Cheetah; Tiger; Traveler AA5 Series
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 7
Workload; Distraction; Situational Awareness; Confusion
Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
Human Factors; Procedure; Environment - Non Weather Related; Aircraft
Aircraft X was instructed to taxi via D taxiway to Rwy 9L.  He took a parallel taxiway C instead.  Aircraft Y had been instructed to taxi via G;C; and H to the ramp.  When Aircraft Y  got to C taxiway he informed he was holding short C.  I looked up and saw Aircraft X on taxiway C near G.  By that time it was too late to say anything and he sidestepped to D and continued his taxi.  I was so busy writing up strips on other aircraft; following our new procedures; that I was not able to turn around and see the conflict.  This is a problem having Ground Control combined up with FD/CD with our new procedures.  It doesn't work well. Too much time is spent writing and looking down instead of looking up and watching for aircraft turning on the wrong taxiways or doing other unsafe procedures.  We either need to change the procedures in order to accommodate the times we combine up FD/CD with Ground Control or have more controllers working the shifts so that we have adequate coverage to safely work the traffic and use the new procedures that were put in place.  I think these new procedures are unsafe when we work the positions combined.  I saw another controller later  today having trouble working the positions combined.
TMB Ground Controller reports of issuing taxi instructions to two aircraft and then having them at the same intersection because one went the wrong way.  Controller was working Flight Data/Clearance at the same time and doing those functions.