Narrative:

I landed runway 28L and taxied clear on taxiway T and transitioned to taxiway D; headed for the gate. The taxiway border lights (blue) that normally outline the 'island' that extends east and west between taxiway K and taxiway D were either not illuminated or were turned down so low as to be invisible in darkness. The taxiway centerline lights that lead into taxiway D from the north were also only partially illuminated; and went dark as the taxiway joined taxiway a and the ramp. As I taxied south on taxiway D and turned slightly right (west) to join the ramp; I realized that I had actually entered the eastern end of the 'island.' this area is entirely paved. Most of the area is painted green; except for the area that I taxied on; which is unpainted concrete that appears exactly as the txwys. An additional visual clue that sfo has running through the 'islands' that are paved is a line of vertical plastic 'pickets.' this unlighted unpainted area was also devoid of 'pickets' on the eastern end (which I taxied across). We smoothly traversed the eastern end of the 'island.' there were no obstacles or foreign objects in this area that might have presented a hazard to the aircraft; and a thorough post flight inspection was completed (by me). Under similar night conditions that might include a restriction to visibility (rain on the pavement); I'm sure that I wouldn't have even realized that I had traversed the 'island.'

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Original NASA ASRS Text

Title: B737-300 CAPT RPTS TXWY/RAMP MARKINGS AND LIGHTING OF HARD SURFACE 'ISLAND' BETWEEN TXWYS K AND D AT SFO ARE DIFFICULT TO SEE AND MAY BE INOPERATIVE OR TOO DIM.

Narrative: I LANDED RWY 28L AND TAXIED CLEAR ON TXWY T AND TRANSITIONED TO TXWY D; HEADED FOR THE GATE. THE TXWY BORDER LIGHTS (BLUE) THAT NORMALLY OUTLINE THE 'ISLAND' THAT EXTENDS E AND W BETWEEN TXWY K AND TXWY D WERE EITHER NOT ILLUMINATED OR WERE TURNED DOWN SO LOW AS TO BE INVISIBLE IN DARKNESS. THE TXWY CTRLINE LIGHTS THAT LEAD INTO TXWY D FROM THE N WERE ALSO ONLY PARTIALLY ILLUMINATED; AND WENT DARK AS THE TXWY JOINED TXWY A AND THE RAMP. AS I TAXIED S ON TXWY D AND TURNED SLIGHTLY RIGHT (W) TO JOIN THE RAMP; I REALIZED THAT I HAD ACTUALLY ENTERED THE EASTERN END OF THE 'ISLAND.' THIS AREA IS ENTIRELY PAVED. MOST OF THE AREA IS PAINTED GREEN; EXCEPT FOR THE AREA THAT I TAXIED ON; WHICH IS UNPAINTED CONCRETE THAT APPEARS EXACTLY AS THE TXWYS. AN ADDITIONAL VISUAL CLUE THAT SFO HAS RUNNING THROUGH THE 'ISLANDS' THAT ARE PAVED IS A LINE OF VERTICAL PLASTIC 'PICKETS.' THIS UNLIGHTED UNPAINTED AREA WAS ALSO DEVOID OF 'PICKETS' ON THE EASTERN END (WHICH I TAXIED ACROSS). WE SMOOTHLY TRAVERSED THE EASTERN END OF THE 'ISLAND.' THERE WERE NO OBSTACLES OR FOREIGN OBJECTS IN THIS AREA THAT MIGHT HAVE PRESENTED A HAZARD TO THE ACFT; AND A THOROUGH POST FLT INSPECTION WAS COMPLETED (BY ME). UNDER SIMILAR NIGHT CONDITIONS THAT MIGHT INCLUDE A RESTRICTION TO VISIBILITY (RAIN ON THE PAVEMENT); I'M SURE THAT I WOULDN'T HAVE EVEN REALIZED THAT I HAD TRAVERSED THE 'ISLAND.'

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.