Transit Versus the Overly-Accessible Freeway

In the run-up to construction of the Green Line between Minneapolis and Saint Paul, neighborhood activists spent a huge amount of effort to get three extra stations included on the route at Hamline Avenue, Victoria Street, and Western Avenue. These extra stations cut the distance between stations in half on that section, from one mile down to half a mile. This put nearly all of the buildings that face the Green Line on University Avenue within a 5-minute walk of the stations.

Getting that change to happen required advocacy work all the way up the chain of command for transit projects in the United States. In early 2010, the Federal Transit Administration changed the rules to de-emphasize a calculation called the Cost-Effectiveness Index (CEI) while adding an option to include livability as a factor. The change didn’t just affect the Green Line, but meant that any other projects around the country could also benefit.

Considering that tremendous battle, it’s amazing to see that on-/off-ramps to surface streets on Twin Cities freeways—the car equivalent to stations on a transit line—are often spaced less than a mile apart. In the map I made above, around 40% of the area’s ramps are spaced one mile apart or less, and the great majority—about 85%—are less than two miles apart.

The shortest distance I found between two full interchanges is in Golden Valley by the headquarters for General Mills. It’s about 0.3 miles along U.S. 169 between Olson Memorial Highway (MN-55) and Shelard Parkway/Betty Crocker Drive.

The ramps at Shelard/Betty Crocker are also very close to the interchange between MN-100 and Interstate 394, though in making the map, I ignored exclusive freeway-to-freeway interchanges, since they don’t provide any access to surface streets.

The longest stretch of closely-spaced ramps appears to be along MN-36 between Cleveland Avenue and Lexington Avenue—five interchanges on a two-mile stretch of highway, each a half-mile apart.

Transit Modes and Characteristics display board from a Robert Street Transitway study open house

Now take a look at this presentation board from the Robert Street Transitway study and the station spacing suggested for each mode. It’s head-scratching to see these ranges and compare them to what we expect when building infrastructure for cars.

For highway bus rapid transit services in particular, the suggestion is to space stations about two miles apart. There isn’t necessarily anything wrong with that, particularly when highway BRT is laid on top of a system that already has closer stop spacing, but it is striking to compare it with a freeway system where most interchanges are much more tightly spaced.

I’m of the opinion that most of the Twin Cities bus network has stops that are packed too close together—usually around 1/8th of a mile apart on local routes, and sometimes even less. This isn’t a huge problem on less-used and less-frequent routes, but busy lines are made interminably slow when they need to stop every block (and sometimes even more often than that!), but buses that run every 10 minutes or less are typically busy enough to need their stops spaced out a bit.

Two main problems arise when transit lines have closely-spaced stops: First, passengers get on and off at stops that are as close as possible to their destinations (good for them, but not always so good for the system). Second, passengers can end up making nonsensically short trips, such as waiting 5 or 10 minutes for a bus that will take them a quarter-mile down the road—a distance that can be walked in 5 minutes.

Limiting the points of access reduces those issues and makes for smoother trips. Yes, it is an inconvenience for some, but it tends to provide benefits to far more riders than it hurts.

Would similar effects be possible by spacing out some of our freeway access points? Can traffic congestion on highways be alleviated by encouraging some of the extremely short trips to happen on surface streets instead?

In urbanized areas with valuable land, this might be a simpler and better alternative to highway tolling, which have historically required toll plazas (difficult to fit into urbanized areas, although they are less necessary today due to RFID and other technologies that don’t require physical payment).

Interstate 94 between downtown Minneapolis and downtown Saint Paul has a fraught history, but it probably has one of the region’s better designs. Ramps are mostly spaced about a mile apart, with additional roadway crossings every half mile and pedestrian bridges in between those. There’s a crossing of some type almost every quarter mile.

Freeways can provide a great improvement in travel speeds, but designers have often been too focused on providing more car access to the freeway than improving the ability for people in all types of traffic to get across freeways or around and between nearby neighborhoods.

Some ramps should be removed, though in most cases the bridges crossing the freeway should be maintained. The bridges could also be reworked to add new freeway BRT stops, like the 46th Street station along Interstate 35W in Minneapolis—rather than removing access, it would change the type of freeway access from automotive to transit. In the long term, that would improve the overall throughput of the freeway system by getting more people into high-capacity vehicles.

Looking the other direction, our region’s current pattern of freeway ramp spacing should provide some lessons to transit planners. Even though the primary mode of transportation on the highway is by car, the spacing varies significantly in response to geography and the surrounding development pattern.

