So a central part of the Greenbelt is closed until Fall 2016 because of construction on the Broadway Bridge. This will impact many of our Greenbelt runs. There is a detour around the construction which is mapped out here. This extra section adds about 0.5 miles to any Greenbelt loop (unless you were planning to go across the Broadway Bridge, of course).
On the north side of the river (through Julia Davis park), take the last driveway out of the park to Myrtle St. Stay on Myrtle past the Ram as it becomes Park and take the first road on the right, Ferguson St. This will lead you back to the Greenbelt.
Going back, get off the Greenbelt just after the small wooden foot bridge and follow Leadville Ave south for one block. Turn right on Belmont St then right on Longmont Ave. This takes you behind Chili’s and brings you to Broadway just outside the construction area. Cross Broadway and stay on Cesar Chavez Ln until you can get back on the Greenbelt.
The whole detour should be well signposted but if you have any questions about where to go, grab one of the regular runners at the next Greenbelt run and they’ll make sure you don’t get lost.
One thing to note about the map is that Google doesn’t seem to know about the stairs up to the W Parkcenter Bridge which adds a larger loop than you need to run.