

Orthophosphate Concentrations in the River Thames

Observed concentrations of orthophosphate in the River Thames, from its source to its tidal limit, exceed 0.1 mg P/1 for most of its length; reasons for annual and seasonal variations are explained. By using data routinely collected by the Environment Agency throughout the Thames catchment, the orthophosphate load in the river, derived from agricultural sources and sewage-treatment works, is estimated.
A water quality model, TOMCAT, has been adapted to simulate observed data and used to estimate river concentrations if orthophosphate loads from sewage-treatment works are reduced.     

The London Water Ring Main: An Optimal Water Supply System

F aced with a continuing growth in demand and the need to replace a large part of London's ageing water supply system, Thames Water have devised an integrated strategy for future water supply to the capital. At the core of this strategy is the construction of over 60 km of deep tunnel (the London Water Ring Main) to convey water to the capital's major demand centres. The ring main will radically alter the way in which water is supplied to London, and a considerable amount of analytical work has been necessary to develop proposals and an operating system.     

Role of disinfection in suppressing the spread of pathogens with drinking water: possibilities and limitations

Transmission of pathogens with drinking water is a widespread problem, which affects not only the countries with low hygienic standards but the industrialized countries as well. The pathogens are excreted by man or animals and are picked up orally. Chlorination of drinking water has been introduced to the water supply in the beginning of the 19th century in order to stop the spreading of pathogens especially typhoid fever by drinking water. Despite the worldwide use of chlorine for disinfection of drinking water, water-mediated disease outbreaks occur again and again. Disinfection of drinking water with chlorine has undoubtedly contributed to the reduction of typhoid fever mortality. However, it must be clear that other factors play an important role in the mortality drop. Filtration of water is a long-known and very effective process for eliminating pathogens from the drinking water. Pathogens in particles cannot be killed sufficiently by a chemical disinfectant. Even small fecal particles have to be eliminated reliably from the water by filtration. Disinfection of drinking water cannot replace filtration. The disinfection should be used to minimize the residual risk due to the presence of pathogens in the water but cannot be used for bringing fecally contaminated water into a hygienically sound condition.     

Pharmaceuticals and personal care products (PPCPs) in surface and treated waters of Louisiana,USA and Ontario,Canada

A newly developed analytical method was used to measure concentrations of nine pharmaceuticals and personal care products (PPCPs) in samples from two surface water bodies, a sewage treatment plant effluent and various stages of a drinking water treatment plant in Louisiana, USA, and from one surface water body, a drinking water treatment plant and a pilot plant in Ontario, Canada. The analytical method provides for simultaneous extraction and quantification of the following broad range of PPCPs and endocrine-disrupting chemicals: naproxen; ibuprofen; estrone; 17beta-estradiol; bisphenol A; clorophene; triclosan; fluoxetine; and clofibric acid. Naproxen was detected in Louisiana sewage treatment plant effluent at 81-106 ng/l and Louisiana and Ontario surface waters at 22-107 ng/l. Triclosan was detected in Louisiana sewage treatment plant effluent at 10-21 ng/l. Of the three surface waters sampled, clofibric acid was detected in Detroit River water at 103 ng/l, but not in Mississippi River or Lake Pontchartrain waters. None of the other target analytes were detected above their method detection limits. Based on results at various stages of treatment, conventional drinking-water treatment processes (coagulation, flocculation and sedimentation) plus continuous addition of powdered activated carbon at a dosage of 2 mg/l did not remove naproxen from Mississippi River waters. However, chlorination, ozonation and dual media filtration processes reduced the concentration of naproxen below detection in Mississippi River and Detroit River waters and reduced clofibric acid in Detroit River waters. Results of this study demonstrate that existing water treatment technologies can effectively remove certain PPCPs. In addition, our study demonstrates the importance of obtaining data on removal mechanisms and byproducts associated with PPCPs and other endocrine-disrupting chemicals in drinking water and sewage treatment processes.     

