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Aysha Rüya Cohen

877 days ago
Unfiled. Edited by Aysha Rüya Cohen 877 days ago
Aysha C Notes: Compiled by: Aysha Cohen, UCLA Institute of Transportation Studies Scholar (@AyshaRuyaCohen or www.Linkedin.com/in/AyshaRuyaCohen)
 
  • Problems:
  • By the time traffic gets to trafficked areas it fans out - i.e. “regional congestion by a thousand cuts” - 
  • To LOS ped/cyclists are obstructions to transportation - 
  • Denver - LOS shows failure even when there is success - travel times decrease even as delays increase? 
  • Bray’s paradox - worse congestion downstream in bottle necks
  • Building to LOS forces more road constructure than it can afford to maintain 
  • Hard to calculate and inaccurate 
  • Leads to - see slide
  • VMT:
  • See slide 
  • Mitigating VMT helps maintain small town character 
  • VMT doesn't tell us about the function of the transportation network, but it is a good way to measure transportation & environmental impacts, move to measures of access / connectivity instead of LOS 
  • Spectrum:
  • Word = what CA had - it misaligns the playing field for infill development - 
  • not fair - outside vs. inside 
  • Bring access
 
  • CA Law:
  • AB 32 said climate change is real, needs to be addressed - SB 743 - 
  • LOS in comprehensive planning, impact fees etc. but trying to balance the playing field
  • 40% of public space dedicated to driving/storing a car
  • Before - common land use plan traditional - maps created show function class - sized to a LOS threshold - for peak 15 min of the peak hour - LOS - few community members can therefore afford to maintain roads they have already built - (roads are wider than needed)
  • VMT lens - optimize the amount of VMT in each community, iterative - what we can afford to build
  • Public infrastructure should be well utilized - from an economist perspective - balanced to the externality
  • VMT = volume or trips x distance 
  • how are you going to measure it 
  • how are you going to determine what is acceptable levels of VMT - thresholds
  • CA -all trips in and out of the community, big data from mobile devices etc. to sample VMT from diff land uses - green are, you’re an infill project
  • e.g. Yolo County - General Plan set a threshold - 44 ?
  • LOS lens - the only mitigation is to expand the intersection/lanes - storm water, crossing, heat island etc. - not external impact but 
 
  • Q&A: 
  • environmental review law - local jurisdictions can use police powers with LOS - not the knee jerk reaction though - 
  • identified potential areas in the 20 years - forecasted  
  • e.g. Pasadena - dealing with infill - a parcel here and there - road network done so the consequences of development project is focused on - so VMT is more meaningful than LOS
  • Bike and ped thresholds and VMT communities already adopted 
  • It will take about a decade for others who are more - status quo
  • co-benefits - the cost one resonates - cost is near top, greenhouse gas #39 in central valley?
 
  • mxd - captures density, - US EPA website - calibrated for San Diego - trip length, - smart location database - for vmt by employees - spreadsheets to calculated vmt on a project scale - 4 step accessibility model - 
  • See handbook from - VMT by itself, access to destinations (# of jobs in a 45 minate commute) 
  • UK has a similar 1997 - from our learnings it took about 10 years to see local pragmatic plans 
 
  • if you just have to analyze VMT and not LOS it is $20,000 to $200,000 -but now they propose what they want and deal with the impacts - this may change more fundamentally their design
 
