Once upon a time plans for replacing 520 at Montlake Blvd aspired to get rid of the Hamlin Street U-turn — but no more — the U-turn is likely here to stay.
Despite adding a new intersection to Montlake Blvd south of Hamlin that allows northbound vehicles a direct left turn onto the westbound on-ramp, vehicles coming from Lake Washington Blvd via the Arboretum have no reasonable way to get into those left turn only lanes. Follow that? Here, have a look:
This turning maneuver is impractical, if not illegal. State law requires right turns to be made into the right-most lane* — and then signal for 100 feet of travel before merging left. That leaves about 40 feet for cars to aggressively merge across two lanes of traffic. WSDOT could install special exemption signs to make this easier (and legal) but would they? WSDOT spokesperson Suanne Pelley explains:
One of two things will occur… either motorists from Lake Washington Blvd will continue to be required to use the U-turn function at Hamlin or motorists from Lake Washington Blvd will be able to legally access the left turn lanes. RCW 46.61.290 (4) allows the City/State to modify the requirements for turning traffic for a particular intersection using signs or other traffic control devices, but we’re still working through the potential safety, efficiency and signal timing impacts of making such a change.
So make that a maybe. But given the expected increase in traffic on Montlake Blvd and its nine lane girth, allowing cars to merge hard left in such short distance would likely slow the whole system down. The Hamlin U-turn is out of the way, but it allows more time and space for Lake Washington Blvd traffic to weave left toward the U-turn lane.
Of course, with the plan as is, many drivers will try the hard left merge to save time — rules of the road be damned.
*The right most lane on Montlake Blvd will be transit only.