Your BRT questions, our BRT answers
Between our Aug. 17th roundtable, our Aug. 18th webinar, and several e-mails and phone calls, we've received may good questions about Bus Rapid Transit: Chicago's New Route to Opportunity, our vision for a 10-route Bus Rapid Transit (BRT) network in Chicago that is feasible, best supports existing neighborhood assets, and fills accessibility gaps in the current transit network. Here's an assortment of them, with our answers, in no particular order. Annie Weinstock, US BRT program director at ITDP, contributed to these answers.
Q: Given that trips to work represents 60% of all transit trips, why did you weigh all trip generators equally?
A: While we did have only one criterion that was specifically about employment, we also felt confident that work trips were being captured in a variety of other ways. Work trips are an implicit part of most of the trip generation criteria. All trip generators have a work-trip and non-work trip distribution. Retail stores have a small number of work trips compared to a large number of non-work trips. Medical centers have a lot of work trips (doctors, nurses, technicians, and staff) and a lot of non-work trips (patients and visitors). The same applies to the food stores, entertainment, education, and community services. Outside the trip generation criteria, existing travel time and existing ridership are measured during the morning peak period when people are going to work meaning routes with more riders and/or more work trip congestion are receiving a higher score. That said, if we were to use these criteria again to prioritize some other investment – say, where the city should prioritize construction of its new protected bike lanes – we could easily weigh work trips, or any other criterion, more or less heavily.
Q: Is there any specific technology linked with transponders equipped on buses to have traffic signal priority, what is the cost compared to total investment?
A: There is some necessary technology investment for transit signal priority. The cost ranges from $8,000 to $35,000 per intersection (see here for more information). There are federal grant programs which can pay for TSP in certain cases. The important point, however, is that the time savings to buses at intersections with TSP is somewhat insignificant as TSP only extends a green light by a few seconds and only when the light is already green and about to change. This does not happen frequently and TSP does not change a traffic signal from red to green as is commonly believed. Therefore, TSP can be somewhat cost-ineffective. Much more important to prioritizing buses through intersections, particularly when buses operate in the central verge (as they do in the MPC proposal), is the restriction of left turns to mixed traffic across the intersection, or even underpasses (more costly) which circumvent traffic signals and traffic conflicts altogether.
Q: Is the 97' row requirement based on buses with left side doors? What would it be for right side boarding?
A: The 97’ ROW requirement is based on Complete Streets standards and TRCP Report 90 Bus Rapid Transit Volume 2: Implementation Guidelines, which provides minimum standards for BRT lanes and BRT stations. The breakdown is as follows: 1 foot frontage zone (x2) + 5 foot sidewalk (x2) + 3 foot parkway (x2) + 10 foot travel lane (x2) + 8 foot parking lane (x2) + 5 foot bike lane (x2) + 11 foot BRT lane (x2) + 11 foot BRT station (x1) = 97 feet. If you are asking if the envelope would be smaller if riders were boarding along the sidewalk side instead of the median, then the answer is yes. The station envelope could be included within the parkway and the parking lane. We didn’t consider side stations for several reasons. First and foremost, a BRT lane running on the outside of a parking lane would require automobiles to cross through the BRT lane to get to the parking lane. That creates serious safety issues and would adversely impact the speed of the BRT bus. Second, if you want to keep people out of the BRT lane, the easiest way is to create some sort of physical separation. You can’t do that if the lane is in between the travel lane and the parking lane. Third, we preferred to reduce possible conflicts or complications resulting from the City of Chicago's parking meter lease. Fourth, you create conflicts with right turns when you have the BRT lane on the inside of the travel lane. Since, left turns are already controlled, you avoid these conflicts.
Q: Is dedicated lane a must?
A: A dedicated lane is extremely important to reducing or eliminating conflicts with mixed traffic which costs time to buses and passengers. Often, where streets are narrowest or where congestion is the worst, is where a dedicated bus lane is most needed. Where streets are very narrow, there are several possibilities: 1) You can construct a one-way bus lane in order to reduce width requirements and construct a one-way bus lane in the opposite direction on a parallel street; 2) You can convert the entire street to one-way in order to eliminate a travel lane, and then add a one-way bus lane; 3) You can eliminate a lane of parking if it exists; 4) You can convert the entire street into a bus-only street as has been done in many downtown areas with narrow streets. All of these solutions are political, rather than technical and it takes political will in order to make them happen.
