This article focuses on how urban street design will need to respond to changes in mobility, new types of vehicles using the roads, and currently unmet functional needs. Infrastructure typically lasts a generation, so...This article focuses on how urban street design will need to respond to changes in mobility, new types of vehicles using the roads, and currently unmet functional needs. Infrastructure typically lasts a generation, so it must be built anticipating future needs. However, despite widespread agreement that the types of vehicles using roadways and patterns of usage are likely to change, design standards rooted in the past continue to guide the process of creating streets in China. The article begins with an understanding of current deficiencies of streets, and a prognosis of how the mobility system is likely to evolve. Based on this, it suggests new patterns for streets of the future.展开更多
Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety...Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl<sup>-</sup>), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.展开更多
文摘This article focuses on how urban street design will need to respond to changes in mobility, new types of vehicles using the roads, and currently unmet functional needs. Infrastructure typically lasts a generation, so it must be built anticipating future needs. However, despite widespread agreement that the types of vehicles using roadways and patterns of usage are likely to change, design standards rooted in the past continue to guide the process of creating streets in China. The article begins with an understanding of current deficiencies of streets, and a prognosis of how the mobility system is likely to evolve. Based on this, it suggests new patterns for streets of the future.
文摘Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl<sup>-</sup>), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.
