The Geomatics and Landscape Ecology Research Laboratory at Carleton University has also done a conservation study on amphibians to determine the effect of road and land use around local ponds and the effect they have on frog and toad populations.
You can read more about the conclusions of their study and the recommendations in the following online brochure.
A short summary is: Terrestrial habitat of up to 2 kms around breeding sites (ponds, wetlands and wet forests) needs to be conserved along with networks between breeding sites (corridors). Reduced traffic along roads within these boundaries is key. Both forest and open space are important to have a diverse frog and toad population in urban/suburban areas.