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In Turkey, an average of 450 sewer line tenders are made annually and the total line length of these works is approximately 11000000 m. It is very important for both the investor and the contractor to know the costs of the sewer networks with such a large business volume. In this study, models are developed for early estimation of sewage line costs by the regression analysis method. Data belonging to 182 sewer line projects were used in the development of the models. Data on pipe diameter, line length, excavation depth, manhole amount, excavation amount, filling amount, filling type, shoring type, excavation class and real cost parameters were determined through the projects. Correlations between the determined parameters were specified and the parameters suitable for regression analysis were selected. As a result; among the developed estimation models, the equation using all selected parameters with a correlation coefficient of R² = 0.911 gave the most successful result.

Introduction: The restoration of old fountains is essential to the cultural life of society since it preserves the architectural spirit of the past and conveys the historical heritage to the present day. Besides, fountains create a favorable atmosphere in summer, humidifying the air. In the course of the study, we developed an approach to the restoration of the engineering systems and the technology of operation of an old fountain in St. Petersburg. Methods: We performed a detailed survey of the cast-iron fountain body and the pits next to it to discover the catchment basin of the fountain and establish its dimensions, assess the operation of similar fountains, analyze historical documents (old photos), and design engineering systems. Results and discussion: As a result of the study, the dimensions of the fountain and the catchment basin as well as the diameters of the orifices were obtained. The trajectories of the water jets and the scheme of the fountain’s operation were determined. Besides, we performed a hydraulic analysis of the systems and selected the necessary equipment. In this paper, we also present the scheme of the fountain’s operation in the following modes: filling with water, normal operation, and shut-down for winter.

В статті розглядаються питання конструкції робочого органу кабелеукладача при прокладанні кабелю безтраншейним способом. Проведено аналіз по вдосконаленню робочого органу кабелеукладача та основні переваги безтраншейної прокладки кабелів. Безтраншейна укладка кабелю в ґрунт – це ефективна технологія, яка надає можливість не руйнувати верхній шар ґрунту під час проведення підземних робіт. Завдяки цьому зникає необхідність перекривати дороги, порушувати цілісність існуючих комунікацій, знищувати насадження. Безтраншейна технологія прокладання кабелю дозволяє не тільки зменшувати матеріальні витрати, але і скорочувати час виконання робіт. Тривалість укладки кабелю буде залежати від таких факторів, як перешкоди у вигляді доріг, автомагістралей, будівельних об’єктів. Завданням безтраншейної прокладки є: прокладка мереж водопостачання, каналізації, газопроводу; прокладка кабелів електропостачання, телефонних і оптоволоконних кабельних ліній зв'язку та сигналізації; заміна зношених комунікацій на нові; прокладка каналізації будь-якого виду. Також в статті висвітлено аналіз вдосконалення конструкції кабелеукладачів з активними землерийними робочими органами (ЗРО), принцип дії яких заснований на безтраншейному способі, які також мають обмежену швидкість робочого руху та відносну швидкість робочого органа, складність конструкції та низьку експлуатаційну надійність. Аналіз вітчизняних і закордонних конструкцій безтраншейних укладачів показав, що в практиці будівництва підземних комунікацій застосовують більше 60 моделей машин з різноманітними землерийними робочими органами за формою робочої поверхні, які по різному впливають на ґрунтове середовище. За даними попередніх досліджень найперспективнішими є безтраншейні причіпні кабелеукладачі з пасивним землерийними робочими органами. Однак, незважаючи на вказані переваги, безтраншейний спосіб будівництва ще не набув широкого розповсюдження. Це пояснюється тим, що традиційні робочі органи безтраншейних укладачів працюють за принципом розрізання і запресування ґрунту в стінки щілини, що нарізається.

