Parking meters going in on 4th Ave?

Just this past week, posts have gone in for parking meters along 4th ave on at least the block between 45th and 48th street, although I think it may extend in both directions who knows how many blocks. Street signs changed to "one hour parking."

This is terrible! Residential parking is hard enough in SP what with all the illegal "driveways", without now the spots on 4th ave becoming unavailable. And it's not like 4th ave is a shopping district where people are running in and out of their cars.

And why parking meters, not muni meter thingy?

Does anyone know anything about this? It seems kind of sudden.