EVALUATING DRAINAGE DESIGN PARAMETERS FOR WASTEWATER IRRIGATION APPLICATIONS TO MINIMIZE IMPACT ON SURFACE WATERS

Aimed at the feature of expressway subgrade drainage facilities in typical red sandstone areas in Jiangxi province and based on the importance of the structure, damage conditions, service requirements and the current specification requirements related to various types of ditches, the designed repetition period of rainfall and proposed safety depth values for drainage facilities were put forward by considering reasonably the key design parameters to regional drainage facilities. The relationship between prerequisite of discharging sediment in ditches or conduits and minimum longitudinal gradient was discussed. Combined with the characteristics of red sandstone subgrade drainage with high requirements, the design elements of red sandstone area expressway subgrade drainage system were obtained, which can provide beneficial references for the subgrade drainage design in red sandstone areas.

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Calibration of DRAINMOD for prediction of water table depths and drain discharges under waterlogged Vertisols of Maharashtra, India

Journal of Applied and Natural Science ◽

10.31018/jans.v11i3.2142 ◽

2019 ◽

Vol 11 (3) ◽

pp. 724-731

Author(s):

Shrimant Rathod ◽

Sudhir Dahiwalkar ◽

Sunil Gorantiwar ◽

Mukund Shinde

Keyword(s):

Water Table ◽

Agricultural Research ◽

Drainage System ◽

Subsurface Drainage ◽

Design Parameters ◽

Design System ◽

Research Station ◽

Drain Spacing ◽

Drainage Design ◽

Rainy Days

An estimation of optimal design parameters of subsurface drainage system through monitoring of water table depths and drain discharges are expensive in terms of time and money. The simulation modeling is an effective tool for estimation of drainage design parameters at less cost and short time. In view to this, calibration of DRAINMOD model for prediction of water table depths and drain discharges were conducted by installing subsurface drainage system with 40 m drain spacing and 1.0 m drain depth at Agricultural Research Station, Kasbe Digraj, Dist. Sangli (Maharashtra) during 2012-13 to 2013-14. The field data on water table depth and drain discharge were used for calibration of DRAINMOD model. The input data files on climatic, soil, crop and drainage design system parameters were attached to DRAINMOD model and calibrated successfully. It is found that both observed and simulated water table depths and drain discharges showed a fluctuating trend and predicted both water table depths and drain discharges closely with the observed values during frequent rainy days and following the rainy days. The DRAINMOD model reliably predicted water table depths with a goodness of fit (R2 = 0.97), MAE (12.23 cm), RMSE (15.49 cm) and CRM (0.05); drain discharges with R2 of 0.93, MAE of 0.095 mm day-1, RMSE of 0.1876 mm day-1and CRM of 0.04. Thus, the calibrated DRAINMOD model can be used to simulate the water table depths and drain discharges in semi-arid climatic conditions of Maharashtra and in turn to estimate and evaluate drain spacing and depth.

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State of the Art Review: An Epidemiological Approach to the Health Effects of Wastewater Reuse

Water Science & Technology ◽

10.2166/wst.1986.0087 ◽

1986 ◽

Vol 18 (9) ◽

pp. 147-162 ◽

Cited By ~ 7

Author(s):

H. I. Shuval ◽

B. Fattal ◽

P. Yekutiel

Keyword(s):

Surface Waters ◽

Pathogenic Bacteria ◽

Wastewater Reuse ◽

Epidemiological Studies ◽

Wastewater Irrigation ◽

Effective Control ◽

Wastewater Stream ◽

Medium Risk ◽

Potential Risks ◽

Health Regulations

The reuse of wastewaters for agricultural irrigation can be a means of reducing the pollution of surface waters including those in coastal areas used for bathing. The wastewater stream of a community carries within it the complete spectrum of pathogenic bacteria, viruses, protozoa and helminths which are endemic in the community. These pathogens can survive sufficiently long in the soil or on crops to infect, at least in theory, persons coming in direct contact. Thus, it is important to establish a sound epidemiological basis for health regulations related to the reuse of wastewater in agriculture. This paper presents the theoretical epidemiological considerations that should serve as the basis for a predictive model of the potential risks associated with wastewater irrigation. Empirical data from credible, quantifiable epidemiological studies have here been reviewed to validate the theoretical model. For developing countries, the authors have concluded that the ranking of pathogens as to the degree of risk associated with wastewater irrigation is as follows: high risk - helminths, medium risk - bacteria and protozoa and low risk - viruses.In order to effectively reduce the concentration of these pathogens wastewater treatment is recommended as the most effective control strategy.

