trb webinar: traffic trends and safety in a covid-19...

TRANSPORTATION RESEARCH BOARD

@NASEMTRB#TRBwebinar#COVID19

TRB Webinar: Traffic Trends and Safety in a COVID-19 World

June 2, 2020

Traffic Trends and Safety in a COVID-19 World

Fraser ShillingRoad Ecology CenterUniversity of California, Davishttps://roadecology.ucdavis.edu

Map-image from TRB Webinar, June 2, 2020

Acknowledgements

• First, this presentation is not intended to take away from the pain and losses that many in the US and world have suffered from the pandemic. I also want to acknowledge all who work everyday in health care (including my own wife)

• Thanks to TRB and staff (Elaine Ferrell et al.), the Pacific Southwest Region UTC at USC, my medical colleagues at UC Davis Medical Center (Drs. David Shatz & Christy Adams), and my epidemiology colleagues at the California Department of Public Health (Drs. Nana Tufuoh and Orion Stewart). Finally thanks to Dr. David Waetjen, analyst and web-guy extraordinaire

• Thanks to ITS-UCD, PSR-USC, and NCST for past and continuing support

Main Ideas

Covid-19 rapidly spread from multiple starting points in the US from February into MarchMany local jurisdictions and most states advised residents to “stay-at-home” or “shelter-in-place”Bay Region (6 counties) March 16, California March 20There was massive response to this guidance in the form of reduced driving and air travelThere were multiple outcomes from this sudden change in travel

“Silver” Linings

Silver -- Reduced traffic and crashesGreen/Gold -- Reduced traffic and costsBlue -- Reduced traffic and improved air quality/climate

More information at https://roadecology.ucdavis.edu

CA – Traffic

Traffic volumes on highways (peak veh/hour) reduced 20-60% within 2 weeks

Variation among highways, some with very little reduction

Source: PeMS.dot.ca.gov

Traffic

CA -- Counties

Traffic volumes (VMT) declined ~80% in certain counties from early March to mid-April, then started to climb

Source: streetlightdata.com

Traffic

March 20

March 20March 20

CA – Counties

Not all counties responded the same


Traffic

March 20

March 20

March 16 & 20

US – Counties

This is reflected to varying degrees throughout US, from Autauga, AL to Weston, WY


Traffic

April 5 - 30

March 19 – April 30

VMT reduction

CA – Traffic SpeedSpeeds measured by Caltrans sensors only recorded slight increases in most drivers’ speed, in contrast to news reports on excessive speeding

HIGHWAY PEAK SPEED CHANGE 95TH/99TH (MPH)

AVERAGE SPEED CHANGE (MPH)

I-80 (NV BORDER) +1/0 +3.8 US99 (S OF YUBA CITY) 0/1 +0.2 (n.s.) I280 (DALY CITY) +1/2 +1.6 SR46 (E OF SLO) +1/2 +0.6 SR88 (IONE) +1.2/3 +1.3 SR49 (MARIPOSA) +2/1.2 +0.2 (n.s.) US101 (SLO) +0.6/1 -1.6 I-405 (COSTA MESA) +2/2 +3.5 SR91 (ANAHEIM HILLS) +0/1 -1.2 (n.s.) I-5 (OCEANSIDE) +2/2 +0.7 (n.s.) I-10 (PALM SPRINGS) +1/1 -0.12 (n.s.)

Traffic

I-405

US 101

CA – Crash

Rain events

Traffic crashes of all kinds and injury/fatal declined ~50% within 2 weeks (on state highways)

Variation among regions, and a major impact from rain events

Source: CHIPS – a custom system

Traffic-Safety

Trauma Center Independent Confirmation

Sacramento regional hospitals reported 38% reduction in injuries in/on vehicles (auto/truck/MC) and 46% reduction in injuries to pedestrians and cyclists between early March and mid-AprilThere was no difference between early March 2019 and mid-April 2019

(preliminary results)

Traffic-Safety

CA – Crash Distribution

March 1-14, 2020 (12,990 crashes) April 1-14, 2020 (7962 crashes)Traffic-Safety

Reductions in crashes were evenly distributed throughout state

CA – Crash Costs

Pre-Order (2/27 -3/19)

Post-Order (3/21 -4/11)

Sum Cost $3,065,761,260 $2,180,039,440Daily Cost $139,352,785 $99,092,702

Based on crash-cost coefficients from FHWA (2018)

All property-damage only, minor/major/unknown injury, and fatal outcomes on state highways (~1/3 of state total) summed pre and post-order

CA “saved” $40 million/day in crash-related costs after the order>$2 billion saved since order.

