Shay Castle Profile picture
Mar 9 42 tweets 6 min read
Now a report on traffic/street safety in #Boulder.…
So much to report here.... basically, aside from 2020 (an anomaly), the number of crashes overall has declined in recent years but the number of crashes resulting in severe injury and/or death has stayed fairly consistent.
Boulder does a Safe Streets Report every 3 years that looks at crashes and trends

65% of severe crashes happen on arterial streets (larger ones) despite the fact that they make up a minority of all Boulder's streets
52% of bicycle-involved crashes on arterials
94% of left turn crashes on arterials
77% of ped-involved crashes on arterials

11% of crashes happen on local streets (tho they make up 54% of city network)
We may get into this later, as we talk about Boulder's new CAN focus (Core Arterial Network)
40% of crashes happen at signalized intersections
At least three per year at
- Foothills & Arapahoe
- 28th & Colorado
- Broadway & College & 14th
- S Broadway & Table Mesa
5,743 total crashes (1,914 per year on average)
151 severe crashes (3%, 50 per year on average)
14,500+ ppl involved in car accidents
9 ppl killed (2 walking, 1 bike, 6 in a car)
150 ppl seriously injured (25 walking, 55 on a bike, 70 in a car)
$275M+ societal cost
Most severe crashes involve
Left turns

Let's look at each of those (plus some other trends)
2% of all crashes
18% of severe crashes
77% in crosswalk (all crashes)
70% in crosswalk (severe crashes)
77% on arterials
Since 2009, 46% of ped crashes and 68% of severe ped crashes involve
- left-turning vehicles (26%, 11% of severe)
- ped dashing into traffic (12%, 30% severe) or
- car failing to yield in intersection (8%, 19% of severe)
The worst intersections for peds
- Baseline & Mohawk (4, 2 severe)
- Arap & 55th (3, 1 severe)
- Canyon & Boulder Main LIbrary (3, 1 severe)
6% of all crashes
36% of severe crashes

63% in crosswalk (all)
47% in crosswalk (severe)
20% intersection (all)
16% intersection (severe)
6% bike lane or paved shoulder (all)
14% bike lane or paved shoulder (severe)
52% were on arterials
Worst intersections for crashes involving bikes
- 28th & Colorado (9, one severe)
- Baseline & Canyon Creek Rd (7, two severe)
9% of total crashes
32% of severe crashes
33% of drivers were ages 20-25
78% of drivers were males (in severe speeding crashes)

Worst intersections
- Broadway & Regent (7)
- Broadway & Baseline (6)

Worst corridors
- Broadway
- 28th
- Arapahoe
Left turns
16% of all crashes
34% of severe crashes

Worst intersections
- Baseline & Mohawk (2 severe)
- S Broadway & Table Mesa (2 severe)
The city has made a lot of improvement here. Phasing changes at 25 intersections reduced crashes 87%. Those were made along:
Pearl Parkway
A couple other trends in crashes:

5% of all crashes
11% of severe crashes
71% of drivers were male (all)
84% of drivers were male (severe)
57% under the age of 30
24% between 30 and 49

Worst intersections
- Foothills & Arap (6, two severe)
- Valmont & Foothills (4)
And, interestingly enough given how young people are involved in a lot of crashes, staff ID'd the 65+ age group as a rising trend in crashes

65+ were involved in
17% of all crashes (but only 12% of population)
25% of severe crashes
In 54% of crashes with this age group, the 65+ person was at fault
We've already moved on to council questions, but I have more notes!
Benjamin asked about red light cameras.
Devin Joslin, principal traffic engineer, says they are "extremely effective" at deterring folks from running red lights. Or at least reducing crashes from folks running red lights.
I realized I didn't really define what Arterial roadways are other than to say they're the bigger, main streets.

That's true, but also: They typically have much higher speeds and many more lanes. So more opportunity for crashes and severe ones.
Speer asked about the age of victims in crashes that happen in local neighborhoods. The city didn't look at that, Joslin said, but they can.
That was in response to concerns about kids and speeding cars as the city turns its focus from speed management in neighborhoods to those arterials where the majority of severe crashes happen. Per council's direction.
More info on that coming in a story this week. (And later in this presentation, probably)
This all pertains to Vision Zero, Boulder's goal to eliminate all serious injury and death from car crashes (by reducing the number of crashes and eliminating the serious ones altogether).
Boulder adopted Vision Zero in 2009, so 13 years ago. Severe traffic crashes decreased until about 2016, and have really stayed steady since then. So not a lot of progress.

2009-2020: 675 serious injuries or deaths from car crashes in Boulder
Context is always helpful, so....

Nationwide, between 2015 and 2019 (2020 excluded due to COVID-19)
- 7% increase in total crashes
- 6% increase in vehicle miles traveled
- 3% increase in population
In Boulder, during that same time
- 13% decrease in total crashes
- 10% increase in vehicle miles traveled
- 2.4% increase in population
Why are we not really looking at 2020? Bc it was so freaking weird on car travel.

