“For the first time any of us can remember, there were no backups on I-90 for the long holiday weekend.”

When I heard this earlier today from my colleague Mike in Union Gap, I was a bit skeptical. No backups on I-90, on a holiday weekend? In the summer? He had to be kidding.

Well, it’s true – compared to the three-day weekend in 2010, I-90 travel was down, but just a tiny bit. This year, we counted 200,810 vehicles both directions over Snoqualmie Pass, down 2,894 from last year. That’s only 1.4 percent.

It wasn’t that slim decrease that kept traffic moving all weekend. For the story, you need to check out what happened Sunday and Monday.

• On Sunday, we counted 36,491 vehicles over I-90, a 23.7 percent increase from 2010.


• Then, on Monday, there were only 34,474 going over the pass, a 30.2 percent decrease.

So, how did that help? And more importantly, how did that happen?

First, that helped because when you split traffic between two days (rather than everyone travelling the same day) you get what we saw on I-90 this weekend– no backups or delays. Half the people went Sunday and the other half Monday (more or less).

Nice.

As for how it happened – I’d like to think it’s because all the drivers used our travel graphs. Ya’ll did, right? But if not, if there’s some reservation system for who gets to drive when, will you let me know where to find it? I want to get my spot for Labor Day.

As for the other locations we track, our projections were pretty close. The traffic on I-5 near the Canadian border was up just a bit from 2010, about 7 percent. It must have been those Canada Day revelers. They may have then made their way over US 2 to Stevens Pass, as this route was also up 7 percent.

One place that did see a decrease was I-5 between Tacoma and Olympia. South Sound travel was down 3 percent, right about what AAA predicted.

There’s one mother who always gets her way. A mother that doesn’t seem to care about anyone’s plans, but her own. Yes, that’s her: Mother Nature.

And that was pretty evident over Thanksgiving weekend, when WSDOT’s traffic data shows 33 percent fewer drivers traveled over Snoqualmie Pass and 45 percent fewer traveled over Stevens Pass compared to the mild 2009 weather.

And those pre-Thanksgiving weather conditions, and lower travel numbers, weren’t just in the mountains. They also showed up in other places. On I-5 near the U.S./Canadian Border, there was a slight decrease (less than one percent) and through the Tacoma/Olympia area, there was a six percent decrease from 2009.

WSDOT tracks holiday travel in locations where travel increases significantly on long weekends. With its five-day break, Thanksgiving tends to see the most highway travelers of the year.

(Side note: let us know in the comment about your Thanksgiving route over the river and through the woods. We have the black and white data, but we're always looking for color commentary.)

In general, lower elevation areas saw decreased travel for the beginning days of the 2010 holiday weekend, and increased travel towards the end. This pattern also tends to favor weather as the key indicator, as the winter storm lost steam Thursday.

In the mountains, travel was down all weekend – as the snow hit hard most of the weekend, even into Sunday.

I-90 Snoqualmie Pass
For Wednesday through Sunday, 126,500 vehicles traveled I-90 over Snoqualmie Pass. This was a decrease of 62,800 vehicles (33 percent) compared to 2009.

• 11,400 fewer (25 percent) traveled Wednesday
• 8,700 fewer (36 percent) traveled Thursday
• 16,600 fewer (50 percent) traveled Friday
• 14,200 fewer (38 percent) traveled Saturday
• 11,900 fewer (24 percent) traveled on Sunday

US 2, Stevens Pass
For Wednesday through Sunday 17,100 vehicles traveled US 2 over Stevens Pass. This was a decrease of 14,200 vehicles (or 45 percent) compared to 2009.

• 2,100 fewer (38 percent) traveled Wednesday
• 1,500 fewer (41 percent) traveled Thursday
• 3,400 fewer (48 percent) traveled Friday
• 3,900 fewer (52 percent) traveled Saturday
• 3,200 fewer (44 percent) traveled Sunday

I-5, Bellingham to Canadian border
For Wednesday through Sunday, 139,800 vehicles traveled I-5 between Bellingham and the Canadian border. This was a decrease of 200 vehicles (less than one percent) compared to 2009.

• 607 fewer (2 percent) traveled Wednesday
• 5,000 fewer (23 percent) traveled Thursday
• 600 fewer (2 percent) traveled Friday
• 2,900 more (10 percent) traveled Saturday
• 3,100 more (11 percent) traveled Sunday

I-5, Olympia to Tacoma
For Wednesday through Sunday, 522,000 vehicles traveled I-5 between Olympia and Tacoma. This was a decrease of 35,600 vehicles (6 percent) compared to 2009.

• 24,500 fewer (18 percent) traveled Wednesday
• 4,800 fewer (5 percent) traveled Thursday
• 7,900 fewer (7 percent) traveled Friday
• 700 more (1 percent) traveled Saturday
• 1000 more (1 percent) traveled Sunday

While it didn’t quite reach the 10 percent AAA predicted, travel increased in most locations compared to Labor Day weekend 2009. I have no idea why we didn’t reach the 10 percent mark. The weather remains one theory. What’s yours?

