9 Barriers to Walking in Sydney

I am a pedestrian in Sydney, living in a car-less household, so I have had a few months experience in the pedestrian environment. As nice as walking in Sydney is, walking in Sydney should be nicer. For a city with such high densities of people and shops, such a large number of parks, doors on the street, and gorgeous weather, and such terrible internet service driving people from their homes, walking should be the dominant mode. Yet there are barriers to living the motor-free lifestyle here (and undoubtedly elsewhere). Some that come to mind.

  1. At Broadway, for instance, the Pedestrian is not allowed to cross on this side of the street, and is instead forced to cross two roads (or maybe three) to cross one. Is this really safer, running the pedestrian through more potential vehicle conflict points.
    At Broadway and City Road, for instance, the Pedestrian is not allowed to cross on this side of the street, and is instead forced to cross two roads (or maybe three) to cross one. Is this really safer, running the pedestrian through more potential vehicle conflict points.

    T-Intersections Intentionally missing crosswalk markings (and pedestrian signals) are quite common, especially at T-intersections, where pedestrians might only have markings and a signal on one side. While this undoubtedly makes cars go faster (the presumed purpose for this), it makes the walker’s life more miserable, reducing choice and potentially adding travel time. For longer distance trips, backtracking can be avoided by crossing upstream where the signal is available. For short distance trips, this is inefficient. The largest T-intersection I have encountered where this is an issue is City Road at Broadway, where to get from the east side of City Road to the north side of Broadway (which houses a nice shopping mall) requires crossing both streets instead of just one.

  2. Fences. Walking midblock is strongly discouraged on some roads. Presumably for safety and for traffic flow, but still creating a chaffingly regulated environment for the pedestrian who wants to cross the shopping street.

    A regulated pedestrian environment (Hume Highway in Ashfield)
    A regulated pedestrian environment (Hume Highway in Ashfield)
  3. Obey
    Obey

    OBEY Pedestrians must obey traffic signals or risk getting run over. While almost all of the Pedestrian Actuation (Beg) Buttons work, the phasing of traffic signals is so chaotic as to be nearly unpredictable as to when the pedestrian has right-of-way without a light. The pedestrian phase is extremely, needlessly short, just enough for pedestrians already at the corner when the light changes to make it across on the green walking man, not enough for someone not there, even when the car phases would make it safe for pedestrians to cross. Drivers only look at traffic lights, not for context, so if you are in the crosswalk (marked or otherwise) you will very much risk getting hit (or at least the ire of the driver) if you do not have a green walking man providing moral and legal support. In many cases these are absurd.

    For instance the figure at Thai Tha Hai restaurant.

    I think I can make it across, even if the standing man is red.
    I think I can make it across, even if the standing man is red.
  4. Uneven sidewalks. For a variety of reasons, most sidewalks appear original, although wheelchair curb-cuts have been retrofitted in most places. While roads are periodically resurfaced, the sidewalks, which were likely fairly even when first poured, have unevened with the heave and ho due to poor construction, changing soil conditions, trees, recent construction and the like. Except for the few sidewalks that have been shaved, this leads to tripping hazards. While these hazards are easily identified (send out some interns), it won’t be solved unless someone develops a multi-million dollar robot to ride all the Sydney sidewalks and provide a report, with a large construction contract on the other end.
  5. Shared paths. Many sidewalks are marked as shared paths with bicycles. This isn’t as much of a problem for the pedestrian as it might seem, since so few people bike. That is a problem for other reasons.
  6. Circuity.
    A commute in Sydney
    A commute in Sydney

    Much of the network is circuitous (see [1],[2],[3]), missing links abound. I previously noted the lack of railway crossings, but there are other issues on the street network. I haven’t tested whether this is especially bad here compared to other places, but subjectively it is noticeable. So for instance my trip from home to work more or less as shown in the image could be much straighter than it is, were there a southern/western crossing of the tracks at Redfern station.

