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A methodology and assessment of the thermal balance of an on-stream storm-water pond are documented for a test facility in Kingston, Ontario, Canada. An energy balance model was used to estimate average pond water temperature as a function of thermal energy stored in the pond. Major thermal energy fluxes considered within the pond system included radiant heating and cooling of the pond, evaporation, and thermal energy inflow from the upstream catchment and outflow from the pond. A thermal energy balance was achieved between thermal energy input and output measured over the field season. During dry-weather periods, pond temperature increased as a result of solar heating, and thermal energy input exceeded output. Conversely, during wet-weather periods, pond temperature decreased as a result of limited solar radiation and replacement of warm pond water by cool inflow water from the upstream catchment, and thermal energy output exceeded input. A series of discrete temperature surveys in the pond revealed that the location of the stationary temperature probe, used to measure pond temperature, resulted in an underestimation of the average pond temperature during dry and wet-weather periods. However, this discrepancy was comparable to the difference between measured and modeled values, which further confirmed the model validity.

Presents a methodology for assessing the thermal balance of an on-stream storm-water management pond and its application to a specific facility in Kingston, Ontario. Description of Kingston pond; Verification of the energy balance model; Conditions that led to increased water temperatures in ponds and receiving waters; Conclusions.

Examines influential variables and continuous reactor operation in bioleaching, a bioremediation process for the treatment of urban stormwater sediments contaminated with trace metals. Quantification of metabolic activity by acid production; Effect of temperature on acid production; Operation of pilot-scale bioreactors and efficiency of trace metal solubilization.

Presents a method for evaluating the pollution control performance of an on-stream stormwater pond in Kingston, Ontario in removing selected urban stormwater constituents. Constituent mass balances for both baseflow and event conditions as basis for the assessment; Removal rates for contaminants; Regulation of constituent removal by physical processes.

The article presents a speech by W.E. Watt, ventilating engineer of the city of Chicago, Illinois, delivered at the United States National Education Association Conference on August 16-22, 1915 in Oakland, California. Watt called for the design of school buildings that feature windows supporting natural ventilation. Natural ventilation promotes efficiency and health in students and teachers and saves energy costs.

Two subsurface flow constructed wetlands were tested for pollutant removal performance in conjunction with an on-line stormwater detention pond, in Kingston Township, Ontario. The 4.9 m{sup}2{end} wetland cells were filled with 9 mm limestone gravel, and planted with cattail, common reed and spike rush. Changes in nutrient (total organic carbon, PO{sub}4{end}{sup}3-{end} and NH{sub}4{end}{sup}+{end}), suspended solids and metal (Cu, Pb, Zn) concentrations were used to assess performance. Contaminant removal occurred through a combination of physical, chemical and biological means. As with any biological system, variation in performance of stormwater wetlands can be expected to occur as a result of fluctuations in contaminant loading, contact time and ambient environmental conditions. Storm pond effluent was delivered in continuous flow through the wetlands (during baseflow and event conditions), with a detention time of 1 to 3 days. The wetlands were able to maintain removal rates of up to 39 percent for orthophosphateeven during the more severe conditions of fall dieback. Average removal of suspended solids (46 percent ) and dissolved metals (Cu 50 percent ) remained similar throughout all tests. Organic carbon was reduced by less than 10 percent during these tests. Low nutrient levels in the pond effluent were supplemented by spiking with sources of carbon, nitrogen and phosphorus during pulsed loading conditions. Daily sampling produced a time series, which illustrated the rates of decline in concentration of nutrients. First order kinetic assimilation rates ranged from 1.7 d{sup}-1{end} for NH{sub}4{end}{sup}+{end} to 0.12d{sup} -1{end} for organic carbon, which were noticeably lower when compared with municipal and industrial wastewater treatment rates. Three methods of sizing stormwater wetlands (impervious surface area, volumetric load and kinetic reaction rates) were compared using the same design storm and data from this study. From this comparison it wasse [ABSTRACT FROM AUTHOR]