Managing flood risks has been an integral part of the human survival efforts since historic times. During the last decades, global changes brought on by population growth, climate change, urbanization, migration and land conversion, are altering the Earth water cycle and have increased flood risks. None of these factors alone would be sufficient to explain the observed increase in the flood risk. This paper presents a study that aims to evaluate the causes for flood risk increase and to assess the effectiveness of two techniques for flood risk mitigation. One in at the stream course scale and the other at the home scale. The research was conducted in the catchment of the Yzeron River in western Lyon. The catchment area is 130 km2 and characterized by a rapidly expanding, peri-urban development. To evaluate the specific impact of urban development on the flood regimes we used a diachronic approach, with hydrologic and land-use data from two periods, the seventies and the nineties. A semi-distributed hydrological model was fitted (Radojevic et al., submitted) to and validated with a set of last decade floods and corresponding rainfall data. Keeping the same rainfall data, it was then ran with the seventies land use data. Calculated flood regimes characteristics from observations and simulations were significantly different opening the assumption that the rainfall regime would have also changed between these two decades. Model simulation was also extrapolated to expected land use on 2050. This last simulation revealed a five folds increase of the ten years flood peak. Considering that both land use change and rainfall regimes would significantly modify a flood regime, we compared the efficiency of technical solutions to mitigate land use and rainfall influence on a flood regimes. Three situations were tested based on one dry reservoir, two dry reservoirs and home scale temporary rainfall retention facility. It results that dry reservoir number and location are strategic considerations to avoid concomitancy of floods at a main confluence. The home scale rain water temporary retention would be a very efficient strategy but test including the effect of their distribution at a basin scale is required.