Air carrier flight crew reported an incorrect depiction of hold short lines at DCA coupled with confusing ATC instructions resulted in the aircraft crossing hold short lines creating a runway incursion.

Reporter 1

After landing at DCA, we were instructed to leave Runway 01 via Taxiway S, then to continue via Taxiway J to the HOLD BAY 19. We were subsequently instructed to make a left turn, to continue via Taxiway K and hold short Runway 33. In that position we maintained until they gave us instructions to continue to our ramp. When we arrived at the ramp, the gate agent gave us the Control Tower's phone number, informing me that ATC wanted to talk to me. The person who answered my call told me that they had seen the video of our airplane after landing and that unfortunately we went over the HOLD LINE on Taxiway S, I explained to him that the instruction was to taxi via Taxiway k, I told him that two HOLD LINES are depicted on the Jeppesen Airport Moving Map, and it seems that both HOLD LINES refer to Taxiway S and Runway 33. As soon as we arrived at the beginning of Taxiway K, we stopped the airplane following the instructions that ATC gave us. We stopped the airplane between Taxiway S and Taxiway K. Until that moment everything seemed to be in accordance with the instructions received, nobody told us that we had done something wrong; no plane had to reject the takeoff or do a go around because [of] us. At the end, the person from the Control Tower told me that they were going to investigate and asked for my phone number to contact me. Cause: The instruction received was not appropriate, the Controller should have told us to hold before Taxiway S, or instruct us to turn left and continue along Taxiway S and then Taxiway K. When taxiing from bay 19 to Taxiway K the hold marking lines were not in front of us, they were more likely to be seen to our left and it was clear that they are there to avoid crossing Runway 33 through Taxiway S and not through Taxiway K. Suggestions: The holding line markings should be perpendicular to the taxi line coming from hold bay 19, but from my view one was parallel to my line and the other one was diagonal to my taxi line, that is confusing specially if you are focus looking for the Taxiway K.

Reporter 2

After completing the Mt Vernon visual runway 01 we taxied off the active runway with a left turn on Sierra with instructions from tower to taxi to “19” holding pad. Immediately after turning right off of taxiway Sierra we were instructed to turn left into the pad, then following read back instructions we were told to continue left turn in the holding pad to face south. Subsequently commanded to “hold short of Runway 33 via Kilo.” So we taxied south across the hold short line on Sierra to converge onto Kilo where we stopped our aircraft following the exact command from tower holding short of Runway 33 on Taxiway Kilo and waited further instructions. Moments later instructed to taxi across Runway 33 to rejoin Kilo and turn right onto November. After that command also told to copy down Washington Tower telephone number. After a successful read back we continued to taxi as instructed to holding pad 15, waiting for our gate to become free. No go arounds or instructions to other aircraft as result. Cause: Wrongly depicted taxi diagram, nonstandard phraseology from tower, incorrect taxi instructions. Suggestions: Fix taxi diagram at DCA.