The article deals with the essence and peculiarities of the industrial development of the construction and architecture of Kyiv in the second half of the 19th century.The research covered the industrial complex of Kyiv at that time, including the development of the industry, the construction of bridges, the creation of the railway industry and the first engineering systems: water supply, sewerage, electric transport (tram and funicular).Prerequisites for the development of construction and the emergence of the profession of civil engineer are considered.The data on the construction and subsequent history of the existence of the Mykolaiv-Kiev chain and Darnytsia railway bridges of Kyiv are given.The technological, construction and structural achievements in the construction of the first Kiev railway junction are described - the technology of arrangement of drilling piles for strengthening the foundations of buildings and structures of the engineer AE. sewage system.The drawings depicting the appearance, plans and schemes of buildings and structures, erected in the second half of the nineteenth century.The analysis of architectural forms and stylistic directions of buildings and structures, engineering achievements and town-planning decisions, introduction of new structures and building materials that left a significant mark and significantly influenced the development of construction of Ukraine., В статті розглянуто сутність та особливості індустріального розвитку будівництва та архітектури Києва у другій половині ХІХ ст.Дослідженням охоплений виробничий комплекс тогочасного Києва включаючи розвиток промисловості, зведення мостів, створення залізничного господарства та перших інженерних систем: водогону, каналізації, електричного транспорту (трамваю і фунікулеру).Розглянуто передумови розвитку будівництва і виникнення професії інженера-будівельника. Наведені дані про спорудження і подальшу історію існування Миколаївського ланцюгового і Дарницького залізничного мостів Києва.Описані інженерно-технологічні та будівельно-конструктивні досягнення при зведенні першого Київського залізничного вузла – технологію влаштування буронабивних паль для підсилення фундаментів будівель і споруд інженера А. Е. Страуса та особливості будівництва і експлуатації першої в Києві системи міського водогону та каналізації.Наведені рисунки із зображенням зовнішнього вигляду, планів і схем будівель і споруд, зведених у другій половині ХІХ ст. Представлено аналіз архітектурних форм і стилістичних напрямів будівель і споруд, інженерні досягнення та містобудівельні рішення, впровадження нових конструкцій та будівельних матеріалів, які залишили після себе значний слід і суттєво вплинули на розвиток будівництва України.

Introduction. The main task of treating sewage sludge is to obtain the final product, the properties of which would ensure the possibility of its utilization and minimize the damage to the environment. The sanitary and hygiene characteristics of the sediment are assessed by the presence of pathogenic microorganisms and helminths eggs. The degree of disinfection of the sediments is controlled according to SanPiN 2.1.7.573 - 96. The objective of the work. Determination of optimal doses of caustic lime for disinfection of microbial contamination of sewage sludge of household wastewater of sewerage cleaning facilities (SCF) and liquid manure of the swine complex. Material and methods. The object of the study were microbial communities of the sludge of the SCF household wastewater and liquid manure of the swine complex. Standard microbiological research methods were used in the work according to MU 2.1.5.800 - 99 and MR N FTs/4022. For representativeness, analyses were performed in triplicate. Results. Caustic lime was added in the amount of 1 to 10% of the volume (mass) of the sludge under study into the sludge of household wastewater (humidity of 97 - 98%). The contact time was 0.5 hours, 1 hour, 3 hours. At a concentration of caustic lime of 5 and 6%, the absence of microflora was noted after 1 hour, at a concentration of caustic lime 8 - 10% - after 0.5 hours. After 3 hours, for any amount of caustic lime (from 1 to 10%) in the native sludge of wastewater sewerage, all the microorganisms under study were not shown. Into the liquid manure (humidity less than 85%), caustic lime was added in the amount of 4 - 10% of the volume (mass) of the material being examined. The exposure was of 1 and 3 hours. The complete death of microbes at any exposure was observed at a concentration of caustic lime 9 and 10%. Conclusion. The investigations have shown the dynamics of death of microorganisms in studying the impact of caustic lime on both native and sterilized material to be the same. The total death of microorganisms during the treatment of sludge from household wastewater was observed at a concentration of caustic lime of 7 - 9%. The complete death of microbes in liquid manure (native and sterilized) at any exposure was observed at a concentration of caustic lime 9 and 10%.

Bekiroglu/0000-0002-9883-0250; Elmas, Gulnur Mertoglu/0000-0002-4481-3850 WOS:000478803800031 Toilet paper is widely used in residences. The low biodegradability of toilet paper's pulp fibers can cause residence sewer lines to clog, which may be due to some additives or the presence of nonwoven fiber products. In this study, the disintegration rate of toilet paper was compared against various physical factors of the toilet paper sheet. The samples were disintegrated in water at varying pH levels. In the manufacturing of toilet paper, there must be a balance between the desired softness and the necessary wet strength. Twelve commonly used brands of toilet paper were purchased locally. Physical factors of toilet paper samples such as degree of polymerization, thickness, grammage, and softness were determined. The samples were evaluated based on 9 variables using correlation and multivariate linear regression analyses. A strong positive relationship was found between the degree of disintegration of toilet tissue paper and its physical factors. These were the degree of polymerization, the grammage, thickness, and the softness. Additionally, the amount of polymers applied to toilet paper decreased the degree of softness and adversely affected the redispersion of fibers. Thus, this work supports the idea that toilet paper can contribute to clogging of residential sewerage lines.

