Water quality in a small network - problems and a proposal for their solution

2009 ◽  
Vol 4 (3) ◽  
Author(s):  
D. Kowalski

The paper deals with the problem of deterioration of water quality in water supply networks. On the basis of relevant literature and his own research, the author points to a common occurrence of this phenomenon. The case study of a 3.5 km town network presented in the paper confirms the situation. The field tests of the water quality in that network detected a high concentration of iron and presence of lead contamination from PVC pipes. One of the methods of counteracting water quality deterioration used by water companies is flushing, accomplished as water outflow by fire hydrants. Unfortunately this method has several disadvantages, such as substantial water loss and the resulting costs. These factors dictate limitation of the flushing frequency as well of the duration of the process. In addition, the house pipes are not flushed at all. As a conceptual solution to this problem the author proposes, is the implementation of mobile flushing stations. The closed cycle applied during the flushing process can essentially reduce the water loss. The proposed solution has been tested by computer simulations. A simplified cost estimation of the implementation of the solution has also been presented.

Author(s):  
Keizo Negi ◽  
Keizo Negi ◽  
Takuya Ishikawa ◽  
Takuya Ishikawa ◽  
Kenichiro Iba ◽  
...  

Japan experienced serious water pollution during the period of high economic growth in 1960s. It was also the period that we had such damages to human health, fishery and living conditions due to red tide as much of chemicals, organic materials and the like flowing into the seas along the growing population and industries in the coastal areas. Notable in those days was the issues of environment conservation in the enclosed coastal seas where pollutants were prone to accumulate inside due to low level of water circulation, resulting in the issues including red tide and oxygen-deficient water mass. In responding to these issues, we implemented countermeasures like effluent control with the Water Pollution Control Law and improvement/expansion of sewage facilities. In the extensive enclosed coastal seas of Tokyo Bay, Ise Bay and the Seto Inland Sea, the three areas of high concentration of population, we implemented water quality total reduction in seven terms from 1979, reducing the total quantities of pollutant load of COD, TN and TP. Sea water quality hence has been on an improvement trend as a whole along the steady reduction of pollutants from the land. We however recognize that there are differences in improvement by sea area such as red tide and oxygen-deficient water mass continue to occur in some areas. Meanwhile, it has been pointed out that bio-diversity and bio-productivity should be secured through conservation/creation of tidal flats and seaweed beds in the view point of “Bountiful Sea” To work at these challenges, through the studies depending on the circumstances of the water environment in the enclosed coastal seas, we composed “The Policy of Desirable State of 8th TPLCS” in 2015. We have also added the sediment DO into the water quality standard related to the life-environmental items in view of the preservation of aquatic creatures in the enclosed water areas. Important from now on, along the Policy, is to proceed with necessary measures to improve water quality with good considerations of differences by area in the view point of “Beautiful and bountiful Sea”.


2021 ◽  
Vol 11 (7) ◽  
Author(s):  
H. J. Surendra ◽  
B. T. Suresh ◽  
T. D. Ullas ◽  
T. Vinayak ◽  
Vinay P. Hegde

AbstractWater companies and their consumers affected with leakages in water distribution system worldwide. This has attracted many practitioner’s attention as well as researchers over the past years. Selected study area suffers from water losses of about 10 to 15% which accounts to loss of about 9 to 9.75 million liters per month. The present study was under taken to understand, analyze and evaluate the losses and suggest preventive measures of wrapping and repair clamping for control of these losses. The assessment of water losses is done through comparative analysis of data using Microsoft Excel software. Population forecasting is done in context of assessing the amount of water lost that can be prevented in future decades, adjusting to increased water demand and losses. For better efficiency of the suggested methods, experimental analysis was carried out on a reduced scale model of a single stretched pipeline. Cost estimation of the preventive measures was done by obtaining information about the materials used by trading professionals.


2019 ◽  
Vol 374 (1784) ◽  
pp. 20190203 ◽  
Author(s):  
Kenan P. Fears ◽  
Andrew Barnikel ◽  
Ann Wassick ◽  
Heonjune Ryou ◽  
Janna N. Schultzhaus ◽  
...  

