Whoever owns the road can close it, whether the owner is private, a municipality, state, or other entity (such as the federal government in the case of federal installations).
I work at a public water and sewer utility. Most of our infrastructure is in public roadways. To repair or replace our infrastructure, we apply for an excavation permit to the owner of the roadway. They grant the permit and apply any necessary preconditions. These might include limits on how long and when the road can be closed*, and what type of traffic control is required (e.g. alternating one-way traffic with police or flaggers, or even a full detour). They also dictate what type of roadway restoration is required after our work is complete.
We then close the road (following the conditions of our permit) to do our work. No court order required.
*In the case of busy roads, this can get very involved, like requiring work to be completed between 9:00 a.m. to 3:00 p.m. to avoid rush hour traffic, or during the overnight hours. In cases like this, we are often required to conduct daily temporary paving to restore the road at the end of each construction day. Sometimes this is not possible, and we have to install Jersey barriers around the excavation, or place steel road plates – but again, the owner of the road has to approve this.
Imagine you own a large urban hunk of land. Imagine it is crisscrossed by minor streets that go only to your property. This means you really do not own one big hunk of land, but rather a number of adjacent plots. You might then want to take over & close these minor streets. You may want to do this to consolidate your many small plots into one big one for a large building project. Another reason would be to reduce the amount of road frontage you own, and so reduce your taxes.
I am glad you are able to use that road again, but I will also say that a year to settle a property dispute is actually pretty good.
About 15 years ago, my BFF and spouse bought a large piece of property out in the middle of nowhere and had a house, horse barn and fencing put in. Due to the fact that it was in the middle of nowhere, they also had to have power lines and an access road put in. They did this trusting that the title search/Realtor/survey folks had correctly identified the easement. 13 years later, someone bought a large piece of property next to them and blocked off their road. After almost 2 years of legal battles, it turned out that the title company hadn’t done their part and my BFF (who was now a widow) didn’t have access to her land. Her lawyer promptly demanded that the title company pay the 10 grand the land owner was demanding for allowing the easement. After almost 3 years, she got to drive on that road again.