Tuesday, 17 November 2015

Complete Streets

A lot of street planners are really embracing or trying to at least something called a complete street. For example on a four lane undivided road, providing a pair of bike lanes, a pair of driving lanes and a two way centre turn lane. I can't remember whether it is this or bidirectional overtaking lanes that are called suicide lanes. Edmonton is getting into this, and published their guides to a complete street, link here: http://www.edmonton.ca/city_government/documents/RoadsTraffic/Edmonton-Complete-Streets-Guidelines_05062013.pdf

It talks a fair bit about a street as a place and a link. To the Dutch, at least modern Dutch streets, this completely contradicts what is said about a street's functionality in Sustainable Safety. It demands that a road/street must, and I mean must, be a link, or a place, but never both. Some existing streets may really have to be both, but it still recommends this for new streets. By link, I mean a roadway intended for medium to high volumes of traffic to get from A to B relatively quickly. A place is a street where you want to be on that street, like many in Downtown are, or there are destinations directly off the street, without needing to use another access road to get to. This includes both the small mostly local kind of shops on Whyte Ave and the Walmart off Parsons Road.

Note that I use street and road as different types of things. This is not an accident, though there aren't good words to describe when something is both. In Edmonton we use street for north south, and avenues for east and west flows.

Lets think about why trying to combine link and place is problematic.

First, in general if the street itself is a place, then having any more traffic than has to exist that is using the street only because their destination is that street makes it hard to do things like cross the road where you would like to do that, the traffic lights make it hard to get anywhere fast, there is constant risk because of the relatively high speed traffic, and it just makes it unpleasant.

Now lets look at what might happen if a road is simultaneously a street. First, the number of side roads and business accesses and driveways that accompany a road being a place is a big risk, lots of conflict points. Second, the people walking around in high volumes is a bit of an obstruction, and makes it more likely that one of them is going to cross where people do not expect it. You could and should expect crossing whenever and wherever you want to on an access road, but not on a road like Whyte Ave if it were a true link. Also note that if you have a destination on the road itself with no space or money to put in a parkade (parking garage), then that means you either need to go onto one of the side roads to park, or you have to park on the street itself. This creates risk, you have to go slowly if you want to parallel park, making it more likely that you will be rear ended, and the fact that you have 2 tonne metal and plastic objects on the side of the road is something that you can easily crash into, it creates traffic disruption if you want to park, by slowing down traffic, and it means the street has to designate space to things that don't make the road more effective at being a link.

Now looking at why the idea of a complete street has flaws from the beginning, lets see what the city suggests (emphasis on suggest. The city is not looking at things like cycle tracks on Jasper Ave even though that would make it a complete street according to their very own guidelines) to try and make streets complete.

Design speed is the first element I want to discuss. The Dutch have it very clear. In urban areas, access roads have 30 km/h speed limits, distributors have 50 km/h speed limits, arterial roads also have 50 km/h speed limits unless access is very restricted, the traffic is fairly far away from the city centre and the traffic can be safe at a higher speed, in which case 70 km/h is posted. Above this and there cannot be traffic lights or roundabouts. Freeways and expressways have 80-130 km/h limits depending on the area, but in urban areas the size of Edmonton, the Dutch would certainly add a system to reduce the speed limit with electronically displayed variable speed limit signs, which are regulatory.

It also suggests that design speed should equal the posted speed. Funny, why do I see a post 2013 (when the guidelines came out) design plan for a divided 4 lane Parsons road with a design speed of 70 km/h with a posted speed of 60 south of South Edmonton Common? This is a terrible idea. It means that if the street looks as if a higher speed is possible, then everyone is going to be around that speed. The police will have to conduct sting after sting, things that would be possible at the posted speed would not be possible at the higher speed, like roundabouts, it needs more space, valuable space, and millions of dollars more. It means things like traffic lights are designed for the higher speed, needing longer green times, increasing delay for everyone. And what happens when someone gets hit? The higher speed means a much greater chance of serious injury or worse. It also means less capacity, because if you design the speed for higher speeds on a road other than an expressway/freeway, then the capacity will be lower. You need more space between vehicles. City planners often claim it is needed to prevent a mistake of speeding from causing damage, but it does nothing to prevent the speeding in the first place. It encourages the speeding and you should be ashamed traffic engineers who came up with this idea or insist on sticking to it.

The recommended speeds are terrible too. 50 km/h in a commercial local access street? What did I just tell you about higher speeds on a road not able to handle it? And it gives the option (read requirement) to have 50 km/h speeds on a local access road. Oh, a road like the one I live on with children playing, interactions with neighbours, walking across the street wherever you like and the police not able to care less about it, and creating emissions and noise on my street for no good reason other than to give a couple seconds absolute maximum of time? I would much rather live on a street like this: Houten Access road, which is within the 30 km/h zone and nobody would ever consider shortcutting through here. If I was a parent, I would much rather my children play there then on a 50 km/h local road in Edmonton.

On street vehicle parking is for some insane reason suggested on street oriented places, but makes no distinction about whether we are talking about a low speed low volume road where parking on street is a safe thing to do or about arterial roads where this would be a terrible idea.

A bit further on it talks about traffic calming. One wording I don't like is it saying most appropriate on local streets, particularly effective at creating bike boulevards. But this wording is a problem because other streets need traffic calming too, and it suggests that bike boulevard benefit the most from traffic calming. But bike boulevards and local access roads equally benefit. Plenty of people on 84 ave would benefit from traffic calming but only 83 is the one being made into a bike route.

And it says not to be used on arterial roads. For things like pinchpoints that can be true, but a few things I would actually want. A raised median has a significant use on arterial roads. Lets take an example from Heritage Valley if I may. On James Mowatt Trail south of Rutherford Road, there is a minor access road intersecting with James Mowatt Trail. This place is significant for cyclists and pedestrians because it would provide a completely unraveled route away from parallel motor traffic if Bowen Wynd was closed to motor traffic and a central refuge was added, along with a zebra crossing and bicycle crossing. Adding a speed table designed for speeds of 50 km/h would further reduce the impact of cars making it intimidating.

Next element I am looking at are sidewalks, cycle tracks, bus stops, and transit lanes, and on street amenities, but that will have to wait until part two, because this post is very long already. I could go on for hours on it.

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