Fuel Use and Revenue

Pre-Order (3/2-8) Post-Order (4/11 - 4/17)Fuel Use 349 million gal 85.8 million gal Tax Revenue $213 million $52.3 million

All travel (VMT) converted to equivalent fuel based upon US automobile fleet average fuel consumption (22.3 miles/gal)

US driving reduction saved drivers $8.6 billion/week in fuel purchase, but cost US states $1.2 billion/week in fuel tax revenue. In CA >$1.3 billion lower tax revenue since order (3/21-5/16)

Conclusion

After “shelter-in-place”Total travel in US dropped 71% between early March and mid-April, in CA the decline was 75%CA crashes on state highways were reduced about 50% per week, except during an exceptional rain eventCosts associated with crashes on highways in CA declined ~$40 million/day, >$2.2 billion in 8 weeks since order (Total will be higher)Fuel tax revenues in CA declined >$1.3 billion in 8 weeks after orderSavings from reduced crashes almost twice loss in tax revenue

Contact [email protected]://roadecology.ucdavis.edu

Effects of COVID-19 Shutdown on Crashes and Travel in NCDaniel Carter, NCDOTTRB Webinar, June 2, 2020

NC Shutdown Timeline

2

March 10 Governor declares state of emergency.

March 14,15 NC closes schools; bans gatherings exceeding 100 people. Many churches start holding remote services.

March 24 Counties begin issuing stay-at-home orders.

March 27 Governor issues stay-at-home order for the state.

May 8 Governor lifts some restrictions (Phase 1, retail stores, child care).

May 22 Governor lifts more restrictions (Phase 2, businesses, restaurants, larger venues).

Traffic Volume Trends

3

Speed Trends

4

Speeds increased from significantly below speed limit to slightly abovespeed limit (elimination of congestion)

Very little change; speeds before shutdown were already close to speed limit (free flow)

NOTE: Data from 4:00-6:00pm on weekdays

Crash Trends

5

Preliminary data

Crash Trends

6Preliminary data

Crash Trends

7Preliminary data

Crash Trends• Total crashes decreased by 50%• Fatal crashes decreased by 10%• Fatal + A-injury crashes increased by 6%

Why the difference?– Speed?– Single vehicle vs. multi-vehicle crashes?

8

Crash Trends

9Preliminary data

Crash Trends

10

Total Crashes by Relation to Speeding (Exceeded Speed Limit)

Crash Trends

11Preliminary data

Crash Trends

12

Fatal and Serious Injury (F&A) Crashes by Number of Vehicles

Takeaway Points• Traffic volume decreased significantly

(40%) due to the shutdown but is climbing back up.

• Travel in urban areas decreased more than travel in rural areas.

• Weekday evening interstate speeds increased in congested urban areas but hardly changed in rural areas.

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Takeaway Points• Major reductions in total crashes (50%) • Moderate reductions in fatal crashes

(10%) • Small increases in fatal and serious injury

crashes (6%)• Difference seems to be related to the

higher proportion of single-vehicle crashes but not strongly related to higher speeds.

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Contact Info

Daniel CarterNorth Carolina DOT, Traffic Safety Unit

[email protected]

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TRB WEBINAR: TRAFFIC TRENDS AND SAFETY IN A COVID-19 WORLD

VDOT StaffMena Lockwood, P.E. – Assistant State Traffic Engineer Sanhita Lahiri, P.E., PTOE – Data & System Analysis ManagerSimona Babiceanu – Data Scientist

What is happening in Virginia?