  • e.g. Massachusetts - changes based on context - rural v urban
  • CA - guidance on thresholds that carries weight because CEQA is a litigious law
  • Bikeshare - bike system has to accommodate the cars in LOS system trying to build a body of data to defend - the accessibility needs - relative worth is not relevant - these gains - gate keeping measure - not in LOS
  • the accuracy of forecasting- LOS the left turn volume predicted fof 40 years in the - intersection forecasting for 2040 - fundamental - expected not road 
  • SB 743 on Fehr & Peers- eBook on LOS 
  • Other metrics considered (vehicle hours traveled etc) but VMT used - measures of access to destinations - looking for environmental impacts from transportation - ceqa - 
  • reducing vmt - need to implement TDM or ?? 
  • person miles traveled (PMT) per lane mile - scale of efficiency, you can throw in density as well? - Oregon and Washington are on the list
  • ceqa - easy and cheap to bring a lawsuit, tie up project in court -
  • Level of service measures for lack of delay during the busiest 15 mins of the busiest hour. 
  • Level of efficiency would measure how many vehicles use the road per day per lane. 
  • SB 375 - regional transportation plan and sustainable transportation strategy (land use/transportation) chapter added - 
 
  • Mitigation moderating required - can’t exceed a certain VMT threshold - under the 44 threshold have to do surveys - if not meeting it - influences physical design and then TDM strategies layered on til they demonstrate they can achieve and maintain that threshold Induced Travel: 
  • Components of Induced VMT -: 
  • Original VMT v Induced VMT
  • In the midterm ppl will move their house and VMT
  • Modeshift (automobile to transit
  • Newly generated trips - home-cooked meal decides ot go to a restaurant
  • route changes - can go either way
  • disperse land use = development 
  • Can you add capacity for As decrease travel times for the Bs as well?
  • Research:
  • See slide - 95% that there is induced travel (inconvenient truth, Part 2?)
  • 10% to the lane miles added, get more than 10% VMT - if the lane miles go
 
  • Induced Demand Denial widespread in departments - analogy/image metaphor needed to convey it to ppl - solving expanding waistlines by buying a longer belt (todd litman) 
  • Gainesville FL mayor on twitter = skeptical about induced demand for road diet
  • Todd Litman - on the ITE discussion group last week - debate was whether it existed
  • To make it more clear - inter city roadway capacity expansion - additional lanes on congested urban corridors - that will virtually always have induced travel - the mechanism by which induced travel comes with increased speeds 
  • e.g. Langston Parkway - Utah Dept of Transportation - understatedd the impacts, overstated the congestion impacts
  • No feedback for trip generation found
  • They don’t believe induced travel exists in practice - just population and job growth - FHWA and Utah Dept of Transportation (settlement agreement hired F&H > narrowed down to 30, 20 relevant to freeways/highways)
  • In US, you overstate the congestion relief benefits - 
  • Bankers contest it abroad, environmentalists question it at home
 
  • Time frame you’re doing the analysis - only how you do long term analysis - 20 years ago TRB study concluded that you could not predict sig increases in air pollution - biased the analysis with 2 year study - special TRB committee commissioned - failed to look at long term effects
 
  • Fehr & Peers:
  • HOV converted to HOT in Virginia - added more lanes to toll lane - robert bane standard poor - toll vs. non toll 
  • Induced and suppressed travel - for road diet travel
  • causality - phased in 10 year chunks bc of financial constraints 
  • build projects in small chunks - so did you accommodate planned growth or did you induced that demand? 
  • Benchmarks - 
  • Dynamic validation -model can % change in lane miles, % change to VMT
  • Example: Lawsuit came in - Alaska - replace ferry service with new roads - amount of induced travel? - examine from back end - access to major rivers with diff types of fish - induced more fishing - inducing activities as well not just in land use terms - that is not in the model 
 
