Impacts of urbanisation on hydrological processes are different for snowmelt and rainfall events. Furthermore, snowmelt and runoff generation differ between rural and urban areas. Within an urban area, melt intensities are increased at some sites; hence, the volume of water early in thaw can be greater than in rural areas. However, shading can reduce melt in other areas so that the melt period is extended. Many surfaces are at least seasonally impervious and generate overland flow - there is an apparent increase in the area contributing to quickflow as normally permeable surfaces become saturated or frozen or both. Water infiltrating permeable soil causes saturation and groundwater recharge so that water can seep into sewers. Regardless of whether water enters via inlets or sewer infiltration, drainage networks ensure swift delivery of melt water to outlets.
Snowmelt induced runoff reaching the Uddebo Waste Water Treatment Plant in Luleå, Sweden, is investigated and a model of urban snowmelt and meltwater routing is proposed. The role of surface type (permeable and impervious) and snow cover characteristics (snow-free, undisturbed, compacted and piled) upon model output is studied. Results are encouraging and provide a good platform for further research.
