IMPROVING FLOW DISTRIBUTION IN SMALL-SCALE WATER-SUPPLY SYSTEMS THROUGH THE USE OF FLOW-REDUCING DISCS AND METHODS FOR ANALYZING THE EFFECTIVENESS OF SOLAR POWERED PUMPING FOR A DRINKING WATER SUPPLY IN RURAL PANAMA

As continued global funding and coordination are allocated toward the improvement of access to safe sources of drinking water, alternative solutions may be necessary to expand implementation to remote communities. This report evaluates two technologies used in a small water distribution system in a mountainous region of Panama; solar powered pumping and flow-reducing discs. The two parts of the system function independently, but were both chosen for their ability to mitigate unique issues in the community. The design program NeatWork and flow-reducing discs were evaluated because they are tools taught to Peace Corps Volunteers in Panama. Even when ample water is available, mountainous terrains affect the pressure available throughout a water distribution system. Since the static head in the system only varies with the height of water in the tank, frictional losses from pipes and fittings must be exploited to balance out the inequalities caused by the uneven terrain. Reducing the maximum allowable flow to connections through the installation of flow-reducing discs can help to retain enough residual pressure in the main distribution lines to provide reliable service to all connections. NeatWork was calibrated to measured flow rates by changing the orifice coefficient (θ), resulting in a value of 0.68, which is 10-15% higher than typical values for manufactured flow-reducing discs. NeatWork was used to model various system configurations to determine if a single-sized flow-reducing disc could provide equitable flow rates throughout an entire system. There is a strong correlation between the optimum single-sized flow- reducing disc and the average elevation change throughout a water distribution system; the larger the elevation change across the system, the smaller the recommended uniform orifice size. Renewable energy can jump the infrastructure gap and provide basic services at a fraction of the cost and time required to install transmission lines. Methods for the assessment of solar powered pumping systems as a means for rural water supply are presented and assessed. It was determined that manufacturer provided product specifications can be used to appropriately design a solar pumping system, but care must be taken to ensure that sufficient water can be provided to the system despite variations in solar intensity.

Fog-water collection for community use

Fog is a potential source of water that could be exploited using the innovative technology of fog collection. Naturally, the potential of fog has proven its significance in cloud forests that are thriving from fog interception. Historically, the remains of artificial structures in different countries prove that fog has been collected as an alternative and/or supplementary water source. In the beginning of the 19th century, fog collection was investigated as a potential natural resource. After the mid-1980s, following success in Chile, fog-water collection commenced in a number of developing countries. Most of these countries are located in arid and semi-arid regions with topographic and climatic conditions that favour fog-water collection. This paper reviews the technology of fog collection with initial background information on natural fog collection and its historical development. It reviews the climatic and topographic features that dictate fog formation (mainly advection and orographic) and the innovative technology to collect it, focusing on the amount collected, the quality of fog water, and the impact of the technology on the livelihoods of beneficiary communities. By and large, the technology described is simple, cost-effective, and energy-free. However, fog-water collection has disadvantages in that it is seasonal, localised, and the technology needs continual maintenance. Based on the experience in several countries, the sustainability of the technology could be guaranteed if technical, economic, social, and management factors are addressed during its planning and implementation.

Use of Otolith Strontium:Calcium Ratios for Hindcasting Larval Cod Gadus Morhua Distributions Relative to Water Masses on Georges Bank

The concentration ratios of strontium to calcium in laboratory-reared larval cod otoliths are shown to be related to the water temperature (T) at the time of otolith precipitation. This relationship is curvilinear, and is best described by a simple exponential equation of the form (Sr/Ca x 1000 = a exp(-T/b). We show that when Sr/Ca elemental analyses are related to the daily growth increments in the larval otoliths, relative temperature histories of individual field-caught larvae can be reconstructed from the egg stage to the time of capture. We present preliminary examples of how such reconstructed temperature histories of Atlantic cod Gadus morhua larvae, collected on Georges Bank during April and May 1993, may be interpreted in relation to the broad-scale larval distributions and the hydrography of the Bank.