  7. Crowding. While pedestrian crowding is not common on most sections of sidewalk, there are times are places where this is a problem. (In the map, the path to and from Redfern Station gets crowded at peak times). Crowding is a problem for several reasons. Pedestrian speeds are slowed to the speed of the slowest traveler, so overtaking is required. The sidewalks are narrow in place, worse on trash collection days, when the rubbish and recycling bins are out. The crowding is especially a shame given the use of space to store empty cars on streets, space that could be reclaimed for more productive human movement.
  8. Lawson St. and Everleigh St. The navigation sign is correct, and there is nominally a shared zone. Spot the mistake.
    Lawson St. and Everleigh St. The navigation sign is correct, and there is nominally a shared zone. Spot the mistake.

    Navigability. While soon our Augmented Reality glasses may make navigation an irrelevancy, in the meantime, I often try to figure out where I am. This requires looking at my phone because there are not street signs visible to pedestrians. The signs are aimed for autos, and on one-way streets for cars (which are still two-way streets for pedestrians), the signs all face the direction the autos are moving.

  9. Fumes and Noise. Cars and especially trucks and buses produce fumes and noise and other externalities that increase the unpleasantness of walking and lower the pedestrian’s expected lifespan. While electrification will eventually do away with both fumes and noise, trucks will be the last surface vehicles to electrify, so this will likely be a feature on the roads for decades. Given the rate of construction in Sydney, many of these are especially large, loud, and polluting construction-related vehicles.

All of that said, there are plenty of nice parts. Some of the best features of walking in Sydney are below:

  • There are some pedestrian only streets (e.g. Kensington, shown)
  • There is a lot of traffic calming within shopping streets and neighborhoods. (The effect of the traffic calming is to push more traffic to the signalized arterials, where it is controlled, but now more congested than it otherwise would be.)
  • Drivers almost always obey the marked crosswalks if a pedestrian is waiting to cross (though what constitutes ‘waiting to cross’ is a bit ambiguous). (They will not yield at unmarked crosswalks unless the pedestrian is in the street, and even then only reluctantly and with ire.)
A pedestrianized street in Chippendale. Kensington Street.
A pedestrianized street in Chippendale. Kensington Street.
A more supportive pedestrian shopping street in Summer Hill, with a pedestrian crossing table.
A more supportive pedestrian shopping street in Summer Hill, with a pedestrian crossing table.

Why Looking at Crash Stats Alone Doesn’t Tell the Whole Story About Pedestrian Safety | Streetsblog

Stephen Miller at Streetsblog writes Why Looking at Crash Stats Alone Doesn’t Tell the Whole Story About Pedestrian Safety: New research from Minneapolis shows that there is safety in numbers for pedestrians.

This map shows the number of crashes involving pedestrians in relation to the number of people who walk at a given location. Via Murphy, Levinson, and Owen

This map shows the number of crashes involving pedestrians in relation to the number of people who walk at a given location. Via Murphy, Levinson, and Owen

Some intersections are riskier to cross than others, but looking at the number of pedestrian injuries alone doesn’t tell the whole story. A new study from Minneapolis combines crash data with pedestrian counts to deliver a more nuanced picture of traffic dangers for people on foot. Among the findings: There’s safety in numbers for pedestrians.

Using data from the city government, University of Minnesota researcher Brendan Murphy and his co-authors looked at 448 intersections where both pedestrian counts and automobile counts were available, then cross-referenced that data with the city’s crash reports. They found a strong negative correlation between the number of pedestrians and the risk of being hit by a car.

While the study found people are less likely to be struck by a driver at locations where lots of people walk, it does not establish causation, Murphy says. “We don’t have good statistical evidence to show that if a place is safe, people will walk — or in the other direction, that if people are walking, they make the place safer,” he says. “I personally think it’s a bit of both.”

Per person, pedestrian-rich areas downtown and near the University of Minnesota pose a low risk for people walking, though they have a high absolute number of pedestrian crashes. Quieter intersections in more residential neighborhoods also pose a lower risk.

