JUST when the traffic situation seemed to be improving in one part of Metro Manila, it would get jammed elsewhere in the metropolis. At one time, flooded streets around the Manila City Hall caused south-bound traffic to back up as far back as España Blvd. in Sampaloc. That appears to have been solved by repairs on drainage channels. Last Monday, traffic was again jammed all around Quiapo and surrounding areas. This time, motorists blamed construction work on Quiapo bridge, where a layer of asphalt was being laid on one lane.