Concentration of trace elements in samples of sea water determined by use of two methods of concentrating

A device and a specific procedure for simultaneous concentration of trace ele¬ments from sea water by co-precipitating them in precipitate of magnesium hydroxide obtained by electrolytic alkalization of samples in a two-chamber electrolyzer are described. Analyses of sea water samples for zinc, iron, copper, nickel and lead demonstrate that the method produces a thousand-fold concentration and gives results that agree well with those obtained by extractive concentration using diethyldithiocarbamate and 8-hydroxyquinoline in chloroform. Extracts were analyzed by flame atomic absorption. Correlation coefficients of results obtained with use of these two methods of concentration were 0.76-0.87 for zinc, iron, and copper at confidence levels of 0.05-0.07. Average zinc and iron concentrations determined by the method differed by less than 10%.

The Extended Water Footprint and illegal groundwater use in the Upper Guadiana Basin (Spain)

Tablas de Daimiel National Park is located in the Upper Guadiana Basin and represents one of the largest and most important wetlands in Europe. The long term ecological integrity of this wetland is inherently associated with the maintenance of a shallow groundwater table, namely the Western Mancha aquifer (WMA) or Aquifer 23. The intensive use of groundwater, mainly for irrigation, has led over the last decades to deep socio‐economic changes. Such intensive use has also lowered the water table of Aquifer 23, drastically reducing the flooded area of the wetland and threatening its ecological integrity. A number of plans and measures have been developed and implemented since the declaration of overexploitation of Aquifer 23 in the year 1987. The most recent one is the Special Plan for the Upper Guadiana (SPUG), approved in 2008. This Plan is the main measure to comply with achieving the objective of good quantitative and qualitative status required under the Water Framework Directive (2000). This paper offers a new type of integrated analysis which allows assessing under a common lens the physical, economic and social dimensions of groundwater use in the area. The first objective is to calculate the groundwater footprint of agricultural production in the Upper Guadiana basin and its evolution during 2000‐2008. For this purpose, we have applied the Extended Water Footprint (EWF) methodology ‐a novel approach based on the classical Water Footprint (WF) approach‐ that includes an assessment of the water productivity from an economic and social perspective. Compared to the classical WF, the EWF allows for a more complete overview of the sector, providing new insights for policy decisions (e.g. to define options and possibilities on water re‐allocation in order to achieve both better ecosystem conservation and social equity). The second objective is to use the EWF to compare the existing authorized and non‐authorized or illegal use of water. This allows us to discuss current initiatives by public authorities in relation to the existing frame of water rights

Use of spacecraft data to derive regions on Mars where liquid water would be stable

Combining Viking pressure and temperature data with Mars Orbital Laser Altimeter topography data, we have computed the fraction of the martian year during which pressure and temperature allow for liquid water to be stable on the martian surface. We find that liquid water would be stable within the Hellas and Argyre basin and over the northern lowlands equatorward of about 40°. The location with the maximum period of stable conditions for liquid water is in the southeastern portion of Utopia Planitia, where 34% of the year liquid water would be stable if it were present. Locations of stability appear to correlate with the distribution of valley networks.

Illinois Phosphorus Effluent Limits: Minimizing the Impacts Through the Use of Non-point Controls at the Springbrook Water Reclamation Center in Naperville, Illinois

Phosphorus pollution is a major concern in Illinois. Excessive amounts of phosphorus can be detrimental to water bodies. To help control phosphorus, the Illinois Pollution Control Board has proposed phosphorus limits on wastewater treatment facility discharges. If enacted, these limits will have negative impacts on the Springbrook Water Reclamation Center in Naperville, Illinois. To minimize these impacts, Naperville can utilize various non-point controls recommended in this paper to decrease the amount of phosphorus entering into the DuPage River and the Springbrook Water Reclamation Center. While these controls will not reduce levels low enough to totally satisfy limits on phosphorus discharges, they will significantly reduce the treatment costs Naperville will need to expend to meet them and be more environmentally effective.

Troubled Waters Ahead: An Evaluation of Shoreline Land Use Policies for Water Quality Protection in Renfrew County, Ontario

Increases in the rate and extent of lakeshore development along inland lakes in Ontario are adversely impacting water quality. Despite growing awareness, there is a lack of knowledge about the land use policies and tools in place to protect inland lakes in rural Ontario. This research evaluated official plans for water quality protection policies for inland lakes in the County of Renfrew, Ontario to address this gap. The findings suggest that municipalities implicitly link water quality to land use planning policy and fail to incorporate innovative methods to protect water quality.

Planning methodologies for analysis of land use/water quality relationships /

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