The future development, possibly to be called Anthem Cathedral Square, at J Street & 11th Street is currently a hole in the ground. The old buildings have been razed, and debris hauled away, but new construction has not started, so it will be some while before J Street on the north side of the site (south side of the street) returns to normal.
A channelized bypass should be created to carry the sidewalk for walkers and the bike lane for bicyclists past this construction site, between 10th St and 11th St, by removing a general purpose travel lane from J Street. The aerial below (before removal of the buildings) shows a sidewalk, a parking lane, a bicycle lane, three general purpose travel lanes, and a parking lane. The channelized bypass would include a shared pathway for walkers and bicyclists, in place of the right hand general purpose lane. The bypass can be created with use of orange construction barrier, as was done on 9th Street. This bypass would remain in place until construction is complete.

While the razing and cleanup was going on, there was decent signing, but it has disappeared or been moved to the side. The first set is the former signage at J St & 1oth St, and then today without an signage. There should be a sign here, the MUTCD R9-11; a barrier is not appropriate at this location since the closure is ahead and there are businesses open.
At the sidewalk closure point, there is an acceptable barrier but no signage. At this point, it looks like there could be a bypass, but it is fenced off. The appropriate sign here is MUTCD R9-9.
At J St & 11th St southeast corner, there was a barrier and signage, but the barrier has been moved to the side and the signage is gone. There should be a barrier and sign here to indicate that the crosswalk is closed. The third photo is an example of a correct barrier and signage.
At J St & 11th St northwest corner, there should be a barrier and signing to indicate the crosswalk is closed, but neither is present.

This construction zone failure is one among many in Sacramento. The city is not creating traffic control plans that accommodate walkers and bicyclists, and the construction companies are not appropriately placing signs and barriers. This is a violation of the ADA (Americans with Disabilities Act). Responsibility for encroachment permits (when the construction project goes into the public right of way, which includes sidewalks), and traffic control plans to mitigate the situation, rests with the City of Sacramento Department of Public Works.
I have created a new category, construction zone, which will make is easier to find other posts on the construction zone topic. Photos of many construction zone locations are on Flicker in Sac construction-zone album.