Unusual Time-of-Day Signals

[Dirt Roads]

The time-of-day subthread (in the Double Permissive Left Turn thread) reminded me of a weird time-of-day signal in Hillsborough, North Carolina.  The traffic light on northbound NC-86 for "westbound" I-85 and Truck NC-86 has a simple four-head signal doghouse for the left turn.  NC-86 is still two lanes and during most of the day the signal follows a traditional three-phase R/G/Y sequence.  But after 4PM on weekdays, traffic from the "new" Walmart at Hampton Pointe starts getting crosswind with I-85 rush hour traffic out of Durham and an additional protected left turn phase is added at the beginning of the green phase (but only if the lineup is more than say 3 or 4 cars long).  This appears to be a great solution to the traffic problem, but I've never seen anything quite like it elsewhere.

When the "new" Walmart opened a little more than 17 years ago, you might as well have driven to Durham or Burlington to go to Walmart rather than try to get out of the parking lot in the late afternoon.  It took about a year for NCDOT to install the fix.  NC-86 was supposed to be widened and the overpass replaced as part of the I-85 six-lane widening scheduled for the mid-2000s, but the project is still nowhere in sight.

p.s.  This is the home of the infamous "Tolerance Ends" sign (intended for trucks trying to get around Hillsborough).  That was up before the new

[Amtrakprod]

Can you link the street view for the  interestion(s) talked about


iPhone

[1995hoo]

Pretty sure he means here: https://goo.gl/maps/dknPPPDTJEGohTi79

[Amtrakprod]

Pretty sure he means here: https://goo.gl/maps/dknPPPDTJEGohTi79

I thought so but the doghouse is a 5 section signal not 4 as OP said, so I was confused.


iPhone

[Dirt Roads]

Pretty sure he means here: https://goo.gl/maps/dknPPPDTJEGohTi79

Correct.

I thought so but the doghouse is a 5 section signal not 4 as OP said, so I was confused.

Most sorry for the confusion.  I have no memory of the "new" doghouse signal (even though I have been through this direction at least a dozen times this past week).  I used to have photographic memory, but I still see the simple straight four-head.  That being said, I can visually remember the prices posted at the BP Station on Friday, as well as the appearance of the new yacht at Merritt Marine across the road.

Anyhow, almost all of the signals around here (both District 7 and District 5) were upgraded to doghouses with flashing yellow permissive left turns about 3 or 4 years ago.

[jakeroot]

Cool thread. I'll be interested see how many examples show up.

This signal along East Pioneer, in Puyallup, WA, to the best of my knowledge, originally operated with a leading green arrow during peak hours and then permissive-only during off hours. With the construction of the bridge over the railway to the east (Shaw Road), it no longer has any green arrow option, and is permissive only 24/7/365 as there is much less traffic along this road.

The only other close thing I can think of, and to call it "time of day" might be a stretch, would be these signals along Commerce St in Tacoma, which use green arrows only when there is a trolley. The 4-section signals are bimodal.

[Amtrakprod]

The only other close thing I can think of, and to call it "time of day" might be a stretch, would be these signals along Commerce St in Tacoma, which use green arrows only when there is a trolley. The 4-section signals are bimodal.

I'd just call this a preempt indication.

Anyways your first example made me think of another light that must be time of day.
this signal in Lexington, MA. Despite having left-turning cars waiting in the left turn lane, and GridSmart Camera (shown here in a more modern view), only gives a leading left in the afternoon. It's weird and makes me forget that there is even a left turn signal there. Maybe Lexington could paint that there are 2 lanes there, and install a flashing yellow arrow on both sides (3 head on the other side). I think lagging lefts here could just be perfect.

[roadman65]

The left turn signals in most of Florida changes phase to either pre through or post through depending on time. Sometimes come to an intersection at 2PM one day and it's after, then come back 24 hours later to the same signal and it gives you the protected left before the through movement.

Then US 17 & 92 at Pleasant Hill Road in Kissimmee gives two left turn phases WB to SB during PM rush hours per one phase through and side road phases. Yes so much Poinciana clogs US 92 to warrant a left turn signal before the through phase and after the phase is ready to end for WB US 17 & 92.

[jay8g]

These two on Lake City Way in Seattle only use the protected phase during peak (as a leading semi-split phase). I really wish they would run more of the day, as those left turns can get backed up sometimes! I really wonder if this is somewhere where traffic would flow better by removing a through lane to provide dedicated left turn lanes.

[jakeroot]

These two on Lake City Way in Seattle only use the protected phase during peak (as a leading semi-split phase). I really wish they would run more of the day, as those left turns can get backed up sometimes! I really wonder if this is somewhere where traffic would flow better by removing a through lane to provide dedicated left turn lanes.

That's a great example. Totally forgot about it, since I'm hardly ever heading out that direction. You could conceivably designate a center turn lane along Lake City Way south from its current end-point, but with it mostly running diagonal through there, I think there'd be varying levels of demand for left turns depending on the angle of the intersection, which may ruin the point of the center turn lane apart from the few places where there are currently lots of demand. I think more creative signalization, perhaps using flashing yellow arrows within doghouses to allow lagging protected lefts, may be a good consideration for these couple of intersections.