Assessment of Corrosion and Scale forming Potential of Groundwater Resources: Case Study of Dire Dawa City, Ethiopia

Almost 100% of the water supply of Dire Dawa City is from groundwater (including boreholes, dug wells, and springs). Recently, groundwater cause corrosion and scale problems to water distribution systems due to its content of dissolved ions that can cause public health and economic issues. The present paper investigates the corrosion and scale-forming potential of the groundwater in the city and visualizes it with mapping. Spectrophotometer, EDTA/Acid titration with calculation methods were used for water quality parameters analysis. GW Chart Calibration plot applied for the Piper diagram to categorizes the water types. Langelier saturation (LSI), Ryznar (RSI), aggressive (AI), Puckorius Scale (PSI), and Larson-Skold (LRI) indices were manipulated with Excel ® and visualized their spatial distribution using ArcGIS 10®. The mean values of LSI, RSI, PSI, AI, and LRI obtained were 0.29 ± 0.28, 6.4 ± 0.5, 5.10 ± 0.48, 12.20 ± 0.24, and 1.4±1.57 respectively. LSI and RSI results indicate moderate to low scale-forming tendency of groundwater in most parts except the northeastern part with corrosive groundwater. Based on the AI value, the groundwater ranges low corrosion in almost all zones except the edge of the northeast and northwest region. PSI indicated the water tends to form salt-scale at a medium rate. The LSI results showed that chloride and sulphate are unlikely to interfere with the formation of protecting film except in northwestern and northeastern regions where localized corrosion might occur. In conclusion, in almost all distribution system of the city is affected by calcium carbonate scale formation. The groundwater in the northwest and northeast resulted in localized corrosion because of relatively high contents of chlorides and sulphates.

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Assessment of quality and suitability of groundwater resources for industrial and irrigation purposes, Dire Dawa, Ethiopia

Ethiopian Journal of Science and Technology ◽

10.4314/ejst.v13i3.1 ◽

1970 ◽

Vol 13 (3) ◽

pp. 161-183

Author(s):

Girmaye Haile Gebremikael ◽

Aman Hussien Dawod

Keyword(s):

Groundwater Resources ◽

Industrial Sector ◽

Localized Corrosion ◽

Sodium Absorption ◽

Corrosion Properties ◽

Mean Values ◽

Sodium Absorption Ratio ◽

Two Samples ◽

Dire Dawa ◽

Moderate Scale

The groundwater demand of Dire Dawa has increased recently due to the expansion of irrigation and the industrial sector in the city. Groundwater used for irrigation and industry was studied. Eighty-two samples were used to analyze physicochemical using different indices like Langelier index (LSI), Ryznar index (RSI), Aggressive index (AI) and Larson-Skold index (LRI). Parameters of Sodium Absorption Ratio (SAR), Residual Sodium Carbonate (RSC), Dissolved Sodium (%Na), Magnesium hazard (%Mg) statistical and spatial distributions were analyzed and programmed with Excel, Arc GIS, and Diagrams software. Results showed that pH, Mg2+, Cl- were found to be within the limit for industrial use. The groundwater corrosion indices mean values of LSI, RSI, AI, and LRI obtained were 0.29 ± 0.28, 6.4 ± 0.5, 12.20 ± 0.24 and 1.4±1.57, respectively. LSI, RSI results indicated a moderate scale-forming tendency of the groundwater. AI values were within low to no corrosion rates in all zones. Because of Cl- and SO42-, LSI showed some localized corrosion properties at kebele 01 and 09. Parameters like pH, Conductivity, Na+, HCO3- and Cl- ion were within permissible limits for irrigation. The irrigation indices (meq/l); SAR, RCS, Na% and Mg Hazard were calculated to be 1.33, -2.17, 21.5%, 45%, respectively. The EC was within the permissible limit but was significant. The low values of SAR, RCS, Na% indicated that the groundwater can cause lower alkalization (Sodium hazard) effect. In conclusion, all the parameters of the groundwater sources were categorized as good for irrigation. However, corrosion indices elaborated the groundwater scaling problems and may also be aggravated with temperature and heat-related industrial equipment.