  • TDM perspective - 
  • Govt invests in infrastructure - suppressed travel = suppressed activity - scary thing for economic development/policy folks - how to explain it - a question of how to get the most efficient economic activity
  • we treated congestion as a problem but it is a symptom - freeway lanes - throughput in peak periods less - lot of inefficiency built into the system - lane not well utilized at 1200 or 1300 not what the theoretical capacity would suggest (2200?) 
  • Reduce the amount ppl need to drive - do the same things, drive less to do it
...
877 days ago
Unfiled. Edited by Aysha Rüya Cohen 877 days ago
Aysha C *Compiled by: Aysha Cohen, UCLA Institute of Transportation Studies 
(@AyshaRuyaCohen, www.Linkedin.com/in/AyshaRuyaCohen)*  
  • Fare Structures:
  • Per Ride:
  • Distance based (operations)
  • Operations stand-point, it makes the most sense
  • Congestion based 
  • Zonal
  • Off-Peak Flat
  • Fat (öne city one fare”)
  • Payment Structures:
  • More expensive to less: Per Ride, Daily, Monthly, Annual, annual w/monthly payment
  • All you can eat bikeshare model - DC - Darren Buck (DDOT) advocates:
  • Ridership is primary outcome - behavioral economics -> switch from fixed cost to variable, get a decrease in activity - uncertainty - variable costs through space, time -measure of success high
  • They have the financial sustainability - creates ad revenue, creates short term tourist preferences - proposed a small price increase for annual subscribers
  • Ridership - buffet model -> more monthly/weekly passes
  • e.g. Hubway in Boston
  • It is very inexpensive, less than $100 - if you allow that peak heavy use, you have to pay for the cost of addressing it - 4 trucks can only hold 100 bikes (bicycle is a single occupancy vehicle, storage & security issues)
  • e.g. Philadelphia - $15 a month for bikeshare - reoccurs - so you can save in winter months when you are less likely to use bikeshare
  • Per Ride (CaBi Arlington advocates):
  • Flat fare for megausers, per trip fare pass - better for tourists ($2 for trip v $7 day pass (taxi price) - variety of fare types for those with different needs (e.g. those in Fairfax who use Cabi only on weekends)
  • Data shows increase in public and private bike usage
  • Discounted rate for transit users as last mile - treat it as one trip
  • Bikeshare takes some people from transit, replaces walking trips - of value to the pedestrian - moves 3x as fast 
  • e.g. University of Maryland - net increase in transit ridership - the rides bikeshare takes away from transit are the least productive ones (short ride, dwell time higher than travel time) 
  • Replacing more cab trips than single occupancy vehicle trips 
  • Market segmentation studies show that people who drive are less likely to switch overall than those who already use alternative transit
  • Transit agency rep says: Please take my trip"s - anything that enables a robust car-lite system - the more options you have the more people you will suck into it 
  • Visibility for that type of car-lite lifestyle - initial visibility and adoption level - so it is more pervasive - with investment - then structure fair differently - - 
  • When more costs of driving are variable, motorists will cut driving 
  • Tourists - short time frame - highest use per dollar you can get vs. NYC buying a longer term pass and using it a ton because they live there
  • Goals:
  • Mode share/ridership
  • Quality Service
  • Financial Stability / cost recovery 
  • Equity 
  • Virtual Cycle multi-modal/car-lite lifestyle 
  • DC compatibility with payment on Metro - if transit is slower, less convenient, for exercise, to cover the last mile of a trip
  • Smart Trip card payment for bikeshare- people tap and go - not experiencing the full cost-  until hit max fare - like getting in a car not thinking about the gas that you paid already
  • Under-employed people - 
  • Financial incentive to return bikeshare bikes - like returning your rental car to the airport gets $ back
  • e.g. Make a dollar from parking bikeshare bikes to help "balance" the system
  • As a post process - not in the current operations - if you go online to get reimbursed for delays but charged at the time 
  • Payment structure/mechanism hides the true cost of the trip - people don’t weigh each trip based on the fare structure - so they make shorter trips (michael and larry?)  
  • Workers not offered commuter subsidies are more price sensitive 
  • Lower income cross subsidize people with a higher income that can afford yearly rate
  • Making a cap - once you hit the amount of $ for the pass, you hit a cap for people who are “mobility insecure” 
  • e.g. London tube is expensive but a bunch of trips are capped at 4 pounds, not getting infinitely higher 
  • e.g. Residents of Talen, Estonia have free transit, but outsiders pay - equity issue 
  • e.g. Seattle - low income fare that also applies to bikeshare - 
  • e.g. Portland - corporate pass - unemployed - heavily discounted transit pass to non-profits to distribute to low income people 
  • e.g. WMATA - surcharge on paper fair cards - smart trip cards given to non-profits to distribute 
  • e.g. Verizon lifeline - paperwork to agency, like a senior pass for low income - different color fob perhaps?
  • People are willing to pay more for bikeshare, but 20% can’t afford it - holds fare down - make sure they get a discount 
  • Darren buck - capstone on membership for low income populations 
  • Barriers to bikeshare may be more than the cost of membership in Boston? - need to securitize - credit/debit card membership 
  • Bank on DC - $50 annual membership - debit/card with 5 banks given - many prefer check cashing - allowing for cash - county can vouch for its residents - in the works in Arlington now -
  • Quality of service -95% use smart trip on bus, so no surcharge on buses in WMATA - no paper transfers - electronics payment program - at bikeshare stations - arlington / wmata
 
