Bridges built by Developers

[jester86403]

I was wondering if anyone had any knowledge or estimate of how many bridges are built by developers and the like, compared to public departments like the department of transportation?

 

[civilperson]

Even developers' bridges are usually owned and maintained by a government body. AASHTO standards and DOT reviews are the norm. In Tucson, the developer of Rita Ranch paid the Arizona DOT to build the exit and grade separation of I-10. The three major box culverts in the interior became city property along with the ROW after completion.

 

[jester86403]

In a case like that does the developer choose the engineer? If not is it left up to the department of transportation? I guess my real question is des the DOT always pick the engineer?

 

[gwynn]

It may depend on where you are, but generally whoever is paying for the project decides who they hire. Who hires the engineer depends on the contractual arrangements. It may be the owner or the engineer may be a sub-contractor to an architect etc.

 

[Dinosaur]

No, in my area the developer can pick the engineer, but he has to do it to DOT requirements or the DOT will not accept the bridge into their inventory and maintain it. The are a number of developers that do this. We usually get three to five of these a year statewide.

 

[jester86403]

Thats good because I have been looking at different DOT's consultant prequalifcation requirements and with what they require you need like 5 full-time people to do even the smallest of jobs. How can anybpdy break into a field like that. That means you would have to shell out 10000-20000 dollars a month in payroll not knowing if you are going to get any work at all. That seems ridiculous.

Dinosaur,
What are the typical size of those 3-5 per year? What are the typical construction cost estimates? That is if you don't mind me asking?

 

[civilperson]

Fee is 4.5% of construction cost at 60/sq ft, (substructure extra and varies). Another 4% for field supervision, inspection, staking and contract management. Personnel limits can include principals, secretary, engineer, designer, draftsman, etc. Joint venture with materials lab or survey firm will also fulfill the numerical requirements on staff size.

 

[Dinosaur]

Typically the structures are single span over a modest stream near the entrance to the parcel(s). The bridges have a concrete deck 8 or more inches in thickness supported on steel or P/S concrete stringers. The cost is probably over $120/sq ft. The bridges are typically 30 ft face-to-face of curbs. Good luck.