Flight Crew Commercial; Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 20; Flight Crew Total 1200; Flight Crew Type 600
Communication Breakdown
ATC Issue All Types; Conflict NMAC
General None Reported / Taken
Human Factors
I called LVK Tower from Altamont pass for landing. At about the same time a C152 called for landing from Brushy peak. This landmark is about 3 nm North of Altamont pass. The Tower controller instructed me to report 4 miles out for 25R. I believe the 152 was instructed to report a 2 mile left base for 25R. As I reached the 4nm distance; the 152 called 2 mile left base. The controller instructed him to change to 25L and cleared him to land. I called in immediately after that and I was cleared to land on 25R. This resulted in the 152 crossing my flight path. In fact he crossed directly underneath me about 50 feet lower than me.  If I had descended a bit more quickly; we would have collided. I never saw the 152 and I don't think the Tower controller ever told me where he was. I think the 152 might have reported me in sight; I don't remember clearly. He might have been a student pilot.Anyway; because of the near miss and the confusion that almost led to a fatal accident; I believe a careful review of this incident is in order; including review of the recorded audio and radar tracks.
Pilot of C-172 experienced a NMAC with C-152 while on visual approach to a parallel runway.