I need help presenting next years pipe replacement program to management

[BenVan_Kesteren1]

Hi Everyone, 

I work in a local government and one of my roles is to help come up with next years water main (and sewer) renewal program. 

I have each of our pipe segments mapped, each with individual asset id, installation year, construction material, diameter etc.

On top of this I have another table (joined by a 1-M relationship) to each and every burst or fault recorded against each pipe segment. And this is what management would like me to weigh in on. They have asked me to present "a list of water mains that based on breakage/fault history should be replaced".

I am wondering if anyone else out there has a similar project they had done in the past, and how did you go about presenting this?

I could simply order my pipes by the greatest number of recorded faults to least amount of faults, but I don't think this would be the most effective method. 

Can anyone else provide any ideas on how they go about collating and presenting this information?

Thanks for your time.

[JoeBorgione]

Haven't actually done an anlalysis like this, but lived it in my neighborhood: over the course of about a year, my street (horse shoe shaped, not a through street) experienced an extreme number of bursts and subsequent emergency repairs.  I think I'm the only one not to have my curb and gutter replaced.  At any rate,  I think the spatial component is what you need to sell:  map out your bursts and see where the hot spots are.  This will be indicative of the condition of your lines.  From there you can examine what the common denomitators are: type of pipe, age, etc.

In my neighborhood I got to be buddies with the crews that came out for the repairs; ice water on a hot day is an easy way to make friends.  At any rate, the guys told me that my street along with a few others nearby were all plumbed back in the late fifties and early sixties by the same contractor who had a reputation of using what ever he had on hand as far as materials go.  For just about as many holes in water lines I've observed, I've seen a different style of pipe, all cobbeled together.  Finally, the city replaced the main.

[BenVan_Kesteren1]

Yeah thanks for that. There is another guy in my team who will be providing his list of pipes he wants repaired based on material+age calculation (no . So mine is purely a spatial question.

So I was thinking to make it 'fair' that I get the total length of the pipe, then divide it by the number of bursts, to get a 'score'. The higher the score the worse off the pipe. Does this make sense?

For example a pipe segment that is only 10m long, may have two bursts, and a pipe that is 1km long may also have two bursts, and I think the shorter pipe should be replaced before the 1km, as it has more bursts per lineal meter.

Does this make sense to others? Or am I over/under complicating it?

Thanks

[JoeBorgione]

The scoring concept is interesting, so no that's not overly complicating things. You know you management better than I; what are they going to be looking for?  There are times the K.I.S principle wins too:  Keep It Simple.

The thing is, you are in the drivers seat here and if you present them with a couple different approaches, my guess is thier reaction is going to be ' Hmmm.  This guy is on to something...'

[MartinPflanz]

Ben,

Pipe scoring is quite a popular topic for water system groups!  I have seen the pipe score most commonly set by a weighted average of: material, age, and breaks.  That weighted average depends on how important each variable is at an organization - an older system may rank age differently then a newer system.  There are some secondary and, al be it, a bit more complicated variables such as criticality (if you lose this pipe how big of a deal is it? who is out of water? is delivery impacted? if so, by how much), pipe embedment type, installer, and also the normal operating pressure (normally high pressure or normally low pressure for that particular pipe).  Hydraulic analysis tools are available help evaluate the hydraulics questions.  Once you have the metrics for each pipe calc'd, consider using Insights for ArcGIS (Water Analytics) to ready the message for management's decisions.

~Martin