Outlet Points Research Articles

Contaminant Flushing in Water Distribution Networks Incorporating Customer Faucet Control

Contamination events in water distribution networks (WDNs) begin with contaminant inception in the network. WDNs respond to events according to the detection, stopping service, and recovery phases. The recovery phase aims to remove hazardous substances by flushing them out so that the network can return to normal conditions. Flushing must be conducted efficiently and safely. The contaminated water is removed by allowing it to flow from outlet points in the network, which is enabled by displacing it with clean water from the source. Conventionally, a hydrant was used as the outlet point. Recent advancements in information and communication technology allow the use of electronic media to broadcast warnings and guidance rapidly. Water utilities can convey information to customers as part of the flushing scheme by notifying them to open and close their faucets at designated times. In this study, the viability of customer involvement in decontamination was examined. The proposed method was tested by evaluating its effectiveness in terms of the time and volume of water needed for decontamination, and the change in hydraulics to drain a fully contaminated district metered area (DMA). A comparable performance to hydrant flushing was found after testing in two actual DMA-sized WDNs.

Experimental Study on Manned/Unmanned Thermal Environment in Radar Electronic Shelter Based on Different Air Supply Conditions

Studies on the thermal environment of the electronic radar shelter have been mainly focused on the simulation of the unmanned thermal environment, and there have been few studies on experiments in the thermal environment. Additionally, a comparative study of the experimental results from manned and unmanned shelters has been missing. In this paper, we experimented in thermal environments of manned/unmanned shelter under different air supply conditions. The experiment was divided into cooled, ventilated, and heated trials analyzing three aspects: (1) The average temperature distributions of walls, air inlet points, air outlet points, and surfaces were measured over time under different conditions in an unmanned shelter. The temperature distribution curve was fitted into the function. (2) Based on different working conditions, the temperature distribution experiments were carried out in three different areas for subjects wearing short or long clothing respectively. (3) The wind speed was measured at each measuring point in the air supply pipeline under different working conditions. The wind speed distribution was detected on the setting surfaces. The experimental results show that: (1) The air does not gradually tend to steady state with the time, and under different conditions, the air temperature obviously differs. (2) The clothing selection, air supply conditions, and locations of measuring points have significant influences on human body temperature distribution and left–right difference. (3) The mixing of the thermal plume caused by the vertical temperature difference of the human body and the jet generated by the mechanical air supply will reduce the wind speed of the airflow in the cabin, the adsorption of the jet to the bulkhead, and the stability of the airflow. The experimental data can provide the initial and boundary conditions for the simulation of the shelter. The results can provide a reference for the study of fluid control methods, the setting of thermal boundary conditions, and the simulation of the influence of thermal plumes on the airflow distribution. The experimental study in this paper has filled in the blanks regarding experimental study in electronic radar shelters. It has important research value and practical significance.

Improvement of Deep Learning Models for River Water Level Prediction Using Complex Network Method

Accurate water level prediction is one of the important challenges in various fields such as hydrology, natural disasters, and water resources management studies. In this study, a deep neural network and a long short-term memory model were applied for water level predictions between 2000 and 2020 in the Phan Rang River Basin of Nihn Thuan located in Vietnam. In addition, a complex network model was utilized to improve the predictive ability of both models for water level prediction at the outlet point of the basin. The water level prediction by each model was compared with the observed water level data, and the predictive power for each model was evaluated using three statistical metrics: the correlation coefficient (CC), the Nash–Sutcliffe efficiency coefficient (NSE), and the normalized root-mean-squared error (NRMSE). Using all data from nearby stations, there may be distortions in the prediction due to unnecessary data for model learning. Therefore, the complex network method was applied to find best data sources providing factors contributing to water level behaviors. The results of this study showed that a combination of the long short-term memory model and the complex network provided the best predictive performance (CC: 0.99; NSE: 0.99; and NRMSE: 0.17) and was selected as the optimal model for water level prediction in this study. As the need for disaster management is gradually increasing, it is expected that the deep learning model with the complex network method have sufficient potential to reduce the damage from natural disasters and improve disaster response systems, such as in the outskirts of Vietnam.

