Articles | Volume 370
https://doi.org/10.5194/piahs-370-29-2015
https://doi.org/10.5194/piahs-370-29-2015
11 Jun 2015
 | 11 Jun 2015

Analysing the impact of urban areas patterns on the mean annual flow of 43 urbanized catchments

B. Salavati, L. Oudin, C. Furusho, and P. Ribstein

Abstract. It is often argued that urban areas play a significant role in catchment hydrology, but previous studies reported disparate results of urbanization impacts on stream flow. This might stem either from the difficulty to quantify the historical flow changes attributed to urbanization only (and not climate variability) or from the inability to decipher what type of urban planning is more critical for flows. In this study, we applied a hydrological model on 43 urban catchments in the United States to quantify the flow changes attributable to urbanization. Then, we tried to relate these flow changes to the changes of urban/impervious areas of the catchments. We argue that these spatial changes of urban areas can be more precisely characterized by landscape metrics, which enable analysing the patterns of historical urban growth. Landscape metrics combine the richness (the number) and evenness (the spatial distribution) of patch types represented on the landscape. Urbanization patterns within the framework of patch analysis have been widely studied but, to our knowledge, previous research works had not linked them to catchments hydrological behaviours. Our results showed that the catchments with larger impervious areas and larger mean patch areas are likely to have larger increase of runoff yield.

Download
Short summary
We applied a hydrological model on 43 urban catchments in the United States to quantify the flow changes attributable to urbanization. Then, we tried to relate these flow changes to the changes of urban/impervious areas of the catchments. We argue that these spatial changes of urban areas can be more precisely characterized by landscape metrics. Our results showed that the catchments with larger impervious areas and larger mean patch areas are likely to have larger increase of runoff yield.