I do not know if it would speed things up significantly, but this contribution would definitely make things easier for municipalities. In fact, I believe that this would actually help the process because municipalities would have to pay less out of their own coffers.
If the federal government covers a larger portion of infrastructure expenditures, municipalities will certainly be more likely to fund a smaller portion of the projects. Therefore, this should generate more projects and probably do so more quickly. There would not be much of a difference in regions experiencing labour shortages, but it would really make things easier for municipalities if their contribution was reduced.