June 2, 2020

Traffic Trends and Safety in a COVID-19 World – Virginia

Virginia – at a Glance

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• All public roads: 70,393 miles• State maintained roads: 57,867-miles• Inland waterways: 674 miles• Public use airports: 66 • Automobiles registered: 3.9 million• Light trucks registered: 2.0 million• Heavy trucks registered: 34,000• Buses registered: 18,000 • Motorcycles registered: 61,000

Nine VDOT DistrictsFive Regional Traffic Operations Centers2018 VMTs: 85,333,510,600


Traffic Monitoring System (TMS)

3

TMS Produces VA’s Source System of Record (SSR) for: • AADTs for 20,000 traffic links • Vehicle Miles of Travel (VMT) for 120,000

links

TMS Scope of Program:

512 Continuous Count Stations•306 Road Sensors (CCS)•206 Non-Intrusive (Radar) Sensors (NCCS)20,000 48 Hour Count Locations


Corresponding Questions:• Can we increase the allowable

work hours for closing lanes?• Are Virginians staying at home?• Have truck volumes decreased in

non-attainment areas?• How fast are volumes increasing

and when will lane closures need to be restricted again?! (need to know 2 week projection)

• Media: What is traffic doing in my area?

4

State of Emergency and Other Governor ActionsDate Governor Action

March 7 First Confirmed COVID Case in Virginia

March 12 Declares state of emergency

March 13 Closes schools for two weeks, beginning 3/16

March 17

Advises to avoid non-essential gatherings of more than 10, Self-quarantine if 65+ with chronic health conditions, Directs restaurants, fitness centers and theaters to reduce capacity to 10

March 20State agencies begin process of implementing telework where possible/applicable

March 23Closes schools for remainder of school year, Orders non-essential businesses to close, Bans gatherings of more than 10, Closes restaurant dining rooms

March 25 Directs hospitals to stop elective surgeries

March 30 Issues statewide stay-at-home order until June 10

April 15Governor extended closing of non-essential businesses for two more weeks

May 15 Some businesses reopen with enhanced safety measures


Track Traffic Trends in Virginia

Volume

Speed

Incidents

Decision Support During Pandemic Influence Phase

5

Traffic Trends and Safety in a COVID-19 World – Virginia 6

Volume Trends on Continuous Count Station volume

1 2 3 4 5 6 7 8 9 10

# Date Governor Action1 3/12/2020 Declares state of emergency2 3/13/2020 Closes schools for two weeks,

beginning 3/163 3/17/2020 Avoid gatherings of more than

10, Self-quarantine if 65+ with chronic health conditions

4 3/20/2020 State agencies begin process of implementing telework where possible/applicable

5 3/23/2020 Close school for till end of school year. Close non-essential businesses, restaurants & dining rooms. Gatherings of more than 10 banned

6 3/25/2020 Directs hospitals to stop elective surgeries

7 3/30/2020 Issues statewide stay-at-home order until June 10

8 5/09/2020 Phase One will begin no sooner than Friday, 05/15

9 5/12/2020 Delays Phase One for Northern Virginia Localities till 05/28

10 5/14/2020 Delays Phase One for Accomack County and the City of Richmond till 05/28


Statewide All Vehicle Hourly Volume during Peak Hours

7


A multiple regression line is used to project forward Volumes to help in near term decision making


All Vehicle Daily Volume by District

8


Lynchburg

NOVA

Fredericksburg


Truck Daily Volume by District

9



All Vehicle Daily Volume by Area and Roadway Type

10



Example: Allowable Work Hours volume

MARCH APRILMARCH APRIL

Year 2019: I-81 NB MM 87 – MM 104Year 2020: I-81 NB MM 87 – MM 104


Example: Lift Lane Closures volumeVolumes

were Forecasted to get a range of expected traffic during Memorial Day Weekend


Speed Trends Based on INRIX Data speed# Date Governor Action1 3/12/2020 Declares state of emergency2 3/13/2020 Closes schools for two

weeks, beginning 3/163 3/17/2020 Avoid gatherings of more

than 10, Self-quarantine if 65+ with chronic health conditions

4 3/20/2020 State agencies begin process of implementing telework where possible/applicable

5 3/23/2020 Close school for till end of school year. Close non-essential businesses, restaurants & dining rooms. Gatherings of more than 10 banned

6 3/25/2020 Directs hospitals to stop elective surgeries

7 3/30/2020 Issues statewide stay-at-home order until June 10

8 5/09/2020 Phase One will begin no sooner than Friday, 05/15

9 5/12/2020 Delays Phase One for Northern Virginia Localities till 05/28

10 5/14/2020 Delays Phase One for Accomack County and the City of Richmond till 05/28

Note: The direction with the lowest speed is shown

Example: Northern Virginia


Speed Trends Based on INRIX Data speedExample:

Northern Virginia


Incident Trends Based on WAZE Data incident


Preliminary data indicates that during the period of March 13, 2020 through April 30, 2020:• Speed-related crashes account for more than 23% of total

crashes during the time period, which is an increase over the same period last year (18.5%), and higher than the 5-year average (19%).