Assessment of Water Quality Status of Cengklik Reservoir due to Eutrophication

Cengklik Reservoir is one of the water sources that has the main function for irrigation and aquaculture. Based on satellite imagery of the Cengklik Reservoir 2000-2020, about 30% of the waters of the Cengklik Reservoir have been covered by water hyacinth. The use of chemical fertilizers, pesticides and fish farming activities using floating net cages are the main factors causing eutrophication. Therefore, the purpose of this study was to analyze the water quality of the Cengklik Reservoir at the inlet and outlet points of the Cengklik Reservoir and then determine the level of pollution using the Pollution Index (PI) method. The water quality parameters tested were temperature, pH, TSS, DO, BOD, COD, TSS, Total-P, and Total N. Based on the results of the PI analysis, the water quality of Cengklik Reservoir was categorized as lightly polluted and does not exceed the quality standard value of Government Regulation No. 22 years 2021 other than phosphate. Phosphate parameter values at inflow 1, inflow 2, inflow 3 and outflow locations are 0.166 mg/L; 0.166 mg/L; 0.723 mg/L and 0.166 mg/L which are estimates of the cause of eutrophication in the Cengklik Reservoir.

Activity of Ozonated Water in Sterilising and Disinfecting Dental Unit Water Pipelines System: A Comparative Study.

A number of disinfectants and sanitisers are used in dentistry, and there are numerous commercial solutions available. Nonetheless, because each cleaning solution has its own set of indications and limits, there is no one-size-fits-all approach for processing all types of dental equipment. Functional water, such as electrolysed hypochlorite microbubbled water, efficiently eliminates and sterilises biofilms. The objective of the study was to evaluate whether ozonated water could be used to sterilise and disinfect dental-unit water pipelines (DUWP) that had been contaminated with micro-organisms, including Gram-positive and Gram-negative bacilli and cocci. Three different groups were formed: group A - ozonated water (Cantoosh); group B - 1% povidine iodine; and group C: conventional distilled water. Group A was the test group, group B the control group, and group C was the positive control group. The water sterilising system was replaced with the appropriate sterilising agent as per the allocated group classification, with 2 min of purging, so that the complete DUWP was filled with the water sterilising system. Samples were collected and analysed, along with a 2-min purge after 24 h, 7 days and 21 days, at the 3 outlet (OL) points: the 3-way syringe at the dental tray(OL1), the cup filler (OL2), and the 3-way syringe of the assistant zone (OL3). Repeated measures ANOVA was used to test for statistical significance between colony-forming units of control and experimental groups (p < 0.05). The cup filler yielded higher counts than did the 3-way syringe at the dental tray (OL1) (6.40 and 8.05 on the log scale, respectively). A statistically significant difference in the CFUs was also observed between samples taken after 24 h vs 21 days between groups A, B and C. The findings showed that exposing DUWP tube systems to ozonated water for an extended length of time drastically lowered the number of microorganisms adhering to their surfaces.

Legionella Bacteria Activity investigation in Domestic Water Heating Systems: Tripoli-Libya as a case study

