Narrative:

My father-in-law's C185 was just put on floats. I had offered to move it to his lake house. I saw the traffic was departing to the west off lake hood. This was noted due to the fact that an east departure would be beneficial to me and my ultimate destination. I taxied off the bank and proceeded to follow taxiing seaplanes in line for a west departure. After a couple of mins, lake hood tower called and asked if I knew that I crossed a controled north/south waterway, which I responded 'I did not know' and apologized. There are no markings or signs denoting this area. Seaplanes are parked all along the shoreline where I taxied. I would offer that lake hood at best is extremely confusing to pilots that are not familiar on a day-to-day operating basis with their rules of the water. Trying to apply surface taxi rules with all the lights, markings, and designated taxi areas and runways, cannot be rigidly applied to operation on an unmarked lake surface, as long as the operator/pilot is not in gross contradiction to existing traffic patterns at that time.

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Original NASA ASRS Text

Title: A C185 FLOAT PLANE PLT TAXIES ACROSS AN UNMARKED CTLED WATER LANE AND RECEIVES AN ADVISORY OF SAME BY THE CTLR AT LHD, AK.

Narrative: MY FATHER-IN-LAW'S C185 WAS JUST PUT ON FLOATS. I HAD OFFERED TO MOVE IT TO HIS LAKE HOUSE. I SAW THE TFC WAS DEPARTING TO THE W OFF LAKE HOOD. THIS WAS NOTED DUE TO THE FACT THAT AN E DEP WOULD BE BENEFICIAL TO ME AND MY ULTIMATE DEST. I TAXIED OFF THE BANK AND PROCEEDED TO FOLLOW TAXIING SEAPLANES IN LINE FOR A W DEP. AFTER A COUPLE OF MINS, LAKE HOOD TWR CALLED AND ASKED IF I KNEW THAT I CROSSED A CTLED N/S WATERWAY, WHICH I RESPONDED 'I DID NOT KNOW' AND APOLOGIZED. THERE ARE NO MARKINGS OR SIGNS DENOTING THIS AREA. SEAPLANES ARE PARKED ALL ALONG THE SHORELINE WHERE I TAXIED. I WOULD OFFER THAT LAKE HOOD AT BEST IS EXTREMELY CONFUSING TO PLTS THAT ARE NOT FAMILIAR ON A DAY-TO-DAY OPERATING BASIS WITH THEIR RULES OF THE WATER. TRYING TO APPLY SURFACE TAXI RULES WITH ALL THE LIGHTS, MARKINGS, AND DESIGNATED TAXI AREAS AND RWYS, CANNOT BE RIGIDLY APPLIED TO OP ON AN UNMARKED LAKE SURFACE, AS LONG AS THE OPERATOR/PLT IS NOT IN GROSS CONTRADICTION TO EXISTING TFC PATTERNS AT THAT TIME.

Data retrieved from NASA's ASRS site as of July 2007 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.