• Speed-related fatalities make up approximately 48% of overall fatalities during this time period, which is a higher percentage than the 5-year average of 41%.

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Records from DMV safety


Weekly Traffic Crash in Virginia safety


Example of Actions Taken safety


Virginia COVID-19 Traffic Trend Tool tool

Trends are tracked since 01-Jan-2020

https://public.tableau.com/profile/simona.babiceanu#!/vizhome/COVID-19VirginiaTrafficVolumes/ByLinkidDir


Volume Data tool• Vehicle Types

• All Vehicles• Cars (motorcycles, passenger

cars, pickups & vans)• Trucks (rest of the vehicle

classes)• Actual data collected is used

• No imputation• Data is processed by direction for 893 locations (733 links)


Volume Data Processing tool• Process historical (2019) data

• Only quality controlled data used• Computation –

• Average hourly volumes by month, DOW, period of day for typical day

• Holiday periods (New Year, Memorial Day, etc.) calculated separately

• Process current (2020) data• All available data used• Computation –

• Average hourly volumes for 24hrs for the Date

• Percent Volume Change computed bycomparing with corresponding 2019 data

Non Holiday Dates compared with 2019 typical dayHoliday period compared with same holiday in 2019


Volume Data Processing tool• Aggregation Levels

• Hourly• Average Peak Hour –

• AM (7-9 AM), Mid-day (11 AM – 1 PM), PM (4-6 PM)

• Overnight (10 PM – 6 AM)• Daily

• Attributes• Vehicle Type• District• Jurisdiction• Road Type (Interstate/ Non-

Interstate)• Area Type (Rural/Urban)• Location


• Data• Volume:

• Approx. 19.5 K records/day or 600 K records/month (120 MB)

• Vehicle Class: • Approx. 8.5 K records/day or 250 K

records/month (77 MB) • District Level (as of 05/26/20):

• 0.5 million records (33MB)• Jurisdiction Level (as of 05/26/20):

• 1.5 million records (132MB)• Location Level (as of 05/26/20):

• 6.3 million records (730MB)

• Processing Environment • Processing is automated

• Oracle SQL, R, Python, Tableau

• Tableau application hosted on Public Tableau server• Packaged Tableau file with data

extracts published to server• File size 30 MB (as of 05/26/20):

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Volume Data Processing (Contd…) tool

Questions?

Mena Lockwood, P.E.Assistant State Traffic Engineer804.786.7779 || [email protected]

Sanhita Lahiri, P.E., PTOEData and System Analysis Manager804.786.1287 || [email protected]

Simona Babiceanu Data Scientist804.729.6268 || [email protected]

Fraser Shilling,Road Ecology Center (UC Davis)

Daniel Carter,North Carolina DOT

Sanhita Lahiri,Virginia DOT

Mena Lockwood,Virginia DOT

Webinar Presenters

TRB Resources• Renewing the National Commitment to the Interstate

Highway System: A Foundation for the Future• NCHRP Research Report 932: A Research Roadmap

for Transportation and Public Health• NCHRP Research Report 928: Identification of Factors

Contributing to the Decline of Traffic Fatalities in the United States from 2008 to 2012

• NCHRP Research Report 875: Guidance for Evaluating the Safety Impacts of Intersection Sight Distance

• NCHRP Synthesis Report 535: Pedestrian Safety Relative to Traffic-Speed Management

Get Involved with TRB• Getting involved is free!

• Join a Standing Committee (http://bit.ly/TRBstandingcommittee)

• Become a Friend of a Committee (http://bit.ly/TRBcommittees)– Networking opportunities– May provide a path to become a

Standing Committee member

• For more information: www.mytrb.org– Create your account– Update your profile

@NASEMTRB

@NASEMTRB

Transportation Research Board

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trb webinar: traffic trends and safety in a covid-19...

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