Modelling of methoprene concentration at storm sewer outfall

The objective of this report is to compare the predicted concentration of methoprene, a larvicide used in the City of Toronto to control the widespread of West Nile Virus by suppressing mosquito growth, at storm sewer outfall during a typical year rainfalls (1980 rainfalls) with the Interim Provincial Water Quality Objectives (IPWQO). The methoprene that is under investigation in this report is in form of ingot. Extending from an existing spreadsheet-based model that simulates the methoprene concentration within two monitored catch basins in the Newtonbrook sewershed of North York, methoprene concentration at the sewer outfall during the 1980 rainfalls is predicted by linear projection upon calibration of the model with the methoprene mass at the outfall measured in year 2005. Results show that predicted methoprene concentration at outfall exceeds the IPWQO in six days out of the one-hundred-day period. It is recommended that to better mimic the actual situation, traveling time effect and sensitivity analysis on catch basin sump volume be included in future study.

Modelling of methoprene concentration at storm sewer outfall

The objective of this report is to compare the predicted concentration of methoprene, a larvicide used in the City of Toronto to control the widespread of West Nile Virus by suppressing mosquito growth, at storm sewer outfall during a typical year rainfalls (1980 rainfalls) with the Interim Provincial Water Quality Objectives (IPWQO). The methoprene that is under investigation in this report is in form of ingot. Extending from an existing spreadsheet-based model that simulates the methoprene concentration within two monitored catch basins in the Newtonbrook sewershed of North York, methoprene concentration at the sewer outfall during the 1980 rainfalls is predicted by linear projection upon calibration of the model with the methoprene mass at the outfall measured in year 2005. Results show that predicted methoprene concentration at outfall exceeds the IPWQO in six days out of the one-hundred-day period. It is recommended that to better mimic the actual situation, traveling time effect and sensitivity analysis on catch basin sump volume be included in future study.

Problems of the Goal-setting in Public Planning of Water/protective Measures in River Basins

The paper presents detailed analysis of the norm/methodical and guiding documents currently in force that support choice of goals and priorities in public planning water/protective activities. The authors have assessed advantages and disadvantages of the «Regulations on development, setting and revision of the environment quality norms for chemical and physical indicators of the environment status», as well as relevant regulation acts in terms of setting water quality norms for surface water bodies with taking into account territorial differentiation of the water quality formation conditions. The authors presented some proposals for further development of the system of water quality normalization. In particular, we recommended: to abandon accounting of the water use types in setting norms of the surface water quality as a component of environment; to take into account the natural background at the expense of the state budget; and to use widely tested and approved mechanisms of water quality objectives as a methodical base for water quality normalizing. The scheme of coordinating the procedure of the comprehensive ecological permissions’ issue with the water quality objectives.

Justifying exemptions through policy appraisal: ecological ambitions and water policy in France and the United Kingdom

The Water Framework Directive aims to achieve ‘good status’ for all water bodies in the European Union. However, exemption clauses enable member states to delay protective measures and to lower water quality objectives. The ambiguity of exemption clauses has led to a plurality of approaches across the continent. They differ as to their political objectives, i.e., the overall ambition displayed in implementing the Directive, and to their methodological choices, i.e., the analytical tools used to justify exemptions. This article argues that those political and methodological dimensions influence each other. Relying on a framework of analysis that integrates key recommendations from the literature, we explore the usage and justification of exemptions in two countries, the United Kingdom and France. Our analysis suggests that analytical methods were often decided so as to reflect the ecological ambitions of a country, and some methodological choices seem to have had unintended consequences for water quality objectives. We conclude that economic methods should be adapted so that they take into account, rather than ignore, the political ambitions of a country in the field of water.