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The 1906 Earthquake Impacts on the San Francisco and Santa Clara Water Systems—What we Learned, and What we are doing about It

Earthquake Spectra ◽

10.1193/1.2186986 ◽

2006 ◽

Vol 22 (2_suppl) ◽

pp. 113-134 ◽

Cited By ~ 2

Author(s):

John Eidinger ◽

Lota de Castro ◽

Dennis Ma

Keyword(s):

San Francisco ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Cost Effective ◽

System Operator ◽

Water Transmission ◽

Pump Stations ◽

Transmission And Distribution ◽

The City

This paper describes what happened to San Francisco's water transmission and the city of Santa Clara's water distribution systems in the 1906 and the 1989 earthquakes. These two earthquakes showed that many of our existing transmission and distribution pipelines are susceptible to damage, and some of our older water treatment plants, tanks, and pump stations need to be upgraded. Accordingly, seismic upgrade programs are being undertaken to reduce the vulnerability of the regional water transmission and distribution systems. In developing a cost effective seismic upgrade program, both the transmission system operator (San Francisco Public Utilities Commission) (SFPUC) and distribution system operator (Santa Clara) consider what the weaknesses are of both systems, so that the maximum amount of seismic upgrade can be achieved at the lowest overall cost.

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Application of genetic programming to modeling pipe failures in water distribution systems

Journal of Hydroinformatics ◽

10.2166/hydro.2010.189 ◽

2010 ◽

Vol 13 (3) ◽

pp. 419-428 ◽

Cited By ~ 12

Author(s):

Qiang Xu ◽

Qiuwen Chen ◽

Weifeng Li

Keyword(s):

Genetic Programming ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Pipe Failure ◽

Beijing City ◽

Failure Data ◽

Processing Strategies ◽

Gis Data ◽

Failure Models

The water loss from a water distribution system is a serious problem for many cities, which incurs enormous economic and social loss. However, the economic and human resource costs to exactly locate the leakage are extraordinarily high. Thus, reliable and robust pipe failure models are demanded to assess a pipe's propensity to fail. Beijing City was selected as the case study area and the pipe failure data for 19 years (1987–2005) were analyzed. Three different kinds of methods were applied to build pipe failure models. First, a statistical model was built, which discovered that the ages of leakage pipes followed the Weibull distribution. Then, two other models were developed using genetic programming (GP) with different data pre-processing strategies. The three models were compared thereafter and the best model was applied to assess the criticality of all the pipe segments of the entire water supply network in Beijing City based on GIS data.

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A Head Formulation for the Steady-State Analysis of Water Distribution Systems Using an Explicit and Exact Expression of the Colebrook–White Equation

Water ◽

10.3390/w13091163 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1163

Author(s):

Mengning Qiu ◽

Avi Ostfeld

Keyword(s):

Steady State ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Solution Method ◽

Water Distribution System ◽

Academic Research ◽

Exact Expression ◽

Contamination Source

Steady-state demand-driven water distribution system (WDS) solution is the bedrock for much research conducted in the field related to WDSs. WDSs are modeled using the Darcy–Weisbach equation with the Swamee–Jain equation. However, the Swamee–Jain equation approximates the Colebrook–White equation, errors of which are within 1% for ϵ/D∈[10−6,10−2] and Re∈[5000,108]. A formulation is presented for the solution of WDSs using the Colebrook–White equation. The correctness and efficacy of the head formulation have been demonstrated by applying it to six WDSs with the number of pipes ranges from 454 to 157,044 and the number of nodes ranges from 443 to 150,630. The addition of a physically and fundamentally more accurate WDS solution method can improve the quality of the results achieved in both academic research and industrial application, such as contamination source identification, water hammer analysis, WDS network calibration, sensor placement, and least-cost design and operation of WDSs.