A few streets jump off the map as high-risk areas, like Lake Street, which runs east-west across South Minneapolis, and Penn Avenue in North Minneapolis. Both are used by a steady if not enormous number of pedestrians, but are meant first and foremost to move lots of cars. “We can ask, ‘How are those roads designed?’” Murphy says. “They are two lanes each way, no shoulder or bike lane.”

The study looked at all crashes involving pedestrians, not just injuries and fatalities, in order to include enough data points to reach reliable conclusions. It also looked at the stats from 2000 to 2013 in aggregate, rather than year-by-year, so it doesn’t take into account intersection redesigns or major changes like the opening of a light rail line. If there were enough data, Murphy says, “it would be really nice to do a year-by-year analysis.”

The study did not consider the relationship between pedestrian risk and income or race, but the authors say that needs attention. “Equity is a very big problem in terms of pedestrian safety and poor and minority people are getting killed by cars at much higher rates,” Murphy said.

The authors hope their research will lead to better measurements of pedestrian safety and methods to improve it. In 2016, the U.S. Department of Transportation’s four-year strategic plan set a goal of reducing fatalities for pedestrians and cyclists to 0.15 per 100 million vehicle miles traveled by 2016. But that’s the wrong way to look at the problem.

“If we frame pedestrian deaths in terms of VMT, we’re really framing it in terms of automobiles themselves and car traffic,” said Murphy. “We should be focused on reducing pedestrian deaths as a percentage of the pedestrian population.”

There’s also a need for better data collection. Cities and states regularly collect standardized data on car and truck traffic, but there’s no standard for non-motorized users. This data is often collected manually and its reliability varies from city to city. In Minneapolis, three counts throughout the day at each intersection were added together to create a six-hour total. Other cities have different methods.

“Ideally we would like to have our cities wired up and know how many pedestrians are crossing each intersection,” Murphy says. “We need to focus in on the pedestrian population and really ask ourselves, where are they really experiencing undue burdens of risk and what can we do about it?”

Evaluating the Safety In Numbers effect for pedestrians at urban intersections

Recently published:

Average annual 6-hour pedestrian count by location, Minneapolis
Average annual 6-hour pedestrian count by location, Minneapolis

Highlights

  • Collision risk at 448 intersections in the city of Minneapolis, MN was assessed.
  • The Safety In Numbers phenomenon was observed for both pedestrians and cars.
  • Maps of per-pedestrian crash rates inform discussion of safe vs. unsafe city areas.

Abstract

Assessment of collision risk between pedestrians and automobiles offers a powerful and informative tool in urban planning applications, and can be leveraged to inform proper placement of improvements and treatment projects to improve pedestrian safety. Such assessment can be performed using existing datasets of crashes, pedestrian counts, and automobile traffic flows to identify intersections or corridors characterized by elevated collision risks to pedestrians. The Safety In Numbers phenomenon, which refers to the observable effect that pedestrian safety is positively correlated with increased pedestrian traffic in a given area (i.e. that the individual per-pedestrian risk of a collision decreases with additional pedestrians), is a readily observed phenomenon that has been studied previously, though its directional causality is not yet known. A sample of 488 intersections in Minneapolis were analyzed, and statistically-significant log-linear relationships between pedestrian traffic flows and the per-pedestrian crash risk were found, indicating the Safety In Numbers effect. Potential planning applications of this analysis framework towards improving pedestrian safety in urban environments are discussed.