 
888 days ago
Unfiled. Edited by Aysha Rüya Cohen 888 days ago
Background
Some places Right-on-Red allowed unless signed otherwise.  Some places Right-on-Red allowed only when signed.  Internationally often fully prohibited.  Came about in the US during the 1970s Oil Crisis to save gas as people wouldn't have to use as much gasoline while waiting to turn. Minimal research on Right on Red, most of it old, says Right on Red is safe because it causes few crashes.  Need more research. 
Aysha C
  • Across jurisdictions, the rule changes, making it confusing for drivers
  • e.g. New Jersey vs. NYC signage say opposite rules
  • Back up of cars at next intersection is why NYC does not allow Right on Red instead otherwise noted (?) 
  • There is a fight for bikes to have a Right on Red internationally currently
 
The Problem
Right turning cars are approaching from behind the pedestrians and cyclists crossing in the crosswalk.  In many suburban and rural areas, drivers are used to driving exclusively where there are few pedestrians and cyclists to look for. Perhaps the prevalence of slip-lanes have habituated many drivers to the idea that you don't have to stop before turning right on red. In addition to causing crashes, it is a barrier to getting people to walk.  It causes uncertainty, it causes people to feel that things are unsafe leading to fewer people walking.
  • Misleading data on Right on Red- 
  • If less people will try to cross at dangerous intersections, there are less data points
  • Crash data is misleading - does not count near-misses (?)
 
School Crossing - Example
  • Design Flaws = 
  • Right turn "Slip Lane" - Wide turning radius has habituated drivers to not come to full stop with splitter (?) island
  • Wide lanes with no islands at 4 crossings - Drivers are conditioned not to stop or look for pedestrians or bicyclists 
  • Poles - Hides the bicyclists
  • Sight lines at intersections - fireworks stands block sight lines for drivers 
  • School Crossing: 
  • No public meetings about road widening project had happened in 18 years (rule now changed to require more public meetings) 
  • Walking to school prohibited by principal after VDOT widened the road 
  • 6 lanes to be crossed in front of the elementary school 
  • 45 minute bus ride originally required for kids living right across the street from their school because of hazardous new road crossings
  • Curb radius - used to have 90 degree angles, in 1980s curb radii widened for trucking industry, making it feel like an on-ramp to the highway
 
Potential Solutions
  • Tighten Curb Radii
  • The larger the radius, the faster the moving vehicle can take the turn. This effects your response time & outcome (exponential risk for pedestrian/bicyclists if hit) 
  • No Turn on Red
  • No Right Turn on Red light-up that shows only when pedestrian detected (via push button or other)
  • LPI (leading pedestrian intervals) - pedestrian gets a head start to establish themselves at the crosswalk 
  • Slip Lanes / Pork Chops / Pedestrian Refuges - have their own issues but maybe opportunities
  • Better definitions & vocabulary needed for treatments at nuanced intersections
  • Education
  • Enforcement
 
 

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