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Cyber—Physical Attack Detection in Water Distribution Systems with Temporal Graph Convolutional Neural Networks

Water ◽

10.3390/w13091247 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1247

Author(s):

Lydia Tsiami ◽

Christos Makropoulos

Keyword(s):

Neural Networks ◽

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Attack Detection ◽

Convolutional Network ◽

Irreversible Damage ◽

Physical Attack ◽

Temporal Graph ◽

Graph Neural Networks

Prompt detection of cyber–physical attacks (CPAs) on a water distribution system (WDS) is critical to avoid irreversible damage to the network infrastructure and disruption of water services. However, the complex interdependencies of the water network’s components make CPA detection challenging. To better capture the spatiotemporal dimensions of these interdependencies, we represented the WDS as a mathematical graph and approached the problem by utilizing graph neural networks. We presented an online, one-stage, prediction-based algorithm that implements the temporal graph convolutional network and makes use of the Mahalanobis distance. The algorithm exhibited strong detection performance and was capable of localizing the targeted network components for several benchmark attacks. We suggested that an important property of the proposed algorithm was its explainability, which allowed the extraction of useful information about how the model works and as such it is a step towards the creation of trustworthy AI algorithms for water applications. Additional insights into metrics commonly used to rank algorithm performance were also presented and discussed.

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Comparison of Searching Behaviour of Three Evolutionary Algorithms Applied to Water Distribution System Design Optimization

Water ◽

10.3390/w12030695 ◽

2020 ◽

Vol 12 (3) ◽

pp. 695 ◽

Cited By ~ 2

Author(s):

Weiwei Bi ◽

Yihui Xu ◽

Hongyu Wang

Keyword(s):

Evolutionary Algorithms ◽

Real Time ◽

Distribution System ◽

Optimization Design ◽

Distribution Systems ◽

Water Distribution ◽

Optimal Solutions ◽

Great Ability ◽

Searching Behaviour ◽

Run Time

Over the past few decades, various evolutionary algorithms (EAs) have been applied to the optimization design of water distribution systems (WDSs). An important research area is to compare the performance of these EAs, thereby offering guidance for the selection of the appropriate EAs for practical implementations. Such comparisons are mainly based on the final solution statistics and, hence, are unable to provide knowledge on how different EAs reach the final optimal solutions and why different EAs performed differently in identifying optimal solutions. To this end, this paper aims to compare the real-time searching behaviour of three widely used EAs, which are genetic algorithms (GAs), the differential evolution (DE) algorithm and the ant colony optimization (ACO). These three EAs are applied to five WDS benchmarking case studies with different scales and complexities, and a set of five metrics are used to measure their run-time searching quality and convergence properties. Results show that the run-time metrics can effectively reveal the underlying searching mechanisms associated with each EA, which significantly goes beyond the knowledge from the traditional end-of-run solution statistics. It is observed that the DE is able to identify better solutions if moderate and large computational budgets are allowed due to its great ability in maintaining the balance between the exploration and exploitation. However, if the computational resources are rather limited or the decision has to be made in a very short time (e.g., real-time WDS operation), the GA can be a good choice as it can always identify better solutions than the DE and ACO at the early searching stages. Based on the results, the ACO performs the worst for the five case study considered. The outcome of this study is the offer of guidance for the algorithm selection based on the available computation resources, as well as knowledge into the EA’s underlying searching behaviours.

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Modelling both the continual erosion and regeneration of discolouration material in drinking water distribution systems

Water Science & Technology Water Supply ◽

10.2166/ws.2013.176 ◽

2013 ◽

Vol 14 (1) ◽

pp. 81-90 ◽

Cited By ~ 13

Author(s):

W. R. Furnass ◽

R. P. Collins ◽

P. S. Husband ◽

R. L. Sharpe ◽

S. R. Mounce ◽

...

Keyword(s):

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Transport Model ◽

Water Distribution Systems ◽

Sensitivity Analyses ◽

Drinking Water Distribution Systems ◽

Proactive Management ◽

Drinking Water Distribution ◽

Mass Transport Model

The erosion of the cohesive layers of particulate matter that causes discolouration in water distribution system mains has previously been modelled using the Prediction of Discolouration in Distribution Systems (PODDS) model. When first proposed, PODDS featured an unvalidated means by which material regeneration on pipe walls could be simulated. Field and laboratory studies of material regeneration have yielded data that suggest that the PODDS formulations incorrectly model these processes. A new model is proposed to overcome this shortcoming. It tracks the relative amount of discolouration material that is bound to the pipe wall over time at each of a number of shear strengths. The model formulations and a mass transport model have been encoded as software, which has been used to verify the model's constructs and undertake sensitivity analyses. The new formulations for regeneration are conceptually consistent with field and laboratory observed data and have potential value in the proactive management of water distribution systems, such as evaluating change in discolouration risk and planning timely interventions.

