Common Water Source Research Articles

Transboundary water management Game-theoretic lessons for projects on the US-Mexico border

Of the twelve million people who live within 100 km of the US–Mexico border, 90 percent are clustered in transboundary sister cities that share common water sources and pollution problems. New institutions created to address environmental concerns over NAFTA offer the promise of greater financial and technical assistance for water management in border cities. This paper reviews US–Mexico border water issues and institutions. Using insights from game theory, it draws policy lessons for institutions funding border water projects. We examine how the design of assistance programs, technical support, and pre-existing water rights and regulations affect project outcomes. The diversity and geographic dispersion of water conflicts suggests potential for applying the interconnected game approach to US-Mexico water negotiations.

Transboundary water management Game-theoretic lessons for projects on the US–Mexico border

Of the twelve million people who live within 100 km of the US‐Mexico border, 90 percent are clustered in transboundary sister cities that share common water sources and pollution problems. New institutions created to address environmental concerns over NAFTA offer the promise of greater financial and technical assistance for water management in border cities. This paper reviews US‐Mexico border water issues and institutions. Using insights from game theory, it draws policy lessons for institutions funding border water projects. We examine how the design of assistance programs, technical support, and pre-existing water rights and regulations affect project outcomes. The diversity and geographic dispersion of water conflicts suggests potential for applying the interconnected game approach to US‐Mexico water negotiations. © 2000 Elsevier Science B.V. All rights reserved. JEL classification: Q250 — Renewable Resources and Conservation, Environmental Management: Water, Air, Climate; Q280 — Renewable Resources and Conservation, Environmental Management: Government Policy; D740 — Conflict, Conflict Resolution; D780 — Positive Analysis of Policy-Making and Implementation

Microbial quality of water in rural communities of Trinidad.

A cross-sectional study was conducted in four rural communities of northeastern Trinidad to determine the microbial quality of water supply to households and that quality's relationship to source and storage device. Of the 167 household water samples tested, total coliforms were detected in 132 of the samples (79.0%), fecal coliforms in 102 (61.1%), and E. coli in 111 (66.5%). There were significant differences among the towns in the proportion of the samples contaminated with coliforms (P < 0.001) and E. coli (P < 0.001). Of 253 strains of E. coli studied, 4 (1.6%) were mucoid, 9 (3.6%) were hemolytic, and 37 (14.6%) were nonsorbitol fermenters. Of 69 isolates of E. coli tested, 10 (14.5%) were verocytotoxigenic. Twenty-eight (14.0%) of 200 E. coli isolates tested belonged to enteropathogenic serogroups. Standpipe, the most common water source, was utilized by 57 (34.1%) of the 167 households. Treated water (pipeborne in homes, standpipes, or truckborne) was supplied to 119 households (71.3%), while 48 households (28.7%) used water from untreated sources (rain, river/stream, or well) as their primary water supply. The type of household storage device was associated with coliform contamination. Water stored in drums, barrels, or buckets was more likely to harbor fecal coliforms (74.2% of samples) than was water stored in tanks (53.3% of samples), even after controlling for water source (P = 0.04). Compared with water from other sources, water piped into homes was significantly less likely to be contaminated with total coliforms (56.9% versus 88.8%, P < 0.001) and fecal coliforms (41.2% versus 69.8%, P < 0.01), even when the type of storage device was taken into account. However, fecal contamination was not associated with whether the water came from a treated or untreated source. We concluded that the drinking water in rural communities in Trinidad was grossly unfit for human consumption, due both to contamination of various water sources and during household water storage.

Village level risk factors for foot-and-mouth disease in Northern Thailand

A study was undertaken in northern Thailand to identify factors which put some villages at higher risk of foot-and-mouth disease (FMD) outbreaks than others. The number of FMD outbreaks experienced in the previous 5 years and data on 145 putative risk factors were obtained by interview from 60 villages during 1991–1992. Univariable analyses identified 27 factors for further investigation using logistic regression. When villages were classified into three FMD frequency groups of zero to one, two to three or four or more outbreaks in the last 5 years, the important factors explaining the differences in risk were the total number of cattle and buffaloes purchased in the previous year, the number of neighbouring villages which shared a common water source and whether agriculture was the most important source of cash income for the village. These factors were also the most important variables in explaining the difference in risk when comparing villages with zero or one outbreak with those having four or more. We concluded that the greatest impact on reducing spread of FMD among villages would be obtained through the development of strategies to reduce the likelihood of introduction through livestock purchases and for villagers to take greater care when livestock are grazed with those from neighbouring villages and when sharing common water supplies.