During 2020,
- VMT dropped 29%
- Total crashes dropped by nearly half
- Severe crashes fell by a third
- Ped, bicyclists and impaired driver crashes all decreased
So it's not really useful to look at when measuring long-term progress.
Council is betting that a focus on the arterial networks will further Vision Zero goals, bc so many of the severe crashes happen there.

You can learn more about CAN here.…
I haven't touched on Twenty is Plenty yet, but I've got NOTES.

Reminder: That's when the city lowered speed limits in neighborhoods from 25 to 20 mph
It did not decrease speeds in a statistically significant way
“Speeds remain largely unchanged," staff wrote, and in some places, increased (very, very slightly)
“Average speed increased slightly” from 21.57 mph to 21.9 mph (1.54%)
“There was a slight increase in the number and percent of vehicles traveling over 30 mph and 35 mph”
5.88% *fewer* cars traveling under 20 mph
1.99% cars driving over 30 mph and .46% above 35
That's not unusual. In 4 peer cities, the findings were all the same.

Portland and Eugene, Oregon
Cambridge, Mass
All 4 reduced residential speeds to 20mph
Portland, Cambridge and Seattle reduced arterials speeds by 5mph
None found significant reductions in speed
Much more important than speed limits is street design

As staff noted:
“Local streets that are wider and have a painted yellow centerline saw faster vehicle speeds than streets that were narrower and without a centerline.”
In those 4 peer cities, all now design streets to the target speed (20 mph) rather than what most drivers will actually drive.
V few comments from council on this one. They're already done! And I have more notes!
Rare is the day when I'm ready and wanting a council meeting to last longer. That one left me unsatisfied.
But I do plan to follow up with a story. If ya'll have any questions you'd like me to ask about this general topic, let me know. I've got an interview tomorrow a.m., with a story coming later this week.
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More from @shayshinecastle

Mar 9
I'm here! Another #Boulder city council meeting. Tonight: Board and commission nominations (with a public hearing) and discussion of traffic crashes / injuries + deaths, and efforts to prevent them.
The "official" name of that latter subject is Safe Streets Report (as in, a study Boulder does every ~3 years on crashes and trends) and Twenty is Plenty — the city's 2020 move to lower neighborhood speed limits to 20 mph
Lots of interesting data in that one.
Read 70 tweets
Mar 2
Yes, I am still here. Next: When will council return to chambers for meetings? COVID transmission is still high but falling pretty quickly.…
Apparently April 5 at the very earliest for council, and May 3 for the public. As you'll see in that presentation.
That would be for regular and special meetings only; study sessions would stay virtual.

And even in-person meetings would be hybrid, with some council members, staff and public able to participate remotely.
Read 19 tweets
Mar 2
Next up: Some updates on the city's lobbying agenda for the state leg. No presentation, but I've got a few notes so you know what Boulder is advocating for.
First up: Support expansion of behavioral health
No specific legislation yet, but Boulder likely to support
whatever gets proposed. Recommendations from a task force report introduced to the state leg.

They are as follows:
- Address the residential behavioral health needs of Colorado’s Native American Tribes. ($5 to $10M)

- Meet the needs of children, youth, and families through residential care, community services, and school and pediatric behavioral health care integrations. ($110.5 to $141.5M)
Read 39 tweets
Mar 2
Next up: A quick review of plans for a new Fire Station No. 3
That's being relocated out of the floodplain (30th/Arap)…
It's quite pricey: Last I checked (fall 2021) the budget was $23.5M — $11M *over* budget, primarily due to the high cost of land to build on ($9M for 2751 and 2875 30th St
That $11M is coming from the CCS extension

The new Fire Station No. 3 will have: "4 apparatus bays, administration offices, exercise, meeting, dining, and living room spaces along with bunk rooms for firefighters and administrative offices"…
Read 24 tweets
Mar 2
Council passing the consent agenda, which has a few interesting things on it: First, some changes to the Boulder Junction area.
30th Street from Pearl to Goose Creek (east side) Goose Creek to Valmont (east and west)
Removing on-street parking, “trees in grates” (will be replanted in strip)
Replace with 8-ft “streetscaping planting strip” and 10-ft sidewalk, protected bike lanes

Planning Board OK’d 5-0
Secondly, 2691 30th St - city purchasing for affordable housing
$4.75M total
- $2.2M already paid to seller for 2 yrs as Path to Home, winter homeless shelter will be credited to city
City owes $2.55M more
Read 6 tweets
Mar 2
OK, our crime update.
Presentation here:…
TLDR: Boulder has a lower rate of violent crime than the U.S. and Colorado, but a higher rate of property crime.

A few crimes have increased in recent years, as we'll talk about. But again: Overall, a low violent crime rate, even with the increases.
That's important bc all these graphs show an increase in crime (except for bike thefts). But in some cases, the numbers we're talking about are literally between 0 and 10, like robbery.
Read 67 tweets

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