Legionella is a kind of bacteria that has been detected by many researchers in diffrent Water Heating Electrical (EWH) or solar (SWH) systems installed at various places. In the capital city Tripoli - Libya, most of water heater systems used are of electric type. Simultaneously, over 100 solar water heating (SWH) systems provided with electric heaters were installed under the supervision of the Centre for Solar Energy Research and Studies (CSERS) in the residential buildings in Tripoli in the period between (2000 and (2020). Ten hot water samples were collected from the outlet points in SWH systems and 43 water samples from diffrent water draining points at Corinthia hotel and Palm City Residences water systems, for the purpose of legionella detection and enumeration in the systems. A questionnaire was designed and distributed to be filed by the 10 SWH system users whom the ten water samples were taken from. Th purpose was to collect information about the building, the hot water system, and the user’s satisfaction. As the water source is untreated ground water from private wells, analysis of Escherichia coli (E.coli), total Coliform bacteria and total bacterial count were conducted to see whether any other probable bacteria kind is available. According to the results obtained, both 43 samples and 10 SWH samples investigated are free of legionella bacteria, while the total bacteria count for 4 out of 10 SWH systems was less than 60 CFU/g. Ths was due to water temperature not lowered to the bacteria colonisation temperature, and the daily water temperature gained from solar energy was high enough to be more than 55°C for at least an hour daily and maximum daily temperature exceeds 60°C for 80 days in addition to summer time, which is high enough to destroy legionella bacteria

Assessing the Benefits of Nature-Based Solutions in a Storm Drainage System – a Case Study

&amp;lt;p&amp;gt;In most developing countries, stormwater drainage practice consists of a conventional storm drainage system designed to collect and convey excess runoff to the recipient as soon as possible, without any attenuation or peak flow decreasing effects. This paper aims to show the overall need for change in the urban drainage paradigm by showing the effects of reconstruction of the existing conventional stormwater drainage system into a new one by including green elements. Part of the existing system is replaced with vegetated swales, and two detention ponds are added in the common green areas (parks). Effects are analysed through a comparison of results from a mathematical rainfall-runoff model for the existing and reconstructed stormwater drainage system for both water quality and quantity at the sub-basin outlet point. The cost-effectiveness of the applied measures is quantified by comparing construction prices for the existing and the reconstructed system. The obtained results clearly show an urgent need for stormwater drainage practice improvement in countries where the conventional approach is still in use.&amp;lt;/p&amp;gt;

ПРИМЕНЕНИЕ АЭРОЗОЛЬНОГО МЕЛКОДИСПЕРСНОГО СПРЕЯ ДЛЯ ПОВЫШЕНИЯ ЭФФЕКТИВНОСТИ ОХЛАЖДЕНИЯ ОРЕБРЕННЫХ ТРУБ

The article presents an overview of works on the experimental and computational study of the processes of heat removal from heated surfaces using a water-air mixture. A sharp increase in the heat transfer coefficient is shown even when adding water with a mass content of 0.1 % to the air flow. The factors that determine the efficiency of the heat exchange process are listed: the shape of the water spray jet, the distance from the outlet point of the water-air flow to the heat exchange surface, the characteristics of the heat exchange surface, the method of jet formation, the size of droplets and the location of the outlet points of the gas-droplet flow. The weak applicability of the data available in the literature is shown for calculating the cooling of finned tubes of industrial heat exchangers using a water-air mixture. It is substantiated that in order to establish the most optimal cooling modes for each for a separate heat exchange surface, it is necessary to conduct experimental studies, due to the complexity of heat transfer processes and the presence of a large number of influencing factors. It is shown that the finned tubes of heat exchangers of the passive heat removal system of WWER-1200 have a number of important features that affect the efficiency of their cooling using a water-air mixture. An experimental setup has been developed and a technique has been proposed for performing experiments to study these processes as applied to heat exchangers of a passive WWER safety system.