Production of Blank Water for the Analysis of Volatile Organic Compounds in Human Blood at the Low Parts-Per-Trillion Level

Blank water with low levels of volatile organic compounds (VOCs) is of critical importance in many analytical procedures. Because of the increased use of more sophisticated instrumentation, the detection limits for these compounds have dropped dramatically. Consequently, techniques in use in the analytical laboratory to generate blank water may now prove inadequate. The need for blank water with low levels of VOCs was recently underscored by the development of an analytical procedure to analyze 32 VOCs in whole blood; this procedure has detection limits in the tens of parts-per-trillion level for most VOCs. Common sources of blank water in the laboratory such as deionized, cartridge-filtered, and HPLC-grade bottled water are analyzed. These sources contained high concentrations of some VOCs that would interfere with low parts-per-trillion analyses. Well water and bottled water used for human consumption are analyzed, but both prove inadequate for the analysis of VOCs at parts-per-trillion levels. A combination of distillation and purging with helium produced blank water with VOC levels of less than 10 parts-per-trillion for most of the 16 VOCs studied.

Massive ice of the Tuktoyaktuk area, western Arctic coast, Canada

The extensive coastal exposure of massive underground ice at Peninsula Point, southwest of Tuktoyaktuk, Northwest Territories, is believed to be intrasedimental ice. The ice grew beneath a frozen diamicton during the downward aggradation of permafrost. The water source was probably glacier meltwater, with low negative δ18O values, that flowed, under a substantial pressure, through permeable unfrozen sands. Evidence for a high water pressure is shown by ice dikes, which extend upward from the massive ice into the superincumbent diamicton. The diamicton was frozen when the dike water was injected, as proven by the chill contacts and petrofabrics. The diamicton – massive ice contact is a conformable contact with features characteristic of downward freezing. The continuity of δ18O and δD profiles from the top of the massive ice downward to a depth of 10 m into the underlying frozen sand demonstrates a common water source for the massive ice and interstitial ice in the underlying sand. A similar continuity of δ18O profiles has been determined from three drill holes at another site 15 km northeast of Tuktoyaktuk, Northwest Territories. The ages of both the diamicton and massive ice at the Peninsula Point site are uncertain, because of unexplained differences in published radiocarbon dates.

Concentration and form of asbestos fibers in tap drinking water contaminated from a water supply pipe with asbestos-cement

The identification and concentration of asbestos fibers in tap drinking water supplied in a central area of Akita Prefecture, Japan, were determined by phase-contrast microscopy and a scanning electron microscope equipped with an energy-dispersive X-ray microanalyzer. The following results were obtained. 1. Asbestos fibers were found in the tap water from two areas in which an asbestos-cement pipe was used for public water supply. The concentrations of asbestos fibers in the tap water were 2.7 x 10(4) to 27.0 x 10(4) fibers per liter of water in area A and 10.0 x 10(4) to 21.0 x 10(4) in area B. On the other hand, no asbestos fiber contamination was observed in tap water of area C, which shared a common water source with area A. A vinyl chloride pipe was used over the entire length of the water supply in route C. 2. Crocidolite was the predominant type of asbestos fiber detected in the tap water. Chrysotile and a mixture of chrysotile and amosite were also observed. 3. Almost all asbestos fibers detected in the tap water possessed the form of thick or sheaved fibers with lengths ranging from ca. 5 to 10 microns. Their shapes were very different from those of asbestos fibers found in the atmosphere. The typical form of the latter is short (ca. 1 micron in length) and needle-like. 4. It was suggested that the contamination of asbestos fibers in the tap water was caused by erosion and peeling off of the inner wall of the asbestos-cement pipe used as a conduit. In order to evaluate the safety of drinking water in Japan, an extensive survey on asbestos-fiber contamination in tap water is necessary.