Accidents on sewers accompanied by the destruction of building structures have been a most serious problem not only for the water industry but also for the entire city. In the world the damage from the deterioration of reinforced concrete sewer tunnels and in-line structures due to corrosion is estimated at billions of euros per year. A way out of the current situation with corrosion in sewers can be timely and prompt repair and rehabilitation using protective coatings applied by trenchless methods. One of the methods of sewer rehabilitation is lining the internal walls of the sewers with plate composite materials (blocks) or continuous protective coatings where polymer concrete can be used. Polymer concrete comprises a thermosetting organic binder (usually epoxy resin) and a large amount of dispersed filler (talc, aerosil, crushed quartz, basalt, granite chips, etc.). The special composition of filler materials and advanced production technologies ensures the high qualities of polymer concrete. An assessment of the technical and economic indicators of the reconstruction of existing sewers and canals using polymer concrete blocks is given. Through a realistic example it is shown that the most effective option of the reconstruction of a sewer canal while ensuring environmental safety is lining with polymer concrete blocks (segments).

The final publication is available at Springer via http://dx.doi.org/10.1007/s11269-015-1214-5 The demand for sanitation infrastructures is increasing due to a rise in the urban population. To meet the need for wastewater collection, the construction of sewer networks must comply with a series of technical parameters that indicate whether a solution is feasible or not. Considering that this construction implies a series of environmental impacts, this study coupled a structural analysis of one linear metre of sewer constructive solutions with their life cycle impacts. Different pipe materials (concrete, polyvinylchloride (PVC) and high-density polyethylene (HDPE)) were combined with different trench designs and their environmental performance was assessed using Life Cycle Assessment (LCA). These solutions complied with technical parameters consisting of traffic loads and pavement conditions, among others. Concrete pipes embedded in granular matter result in fewer environmental impacts, such as Global Warming Potential or Cumulative Energy Demand. Further, re-using the excavated soil results in up to 80 % of environmental savings with respect to extracting new materials. Concerning traffic loads and pavement conditions, failures in plastic pipes could be avoided if these are embedded in concrete. Moreover, the environmental impacts of this solution are similar to those resulting from the substitution of pipes that do not comply with the mechanical requirements of the construction site. Therefore, proper planning is needed to provide cities with sewers that are resilient to time and external loads and reduce the urban environmental impacts.

En este documento doy a conocer mi pasantia como opción de grado que realice en el CONSORCIO AGUAS DUITAMA 2019 según el contrato de obra N° 004 cuyo objeto es “CONSTRUCCIÓN Y OPTIMIZACIÓN DEL SISTEMA DE ALCANTARILLADO SANITARIO Y PLUVIAL DEL SECTOR QUEBRADA LA AROMA-GLORIETA LAS AMERICAS EN EL MUNICIPIO DE DUITAMA DEL DEPARTAMENTO DE BOYACÁ”, contratada por la empresa “PEDRAZA INGENIERIA SAS” siendo un apoyo técnico en la supervisión el proceso constructivo de 575 metros lineales de alcantarillado pluvial, 11 pozos de inspección y una cámara de inspección construidos en concreto reforzado de 4000 PSI , igualmente realizando otras actividades administrativas como manejo del presupuesto que me disponía el consorcio, reporte de pagos al personal de obra no calificado, maquinaria, combustibles y materiales de obra, garantizando que estas labores estén realizadas con la mejor calidad, honestidad y cumplimiento con las normas técnicas Colombianas establecidas. In this document I present my internship as a degree option that I carry out at the AGUAS DUITAMA 2019 CONSORTIUM according to work contract No. 004 whose object is "CONSTRUCTION AND OPTIMIZATION OF THE SANITARY AND RAINWATER SYSTEM OF THE QUEBRADA LA AROMA-GLORIETA LAS SECTOR AMERICAS IN THE DUITAMA MUNICIPALITY OF THE BOYACÁ DEPARTMENT ”, hired by the company“ PEDRAZA INGENIERIA SAS ”, providing technical support in the supervision of the construction process of 575 linear meters of storm sewerage, 11 inspection wells and an inspection camera built in 4000 PSI reinforced concrete, also carrying out other administrative activities such as managing the budget set forth by the consortium, reporting payments to unskilled construction personnel, machinery, fuel and construction materials, guaranteeing that these tasks are carried out with the best quality, honesty and compliance with the established Colombian technical standards. Pregrado

