Sign posted along trail
There is (lots) more information on the Arlington County web site.
Construction at Four Mile Run will begin on Sept. 20, lasting through the Fall season. There is a detour associated with the project.The signs may have appeared last Friday I guess but there were no signs Thursday last week; supposedly construction starts tomorrow? But maybe not the detour.
Here is a PDF of the map I have a photo of, above.
Not surprisingly I am not crazy about the detour. I get the need for the project I just don't like the route of the detour, and that there is no sensible alternative. This detour is two miles into a 9.5 mile commute, but there is no alternative route via trails. The trail network is great except it is not very dense as a network. Phooey.
It is amusing (or something) to see the tacit admission that the present trails are not very good when it says, "As part of the construction, the Arlington trail will be completely rebuilt to current standards, including a new sub-base and asphalt surface." Of course they are just referring to the less than half mile of trail to be upgraded with this project; the remainder of this trail (and others) will remain sub-standard.