In my mind, it doesn’t make sense to say that commuter rail should only stop once every 7 miles, as shown in that display board—many parts of the world have “commuter” trains that stop about as often as our Blue Line light-rail service. Transit planners should be more adaptive and do what’s right for a particular corridor rather than sticking too close to an often-arbitrary modal definition.

Besides, how can we expect people to switch to using buses and trains more often when it’s harder to reach them than it is to get to the nearest highway? These are some of the questions we need to consider as we work to ensure a stable footing for the future of the region.

About Mike Hicks

Mike Hicks is a computer geek at heart, but has always had interests in transportation and urban planning. A longtime contributor to Wikipedia, he started a blog about trains and other transportation after realizing it had been two decades since he'd first heard about a potential high-speed rail line from Chicago to Minneapolis. Read more at http://hizeph400.blogspot.com/

17 thoughts on “Transit Versus the Overly-Accessible Freeway

  1. Monte Castleman

    Pretty much agree that short trips should be done on local streets, except that urbanists get bent of of shape at the suggestion that streets be designed to facilitate this (say Blake Road, or the hate directed at American Blvd and 77th, two streets explicitely and specifically designed to take short trips off the freeway). A wide suburban style road facilitates short trips as an alternative to a freeway. A two lane street with 10 foot lanes, no turn on red, and a 20 mph speed limit does not.

    1 Mile spacing is now the standard- witness the spacing on the new freeways like 212 and 610; close ramp spacing wasn’t the only sub-optimal thing we’ve gotten away from, left exits I’m looking at you.

    The other thing about fewer interchanges is they need to be more car-friendly to handle the traffic, the SPUI at Lyndale was built not just to address the horrible congestion before, but some of the additional traffic once the Nicollet ramps are removed.

    1. Sean Hayford OlearySean Hayford Oleary

      I think part of the frustration with 77th, Monte, is that — to date — no interchanges have been removed along 494. We’ve basically created a triple-wall between Richfield and Bloomington. First, we have 77th St (complete with 12′ tall barrier that prevents people from walking to businesses in the strip, and divides the apartment buildings from the rest of the community). Then 494, where every bridge within Richfield is also an interchange (save for Xerxes on the western border). Then American Blvd — an overbuilt stroad even worse for pedestrians than 77th.

      I know the long-term plan is to close the ramps at Nicollet and 12th and create a new interchange at Portland. Personally, I’d love to see the Nicollet ramps closed today. Get some Jersey barriers out there and covers the signs. I live right in the area that would be most affected (between Nicollet and Portland), and I do not think having to go slightly west to go east, or go a whole mile on a surface street (to 12th Ave) is such an inconvenience. In fact, it was closed for construction two years ago for a couple months, and it was just fine. I would far rather have 494 and Nicollet be safer and more livable.

      Which is to say, more generally, I agree with your point, Mike. An expensive option, but arguably the best of both worlds, is the sort of separated auxiliary lanes that are used in several places along TH 12 and near Excelsior/36th and 100. This allows pretty much the same level of access without impeding the freeway flow, and takes cars off local streets faster.

      1. Adam FroehligAdam Froehlig

        Long-term, MnDOT would like to close the Nicollet interchange. I’m not sure if they’re waiting for the funds to revamp the Portland interchange or if there’s some local opposition to closing the Nicollet interchange, but one of the two (if not both) is the reason they haven’t done it yet.

      2. John Charles Wilson

        LOL about the “triple wall” between Richfield and Bloomington, though I know you’re right. I occasionally walk between Culver’s and Menard’s and that is a doozy.

        Maybe instead of the unsightly border fence between the US and Mexico, they could have built an east-west freeway with two pedestrian-unfriendly frontage roads along the border. That would keep the Mexicans out, LOL! I can just see it now, hundreds of miles across the desert…. A 77th St./I-494/American Blvd. clone (though since it would be on the south side, it would be Mexican Blvd.)

        Traffic throughput and border protection in one….

    2. Sean Hayford OlearySean Hayford Oleary

      Some other thoughts about specific ramps:

      In Richfield/Minneapolis, Bloomington and Crosstown I wouldn’t miss. Especially given the new, supersized diamond interchange at Cedar & 66th, it seems unnecessary. I’d also be fine losing either Penn or Xerxes at Crosstown. (Xerxes seems better built for the traffic, but I realize keeping Penn means better spacing relative to France.)