Данная работа посвящена разработке мероприятий по обеспечению инженерной подготовки территории населенного пункта. Задачи, которые решались в ходе работы: 1. Вертикальная планировка, обеспечивающая поверхностный сток талых и дождевых вод 2. Разработка закрытой системы дождевой канализации, способствующей удалению талых и дождевых вод за пределы населенного пункта 3. Разработка дренажной системы, предохраняющей территорию от возможного подтопления в результате высокого уровня грунтовых вод. 4. Обеспечение пожарной безопасности и пожаротушения территорий. Территория, подлежащая разработке мероприятий для благоустройства и инженерной подготовки, представляет собой проектируемы населенный пункт в Новгородской области. проект разработан с учетом технического задания на проектирование и всех требований действующих нормативных документов. Результатом работы является разработка мероприятий по вертикальной планировке территории, обеспечению стока талых и дождевых вод, защиты территории от подтоплений, обеспечение соответствия территории требованиям пожарной безопасности., This work is devoted to the development of measures to ensure the engineering preparation of the territory of a settlement. Tasks that were solved in the course of work: 1. Vertical layout, providing surface runoff of melt and rainwater 2. Development of a closed rainwater drainage system that contributes to the removal of melt and rainwater outside the village 3. Development of a drainage system that protects the territory from possible flooding as a result of a high level of groundwater. 4. Fire safety and fire fighting of territories. The territory subject to the development of measures for improvement and engineering training is a projected settlement in the Novgorod region. The project was developed taking into account the technical specifications for the design and all the requirements of current regulatory documents. The result of the work is the development of measures for the vertical layout of the territory, ensuring the flow of melt and rainwater, protecting the territory from flooding, ensuring compliance with the fire safety requirements.

In the conditions of laboratory model experiment on composting of sewage sludge the influence of active phosphate-mobilizing bacteria on the release of water-soluble forms of phosphorus was studied. The experimental scheme included known active phosphate-mobilizing bacteria isolated from various ecological niches. The following components were used for composting: sewage sludge (SS), winter wheat straw and a suspension of phosphate-mobilizing microorganisms isolated from SSs of municipal treatment plants. The largest increase in water-soluble forms of phosphorus at the final stage of composting due to the introduction of Microbacterium barkeri. The greatest growth of water-soluble forms of phosphorus at the final stage of composting is provided by the introduction of Microbacterium barkeri LP-1, which can be explained by the greater adaptation of this strain to the substrate used in the experiments.

Time-cost models have been developed in various contexts to assist in forecasting the duration of different types of projects. The present research explores the influence of the construction technology on the time-cost relationship. For that purpose, the data from 21 sewerage projects using trenchless technology and from 49 sewerage projects using the traditional open-cut method was analyzed. The 70 sewerage projects analyzed were completed in Chicago, U.S., between 1994 and 2002. The influence of the construction technology in the time-cost relationship was found to be statistically significant and time-relationships were determined for sewerage projects using trenchless technology and the traditional open-cut method. Furthermore, along with the Bromilow type models an alternative approach was tested using the time normalized by the project cost as dependent variable, allowing additional insight into the time performance of the open-cut and lining technology used (cured in place).

Purpose This paper aims to investigate the condition and select a repair procedure for a damaged sewer in Kharkiv, Ukraine. Design/methodology/approach Inspection shafts are critical objects in the sewerage networks and are exposed to the strong influence of destructive processes, which are mainly corrosion of concrete structures, penetration of surface water inside structures, static and dynamic loads generated by truck transport, deviations from the codes and errors in construction, poor quality of the shaft wall surface, aggressive biological environment and ground subsidence. Therefore, selecting the optimum repair technology is of current interest. Findings The problems of repair and refurbishment of inspection shafts in deep-level sewer tunnels were considered. The technical and technological solutions using profiled polyethylene, reinforced slag cast panels, ceramic bricks and protective coatings are given. The advantages and disadvantages of the proposed technologies and examples of their practical application are shown. Originality/value This study performs reconstruction and strengthening work for a damaged section of the inspection shaft without shutdown.