Yes, those ferry boats were full. There was a backup on I-90 coming back into the Puget Sound area and through Olympia into Tacoma. But we have seen those most every weekend this summer. And the I-90 backup was stop-and-go, not the stop-and-stop we typically see on busy three-day weekends.

So, what’s the deal? One piece of happy news could be the answer. It seems there were no major traffic incidents at the locations we track for holiday travel. That alone kept traffic moving rather well.

Thanks. And, here are the official numbers.

Over I-90 Snoqualmie Pass, there was a slight increase in traffic volumes over Labor Day compared with 2009. Between Friday and Monday, 191,000 vehicles traveled both directions of Snoqualmie Pass, an increase of 4,000 vehicles, or 2 percent.

• 53,900 traveled Friday, with 200 (less than 1 percent) more vehicle traveling this year.
• 43,900 traveled Saturday, with 1,700 (4 percent) more vehicle traveling this year.
• 42,800 traveled Sunday, with 800 (2 percent) more vehicle traveling this year.
• 50,000 traveled Monday, with 1,100 (2 percent)

We also tracked traffic in three other locations. In comparison to 2009, on I-5 from Shoreline (north Seattle) to the U.S./Canadian border (for Friday through Monday) there were 140,700 vehicles on I-5, an 11,000 vehicles (or 9 percent) increase compared to 2009.

• 2,200 more (6 percent) traveled Friday.
• 2,900 more (9 percent) traveled Saturday.
• 3,500 more (11 percent) traveled Saturday
• 2,300 more (8 percent) traveled Monday.

There’s an equipment malfunction so no data on I-5, Olympia to Chehalis (Thurston/Lewis county line), but we can tell you what happened further north, between Olympia and Tacoma. We found the traffic was fairly normal for a summer weekend. And the volume was essentially unchanged compared to the same period in 2009. For Friday through Monday there were 446,000 vehicles on I-5. This was an increase of only 1,100 vehicles (0.2 percent) from 2009.

• 5,300 fewer (4 percent) traveled on Friday.
• 2,700 more (2 percent) traveled on Saturday.
• 6,400 more (7 percent) traveled on Saturday
• 2,700 fewer (3 percent) traveled on Monday.

We were unable to gather data for westbound US 2/Leavenworth to Stevens Pass this holiday weekend. For Friday through Monday there were 16,700 vehicles on eastbound US 2. This was an increase of 2,200 vehicles (or 15 percent) compared with the same period in 2009. And while this seems like a large jump, we didn’t have any backups Monday on westbound US 2 coming back.

Another hmmmmmmm. What’s your theory?

I hope you had a safe Independence Day weekend. Nice weather, good people, well-behaved children, minimal wait times. I hope you were lucky enough to have a few of those. Olympia was pretty cold, but we were lucky enough to stay dry.

If you were on Washington’s roadways, you should be able to say yes to one – those minimal wait times. The Washington State Ferries were very busy per usual, but for the most part, those of you travelling over the hills and through the woods didn’t face too much traffic.

Over I-90 Snoqualmie Pass, the number were very similar to Independence Day 2008 (also a three-day weekend - when Independence Day fell on a Friday), however there was a spike in Monday evening traffic.

• Close to 200,000 vehicles traveled both directions of Snoqualmie Pass between Thursday and Monday, nearly the same amount of vehicles as in 2008.
• Close to 50,000 traveled Monday, almost 10,000 more than in 2008. The heaviest traffic was from noon to 9 p.m.
• We noticed more drivers travelling later in the day, with a pretty large spike in the 8 p.m. hour. That’s a good thing, since spreading the traffic out over the day helps reduce backups during peak times, and more traveling later helped keep the delays to a minimum.

As for the other days on I-90 (also in comparison to 2008):

• 2,700 fewer vehicles traveled Friday.
• 3,800 fewer vehicles traveled Saturday.
• 4,500 fewer vehicles traveled Sunday.

We also track traffic in three other locations where we typically see an increase numbers on three-day weekends. In these locations, we are showing you the comparison to 2009, when Independence Day was a Saturday, not a three-day weekend.

On I-5 from Shoreline (north Seattle) to the U.S./Canadian border

• For Friday through Monday there were 167,000 vehicles. This was a decrease of 8,200 (5 percent) compared to the same period in 2009.
• 3,400 fewer vehicles traveled Thursday.
• 1,300 fewer traveled Friday.
• 2,000 fewer traveled Saturday.
• Sunday travel was unchanged from 2009.
• 1,600 fewer traveled Monday.

I-5, Olympia to Chehalis (Thurston/Lewis county line)
Unfortunately, we had technical problems here, losing a traffic loop. So at this location we were unable to do a comparison.

US 2, Stevens Pass
For Friday through Monday we counted a total of 39,700 vehicles on US 2. This was an increase of 4,000 vehicles (10 percent) compared with the same period in 2009.

• 1,000 more vehicles traveled on Thursday.
• 800 more vehicles traveled Friday.
• 1,100 more vehicles traveled Saturday.
• 500 more vehicles traveled Sunday.
• 600 more vehicles traveled Monday.

Interesting stuff…2010 actually shows lower volumes from 2009. And 2010 was a three-day state holiday. I wonder if it was the weather forecast. Or maybe everyone went somewhere else. The beach?