Phytoplankton seed populations of the Cape Peninsula upwelling plume, with particular reference to resting spores of Chaetoceros (bacillariophyceae) and their role in seeding upwelling waters

Phytoplankton seed populations of newly upwelled water collected off the Cape Peninsula in the southern Benguela upwelling system were examined. The similar composition of the phytoplankton along the entire base of the plume implies a common source of water during each individual upwelling event. Greater variability in the composition and abundance of phytoplankton of different upwelling events was attributed to varying offshore phytoplankton developmental processes, the success of the seeding strategies of various species and variation in circulation patterns. Such variability was found to be instrumental in determining the species composition and the time required for bloom development. The prevalence of intact diatom resting spores, especially of the genus Chaetoceros, in newly upwelled waters demonstrated the ability of spores to utilize the mixing and current patterns in order to seed upwelling systems. Higher sinking rates would appear to be the key advantage to spore formation, rapidly removing the population from an inhospitable environment following nutrient depletion, thus preventing offshore advection and maintaining the population close to the centre of upwelling. The germination of diatom resting spores following incubation of newly upwelled water provided convincing evidence of the initiation of diatom blooms by resting spores in upwelling systems. These resting stages are therefore of selective advantage in seeding upwelling systems, increasing the chances of a species being represented when conditions are favourable for growth. Thus spore-forming diatom species have been found to be among the most abundant and persistent phytoplankton species in the southern Benguela.

Persistence of Avian Influenza Viruses in Water

Persistence of five avian influenza viruses (AIVs) derived from four waterfowl species in Louisiana and representing five hemagglutinin and neuraminidase subtypes was determined in distilled water at 17 C and 28 C. Infectivity was determined over 60 days by microtiter endpoint titration. One AIV was tested over 91 days at 4 C. Linear regression models for these viruses predicted that an initial concentration of 1 x 10(6) TCID50/ml water could remain infective for up to 207 days at 17 C and up to 102 days at 28 C. Significant differences in slopes for AIV persistence models were detected between treatment temperatures and among viruses. Results suggest that these viruses are adapted to transmission on waterfowl wintering habitats. Results also suggest a potential risk associated with waterfowl and domestic poultry sharing a common water source.

Contaminated produce--a common source for two outbreaks of Shigella gastroenteritis.

Simultaneous outbreaks of Shigella sonnei gastroenteritis occurred in October 1983 at two Texas university campuses 60 miles (96 km) apart. There were no common food handlers, recreational activities, water sources or swimming areas to explain the introduction of Shigella at both campuses. However, tossed salads were found to be associated with illness at both campuses. The investigation disclosed that both schools had received produce shipments from the same company during the week preceding these outbreaks. Shigella isolates from cases at both universities, sent to the Centers for Disease Control for plasmid analysis and colicin typing, were found to be identical. The same organism was evidently not a frequent cause of shigellosis within a 160-mile (256 km) radius of these universities since only 19% of control isolates chosen from this area were identical to the type which caused these outbreaks. This is the first report of two related outbreaks of shigellosis that were caused by a contaminated food source and not by a food handler. Simultaneous foodborne outbreaks of shigellosis should trigger a search for potential contamination at every step of food handling from farm to kitchen.

Adsorption of select phenol derivatives by dolomite

Laboratory experiments were performed to investigate the behaviour of six phenols: 4-chloro-m-cresol, 2,4-dimethylphenol, 2,4-dinitrophenol, 4-nitrophenol, pentachlorophenol, and 2,4,6-trichlorophenol, in dolomite aquifers. The phenols are toxic, persistent in aquatic environments, and used widely in the chemical and manufacturing industry. Dolomite aquifers are common sources of water in many parts of the country. The experimental results are that, with the exception of the chlorinated phenols, little, if any, of the phenols adsorb onto dolomite at temperatures of 5° and 22°C and at concentrations from 0·1 to 10 mg litre −1. Pentachlorophenol adsorbs most strongly, with as much as 22% adsorbing from groundwater onto dolomite. No processes of phenol degradation were detected in the experiments, with some experiments lasting 21 days. Thus, phenols dispersed in an area where they can leach and contaminate dolomite groundwater aquifers would pose a threat to human health and the environment. In contrast to dolomite, chemical sorbents strongly adsorb the phenols and could be used for groundwater cleanup.

The comparative study of patterns of Guinea worm prevalence as a guide to control strategies