In the field of rehabilitation of separate sanitary sewer systems, a large number of technical, environmental, and economic aspects are often relevant in the decision-making process, which may be modelled as a multi-objective optimization problem. Examples are those related with the operation and assessment of networks, optimization of structural, hydraulic, sanitary, and environmental performance, rehabilitation programmes, and execution works. In particular, the cost of investment, operation and maintenance needed to reduce or eliminate Infiltration from the underground water table and Inflows of storm water surface runoff (I/I) using rehabilitation techniques or related methods can be significantly lower than the cost of transporting and treating these flows throughout the lifespan of the systems or period studied. This paper presents a comprehensive I/I cost-benefit approach for rehabilitation that explicitly considers all elements of the systems and shows how the approximation is incorporated as an objective function in a general evolutionary multi-objective optimization model. It takes into account network performance and wastewater treatment costs, average values of several input variables, and rates that can reflect the adoption of different predictable or limiting scenarios. The approach can be used as a practical and fast tool to support decision-making in sewer network rehabilitation in any phase of a project. The fundamental aspects, modelling, implementation details and preliminary results of a two-objective optimization rehabilitation model using a genetic algorithm, with a second objective function related to the structural condition of the network and the service failure risk, are presented. The basic approach is applied to three real world cases studies of sanitary sewerage systems in Coimbra and the results show the simplicity, suitability, effectiveness, and usefulness of the approximation implemented and of the objective function proposed.

The importance of water in life and health of population, especially in developing countries, justifies the comparative study of the performance of undertakings providing potable water and waste water collection. The main objective of this research is to investigate if the decentralization process has led to an improvement of the efficiency in the water industry. Using a stochastic frontier analysis, we show that technical efficiency of Venezuelan water companies remained around 84% and that decentralized companies were more efficient than the centralized ones. The main policy recommendation is that the process of decentralization in the water services should continue.

Healthcare facility discharges, by their nature, are often considered as non-domestic effluent, which can provide significant pollution comparatively to other domestic sources. In this context, a total of 12 monthly sampling campaigns were collected from a healthcare facility as well as the output of a sewerage system of Site Pilote de Bellecombe (SIPIBEL) observatory. This study focuses more specifically on 12 surfactants and biocides: four anionics, four cationic, two non-ionic, one zwitterionic, and one dispersive agent, among the most commonly used commercial surfactants. Particular attention was also provided to routine wastewater quality parameters. Both effluents were heavily contaminated by most anionic surfactants; they displayed median concentrations up to 1 to 2 mg/L for linear alkylbenzene sulfonates and between 10 and 100 μg/L for other sodium sulfate congeners (lauryl and laureth). Overall, for the majority of surfactants, the healthcare facility contribution to the total flux reaching the wastewater treatment plant ranges between 5 and 9%.

Aura, the ‘City of Colour’, is a 48,000 person masterplanned community on Queensland's Sunshine Coast. Aura commenced construction in 2015 and will be developed over the next 25 years. Aura sets a benchmark in Australia regarding large scale urban water sustainability through the application of techniques such as rainwater capture and reuse, construction and operational stormwater treatment, water conservation, advanced sewer system designs and potentially a major stormwater harvesting and indirect potable reuse scheme. This paper outlines the journey taken in seeing Aura advance from ‘concept’ to ‘reality’, describes data collection undertaken and modelling tools applied and outlines activities being implemented at Aura to protect sensitive downstream environments and simultaneously deliver water cycle and project sustainability benefits.

In the process of design and operation of sewerage system are used empirical formulas, which are in many cases, become obsolete and unusable when somebody can use nowadays modern technologies and materials. Therefore there is the possibility of using the mathematical models enormous importance for the enhanced environmental protection with the lowest operating and investment costs. In this modern method of analyzing of sewers has been designated as the first object, the object sedimentation tank. The purpose of the primary and secondary settling tank is to ensure the reduction of concentration the floating solids. For the solution of research work has been chosen, after consultations with representatives of the Western Slovakia Water Company as interesting object of sedimentation tank located on the waste water treatment plant Nitra - Dolné Krškany. Measurements on the object settlement tank situated at waste water treatment plant Nitra confirmed the expected speed parameters of the sewage in the tank. The velocity of wastewater is in the most cases very low, and even insignificant. However, finding that the sludge cloud has a non-standard form of a double wave gives the opportunity to optimize the operation of facilities sedimentation tank. The measured parameters are used as calibration parameters to input to the mathematical simulations, which are created by software ANSYS fluent.

This paper presents results of a household survey on the current sanitation and sewerage conditions in Metro Manila. The survey included a choice, measured in terms of the marginal willingness to pay (MWTP), between two alternative domestic wastewater treatment systems: 1) a sewerage system connecting individual households to a treatment plant through sewer lines; and 2) a combined drainage–sewerage system in which wastewater effluent flows with rainwater through flood canals and is intercepted for treatment only at a certain point in the waterway. With the second, the health improvement effect may be limited, but the cost can be significantly lower. The finding in favour of the combined drainage–sewerage system lends some support to this new approach in municipal wastewater treatment, which some other increasingly congested metropolises in Asian countries are likewise adopting, as an alternative to the more costly individual household sewer connections.