Keywords

  • Pedestrians;
  • Safety;
  • Collisions;
  • Urban planning

Mode Shares 2001 vs. 2011 | The End of Traffic and the Future of Transport

Other mobility options in cities have become more available, attractive, and increasingly used. While the rise of car sharing, ride-sourcing, bike sharing, etc. are generally still too small to measure, walking, biking, and even transit are holding their own or growing compared to the automobile.  Transit use is up nationally due to the large investments in rail lines, that 20 percent increase in transit use in the decade (amounting to about 1 percent of all travel) is far less the 10 percent drop in per capita passenger travel by motor vehicles (about 8 percent of all travel). Recapitalizing transit has had marginal effects. Rather, the decline in per capita auto use is a death of a thousand cuts rather than one clear perpetrator. Walking, biking, school bus, and telecommuting are also all up. Some of that is due to changing preferences, some to the economy as discussed in earlier sections.  School buses are likely due to changes in schools (which are bigger and farther apart) and increased movement away from the neighborhood school. Illustrative data for the Twin Cities is shown in the FIgure. From Levinson and Krizek (2015) The End of Traffic and the Future of Transport. http://davidlevinson.org/the-end-of-traffic-and-the-future-of-transport/  Figure 3.9 Source: Schoner, Jessica, Greg Lindsey, and David Levinson (2015) Travel Behavior Over Time. MnDOT Report.
Other mobility options in cities have become more available, attractive, and increasingly used. While the rise of car sharing, ride-sourcing, bike sharing, etc. are generally still too small to measure, walking, biking, and even transit are holding their own or growing compared to the automobile.
Transit use is up nationally due to the large investments in rail lines, that 20 percent increase in transit use in the decade (amounting to about 1 percent of all travel) is far less the 10 percent drop in per capita passenger travel by motor vehicles (about 8 percent of all travel). Recapitalizing transit has had marginal effects. Rather, the decline in per capita auto use is a death of a thousand cuts rather than one clear perpetrator.
Walking, biking, school bus, and telecommuting are also all up. Some of that is due to changing preferences, some to the economy as discussed in earlier sections. School buses are likely due to changes in schools (which are bigger and farther apart) and increased movement away from the neighborhood school. Illustrative data for the Twin Cities is shown in the FIgure.
From Levinson and Krizek (2015) The End of Traffic and the Future of Transport
Figure 3.9 Source: Schoner, Jessica, Greg Lindsey, and David Levinson (2015) Travel Behavior Over Time. MnDOT Report.

Accessibility and Centrality Based Estimation of Urban Pedestrian Activity

Recent working paper

Estimated evening peak period pedestrian activity
Estimated evening peak period pedestrian activity

Non-motorized transportation, particularly including walking and bicycling, are increasingly becoming important modes in modern cities, for reasons including individual and societal wellness, avoiding negative environmental impacts of other modes, and resource availability. Institutions governing development and management of urban areas are increasingly keen to include walking and bicycling in urban planning and engineering; however, proper placement of improvements and treatments depends on the availability of good usage data. This study attempts to predict pedestrian activity at 1123 intersections in the Midwestern, US city of Minneapolis, Minnesota, using scalable and transferable predictive variables such as economic accessibility by sector, betweenness network centrality, and automobile traffic levels. Accessibility to jobs by walking and transit, automobile traffic, and accessibility to certain economic job categories (Education, Finance) were found to be significant predictors of increased pedestrian traffic, while accessibility to other economic job categories (Management, Utilities) were found to be significant predictors of decreased pedestrian traffic. Betweenness centrality was not found to be a significant predictor of pedestrian traffic, however the specific calculation methodology can be further tailored to reflect real-world pedestrian use-cases in urban areas. Accessibility-based analysis may provide city planners and engineers with an additional tool to predict pedestrian and bicycle traffic where counts may be difficult to obtain, or otherwise unavailable.

Begging for Simplicity

Cross-posted from streets.mn: Begging for Simplicity … in which I complain about beg buttons, and general second class treatment for pedestrians.

Begging for Simplicity

 

Pedestrian actuators call for a pedestrian signal at an intersection which is semi-actuated (where the green-time goes to the mainline except when a vehicle is on the side street, subject to a maximum cycle length and a minimum green time for the side street) or fully-actuated (where the green time is allocated to approaches which are actuated subject to a lot of constraints). When they do this, they also tell the controller to extend the green time (and parallel walk signal) given to a phase to be sufficiently long to allow pedestrians to safely cross.