Guinea worm, a parasite found in unprotected drinking water sources, causes considerable morbidity and loss of agricultural production among rural people in India and West Africa. A comparative study of village level prevalence data in the two regions reveals marked contrasts in the level and characteristics of prevalence which are useful guidelines in planning control strategies where little is known about local guinea worm epidemioloy. Prevalence rates of up to 75–80% of the total population of a settlement have been found in West Africa, far higher than those in India. The higher figure indicates that all members of a community are exposed to a common infected drinking water source. Here the infection affects all sections of the population who do not treat their water at the household level. In India levels of prevalence for males are far higher than for females, whereas in West Africa the difference in infection rates between the sexes is less marked. In India many men are infected when they are away from the village, attending festivals or farming, and exposed to untreated water sources; women and children travel less and use domestic water sources which are more likely to be treated in some way. Differences in prevalence characteristics according to age, sex or social/economic grouping should be taken into account when planning national and local control campaigns. For example, in Nigeria where women are as likely to suffer from the infection as men, women are the main water collectors and contaminators, and are responsible for domestic water treatment; thus they should be fully involved in control campaigns. Where village level rates are high, community co-operation will be effective as all residents recognize the severity of the guinea worm problem, and a dramatic fall in prevalence rates is possible. Although the complete eradication of the disease in West Africa will be complex because of its widespread distribution and the many sources of infection, the prospects for the eradication of guinea worm are good.

Removal of Organic Matter in Water Treatment

The performance of several types of water treatment plants in removing various molecular weight (MW) fractions of naturally occurring aquatic organic matter and humic substances is described. An assessment was made of the performance of direct filtration, conventional treatment, and softening in removing trihalomethane (THM) precursors from a diverse array of water sources. In addition, a comparison was made between conventional treatment and direct filtration in removing THM precursors from a common water source, the Colorado River. As a general rule, THM reactivity (μg THM/mg C) increased with MW although the <10,000MW range was found to be the most consistently reactive fraction of aquatic organic matter. All of the various treatments preferentially removed the most reactive fraction of precursor present in each molecular weight range. None of the various treatments proved to be very effective in removing precursor material below a MW of <500. The ability to remove THM precursors appears to be related ...

Four Leagues of Pecos: A Legal History of the Pecos Grant, 1800-1933

Water law, water politics, and especially water shenanigans are at the centre of this book about New Mexico and Texas dividing the Pecos River. On one level the story is about a twenty-year court case, Texas vs New Mexico, a monstrous law suit between two states sharing a common water source, a state boundary, and a long history of mutual enmity. On another level, this story is as big and far-reaching as the high plains drained by the Pecos: it is part memoir, part biography, and part environmental history, part the history of hydrology, and part a contribution to the annals of litigation in the great tradition of Anthony Lewis and Jonathan Harr.

Water production models for comet Bradfield /1979 X/

Whipple (1950, 1951) has proposed that water might be the dominant volatile constituent of the cometary nucleus. The considered investigation is concerned with the clues which observations of the cometary coma provide regarding the parents of the dominant observed coma species. In the early part of 1980, comet Bradfield (1979 X) was observed with the aid of the International Ultraviolet Explorer (IUE). These measurements are the first which provide a basis for a comprehensive study of all three water dissociation products, H, O, and OH, simultaneously. The IUE observations of comet Bradfield are compared with the predictions derived from an H2O model. The obtained results indicate that the observed brightnesses of H, O, and OH are certainly consistent with a common water source for all three species.

Oxygen and hydrogen isotope studies on minerals from alpine fissures and their gneissic host rocks, Western Tauern Window (Austria)

Fourteen cogenetic quartz-biotite pairs from gneissic wall rocks, and 22 quartz, 16 calcite, and 8 biotite samples and 1 sample of albite from fissure-filling veins in the Western Tauern Window were analyzed for their oxygen isotope composition. The δ18O values show the following ranges: (a) quartz, +6.0 in fissure in amphibolite to +10.3 in fissures in granite gneisses; (b) biotite, +2.5 to +6.7; and (c) calcite, +7.0 to +8.9. The δ18O value of albite is +7.1. Only a small variation in the hydrogen isotope composition of biotite was detected. δD values of 7 biotites from gneisses and fissure fillings varied from −54 to −59. There is no significant difference in the hydrogen isotope composition of fissure biotite and biotite from the host rock. This indicates that a common water source of probably deep-seated origin existed, with no detectable contribution from isotopically light meteoric water.

Contaminated roof-collected rainwater as a possible cause of an outbreak of salmonellosis.

Roof-collected rainwater is a common water source in subtropical regions and has not been associated with human illness. In Trinidad, the West Indies, a church group, attending a rural camp, developed gastrointestinal illness, caused by Salmonella arechevalata. This rare serotype was isolated from stool specimens of campers, foods eaten at the camp, and a water tap, which was supplied by a storage tank of roof-collected rainwater. The surface of the roof, used as water catchment, was covered with bird faeces. It is postulated that rainwater, falling on the roof, washed off animal excrement which contained S. arechevalata and led to the outbreak of salmonellosis through camper ingestion of contaminated food and water.