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Simulating Effects of Drainage Design Parameters on Optimum Crop Yield Using DRAINMOD

10.13031/2013.35743 ◽

2010 ◽

Author(s):

Temitayo Abayomi Ewemoje ◽

Oluwaseun Kunle Oyebode ◽

Olayiwola Akin Akintola ◽

Oluseyi Elizabeth Ewemoje

Keyword(s):

Crop Yield ◽

Design Parameters ◽

Drainage Design

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Modeling Tile Drainage Outflow in Thin Agricultural Soils with Impermeable under Layer in Newfoundland and Labrador, Canada

Advances in Environmental and Engineering Research ◽

10.21926/aeer.2102016 ◽

2020 ◽

Vol 02 (02) ◽

pp. 1-1

Author(s):

Lordwin Girish Kumar Jeyakumar ◽

◽

David B. McKenzie ◽

Yuanmei Zhang ◽

Lakshman Galagedara ◽

...

Keyword(s):

Water Table ◽

Newfoundland And Labrador ◽

Agricultural Soils ◽

Subsurface Drainage ◽

Tile Drainage ◽

Design Parameters ◽

Podzolic Soils ◽

Drainage Design ◽

Water Outflow ◽

Avalon Peninsula

Subsurface tile drainage installation helps to maintain water table levels and to meet adequate crop moisture requirements. Artificial subsurface drainage continues to be a common practice in Newfoundland and Labrador (NL) and elsewhere around the world. The main objective of this study was to evaluate the performance of DRAINMOD in simulating water table depth (WTD) and water outflow from tile drained agricultural fields. This site on the Avalon Peninsula of Eastern Newfoundland has a rolling landscape with predominantly Podzolic soils. The tile drainage was installed at 1.0 m deep and spaced 12 m apart. Drainage outflows (two per plot) from twelve experimental plots (32 m x 60 m each) were monitored for two years. The simulated WTD ranged from 140 cm to 160 cm during rainfall season. The performance of the model was evaluated by the Index of agreement (IOA). It was 0.600 in 2017 and 0.559 in 2018. The result was considered to have acceptable accuracy, which can help to design or evaluate subsurface drainage systems in NL, Canada. However, further evaluation including additional sites are necessary to ensure optimum drainage design parameters for the major agricultural soils.

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Habitat Association of Klebsiella Species

Infection Control ◽

10.1017/s0195941700062603 ◽

1985 ◽

Vol 6 (2) ◽

pp. 52-58 ◽

Cited By ~ 111

Author(s):

Susan T. Bagley

Keyword(s):

Drinking Water ◽

Gastrointestinal Tract ◽

Surface Waters ◽

Industrial Effluents ◽

Opportunistic Pathogen ◽

Habitat Associations ◽

Habitat Association ◽

Klebsiella Species ◽

Almost All ◽

Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

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Identifying Sources of Sulfate Aerosols Reaching Whiteface Mountain, NY

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117546 ◽

1985 ◽

Vol 43 ◽

pp. 98-101

Author(s):

James S. Webber

Keyword(s):

Trace Metals ◽

Acid Deposition ◽

Surface Waters ◽

Dry Deposition ◽

Coal Combustion ◽

Public Awareness ◽

Sulfate Aerosols ◽

Wet And Dry Deposition ◽

Whiteface Mountain ◽

Toxic Trace Metals

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.

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The influence of confocal microscope design on imaging performance

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146564 ◽

1993 ◽

Vol 51 ◽

pp. 144-145

Author(s):

C J R Sheppard

Keyword(s):

Image Quality ◽

Fluorescence Imaging ◽

Confocal Microscope ◽

Industrial Applications ◽

Three Dimensions ◽

Design Parameters ◽

Weak Signals ◽

Size And Shape ◽

Imaging Performance ◽

Fundamental Limitation

The confocal microscope is now widely used in both biomedical and industrial applications for imaging, in three dimensions, objects with appreciable depth. There are now a range of different microscopes on the market, which have adopted a variety of different designs. The aim of this paper is to explore the effects on imaging performance of design parameters including the method of scanning, the type of detector, and the size and shape of the confocal aperture.It is becoming apparent that there is no such thing as an ideal confocal microscope: all systems have limitations and the best compromise depends on what the microscope is used for and how it is used. The most important compromise at present is between image quality and speed of scanning, which is particularly apparent when imaging with very weak signals. If great speed is not of importance, then the fundamental limitation for fluorescence imaging is the detection of sufficient numbers of photons before the fluorochrome bleaches.

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