Experimental study on the thermal performance of a flat plate solar water collector with a bifunctional flow insert

A flat plate solar water collector is a simple solar energy conversion system for hot water production. In this experimental work, the effect of bifunctional rectangular cut flow deviator longitudinal flow inserts with a tilt angle of 30° fixed inside the absorber tube is studied with different water flow rates (0.0083, 0.0167, and 0.025 kg/s). The maximum instantaneous efficiency obtained is 72.93% at 0.025 kg/s, which is 23.6% higher than that of the conventional collector, and a lower mass flow rate results in better exergy efficiency of 3.3% at 0.0083 kg/s. The maximum instantaneous efficiency for a modified collector is observed when the outlet water temperature of 56.7 °C and the proposed flow inserts result in a maximum temperature difference of 10.5 °C between the water inlet and outlet points. The flow inserts serve as a turbulence promoter to enhance the heat transfer coefficient and the heat absorption rate of a conventional collector. The significant contribution of the flow inserts towards increasing the instantaneous efficiency of the collector confirms the bifunctionality with minimum pressure drop and pumping power. The enviro-economic analysis ensures a clean production, and solar collectors with passive inserts provide a lower payback period due to higher thermal energy output. The proposed collector's annual CO₂ mitigation and carbon credit are higher than the conventional collector, and such collectors are feasible for commercialization.

Comparison of Heat Transfer rates for Water and Ethylene Glycol mixtures for Diesel engine exhaust gas heat recovery using Shell and Tube Heat Exchanger.

Most of the researchers have claimed that high compression engines (diesel engines) are performing slightly above of 1/3rd of their potential and remaining heat energy is wasted in the form of exhaust gas. Efforts are going on to improve the design of these engines and investigations are being carried out to recover this waste energy from exhaust gases and utilize for different applications.In the present work, initially water is used as a heat exchange medium for three different loads on diesel engine viz., 50%, 60% and 70%, which extracts heat energy to evaluate the exhaust heat attainable from exhaust gases of the engine. The exhaust gas is passed through the tube side of the heat exchanger which is obtained from an exhaust manifold of a four stroke single cylinder diesel engine. Water is passed through the shell side of the shell and tube heat exchanger. Later this work is repeated for two different cooling medium i.e. water-ethylene glycol mixtures with 25% and 50%. The results are compared for 60% engine load conditions. The counter flow type heat exchanger arrangement is considered for the analysis. The temperatures were recorded for hot gases and cold medium at inlet and outlet points of the shell side and tube side flow. Heat calculations are carried out for each combination and detailed in the result–discussion and conclusion chapter. The objective of this work is to assess the exhaust gas heat recovery capacity using the ethylene glycol-water mixture and come out with a mixture for higher heat recovery capacity. This work is undertaken with segmental baffle heat exchanger of zero degree inclination. Also the work is repeated for inclined baffle heat exchangers of 10-degree and 20-degree baffle inclination to assess the effectiveness of liquid in recovering the heat from exhaust gases. It is observed that the water and Ethylene glycol mixtures have performed satisfactorily in all three baffle setups showing only 1.5% - 2.0% less heat recovery when compared with only water.

Effect of Gas Flow Rate on the Solubility and Lifetime of Liquid-Rotated Aerator Generated-Microbubbles

Ozone was adopted to be an alternative technology for the elimination of various kinds of micropollutants. However, ozonation is still limited by poor ozone dissolution in water. Microbubble technology was proposed to overcome this limitation. This paper was aimed to investigate the effect of inlet gas flow rate on the production and solubility of ozone in the liquid phase. A double dielectric barrier discharge (DDBD) -based ozone generator was used and connected to a microbubble aerator. Ozone concentration was measured both in outlet points and in water under various inlet gas flow rates. In addition, the lifetime of best-ozonated micro-bubbles (OMB) was investigated by storing them at two different temperatures. The application of a lower inlet gas flow rate increased ozone concentration, which can increase the mass of ozone input in the water resulted in better ozone solubility. Furthermore, the size of generated bubbles was known to be finer as the decrease of inlet gas flow rates. Lastly, we got that OMB water stored at lower temperatures resulted in longer retention time than the warmer one. Keywords: Ozone, gas flow rate, solubility, ozone lifetime, microbubble DOI: 10.7176/APTA/85-02 Publication date: November 30 th 2021