Q: Overall why pursue 'gold standard'? an appeal of BRT attributes is that they can be assembled to match the services to demand and to allow buses to operate both on and off the reserved BRT lanes. So why is it appropriate to purse the 'gold standard'?
A: The system that scores BRTs as either gold, silver, bronze, or "not BRT" accounts for on- and off-corridor services and, in fact, gives extra points to systems that match demand in the way you described. That said, in the higher demand corridors where infrastructure is necessary is where many of the other elements of gold-standard become necessary. For more information, please see the BRT Standard scoring system. The system is currently being vetted by international experts and will be somewhat refined but this is the general idea.
Q: In cities that have implemented BRT were there any conflicts with cyclists travelling on designated roadways and if so, what was the nature of the conflict, how was it resolved?
A: There are several ways of designing BRT and bicycle lanes in the same corridor so as to minimize conflict. BRT actually offers the opportunity to reorganize a street so that cyclists can travel more safely than under previous conditions when buses were weaving into and out of traffic to make stops. In Paris, the bus lanes are shared with bicycles since the bus lanes experience lower traffic volumes than mixed traffic lanes and bus drivers are trained to drive safely with bicycles. In cases where there is slightly more road width, it is possible to construct bike lanes adjacent to the central verge bus lanes (on the outside, toward the curb) so that the only conflicts for bicyclists are at intersections. And if the city reduces the number of left turns (for mixed traffic) at intersections in order to benefit buses, bicycles benefit as well. Though it is often done, it is less desirable to construct bike lanes along the curb when bus lanes are in the central verge since then there are right- and left-turning conflicts that may need to be addressed. See this presentation for more details.
Q: The study used a 3-mile minimum when considering possible BRT routes. Is there any reason to consider a maximum length?
A: The length of the route will depend on whether some benefit (e.g., ridership, connections to transit or other destinations, etc.) is delivered by extending the route to the next possible street segment, or whether the next segment is wide enough to even allow for the BRT to travel through it. In our study, most of the routes end at 95th St., largely because the streets aren't consistently wide enough beyond that point. Local buses would certainly continue past that point. However, we opted not to use a specific maximum length (i.e., 12 miles) because of our focus on benefits. It's a fair question then as to why we used a minimum length. There are many street segments that are wide enough for true BRT, and are proximate to quality of life amenities... but in many cases it's just a few blocks. In order to prioritize further analysis and investment, we deemed it necessary to screen those short pieces out.
Q: (there were several questions of this kind) One of Chicago's transit weaknesses is the ability to move east-west at the northern and southern ends of the city. Given that, why doesn't the proposed Irving Park route connect to the Red Line, and why doesn't the proposed Garfield Blvd. route connect to either Midway or the Museum of Science and Industry?
A: Inconsistently sufficient street width, plain and simple. Our focus was on where we could feasibly build true BRT, which requires dedicated lanes, and thus pretty wide streets. Irving Park Road gets a lot narrower east of Ashland as it approaches the Red Line, while Garfield gets too narrow west of Western and east of Cottage Grove. That's not to say a permutation of BRT couldn't work there. In theory the BRT vehicle could reach the end of the dedicated lane and then travel in mixed traffic to these key destinations, that's an 'open' BRT, and it's certainly an option on the table.
Another option, of course, would be widening the streets to allow for true BRT. While a long-term option, this would require a lot of land acquisition, and would be costly and time-consuming. Again, our goal was to develop a vision for BRT priorities in the near term. Would it help reduce congestion if we were to widen a street like Garfield all the way to the lake, connect it with Lake Shore Drive, and then run true BRT along it? Maybe. But could that be accomplished in the next decade? Probably not.
Q: How does this BRT vision differ from the much-maligned experience of limiting State Street to bus and pedestrian traffic?
A: Our vision for BRT accomodates all modes in a single street — walking, biking, driving, and transit — so that it can be used by anyone and everyone. That preserves, and hopefully even builds, the range of activities and users, which is exactly what didn't happen with the State Street Mall.
Q: Due to budget constraints, the CTA had to cut express bus service. How would BRT be different?
A: One of the exciting things about BRT is that, done right, it can help boost property values and adjacent economic activity. Having real stations with recognizable branding is a big departure from the express buses. This also means that as we look to paying for capital investments and operations, suddenly various forms of value capture come into play. Special service areas, special assessment districts, tax-increment financing, and other forms of value capture could complement more traditional financing and allow for a more sustainable stream of funding. All of those options should be on the table, and should be scrutinized thoroughly to ensure that Chicago gets what it needs — better transit and revitalized neighborhoods — in the best way possible.