In relation to established plans of district heat supply facilities that make effective reuse of heat obtained from sewage, we developed GIS software to perform analyses of the spatial congruence between heat demand and the use of waste heat in heat supply operations. Based on an analysis using this GIS, we also explored plans for determining locations of heat-recovery facilities in Tokyo. Additionally, we assessed the suitability of heat-supply operations for individual geographical areas by evaluating their heat supply/demand relationships. In the areas with a large amount of usable heat, there are generally long sewerage lines and many possible heat recovery locations. We therefore chose indicators that represent the characteristics of the heat supply/demand relationship for each line. Taking into account the way sewerage line groups were formed, the representative indicators chosen were the values of the utilization factor and the amount of usable heat per heat pump when pumps were installed in three locations on a sewerage line. A large usable heat amount per pump is an advantage in establishing district heat supply operations. In that sense, the Shibaura treatment district is already highly suited to establishing heat supply operations.

The assessment of productivity change and its drivers across water companies and over time is a powerful tool for both regulators and companies when setting water tariffs. Water and sewerage companies (WaSCs) and water only companies (WoCs) provide different services. Hence, their productivity change cannot directly be evaluated jointly. In this paper and for the first time, we provide a pioneering approach to assess and compare the dynamics of productivity change of WaSCs and WoCs. To achieve this, both the traditional Malmquist productivity index and the metafrontier Malmquist productivity index and its components are computed to assess the productivity change for a sample of English and Welsh water companies over the period 2001-2014. The findings from both indices indicate that productivity for both WaSCs and WoCs did not improve during this period, mainly due to the negative shift in the production frontier which offset the positive effect of efficiency change. It is also reported that the performance of the WoCs over time was slightly better than that of the WaSCs. Finally, our study provides some insights into the relationship between productivity change and the regulatory cycle. This information is essential to improve the regulation of water and sewerage services, contributing to the long-term sustainability of the urban water cycle.

Flow characteristics are significant in the design of sewerage systems in that poor analysis of the flow design parameters may influence the capacity of a sewerage system, causing health and environmental problems. The aim of this study is to verify the design parameters in the peak flow factor equation in Malaysian Standard Code of Practice MS 1228:1991. Data collection was conducted in a residential area at Taman Lepar Hilir Saujana, Kuantan, Pahang. ISCO 2150 Area Velocity Flow Meter and ISCO 674 Rain Gauge were used in this study to collect flow rate and rainfall intensity data, respectively. The resultant analysis shows that the flow design parameters, per capita flow and design criterion, were unexpectedly 42·2 and 16% lower than the value of per capita flow and design criterion described in MS 1228:1991, respectively. This indicates that the separate sewer systems in Malaysia may be overdesigned if using the flow design parameters recommended in MS 1228:1991. Thus, a revision of the flow design parameters may be necessary, taking into account the rising cost of materials around the world.

Non-revenue Water (NRW) is an important component of commercial water system management. NRW is the result of pipelines leakage, improper, illegal service connections and theft water. NRW contributes system loss that is a buzzword. Actually, NRW is uncounted water that has been produced but it is confirmed to be “lost” before it consumes the customer. This matter agitates for all concern and specially it affects the whole economy. Dhaka Water Supply and Sewerage Authority (DWASA) is one of the main utilities in Dhaka City and it is the mostimportant sector of the Government of Bangladesh. The potable water distribution network has been installed at the whole area of the city and it covers periphery of the city and its extension is going from N. Gonj to Tongi as well as surrounding area of this city. Non-revenue water surveys were conducted on specific fields and areas that were selected randomly. It would be gradually becoming a serious issue affecting the interest of all concerned andwould be one of the major crises to be solved with techno-managerial concept.

The article presents modern methods of hydraulic design of an innovative small diameter gravity sewerage system. In this system, domestic wastewater is preliminary treated in septic tanks equipped with outlet filters, thus the effluent features are similar to those of clear water. Innovative non-return valves at the outlets eliminate introduction of air to the system and thus the flows can be treated as one-phase ones. Computer codes EPANET 2 and SWMM 5.0 were applied and compared. Two flow schemes typical for the sewerage system were implemented in EPANET 2, and the third - in a slightly modified SWMM 5.0. Simulation results were validated on empirical data obtained on a laboratory physical model, consisting of four tanks of minimum volumes 600 dm3 each, connecting PE pipelines of diameters 25 mm and 36 mm and relevant sanitary fittings. Water inflows, typical for domestic wastewater outflows from single homesteads, were provided by a pump. Water flows were measured using water meters with pulse outputs, and water levels in tanks by pressure transducers. Hydraulic characteristics of filters and non-return valves were provided. Simulation results showed good agreement with the empirical data. Ranges of values of design parameters, needed for successful application of both codes, were established and discussed.