MONITORING OF 2-METHYLISOBORNEOL AND GEOSMINE IN A CONSTRUCTED LAKE TO PUBLIC CATCHMENT IN SOUTHERN BRAZIL

People that consumed treated water from Dourado Lake, Santa Cruz do Sul, RS, Brazil perceived alterations in its taste and odor. Based on this, we focused our study on the monitoring of 2-MIB and GSM in samples collected from Dourado Lake, using solid-phase microextraction (SPME) coupled to gas chromatography/mass spectrometry (GC/MS). The monitoring was done by performing exploratory evaluations at several points on the lake during the summers of 2017 and 2018 and in all seasons of 2019, considering points of water in an inlet and an outlet of the lake. At the inlet point, the average concentration of GSM was 7.56 ± 1.94 ng L-1 and that of 2-MIB was 33.09 ± 6.89 ng L-1. However, for the outlet point, the average concentrations of GSM and 2-MIB were 10.62 ± 2.51 ng L-1 and 28.72 ± 10.47 ng L-1, respectively. In all cases, the presence of GSM and 2-MIB was perceptible by the people consuming the water (during all seasons), showing the need for correct management of water resources.

Newly isolated coliphages for bio-controlling multidrug-resistant Escherichia coli strains

This study presents a novel coliphage-based approach for biocontrol of Multidrug-Resistant (MDR) Escherichia coli (E. coli) and coliforms in wastewater and improve the physicochemical water quality . Newly isolated coliphages and E. coli strains were isolated from the Rosetta branch of River Nile and outlet points of five associated drains. Coliphages were characterized by transmission electron microscopy and coat protein-gene analyses. The isolated coliphages PR01, PR02, and PR03 belonged to the Siphoviridae, Myoviridae, and Podoviridae families, respectively. They exhibited, separately or in a cocktail, a wide host range pattern against wild E. coli strains with higher specificity to strains isolated from drains (87%) than those of the Rosetta branch (72%). Phage-sensitive E. coli strains exhibited elevated antibiotics resistance patterns, suggesting that they are MDR strains. Interestingly, the efficacy of phages cocktail (PR01/PR02/PR03) controlled the growth of wild MDR E. coli strains and coliform populations under laboratories conditions. The kinetic trend in removal efficiency (%) for coliforms was gradually increasing in a time-dependent manner and peaked at 12 h post incubation with phages mixture. In all water samples, total and fecal coliforms revealed at least a 30-fold reduction post 12 h of treatment with a mixture of coliphages. Physicochemical analyses of phage-treated wastewater showed reducing levels in biological oxygen demand (BOD), chemical oxygen demand (COD), turbidity, electric conductivity (EC), ammonia (NH3), total dissolved solids (TDS) and nitrate (NO3), while rising in dissolved oxygen (DO) content compared to untreated wastewater. Overall, this study suggests that phage-based treatment could be an effective and cheap alternative approach for the reduction of water pollutants in drainage drainage and waste water and thus eventually enhance the physicochemical quality of water.

Prediction of Water Quality for Free Water Surface Constructed Wetland Using ANN and MLRA

Constructed wetland is commonly used as a practice to reduce non-point source pollutants and as a stormwater treatment system. For many years, the evaluation of water quality assessment for the constructed wetland is using normal sampling and laboratory work. However, in line with the technology expansion, the prediction for water quality using modelling has been developed. This study focuses on the prediction of water quality parameter for constructed wetland under tropical climate using Artificial Neural Networks (ANN) and Multiple Linear Regressions Analysis (MLRA). There are five input parameters such as water quality at the inlet point, detention time, depth of water, ratio length to width, and rainfall. The output parameters consist of the water quality at the outlet point namely Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Phosphorus (TP), Total Nitrogen (TN), and Total Suspended Solid (TSS). Squared correlation coefficient (R2) and root mean square error (RMSE) were applied to assess the model presentation and the result indicated that the ANN model shows excellent performance compared to MLRA. The R² value for each output parameter is higher than 0.90 and the RMSE values were closer to zero. However, TN has shown a very good pollutant removal in constructed wetland compared to other water quality tested. Findings from this study will contribute towards the enhancement of design performance and guideline for constructed wetlands under tropical climate.