实行全流域管理保护好黄浦江上游水源

通过对黄浦江上游水源污染的现状分析,提出了借鉴英国泰晤士河治理经验,理顺现有对黄浦江的管理体制,实行全流域管理的新思路。     

The water quality of the River Thame in the Thames Basin of south/south-eastern England

The water quality of the River Thame, a tributary of the River Thames in the Thames basin, is described in relation to point and diffuse contaminant inputs and runoff from permeable and impermeable bedrock geology with their own characteristic water quality. The data is examined to see if the market town of Aylesbury in the upper part of the catchment influences water quality. Previous studies highlighted the influence of Aylesbury sewage treatment works (STW) on soluble reactive phosphorus (SRP) concentrations in the river before and after phosphorus (P) stripping at the STW. Variations in water quality along the river are described and the study indicates that, apart from SRP, water quality determinants seem to be relatively unaffected by Aylesbury. The Thame water quality is compared with other catchment typologies and it is very similar to that of the main stem of the Thames even though the Thames is mainly Chalk groundwater fed. Differences in water quality largely link to the amount of STW effluent within the rivers and to the endmember compositions of the groundwater and near surface water sources.     

Escherichia coli contamination of the river Thames in different seasons and weather conditions

Contamination of public water ways with sewage represents a serious environmental and health risk. We monitored pollution of the river Thames by enumerating the indicator organism Escherichia coli. Samples were taken from a site in central London near Waterloo Bridge in different seasons. E. coli were quantified using a membrane filtration method, and correlated with the tidal variations of the river and meteorological data on rainfall and temperature. More frequent and severe incidents of pollution occurred in the autumn. Heavy rainfall resulted in sharp peaks of E. coli contamination that implies a potential increase of numbers of pathogenic micro‐organisms. Sixty percent of all samples were found to be in excess of the accepted upper limit of pollution set by European Union (EU) legislation for bathing water. This study demonstrated that frequent sewage pollution of the Thames results in high numbers of E. coli and incidents of detectable levels of pathogenic bacteria demonstrating the need for regular monitoring of bacterial pollution.     

Detection of enteroviruses in untreated and treated drinking water supplies in South Africa

Enteric viruses have been detected in many drinking water supplies all over the world. A meaningful number of these supplies were treated and disinfected according to internationally acceptable methods. In addition, counts of bacterial indicators (coliform bacteria and heterotrophic plate count organisms) in these water supplies were within limits generally recommended for treated drinking water and these findings have been supported by epidemiological data on infections associated with drinking water. The shortcomings of conventional treatment methods and indicator organisms to confirm the absence of enteric viruses from drinking water, was generally ascribed to the exceptional resistance of these viruses. In this study, the prevalence of enteroviruses detected from July 2000 to June 2002 in sewage, river-, borehole-, spring- and dam water as well as drinking water supplies treated and disinfected according to international specifications for the production of safe drinking water was analysed. A glass wool adsorption-elution technique was used to recover viruses from 10--20 l of sewage as well as environmental water samples, in the case of drinking water from more than 100 l. Recovered enteroviruses were inoculated onto two cell culture types (BGM and PLC/PRF/5 cells) for amplification of viral RNA with nested-PCR being used to detect the amplified viral RNA. Results from the study demonstrated the presence of enteroviruses in 42.5% of sewage and in 18.7% of treated drinking water samples. Furthermore, enteroviruses were detected in 28.5% of river water, in 26.7% of dam/spring water and in 25.3% of borehole water samples. The high prevalence of coxsackie B viruses found in this study suggested, that a potential health risk and a burden of disease constituted by these viruses might be meaningful. These findings indicated that strategies, other than end-point analysis of treated and disinfected drinking water supplies, may be required to ensure the production of drinking water that does not exceed acceptable health risks. More reliable approaches to ensure acceptable safety of drinking water supplies may be based on control by multiple-barrier principles from catchment to tap using hazard assessment and critical control point (HACCP) principles.     

Design and Construction of the Isle of Dogs Pumping Station

T he pumping station employs submersible pumps to drain surface water from the newly developed Enterprise Zone of the Isle of Dogs, London, and discharges storm overflows from an existing combined sewer system. At full development the nominal capacity of the pumps will be 12 m³/s.
After screening the flow passes to the pump chamber, where 12 main and two sump pumps are located. The main pumps deliver through individual syphon discharge pipes to a high level surge tank, which drains by gravity through a short outfall to the river Thames.
Diaphragm walling was used in the construction of the foundations and underground work. Attractive brick buildings form the pump hall and building housing the high voltage electrical equipment and the transformers. Steel sheet piles protect the river frontage.
The station will operate unattended, and will be controlled automatically by water level sensors. Supervision will be by telemetry links to the Thames Water Authority's (TWA) area control centre at Abbey Mills.     