      In Bloomington, the excessive ramps to 35W seem to also impact connectivity within that area, much like the 494 ramps do. It seems that both the 90th and 94th St ramps (but especially 94th) could be easily closed.

      In Minneapolis, I’d also really like to see the 35th/36th St ramps closed on 35W, replaced with an interchange at 38th (which I believe is or was the long-term plan at one point). That would both provide better spacing with Lake St and allow those relatively short, unproductive one-ways to be removed.

      1. Monte Castleman

        I think the problem is that simply closing Nicollet would overwhelm the ramps on Portland, to the point that they aren’t already. Doing a spot interchange rebuild isn’t an option because AFAIK they’re still sticking to the 1990s goal of shifting the mainline to the south in that area. A out-of-the box compromise might be to close the entrance ramps only for now, since traffic entering the freeway causes more disruption, and traffic waiting to turn onto the ramps backs up traffic on Nicollet.

        As for 94th, I was going to write a post about remaking the area and touching on the recent pedestrian improvements, but basically I would

        1) “Complete” the 98th street interchange by adding a loop, this was planned as far back as the 1980s, and is referenced in not making the Orange Line stops too permanent due to “proposed interchange reconfiguration”,

        2) Do a 4-3 conversion on 90th, 94th, and Lyndale south of 99th and north of 95th, and add one way frontage roads between 98th and 90th to take care of access to 94th. (As well as rebuilding Clover Center closer to the street and incorporating structured parking for the park and ride. Possibly a SPUI at 90th, although the frontage roads would require an additional signal phase.

        As far as 35th and 36th, Moving the ramps to 38th would be good, except the neighbors went ballastic…

        1. Sean Hayford OlearySean Hayford Oleary

          494: Closing just the entrance would be great for the freeway, but wouldn’t do much to improve the surface-level experience on Nicollet. I drive Portland at rush hour all the time, and things generally flow smoothly. Less than 1 in 10 times, I have to wait through two light cycles to turn left. I don’t recall it being all that bad during the times Nicollet was closed either. Maybe I’ve just gotten lucky, I guess.

          35W: Do we know that 98th is near capacity now? Would losing 94th really cause it to be over capacity? It seems like simply switching the signal to a flashing yellow arrow would allow drivers to take better advantage of gaps. Creating a loop for EB to NB would wipe out half the parking of the transit center, and create problems for vehicles exiting NB 35W. (Wouldn’t the signal get bumped over to Aldrich, making a very tight spacing there?)

          As a related matter, I’d really like to see the geometry of the existing WB to SB ramp reworked so it was more of a traditional right turn at the intersection of “Dupont Ave”, rather than a freeway-style off-ramp that endangers bicyclists and pedestrians. This newer style has been using in many places throughout the south metro — like Burnsville Pkwy and 35W. This seems to have all the traffic benefits of the loop without making a surface street feel like a freeway.

          Pretty much agree with all your other thoughts. re: Bloomington changes. I’d also lose the NB third lane on Lyndale between 98th and 95th. 5 lanes seems like a great plenty.

          1. Monte Castleman

            I live a few blocks from 98th and I-35W, and it gets congested at rush hours. EB 98th to NB I-35W is a heavy movement that only has a single turn lane. If you built the loop you could just get rid of the lane and build a MUP or cycletracks over the bridge. I know it would take out the Park and Ride, hence my plan to relocate that to where the Clover Center and/or Freeway Ford are, along with buildings facing the street. Kind of how I envision it the only nonsignalized ramp pedestrians would cross would be EB 98th to SB I-35W, which already is a free turn.

            The signal on Aldrich would be tight spacing, but that problem could probably be dealt with. I’d also like to make Garfield a left in / right out only (maybe allow right ins during non-peak hours) and remove that signal.

            Agree that an auxiliary NB lane on Lyndale isn’t needed, I don’t even like them as a driver because I still don’t trust left turning traffic not to swerve into them.

            A pedestrian overpass at 102nd would be nice too.

      2. Gabe

        I live near the 35/36th St ramps on 35W. The spacing from Lake is a bit short, but it’s reasonably spaced with the next one to the south, 46th. Curious what the case for a major reconfiguration effort would be given a 2-3 block shift.

        But what always makes me think “Really?…Really!?” is watching a car enter 35W southbound from the Late/31st on-ramp, stay in the short-but-usually-manageable shared entrance/exit lane, and proceed to exit on 35th. It’s not uncommon at all for people in that area to use an *Interstate* highway for what’s effectively a 4-block drive.