Concerns about the bioaccumulation of toxic antifouling compounds have necessitated the search for alternative strategies to combat marine biofouling. Because many biologically essential minerals have deleterious effects on organisms at high concentration, one approach to preventing the settlement of marine foulers is increasing the local concentration of ions that are naturally present in seawater. Here, we used surface-active borate glasses as a platform to directly deliver ions (Na + , Mg 2+ and BO 4 3− ) to the adhesive interface under acorn barnacles ( Amphibalanus ( =Balanus ) amphitrite ). Additionally, surface-active glasses formed reaction layers at the glass–water interface, presenting another challenge to fouling organisms. Proteomics analysis showed that cement deposited on the gelatinous reaction layers is more soluble than cement deposited on insoluble glasses, indicating the reaction layer and/or released ions disrupted adhesion processes. Laboratory experiments showed that the majority (greater than 79%) of adult barnacles re-attached to silica-free borate glasses for 14 days could be released and, more importantly, barnacle larvae did not settle on the glasses. The formation of microbial biofilms in field tests diminished the performance of the materials. While periodic water jetting (120 psi) did not prevent the formation of biofilms, weekly cleaning did dramatically reduce macrofouling on magnesium aluminoborate glass to levels below a commercial foul-release coating. This article is part of the theme issue ‘Transdisciplinary approaches to the study of adhesion and adhesives in biological systems’.


2011 ◽  
Vol 1 (1) ◽  
pp. 68-85 ◽  
Author(s):  
Patty Chuang ◽  
Stephanie Trottier ◽  
Susan Murcott

The UN defines water supplies as ‘improved’ or ‘unimproved.’ These indicators are easy to measure, but do not reflect water quality, which requires laboratory or field tests. Laboratory and test availability, expense and technical capacity are obstacles for developing countries. This research compares and verifies four low-cost, field-based microbiological tests: the EC-Kit (Colilert® and Petrifilm™ tests), the H2S bacteria test, and Easygel®, against a standard method (Quanti-Tray®). The objectives are to: (1) verify the accuracy of the four field-based tests, (2) study the accuracy of these tests as a function of improved and unimproved sources; (3) recommend a single microbiological test, if appropriate, based on accuracy and cost, and/or (4) recommend a testing combination, if appropriate, based on accuracy and cost. The tests of 500+ total water samples from Capiz Province, Philippines and Cambridge, MA indicate that two-tests systems gave better results than a single test. Both the 100-mL H2S test + Petrifilm™ and the 20-mL H2S test + Easygel® combinations yield promising results, in addition to being inexpensive. None of the field-based tests should be used on their own. We recommend further verification of a larger sample size and scale be undertaken before these testing combinations are recommended for wider use.


Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1321 ◽  
Author(s):  
Muhammad Aleem ◽  
Cao Shun ◽  
Chao Li ◽  
Arslan Aslam ◽  
Wu Yang ◽  
...  

The industrial augmentation and unguided anthropogenic activities contaminate water sources in most parts of the world especially in developing countries like Pakistan. High concentration of pollutants in groundwater affects human, soil, and crop health badly. The present study was conducted to investigate groundwater quality for drinking and irrigation purposes in an industrial zone of Pakistan. A GIS tool was used to investigate the spatial distribution of different physico-chemical parameters. In this study, the average results exceeding World Health Organization (WHO) and National Environmental Quality Standards (NEQS) were found for pH 7.84, total dissolved solids (TDS) 1492 mg/L, phosphate 0.51 mg/L, dissolved oxygen (DO) 9.92% saturation, F-coli 6.48 colonies/100 mL, Na+ 366 mg/L, HCO3− 771 mg/L, sulfate 251 mg/L, chlorides 427 mg/L, total hardness (as CaCO3) 292 mg/L, electrical conductivity (EC) 2408 μS/cm, iron (Fe) 0.48 mg/L, chrome (Cr) 0.50 mg/L, arsenic (As) 0.04 mg/L, total phosphorus (TP) 0.17 mg/L, sodium adsorption ratio (SAR) 9.76 (in meq/L), residual sodium carbonate (RSC) 9.28 meq/L, % ion balance 14.4 (in meq/L), percentage sodium ion (% Na+) concentration 58.9 meq/L, and water quality index (WQI) 69.0. The trend of cations and anions were (in meq/L) Na > Mg > Ca > K and HCO3 > Cl > CO3 > SO4 respectively. Although the results of the present study showed poor conditions of the groundwater for drinking as WQI but and irrigation purposes as SAR, it needs to improve some more conditions for the provision of safe drinking water and irrigation water quality.