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Dynamic updating of post-earthquake damage and functional restoration forecasts of water distribution systems using Bayesian inferencing

Earthquake Spectra ◽

10.1177/87552930211038016 ◽

2021 ◽

pp. 875529302110380

Author(s):

Agam Tomar ◽

Henry V Burton ◽

Ali Mosleh

Keyword(s):

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Epistemic Uncertainty ◽

Discrete Event ◽

Complete Recovery ◽

Current Data ◽

Functional Restoration ◽

Mitigation Measures ◽

Total Recovery

A framework for dynamically updating post-earthquake functional recovery forecasts is presented to reduce the epistemic uncertainty in the predictive model. A Bayesian Network (BN) model is used to provide estimates of the total recovery time, and a process-based discrete event simulation (PBDES) model generates forecasts of the complete recovery trajectory. Both models rely on component damage and duration-based input parameters that are dynamically updated using Bayes’ theorem, as information becomes available throughout the recovery process. The effectiveness of the proposed framework is demonstrated through an application to the pipe network of the City of Napa water distribution system. More specifically, pipe damage and repair data from the 2014 earthquake are used as a point of comparison for the dynamic forecasts. It is shown that, over time, the mean value of the total recovery duration generated by the BN-based model converges to the observed value and the dispersion is reduced. Also, despite a crude initial estimate, the median trajectory generated by the PBDES model provides a reasonable approximation of the observed recovery within 30 days following the earthquake. The proposed framework can be used by emergency managers to investigate the efficacy of post-event mitigation measures (e.g. crew allocation, resource prioritization) utilizing the most current data and knowledge.

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Drinking Water Fluoride Levels for a City in Northern Mexico (Durango) Determined Using a Direct Electrochemical Method and Their Potential Effects on Oral Health

The Scientific World JOURNAL ◽

10.1155/2013/186392 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Nelly Molina Frechero ◽

Leonor Sánchez Pérez ◽

Enrique Castañeda Castaneira ◽

Anastasio Oropeza Oropeza ◽

Enrique Gaona ◽

...

Keyword(s):

Drinking Water ◽

Distribution System ◽

Water Distribution ◽

Dental Fluorosis ◽

Fluoride Concentration ◽

Mean Value ◽

National Standard ◽

Preventative Measures ◽

The Government ◽

The City

Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations >0.7 parts per million (ppm), consuming such water can be toxic to the human body; this toxicity is called “fluorosis.” Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189) water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313 ± 1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001 ± 2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen.

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Design of Water Distribution System: Appropriateness of Structured System in Large Irrigation Projects in Nepal

Hydro Nepal Journal of Water Energy and Environment ◽

10.3126/hn.v19i0.15348 ◽

2016 ◽

Vol 19 ◽

pp. 25-30

Author(s):

Basistha Adhakari

Keyword(s):

Distribution System ◽

Distribution Systems ◽

Water Distribution ◽

Irrigation System ◽

Command Area ◽

Irrigation Project ◽

Irrigation Projects ◽

Structured System ◽

Large Irrigation ◽

Area Development

Many large irrigation projects in Nepal operate under command area development works that emphasize on-farm water distribution and management. These projects have specific design characteristics that were planned to comply with available water resources, climatic conditions, soil type, and water distribution technology. The water distribution technologies differ based on the design needs of each individual project and the design preferences of various foreign consulting firms. This article focuses on the issues of planning and designing water distribution systems of large irrigation systems at the irrigation service delivery level. The layout planning of an irrigation system is an important aspect of design for water distribution, typically guided by hierarchical system. This article also highlights the existing canal hierarchy of these systems and their appropriateness for efficient water distribution. Furthermore, the appropriateness of the structured system is also examined in the Sunsari Morang Irrigation Project. The article concluded with some suggestions for planning and designing command area development works of forthcoming large irrigation projects such as the Sikta Irrigation Project, the Babai Irrigation Project, and the Mahakali Irrigation Project Stage-III.HYDRO Nepal JournalJournal of Water, Energy and EnvironmentIssue: 19Page: 25-30

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