Occurrence of perchlorate in drinking water sources of metropolitan area in Japan

The occurrence of perchlorate in the Tone River Basin was investigated using an ion chromatograph (IC) coupled with a tandem mass spectrometer (MS/MS). Perchlorate was found at high concentrations in the upper Tone River and its tributary, Usui River, and the maximum concentrations were 340 and 2300 microg/L, respectively. The possible sources of perchlorate in two areas were attributable to industrial effluents. In case of the upper Tone River, perchlorate concentration in an effluent was 1100 microg/L and its concentrations in a tributary (or waterway) directly downstream of the outlet of the effluent ranged from 44 to 1500 microg/L. In case of the Usui River, perchlorate concentration in another effluent was 15,000 microg/L and its concentrations downstream of the outlet of the effluent were 1100-3900 microg/L. Due to the discharge of perchlorate in the upper Tone River Basin, perchlorate concentrations in the river waters of the middle and lower Tone River Basin were generally 10-20 microg/L. Perchlorate concentrations in 30 tap water samples were investigated. Water sources of three tap water samples were other than the Tone River Basin and their perchlorate concentrations were 0.16-0.87 microg/L. On the other hand, water sources of the remaining 27 samples were the upper, middle and lower Tone River Basin and their perchlorate concentrations were 0.06-37 microg/L. Perchlorate concentrations were more than 1 microg/L in 19 tap water samples and more than 10 microg/L in 13 samples. It was shown that tap waters in the Tone River Basin were widely contaminated with perchlorate. To our knowledge, this study was the first to report on perchlorate contamination of environmental and drinking waters in Japan.     

Simultaneous removal of Cu, Mn and Zn from drinking water with the use of clinoptilolite and its Fe-modified form

Zeolites have been widely used in water treatment and especially clinoptilolite, due to its low cost and high abundance. It has large cation-exchange capacity and is capable of removing large quantities of heavy metals from contaminated water samples. By loading the surface of clinoptilolite with amorphous Fe-oxide species, a total improvement in adsorption capacity could be achieved. Thus, the Clin–Fe oxide system is capable of adsorbing significantly higher heavy metal concentrations than untreated clinoptilolite with simultaneous noticeable decrease in water hardness. Batch adsorption experiments have shown that Clin–Fe system has very large Cu, Zn and Mn adsorption capacity and for most of the cases the treated water samples were suitable for human consumption or agricultural use. New experiments were conducted to study the effectiveness of clinoptilolite and of the Clin–Fe system in removal of Cu, Mn, Zn, present simultaneously in water samples, so that the study of metal–sorbent chemical behavior and of the adsorption selectivity would be feasible. Desorption of metals was also examined and an integrated approach of the effectiveness of such materials in drinking water treatment is presented.     

Organochlorine Contamination in Sediments of the Inner Thames Estuary

The saltmarsh at Two Tree Island, situated in the Thames estuary, has previously been identified as exhibiting a relatively enhanced degree of contamination with respect to organochlorine insecticides and polychlorinated biphenyls. This survey of sediment samples from mud flats on the north bank of the River Thames, creeks surrounding Canvey Island and from Two Tree Island, indicated that contamination with organochlorine and polychlorinated biphenyls was ubiquitous throughout the inner Thames estuary. Values observed were in agreement with those in other European estuaries, and the degree of contamination at Two Tree Island was considered to reflect the local background. The outfall from Benfleet sewage-treatment works was identified as a possible source of contaminants: however, no other point sources were located. Samples of annelids taken from mud flats by Two Tree Island had accumulated penta- and hexa-chlorinated biphenyls to a greater degree than lower chlorinated cogeners, and demonstrated signs of an ability to metabolize DDT.     

Implementing a Sustainable Flood-Defence Strategy for London's Tidal Thames

The tidal flood defences in London protect the city and its citizens from potentially catastrophic flooding. In recent years there has been increased recognition of the environmental value of the tidal Thames; however, this environmental renaissance has been matched by increased river-side development, creating intense pressures upon the tidal Thames environment.
Building on the application of environmental assessment at the project level, the Environment Agency is developing new tools to evaluate the cumulative environmental impact of-works to individual frontages. Using current case studies, this paper describes practical examples of these approaches which aim to provide sustainable and economically justifiable flood defences and contribute to the enhancement of the tidal Thames.     