Application of hybrid swarming algorithm on flexible job shop scheduling problems

AbstractIn this article, we present an improved hybrid algorithm based on ant colony optimization and the polycephalum algorithm. First, we use improved the probability selection mechanism in the ant colony algorithm in order to improve the efficiency of next point searching. Second, in each iteration we update the pheromone concentration of the optimal route by using the polycephalum algorithm. We regard the starting point of the optimal route as the water injection point and the end point as the water outlet point. The hybrid algorithm is compared on multiple TSPLIB problems and flexible job shop scheduling problems. And experiments show that the improved algorithm has good application results and resultful in accuracy and optimal solutions.

Design and sizing of a brewery wastewater treatment system in Douala, Cameroon: a technological solution for the protection of the environment in Sub-Saharan Africa

This article aims to design a wastewater treatment plant (WWTP) for brewery industry located in Douala-Cameroon (Central Africa) that can be applicable in Sub-Saharan Africa in similar affinity pattern. More specifically, to characterise wastewater, operate a technical choice for wastewater treatment and to design a WWTP infrastructures. Data were obtained through measurements of the flow of wastewater by the volumetric method and water quality data were collected at the outlet point of the brewery company by sampling and laboratory analysis using standard methods. The main results show that the Chemical Oxygen Demand–COD (1082 mg/l), the Biochemical Oxygen Demand–BOD5 (466 mg/l), the amount of faecal coliforms and of total coliforms (respectively, 0.99 and 6.77 million UFC/100 ml) norms in wastewater are above the Cameroonians and World Health Organisation (WHO) standards for waste disposal. The treatment technology “bacterial bed” was considered the most suitable to treat the brewery wastewater. It has a rate of flow estimated at 2700 m3 per day. The WWTP has seven components, including a sieve (meshes 0.5 cm), a deoiler (ventilation power 3400 Watts), a lamellate decanter (volume 1165 m3), a bacterial bed (cloisonyl, height 2.5 m and surface 676 m2), a second lamellate decanter with processing of calco-carbonic balance (Consumption CO2 81.07 Nm3, diameter 25 m), a bio-digester, a basin of disinfection (surface 338 m2, rate of processing 0.65 g/m3, flow of injection 12 l/h). The construction of this WWTP will enable the improvement of environmental protection around the company and hence, the city of Douala in Sub-Saharan Africa.

HYDROLOGICAL ANALYSIS OF THE WATERSHED OF AN NAJAF PROVINCE BY GIS

The analysis of the watershed gives the surface area of land that rain streamed arrived in the river. The modern method to analyze the catchment is the ArcGIS program based on the Digital Elevation Model (DEM). The study area is An Najaf province, which area equaled about 27675 square kilometers. The HECGeoHMS (Hydrologic Engineering Center's Hydrologic Modeling System) is the link program on the ArcMap software that abled by serious steps to analyze the specific watershed. The auto analysis of the watershed area gives four basins for each outlet points located on the distributary Euphrates river. These four basins consisted of multi sub-basins and streams of rain flow. Basin 4 has the most significant volume, about 11.4% of the total case area of the basin, and the average slope is 3.2%. According to the amount of accumulative rainwater, basin 4 is essential when any obstruction is constructed at the end of the outlet point in the stream. This location of the construct is used to prevent the sediment in the Euphrates river and to avoid surface soil degradation. The arrangement of importance basin based on the advantage of water using to give maximum discharge and low evaporation is basin four at the first, basin two at the second.