Replacement Walk Button (Franklin and Seymour)

Decommissioned Walk Button (Franklin and Seymour)

But this has problems. Imagine you are on a side street about to cross a main street and the light turns green for the cars, but the Don’t Walk sign remains (since no Pedestrian actuation was recorded). You did not get to the actuator quickly enough. Should you cross on the Green but against the Don’t Walk, or should you wait almost an entire cycle for this to come around. You may or may not have enough time to make it across.

Second imagine the actuator is broken. It may never give a walk signal. (There aresolutions for that, where the default state of broken is “on” instead of “off”, but that doesn’t seem to be widely deployed). For instance, recently I reported toSeeClickFix a broken pedestrian actuator at Franklin and Seymour Avenue in Southeast Minneapolis, which was corrected within 18 days (i.e. the case was closed within 18 days). I am fairly confident a broken traffic light serving cars would have been corrected sooner.

The next  two “beg buttons” (pedestrian actuators for traffic signals) were recently photographed. The one on the University of Minnesota campus (at Beacon and Harvard) recently had a time exemption added, implying that the actuator need not be pressed between 8 am and 6 pm weekdays. (This time exemption seems to have been removed since the photo was taken). This is an improvement over the previous situation (pushing the button in the middle of the day). Still one expects this will, like so many others, become a placebo button, or just break and make it so there is no pedestrian phase.

Beg button at Harvard and Beacon, University of Minnesota campus

However, the complexity is still needless. Traffic signals on streets with sidewalks (which implies pedestrian traffic either exists or is desired) should ALWAYS have an automatic walk phase, just as every cycle gives green time to cars from every approach. (This is especially true in pedestrian areas like a college campus which has a plan that aims to prioritize walking.) Actuators are fine if they make the walk signal come sooner, but being unpushed should not be used as an excuse not to have a walk phase at all. Car drivers don’t have to go out of their way to press actuators, why should pedestrians?

(If traffic is so low you are concerned the time devoted to a pedestrian phase (~12 seconds (36 ft at 3 fps)?) is too long (will cause too much vehicle delay) for this two lane roadway, maybe it shouldn’t be a signal but instead a stop sign (which requires no pedestrian signal) or a yield sign. This can be implemented with flashing red lights if you must you electrical gear.)

Beg button at Franklin Avenue, East River Road, and 27th Avenue SE

Fortunately it is not as complex as the last, at Minneapolis’s favorite five-way intersection (Franklin Avenue, East River Road and 27th Ave SE), which gives instructions for something that should be tacit. That it is not tacit indicates it is a flawed design. If I can read the instructions, I already know how to cross a street. It is not like pedestrian actuators are a new technology. While I want more information at bus stops, crossing a street should be straight-forward, and not require an 11 line instruction set with five graphics. Sadly there is more information here than at the nearest bus stop.

Update. I found the tweet below, which seems appropriate.

Erik Griswold (@erik_griswold) 11/16/13, 18:13 "Making pedestrians press. buttons to cross streets is the death of the city" -Eric Fischer (@enf) at #transpowest

Open Streets – Minnehaha, and some further comments on the Blue Line and environs | streets.mn

Cross-posted at streets.mn Open Streets – Minnehaha, and some further comments on the Blue Line and environs

Open Streets – Minnehaha, and some further comments on the Blue Line and environs

 

I went with my family to attend Longfellow neighborhood’s Open Streets on Minnehaha on Sunday August 11, 2013. I hadn’t been to an “Open Streets” before, though I had been to various events where streets were closed, and this was like that, but more spacious and far more bikey.

OpenStreetsLongfellow

We drove to near the northern entrance, since we don’t really live within walking distance (certainly not for the 3 year old). We entered on the north side, at Lake Street and walked down to 46th Street. From there, we walked along 46th over to the LRT station, which we took back to Lake Street station, whence we returned to the Open Streets festival and onto the car to return home.