1970 ◽  
Vol 9 ◽  
pp. 143-148 ◽  
Author(s):  
Rajendra K. Mahat ◽  
Rashmi Shrestha

Drinking water quality in Nepal has been an issue of prevalent concern. So, this study was conducted to visualize the scenario of metal contamination in ground water of Dang district located at central west Terai in Nepal. A total of 523 water samples from tubewells and dugwells positioned in 16 village development committees (VDCs) were tested for arsenic in laboratory using atomic absorption spectrophotometer (AAS) employing continuous flow hydride generation technique. Randomly selected 20 samples were also tested for other heavy and trace metals like Mn, Fe, Cu, and Cd using AAS employing flame method. Of the total samples, 50.3% was found to contain arsenic above WHO drinking water qualty guidelines value of 10 ppb (0.01 mg/l) and 10.7% was found to contain arsenic above national drinking water quality guidelines value of 50 ppb (0.05 mg/l). The safest VDC is Sonpur while the most severely affected VDC is Gobardiha. A highest concentration of As of 240 ppb (0.24 mg/ l) was found in Dhikpur VDC. Ground water in this area seemed to be affected by high concentration of iron up to 11.01 mg/l and of manganese up to 0.51 mg/L. Statistical tools were employed to assess the probable association among metals but no significant correlation could be retrieved. Key words: hydride generation-atomic absorption spectrophotometry; redox conversion; arsenicosis; heavy and trace metals DOI: 10.3126/njst.v9i0.3178 Nepal Journal of Science and Technology 9 (2008) 143-148


2013 ◽  
Vol 316-317 ◽  
pp. 599-605
Author(s):  
Feng Qian ◽  
Wei Lin ◽  
Bo Hu ◽  
Jing Jun Liu ◽  
Ming Biao Xiong

“5.12 Wenchuan earthquake”triggered floods, landslide, collapse and secondary geological disaster, trigger a new soil and water loss, having the significant influence to the local river water quality.This article through the statistical analysis of minjiang river and jiangyou wenchuan, beichuan station 2006 ~ 2011 water conditions material, discussing the before and after the earthquake disaster areas of river water quality change characteristics. The results showed From ammonia nitrogen source analysis, urban sewage and industrial waste water, agricultural non-point source pollution and earthquake that triggered the new soil and water loss is the main pollution source. Based on the hydrological site total hardness concentration prediction, we can find wenchuan earthquake disaster area total hardness concentration significantly increase trend.


2021 ◽  
Vol 23 ◽  
pp. 318-331
Author(s):  
Aleksandra Czajkowska ◽  
Łukasz Gawor

In the paper there is presented an evaluation of variability of surface water quality (reservoirs and watercourses), on the area of degraded post-mining area in Bytom. The physicochemical analysis of water and compared with archival data obtained in 2009 and 2014. There were done analysis of following parameters: reaction, total content of substances dissolved in water, water hardness and the content of: Cl-, SO42-, HCO3-, Ca2+, Mg2+, K+, Na+, NH4+, NO3-, NO2-, PO4- ions as well as Fe and Mn. The examined surface waters were characterised by high content of solutes. Anions were dominated by chlorides, the sodium proved to be the dominating cation, the examined water samples were characterised by high concentration of sulphates. In all analyzed reservoirs, permissible concentrations of chlorides and sulphates were exceeded. In all sample points there was observed a decrease of pH value in long term period, the concentration of chlorides lowered, however concentrations of sulphates increased in the majority of sampling points.


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