Thursday, September 27, 2007

Why our sidewalks need repair / Pourquoi nous devons réparer nos trottoirs

Shallow asphalt on sidewalk in St NomI noticed how badly our sidewalks need repair as I was walking out of the residence the other day. The asphalt has simply broken away in certain areas. It some ways it was nice because it allowed me to look at what was going on underneath. I was a bit surprised at how shallow the asphalt actually is. There was just rock and dirt underneath.

I had never really thought about the depth of the asphalt on the road and sidewalks.

I uploaded the picture I took that morning to my flikr account along with the other photos I snapped of the gas dig in our neighborhood. I laughed as I was uploading the pictures because my account is full of pictures of dirt, holes, sidewalks and streets - all interesting to me but probably not to the general public!

5 comments:

Zed said...

The easiest way to install FTTH in cities is actually to cut a shallow trench in the asphalt, just deep enough to be able to place the fiber optic cable duct under the asphalt and the seal it up. Unfortunately a lot of cities have building codes that prohibit this.

- Zed

Tad said...

Zed,

Thanks again. This is something that I'm going to examine. Someone explained that I may only have to dig 15 cm deep if I'm on private property (in contrast with 80 cm in public roads). I plan on doing some checking with our town to see exactly what the situation is.

The depth of the dig will probably be less of an issue if we can do it at the same time they redo the roads. However, there's been some talk in the residence lately that we won't be able to reach unanimity to get the roadwork done. In that case I'd have to consider options where I actually pay to do something shallow in the sidewalks.

Stéfan said...

"Someone explained that I may only have to dig 15 cm deep if I'm on private property (in contrast with 80 cm in public roads)."

- the 10-15cm deep / 1cm wide trench is a solution that allow you to lay down a cable at minimal cost and time, the main drawback being that your cable is not protected from public works on the surface : if your cable is at a depth of 10-15cm and the town decides to redo its sidewalks, then your cable is dead. On private properties it's different because you are the one who decide when you redo your asphalt (if you have any), therefore it's all your own problem.

- there's a solution for laying down ducts at a depth of around 40cm instead of 80cm, in a trench of about 10-20cm wide (instead of the usual ~50cm), that's called "micro-trench" or "mini-trench". A norm is being prepared and should be released in 2008. It will make it easier for cities to allow these techniques to be used on their roads and sidewalks.

- of course, synchronizing your project with other roadwork projects is the best solution

You can find a few more details about this matter here (in French) :
- Le point sur... Travaux pour un réseau enfoui
- Le point sur... Les infrastructures d’accueil de réseaux filaires
- Voirie, domaine public et réseaux haut débit (that last one is more focused on municipality actions)

Tad said...

Stéfan,

Thank you for the great information. I started reading through the links tonight and it's very helpful - even the section on municipalities. It could prove very helpful for any future discussions with our mayor.

The micro trench idea sounds very interesting, particularly because the residence is responsible for all the property (sidewalks, roads and public areas). However, no one seems to know exactly what this means in terms of how deep we can dig. Are there rules that we, as a residence, would need to adhere to (in terms of depth and width) given that the property is all private?

I also found the general price information very helpful. To recap:

Conduit/Fourreau = EUR 3-8/m
Trenching/Tranchee = EUR 70-80/m

I assume the trenching would much cheaper if the asphalt was all being redone at the same time.

Thank you again for all the information.

Stéfan said...

"Are there rules that we, as a residence, would need to adhere to (in terms of depth and width) given that the property is all private?"

> I'm not sure. I think you can do what you want when on private property. One issue can be that if one day the residence wants to transfer its roads and sidewalks to the public domain, the fact that networks are not buried at standard depth can become a difficulty for further management and maintenance by the town.

"I assume the trenching would much cheaper if the asphalt was all being redone at the same time. "

> Yes, the 70-80€/m is an average cost when you consider that the asphalt as to be cut and redone specifically for your project. The average cost when there's no asphalt involved in more around 30-40€/m. Note that these costs come from "big" projects, with at least a few kilometers of trenching. I guess the smaller the project, the more expensive the cost per unit is.

Micro-trench is cheaper than classic trench, but as I said before the technique is not normalized yet.