Closing streets like this once a year is a great thing. Maybe we should go all in and close all streets in Minneapolis one Sunday just to see what happens. Obviously you cannot get the concentration of people on any street, but it would be an interesting experiment.

This one is clearly driven by the bike folks. The various Bicycle Liberation Fronts were all active. Also ran into a bunch of people I knew, so a disproportionately large percentage of attendees were either transportation professionals or advocates. Also we had an almost impromptu Board Meeting of Streets.MN, but could not quite gather a quorum.

There was a nice demo of the proposed CycleTrack on Minnehaha (And why is this even an issue? Make it a demonstration project and study it to see if it works as well as bike lanes on either side according to various criteria.)

My sense is that the activities were too diffuse for pedestrians. At the speed of bicycles, the distances were appropriate (and I saw lots of bicyclists riding back and forth a couple of times, but the 2.5 miles over which this stretched there was a lot of “dead space” for a street festival.

Why were there so many police? Was someone expecting trouble? This seemed far more than necessary for traffic control. Maybe some were expecting a street fight between the many Mayoral candidates and their tee-shirted hordes?

Also, as my wife bemoaned “where are the food trucks?” I would have expected more for this crowd of people. I know the local restaurants (and the American Legion – which offered an excellent value for drinks and hot dogs) didn’t want or need the competition, but the art festivals had food trucks. Was there some prohibition, were they not invited, or did they just not want to come?

The kids did enjoy the bouncy house and the inexhaustible on-street tap-dancers, as well as some of the musicians and the skateboard demonstrations.

Also there seem to be a lot of yoga studios, massage, acupuncture and alternative medicine places here. I am not sure what it says about Longfellow, but it is a lot like 1970s Northern California in that regard.

So as we reached the end of the trip near 46th, we chose to take the LRT back rather than retrace our steps.

My god, the pedestrian streetscape at the LRT stations is abysmal. And I don’t just mean the lack of integrated street-fronting land use, I mean simple things, like pedestrian crossing signals.

At 46th Street and Hiawatha, we pressed the actuator. While the traffic light turned green, the walk signal did not. This occurred even though we had a protected movement. So I crossed against the pedestrian light, but with the green light, otherwise I would be stuck on the East side of Hiawatha Avenue for a long time. I don’t know what the standard signal pattern is here, and maybe it was screwed up by the LRT vehicle coming from the north forcing the gates down sooner than the engineers thought that pedestrians would be able to completely cross, but it seems it was optimized for cars and against pedestrians.

I had never stopped at this (46th Street) station before. Why are the benches in the areas that are unheated/unshaded, while the heated/shaded area is standing room only? Seems needlessly hostile to patrons, and is unlike at least some of the other stations. Also, why do the electronic message boards not know when the next train will arrive? This is 20 year old technology, developed well before this line was built. Still, far better than typical Minnesota bus stops.

At Lake Street station we exited. I had never had cause to walk around here either. This is worse than the area around 46th.

There is an up, but no down escalator. OK, I have seen this at stations before, it saves money, and my home station Franklin Avenue has no escalator at all. When you exit, and want to go east, first you have to cross freeway exit ramps. Technically Hiawatha Avenue is not a Freeway, and Lake Street is supposed to be an urban street, so I am unclear why this is a SPUI. More importantly, why do I get a pedestrian signal on one ramp, (the west-bound ramp from Hiawatha to Lake) but the other is catch as catch can with a “yield” sign for vehicles exiting Hiawatha going east onto Lake Street? They should at least have a stop sign or signal, given this is an urban environment with a transit stop.

(To be clear, this has all been noted before, see e.g. the Comments on Sam’s post. I have suggested studying grade separation before, and I still think the current situation is just a compromised and dangerous mess.)

At any rate, we did eventually all make it across alive, and walked along an unpleasant-ish segment of Lake back to the festive Open Streets area in front of Gandhi Mahal. There we partook of liquid refreshments and made our exit.