Increasing demand for water and energy sources, accompanied by continued increases in the prices of these sources, has been observed worldwide. This has resulted in the need to seek alternative sources. In response to this statement, a cost-effective analysis has been carried out to enable the use of selected systems to reduce demands for potable water and natural gas used for heating in single-family homes. The study includes the Drain Water Heat Recovery System, Gray Water Harvesting System and Rainwater Harvesting System. The Life Cycle Cost methodology has been applied as a tool for the analysis. Depending on the number of users and rate of piped water consumption the determined Life Cycle Cost indicator ranged from €11519 to €19678. The study has shown that the highest life cycle cost are characteristic of the graywater recycling variant. In circumstances where water consumption in homes for purposes of showering and toilet flushing exceeded 300 L per day, the most cost-effective is the option that combines all systems analyzed. The most preferred, in the other cases was the use of Rainwater Harvesting System. The sensitivity analysis carried out has also shown that costs changes associated with building water supply and sewerage facilities has had the greatest impact on life cycle costs of each solution. The analysis have shown that the systems under consideration could serve as alternatives for traditional installations. Their use has resulted in reductions in the consumption of fossil fuels and natural water resources, thus contributing to environmental improvements.

PUB Singapore has been developing the membrane bioreactor (MBR) technology for water reclamation. The MBR technology has significant versatility and can be applied for production of industrial water or combined with reverse osmosis to produce NEWater. The MBR technology offers greater opportunity for process intensification and further enhancement to achieve water sustainability. Compared to conventional treatment, MBR is a 3-in-1 solution that combines bioreactor, secondary sedimentation tank and microfiltration/ultrafiltration in one single step. The advantages of MBR include process robustness, superior filtrate quality and compact footprint. Progressing from pilot studies and demonstration testing, the MBR technology is currently implemented at full-scale in Jurong and Changi Water Reclamation Plant. Moving forward, PUB continues to embark on R&D in developing innovative MBR systems for future application that includes the forthcoming Tuas Water Reclamation Plant as part of the Deep Tunnel Sewerage System Phase 2 project. This manuscript provides an overview of R&D initiatives for developing the MBR technology for water reclamation spanning more than a decade at PUB.

Good practice and standards set strict requirements for optimization and continuous improvement of physical asset management. The new international standard for asset management provides a framework for asset intensive industries to develop and implement sound asset management systems. Unlike the largest and most global industries, there are very few, if any, providers of services in the water sector that have developed and implemented a full set of best practices, in compliance with specifications created by the standard. Oslo Water and Sewerage Works (Oslo VAV) has worked systematically to evolve its asset management system by standardizing work processes and operating procedures in its Business Process Management System, implementing good practice in infrastructure asset management, and by improved management and control of the private contractor that operates the wastewater treatment plant's processes and activities. This paper provides insight into Oslo VAV's asset management system, assessment of current practice vs. best practice for complying with the standard and high priority areas for improvement.

Sanitation and hygiene technologies have existed in ancient Hellas since the Bronze Age (ca. 3200–1100 bc), when extensive sewerage and drainage and other elaborate sanitary structures were known in Minoan palaces and towns. Classical and Hellenistic periods should be considered as the most progressive eras in the design of sanitary engineering. At that time anatomically shaped toilet seats are found in several sites since many private houses and public buildings have them. As cities grew in size the pressure of larger populations resulted in the construction of communal toilets with seats that were more densely packed together. Drainage and sewerage systems and sanitary installations reflect high cultural and technological levels and they are associated with contemporary observations and ideas about hygiene and medicine. Before the Hellenic advances, medicine was entirely confined to religious beliefs and metaphysical rituals. In the early Roman period, the knowledge of the ancient world on hygienic matter was incorporated in legislative rules. Despite the weakening of this legislation through the ages, the sanitation practices kept being applied even via a technical tradition of the masons. Later various rulers of the Hellenic world (Europeans or Ottomans), introduced their practices (traditional/scientific) sanitation in the greater Helladic regions.