    3. Alex CecchiniAlex Cecchini

      I have no problem with people making short trips on local streets by car. Let’s face it, they’re going to be driving on local streets to get to/from the freeway entrance ramp anyway. I just don’t see how speeds below 25 mph aren’t considered “facilitating” this.

      1. Adam MillerAdam Miller

        I also wonder if not going faster than 25 while sitting in traffic on a big, wide street isn’t just as, or more, frustrating and discouraging to short trips as going less than 25 on a street designed for 25 and accommodating other modes.

    4. Matt SteeleMatt Steele

      The missing link in your concern about local streets serving local trips: Trip generation density. With higher trip generation density, trips are shorter and more closely spaced. And VMT in that microeconomy of asphalt is significantly reduced despite meeting the same mobility needs.

      Trip generation density!

  2. Matty LangMatty Lang

    Interesting stuff, Mike. Living in the Midway, I need to cross over I-94 pretty much every day and the 1/4 mile crossings are wonderful especially with crossings like Snelling/Hamline/Lexington/Dale being very unattractive to walk or bike on. Having options relatively close to all of them is a lifesaver, probably in the literal sense too.

    I will note that i-94 in Saint Paul has what amount to auxiliary freeways on either side in Concordia and Saint Anthony Avenues between downtown and Snelling/Prior respectively. These streets are two lane one-way pairs with relatively few stops and no traffic calming that result in a fair share of high speed car trips that would otherwise be on the freeway.

    I bet we could come up with a superior design for local car trips than the Concordia/Saint Anthony pair or the American Boulevard example cited by Monte above. Such streets should not need to emulate the design speeds or capacities of the actual freeways.

    1. Rosa

      what’s the closest pedestrian/bike crossing to Dale? I was working over there this spring, and I kept meaning to ride my bike (to/from the Dale light rail station) and kept getting daunted by the thought of riding on Dale at 11 pm on the way home.

  3. Bill LindekeBill Lindeke

    Such an interesting topic, Mike, and one that I’ve not thought much about before.

    Some of the dynamics involved include the desire for on-ramp proximate land for auto-oriented businesses like office parks, gas stations, car dealerships VS. liveability and reduced high-speed traffic in and around neighborhoods. As a point of transition between high speed freeways and neighborhood streets, on-ramps create the most dangerous urban spaces for pedestrians and/or kids playing in yards etc. They’re hugely detrimental to the surrounding areas! But some business owners and constituencies really want them for economic reasons.

    Are there examples of freeway systems with 2-mile access spacing in urban areas in other countries?

  4. David MarkleDavid Markle

    The cost effectiveness index made good sense, in my opinion–one of the few things about the GW Bush administration era that did–and the change (as promoted by Jim Oberstar) enabled St. Paul and the irresponsible Met Council to have their way: to run the train on the street as a billion-dollar streetcar (but with few stops) rather than along the freeway (probably a less than 5 minute walk from any point on University avenue–or Marshall Ave.– using Hicks’ standard) where it could be reasonably fast as a train should. Thus we end up with an LRT line that’s extremely slow (compared to examples from other cities) AND GETS FEW DRIVERS OFF THE FREEWAY.

  5. Rosa

    I really resent the idea that it’s just “convenience” that’s at stake with the bus stops. If people are waiting 10 minutes for a bus that saves them what you think of as “a ten minute walk” then they’re doing it for a reason, and it’s probably a good one.

    Being able to use the bus as your primary form of transportation means being able to count on being able to use it all the time. That means, even if (like mine has been all spring) your bursitis is acting up and it hurts to walk. Even if you are an unsteady walker, like a lot of elderly and disabled people are. Even if you are hauling heavy groceries and have little kids with you. Even if you have to get your wheelchair down unevenly-shoveled and blocked-by-plowed-snow sidewalks at the other end.

    Most people on foot already have a built-in walk to get to transit, so the 1/8 or 1/4 mile between stops is added on to the distance from the transit line. I’m lucky to be exactly on one bus line, but the other major lines in my neighborhood are already 4-8 blocks apart, so the individual stops being spaced 2 blocks farther would be adding 25-50% more walking – on each end of the trip, for most people. In a world where we expect car drivers to balk at a one-block walk at the end of their driving trip, that’s not at all reasonable.

Comments are closed.