The mapping of the small hydropower (SHP) resource over a given territory is indispensable to identify suitable sites for the development of SHP renewable energy projects. In this study, a straightforward method to map the SUP potential over a large territory is presented. The methodology uses a synthetic hydro network (SHN) created from digital elevation models (DEM) to ensure precise hydro head estimations. From the SHN, hydro heads are calculated by subtracting the minimum from the maximum elevation of synthetic stream segments. Subsequently, stream segments with low hydro heads over a specified maximum distance are removed. Finally, the method uses regional regression models to estimate the annual baseflow for all drainage areas in the study area. The technical SHP potential can then be estimated as a function of the hydro head and maximum penstock length. An application of the method is made to the province of New Brunswick, Canada, where SHP maps have been developed to promote the development of the SUP energy sector in the province. In terms of the SHP opportunity, it is shown that the province of New Brunswick (71,450 km(2)) has a good SHP resource. Using a representative hydro head (10 m) and penstock length (3000 m) for the region, 696 potential sites have been identified over the territory. Results show that the technical SHP potential for New Brunswick is 368 MW for the conventional hydroelectric reservoir SUP configuration, while for the run-of-river SUP configuration, the technical SHP potential is 58 MW. (C) 2011 Elsevier Ltd. All rights reserved.