Significant characteristics of the Minoan civilization were: (a) their peaceful living with their environment and neighbors (although the Minoans dominated in the Mediterranean for almost two millennia, in none of the numerous wars and/or conflicts that occurred in the region were they directly or indirectly involved) and (b) technological developments that are unprecedented in world history, as shown by the numerous paradigms on water resources technologies used and water, wastewater, and stormwater management. These paradigms are relevant to water supply, fountains, cisterns used to store rainwater or spring water, aqueducts, dams, wells, water treatment systems, baths and toilets, sewerage and drainage systems, irrigation and drainage of agricultural land, and water use for recreation. Significant hydrologic and hydraulic achievements in Minoan Crete are considered and discussed.

In dense population cities, the effectiveness of the communal system in handling municipal domestic wastewater is important. This research aimed to evaluate the effectiveness of pipe dimensioning process and determine it as a wastewater collector to be served as a reactor through a tracer test. Thus, this work may give some inputs for a reliable design criteria for communal system in Indonesia. The reaserch area was at communal system on Tegal Kawung RT 05 RW 08. It served 37 household which was identified using built drawings and field checking. The number of communal septic tank user was 150 people who approximately use water of 134.33 L/person/day and more than 75% (107.46 L/persons/day )was discharged to the system. The tracer test was done between the control box with the distance of 27.94 m and diameter of 150 mm. Based on the mathematical model that was used, the diameter of the pipe should be 100 mm. The tracer test showed that the piping system is the Plug Flow Reactor but it is not yet effective, shown by the MDI value of 3.36.

Aguas de Manizales S.A. E.S.P. is a mixed-capital company, of a commercial nature, in accordance with the provisions of Law 142/94 and other applicable laws of the Republic of Colombia. According to Agreements 133 and 134 of September 1 st of 1995, issued by the Municipal Council of Manizales, the authorization for the establishment of companies that provide the public services in the form of joint-stock company was given. The institutionalization of the company in 1996, once the water distribution and drainage services were split from the other services offered by the former Public Service Porvider of Manizales ( Empresas Publicas de Manizales ), represented the beginning of an improvement period. This includes activities focused on conservation of water sources, refinement processes, extension of water networks, process standardization, setting up of laboratories, acquisition of new technology, as well as marketing of products and services easily accessible to the public through the water bill and with a high covering commercial network [1] .

One of the most influential ideals for constructing and managing cities and infrastructures worldwide is that of the ‘networked city'. This ideal refers to the technological design and morphology of cities integrated and ordered by infrastructure networks and to a specific model in the operation, use and planning of infrastructures. Engineers, planners and public health officials have aspired to align with this circulating ideal of urban modernity, hygiene and rationalization of nature in (re)producing cities worldwide. Like many cities in the global South, Dar es Salaam cannot be characterized by universal access to centralized water and sewerage networks. While formal institutions, planning documents and strategies reflect significations, as well as organizational and planning models of a networked city, its urban environments are shaped by hybrid arrangements manifesting unequal access to water and sanitation services. We build on postcolonial critique in urban studies and science and technology studies to inquire into this contradiction by addressing the translation of the ideal of the networked city in Dar es Salaam. Our objective is to uncover the negotiations over the translation of this hegemonic model, and to delineate the scope of creativity in reinventing alternative urban modernities that defy simplistic notions of technology transfer.

In this paper, road pavement collapses resulting from sewer leakage are divided into six categories: negligible, marginal, considerable, serious, very serious and catastrophic, with the categorization being based on two criteria, both related to traffic safety, i.e., the number of fatalities caused by sinkholes, and the extent of the road pavement damage. The causes of road pavement collapses are also discussed. The study involved analyzing the deterioration of sewer pipes with long service lives, focusing on the most common materials, i.e., concrete and vitrified clay. The results of the sewer inspections performed by the Kielce University of Technology suggest that the spot and linear defects detected in sewers of this type can be divided into three groups. The findings were used to formulate some recommendations on how to improve road traffic safety by preventing road pavement collapses.

This study is concerned with the feasibility of power generation using a pico-hydraulic turbine from sewage flowing in pipes. First, the sewage flow rate at two connection points to the Toyogawa River-Basin Sewerage, Japan, was explored for over a year to elucidate the hydraulic energy potential of the sewage. Second, the performance of the pico-hydraulic turbine was investigated via laboratory experiments that supposed the turbine to be installed in the sewage pipe at the connection points. This study indicates that the connection points have hydraulic potential that can be used for power generation throughout the year. It also demonstrates that the pico-hydraulic turbine can be usefully employed for power generation from sewage flowing in the pipe at the connection points.