Determination of phenolic endocrine disrupting chemicals and acidic pharmaceuticals in surface water of the Pearl Rivers in South China by gas chromatography-negative chemical ionization-mass spectrometry

An analytical method for phenolic endocrine disrupting chemicals and acidic pharmaceuticals in river water was developed using gas chromatography mass spectrometry (GC-MS) coupled with negative chemical ionization (NCI) technique, and used for the determination of these compounds in the Pearl Rivers (Liuxi, Zhujiang and Shijing Rivers). Derivatization using pentafluorobenzoyl chloride (PFBOCl) and pentafluorobenzyl bromide (PFBBr) before GC-MS analysis were applied and optimized for phenolic compounds and acidic compounds, respectively. The target compounds were analyzed for river waters from the upstream to downstream of the Pearl Rivers. Phenolic compounds 4-tert-octylphenol (4-t-OP), 4-nonylphenol (4-NP), bisphenol-A (BPA), estrone (E1), estradiol (E2) and triclosan (TCS) were detected at trace or low levels in the water samples from Liuxi River and Zhujiang River. Diethylstilbestrol (DES) was not detected in the Pearl Rivers. The highest concentrations of the phenolic compounds were found in Shijing River, and they were 3150 ng/L for 4-t-OP, 11,300 ng/L for 4-NP, 1040 ng/L for BPA, 79 ng/L for E1, 7.7 ng/L for E2 and 355 ng/L for TCS, respectively. Only a few acidic pharmaceuticals were detected at low concentrations in water from Liuxi River and Zhujiang River, but the highest concentrations for the acidic pharmaceuticals were also found in Shijing River. The highest concentrations detected for clofibric acid, ibuprofen, gemfibrozil, naproxen, mefenamic acid and diclofenac were 17 ng/L, 685 ng/L, 19.8 ng/L, 125 ng/L, 24.6 ng/l and 150 ng/L, respectively. The results suggest Liuxi and Zhujiang Rivers are only slightly contaminated and can be used as drinking water sources, but Shijing River is heavily polluted by the wastewater from nearby towns.     

Application of ozone, UV and ozone/UV processes to reduce diethyl phthalate and its estrogenic activity

A research study to monitor the micropollutant levels present in the Han River, a major drinking water source for the Seoul Metropolitan district in Korea, was performed over a five-year period from 2000 to 2004, inclusive. Of the detected micropollutants, phthalates were found to be the major contaminants. In this study, the estrogenic activities of the detected phthalates and raw water samples contaminated with the pollutants were assessed by the E-screen assay using the MCF-7 breast cancer cell line. Of the phthalates, diethyl phthalate (DEP) and di(2-ethylhexyl) phthalate (DEHP) showed relatively high cell proliferation. Using DEP as a phthalate probe, three candidate processes, ozone alone, UV alone, and the ozone/UV combined, were evaluated for their efficiency in removing DEP and reducing its estrogenic activity. The ozone/UV process was shown to have the highest efficiency for the elimination of DEP and its by-products, leading to the complete mineralization of DEP. This study also found that the ozone/UV process is the best candidate to reduce the estrogenicity induced by DEP and its by-products.     

Effects of time and point-of-use devices on arsenic levels in Southeastern Michigan drinking water, USA

Health effects associated with chronic, low-level exposures to arsenic in drinking water (<100 microg/L) remain unclear, in part due to uncertainties in assessing exposure. Drinking water concentrations have been used to assess past exposure to arsenic in epidemiological studies, under the assumption that a single measurement can be used to estimate historical exposure. This study aims to better understand (1) temporal variability in arsenic concentrations in drinking water and (2) the impact of point-of-use (POU) treatment devices on arsenic exposure measurements, and on reliability of the exposure measurement for population-level studies. Multiple drinking water samples were collected at two points in time (an average of fourteen months apart) for 261 individuals enrolled in a case-control study of arsenic exposure and bladder cancer in Michigan. Sources of drinking water included private wells (n = 221), public water supplies (n = 33), and bottled water (n = 7); mean arsenic concentration was highest in private wells (7.28 microg/L) and lowest in bottled water samples (0.28 microg/L). Arsenic concentrations in primary drinking water samples were highly correlated (r = 0.88, p < 0.0001, n = 196), with 3% of the water sources exceeding the United States Environmental Protection Agency's Maximum Contaminant Level (MCL) in one sample but not in the other sample. Measurement reproducibility did not vary by type of POU device (e.g., softener, filter, reverse osmosis system). Arsenic concentrations did differ, however, between samples treated with POU devices and untreated samples taken on the same day. Substantial differences in arsenic concentrations were consistently observed for reverse osmosis systems; other POU devices had variable effects on arsenic concentrations. These results indicate that while a single residential arsenic measurement may be used to represent exposure in this region, researchers must obtain information on changes in water source and POU treatment devices to better characterize population exposures over time.