Sugar Cane Irrigation: A Case Study in Capital Budgeting

A study of irrigation, economics was conducted in 1963 on a 10,000 acre sugar plantation in Hawaii and repeated in 1964 on three additional plantations covering 34,000 acres. The objective of the study was to recommend, on an agronomic and economic basis, a program for investing large amounts of capital in newly developed automatic and semi-automatic irrigation systems. Although basically a problem in capital budgeting, a number of complicating factors precluded the straightforward application of traditional investment analysis techniques. The more important of these factors were: 1. Many Alternatives. The wide range of physical conditions found on each plantation ruled out the selection of a single “best” irrigation system. As a result, a number of systems had to be evaluated for each of several hundred cane fields. 2. Combinatorial Aspects. Investments in individual cane fields were interdependent since groups of fields shared common water sources; thus, combinations of investments had to be analyzed, increasing the number of investment alternatives astronomically. 3. Opportunity Value of Scarce Resources. New irrigation systems offered substantial water savings. However, the value of these savings arises from the “opportunity” value of water in alternative uses. Alternative uses, in turn, depend on how much water is saved. Thus, no value for potential savings on the plantation could be established until the investment analysis was run, first for individual alternatives and then for combinations of alternatives. 4. Complicated Timing. Because of crop planting schedules, new systems would be installed on small increments of acreage over a period of 8 to 10 years. Thus, “nonconventional” investments (outlays interspersed with benefits such that the stream of cash flows had multiple sign changes) occurred in multiple time periods; furthermore, because of crop harvesting schedules, returns from these investments also were distributed over multiple time periods with varying amounts of delay between investments and returns. The approach used to solve this problem is described in the paper.

Growth and Reproduction of Leptomonas oncopelti in the Milkweed Bug, Oncopeltus fasciatus

SYNOPSIS. A laboratory colony of Oncopeltus fasciatus was found to be infected with Leptomonas oncopelti. Inasmuch as the parasite is transmitted from parent to offspring an opportunity presented itself to study the biology and transmission of this parasite under controlled laboratory conditions. An apparatus for observing individual bugs was designed and the presence or absence of flagellates in the feces determined. Flagellates were not shed until the bugs became adults after which they appeared in every defecation. Dissection of infected bugs revealed that flagellates were not present in the rectum until adulthood. Further studies indicated that in the midgut of the insect there is a departure from binary fission to budding. The nucleus divides and one of the newly formed nuclei migrates toward a newly formed kinetoplast. Rarely there is still another kinetoplast/nucleus division. In the event the new axoneme grows within the cytoplasmic sheath of the parent flagellum, smaller organisms produced by unequal cytokinesis remain attached. If the axoneme grows free, the smaller daughter organisms become free‐swimming. Passage into the rectum of the adult bugs causes a rounding up of all parasites although the leishmaniform organisms continue to divide. It is presumed that infection of clean bugs is accomplished by the ingestion of leishmaniform organisms through a common water source. The reason for the presence of flagellates in the rectum of the adult but not in the nymphal insect and the mechanism responsible for the change from binary to unequal fission are not known.

Plugging Off Water in Fractured Formations

Abstract A field remedial procedure utilizing a kerosene-cement slurry as a water plug-off agent in fractured formations was evaluated both in the laboratory and in the field. This procedure has proved to be capable of effectively shutting off water without causing permanent impairment of the oil production. Success was attributed to the fact that an immobile cement slurry, when placed in a water-producing strata, will set and form an impermeable barrier; whereas when placed in an oil-producing section the cement will retain a relatively high permeability and may be removed by acidizing. Introduction One of the most perplexing problems facing the oil industry is the selective exclusion of water production from oil or gas-producing wells. This problem has been studied by many investigators in an attempt to develop a material that is not only capable of reducing water production but is also capable of being selective in that it will not impair oil production in either fractured or intergranular type reservoirs. A study of these two types of formations indicated that two distinct types of materials for controlling water production might be required - a completely liquid plugging agent for intergranular formations and a semi-liquid or slurry type plugging agent for fractured formations. This paper is limited to the control of water production from fractured formations. A common source of water in the vicinity of oil bearing rock reservoirs is water which previously has entered and, because of its higher density, generally lies near the bottom of the formation. When the deepest point of penetration of a well into such an oil and water-bearing formation is above the level of the water, and the dynamical gradients due to the flow of oil overbalance the difference in densities between oil and water, water production becomes a problem. Then the water level rises in the shape of a cone and is produced from the lower depths.