How shoveling and plowing snow now extends the duration of icy sidewalks

Cartoon

Minnesota is getting still more ice/sleet/freezing rain/snow today. We will see piles of snow for a long time. Why will we see piles of snow? Because we piled it up. The snow on top acts as insulation for the snow below.
Imagine there is a winter where we get 1 meter of snow (in fact the average for Minneapolis is 1.26 m of snowfall). On the 1 m wide boulevard between the 1 m wide sidewalk and the street, we get 1.5 meters high of snow, as we transport half the snow from the sidewalk to the boulevard to “clear the sidewalk” (the other half goes into the yard maybe, if we have yards. If we have buildings, it all goes to the boulevard). (I realize this is not all at one time, which complicates the model but does not change the basic point).
If the snow melts and sublimates at 5 cm/day (this varies), (and water (liquid snow) refreezes at night), instead of 20 mornings of icy sidewalks, we have 40 hazardous mornings. We have approximately doubled the problem.
This problem in embiggened when you add the snow plows piling additional snow onto the boulevard. In this case we take a 10 m wide street and pile 5 m x 1 m of snow on the boulevard on each side. Now we have put not just 0.5 m from the sidewalk but an additional 5 m of snow on each Boulevard. So the Boulevard is responsible for storing 5.5 m of snowfall over the course of the winter. The ground absorbs very little since it is frozen.
Fortunately, cars are local urban heat islands, so the road is warmer than the sidewalk, and the snow melts back towards the roads at a faster rate than on the sidewalk. Unfortunately, sidewalks are interrupted by streets, which are now icy and slushy in the gutter in the morning. Similarly, we are fortunate that buildings are urban heat islands. Unfortunately, new buildings are well-insulated, greedily keeping their warmth rather than sharing it with the adjacent sidewalks.
For the purposes of walking, I wonder whether it might be better to not shovel or plow at all, and take the inconvenience of walking (driving) through snow, than to shovel and increase the duration over which we must traverse ice and slush. This might be a case of getting punished for doing the “right thing.”
An alternatives is to actually move the snow off the sidewalk’s upstream water-basin. In large cities, we might take the snow piles and put them to the side away from the walk path. This answers the questions: Surface parking lots, what are they good for?
Cartoon from AMAZING FACTS…AND BEYOND! WITH LEON BEYOND

Sidewalks are Hotting Up

Brendon writes in:

Heating a sidewalk section has climate change implications. I calculate the 26-year cost of your section at $8,722 at the low end and $9,708 at the high end (depending on the discount rate you assign to the future impacts of climate change. I tend to lean towards the higher end). This means your break-even point is 8% to 20% higher, meaning maybe 173 to 192 pedestrians per day. Of course with a carbon tax in place, there would likely be more walkers in some places, meaning heating the sidewalks become feasible in more places.
Now, if you could use waste heat that hasn’t been previously captured to heat sidewalks, as they are proposing to do with the new “interchange” plaza and HERC steam, the carbon footprint becomes effectively zero additional. Much less per kWh/BTU.
Other interesting facts, heating all the sidewalks in Minneapolis with electricity from the grid for one year would produce more greenhouse gases than the disposal of all our solid waste and wastewater does over the same time period. The additional energy consumption would be equal to about 1/3 of the current annual consumption in all residential properties in the city. It would increase the city’s annual electricity consumption by 8%.

He nicely identifies a feedback effect, heating up sidewalks will create more emissions, which will heat the atmosphere, which will eventually negate the need for heating up sidewalks. There must be an equilibrium point here.
More seriously, the use of waste heat is a great idea, especially near the HERC. The problem would be building infrastructure to distribute that more broadly. There might also be waste heat from wastewater (which is still liquid in the winter, and thus warmer than the ground around it) which we don’t capture, or let go to roads, by running sewers under the streets rather than the sidewalks.