Flow Direction Algorithm (FDA): A Novel Optimization Approach for Solving Optimization Problems

The present study aimed to propose a new optimization algorithm named Flow Direction Algorithm (FDA), which is a physics-based algorithm. The FDA algorithm mimics the flow direction to the outlet point with the lowest height in a drainage basin. In other words, flow moves to neighbor with lowest high or best objective function. Thirteen classic mathematical benchmark functions, ten new mathematical benchmark functions and five engineering design problems, including three-bar truss, tension/compression spring, speed reducer, gear train, and welded beam design, with different properties are considered to evaluate the proposed algorithm. Comparing the results of the FDA with other optimization algorithms demonstrates the superior performance of the FDA in solving challenging optimization problems.

Subglacial discharge weakens the stability of the Ross Ice Shelf around the grounding line

In this paper, we examine potential impact of discharge in Subglacial Lake Engelhardt, West Antarctica, on the stability of the Ross Ice Shelf around the grounding line by combining satellite altimetry and remote sensing images. According to satellite altimetry data from the Ice, Cloud and Land Elevation Satellite (ICESat; 2003–06), Subglacial Lake Engelhardt (SLE) discharged ca. 1.91 ± 0.04 km3&nbsp;of water into the downstream region. The ice-surface record derived from ICESat (2006–09) and CryoSat-2 (2011–17) data shows that the lake gained ca. 2.09 ± 0.05 km3&nbsp;of water during the refilling event following the drainage event, taking three times as much time to reach the previous water level before the discharge; the calculation demonstrates that water input from an upstream lake is unable to sustain water increase in SLE, indicating that the subglacial, hydrologic system and groundwater flow could have contributed to water increase in SLE via hydrologic networks. Satellite images captured surface depressions and crevasses at the drainage outlet point of hydrologic networks around the grounding line; satellite altimetry data show that the ice surface there is still depressing even though the subglacial discharge has finished, potentially reflecting the long-term impact of subglacial discharge on the stability of the immediate Ross Ice Shelf around the grounding line.

Assessing the impact of watershed land use on Kebena river water quality in Addis Ababa, Ethiopia

BackgroundThe impact of watershed land-use on surface water quality is one of the under researched areas in mega cities of the developing countries like Addis Ababa. The study examined the impact of watershed land uses on the Kebena river water quality within its seasonal and spatial variation and assessed the relationship between river water pollution and dominant land-use types in the sub-watersheds.MethodThe main land use types in the sub-watersheds were digitized from aerial photograph of 2016, and quantified for water quality impact analysis. Water samples were collected from the main Kebena river and the three sub-watersheds source and outlet points. A total of 128 samples were collected during the dry and wet seasons of 2016 and 2017 and analyzed for various water quality parameters. The study employed ANOVA, independent t-tests and multiple regression analysis to examine variations in water quality and assess the influence of the different land uses on water quality.ResultsForest, built-up area and cultivated lands are the three major land use types in the Kebena watershed accounting for 39.14, 32.51 and 27.25% of the total area, respectively. Kebena catchment is drained by three sub-watersheds namely, Denkaka (44.9% cultivated land), Little-Kebena (60.87% forested) and Ginfle (90.44% urban land). The concentration of pollutants in the Kebena river was significantly higher (P < 0.001) in the dry season than in the wet season. However, when compared to surface water quality standards, both the dry and wet season water quality records are exceptionally high. The urban and forest dominated sub-watersheds contribute significantly high amount of (P < 0.001) pollutant loads to the river which is associated with high runoff from impervious surfaces and sewerage discharge to the river from nearby urban settlements.ConclusionIntegrating watershed planning with land use planning is of paramount importance to address water quality problems in urban areas. Thus, in the urban dominated sub-catchment, land-use planning should aim to relocating river front communities, providing sufficient river buffer-zones and forwarding appropriate storm water management schemes. In the forested sub-catchment, planning should protect, retain and enhance the existing natural green spaces through open space planning, and management schemes while providing wide river-buffer with natural vegetation cover to minimize pollution load to urban rivers from agriculture dominated sub-watershed.