View Full Version : How much does it cost to build a bridge?


Michigan CG
02-03-2010, 07:08 PM
I am appraising 8 acres of vacant land in BFE.

I have one comparable that is in the same township that sold less than a month ago which is 9 acres. I have to use it.

The problem with the comp is that you have to build a 20 foot bridge over a drain to access the land.

So, driving down the road I see a newer house with a bridge. I stop and interview that owner and he built his own bridge with a cost of materials and equipment rental at $28,000; he did the labor himself.

BUT, his bridge is an overimprovement and can carry 100,000 lbs.

I think I am going to check for building permits for bridges but I would guess those would be few and far between.

I simple little land appraisal takes a turn. :angry:

CANative
02-03-2010, 07:10 PM
$28k seems pretty cheap.

If there isn't a lot of government red tape you might be able to throw an old flatcar over the creek and call it a day. You can't get away with that now days in my area. The engineering alone would likely cost more than $20k.

WGrafer
02-03-2010, 07:15 PM
Check Marshall & Swift -- I do recall getting costs for pre-cast bridges in one of their sections, but I'm pretty sure they cost other types as well.

John LaBelle
02-03-2010, 08:01 PM
Check Marshall & Swift -- I do recall getting costs for pre-cast bridges in one of their sections, but I'm pretty sure they cost other types as well.

Just checked my M&S Costbook and there bridges under the Golf Courses in the Segregated Costs Section (pedestrian/golf cart/car or light truck).

Walter Kirk
02-03-2010, 08:16 PM
I saw a property with a bridge made out of an old moble home frame. The owner tore the house apart and drove the frame over the drainage ditch, he then built a deck of pressure treated 2x6 lumber.

Mountain Man
02-03-2010, 08:42 PM
Oh, I thought this was a rhetorical question. Ya' know, with an answer like: How much do you have to give to a Congressman to get a special amendment for a chunk of the Shovels Ready Stimulus money? :)

Calvin the Airedale
02-03-2010, 08:48 PM
I am appraising 8 acres of vacant land in BFE.

I have one comparable that is in the same township that sold less than a month ago which is 9 acres. I have to use it.

The problem with the comp is that you have to build a 20 foot bridge over a drain to access the land.

So, driving down the road I see a newer house with a bridge. I stop and interview that owner and he built his own bridge with a cost of materials and equipment rental at $28,000; he did the labor himself.

BUT, his bridge is an overimprovement and can carry 100,000 lbs.

I think I am going to check for building permits for bridges but I would guess those would be few and far between.

I simple little land appraisal takes a turn. :angry:

Check with the county engineer. He'll have a good handle on costs and will likely have to inspect for approval any bridges which traverse public drainage.

Couch Potato
02-03-2010, 09:20 PM
I am appraising 8 acres of vacant land in BFE.

I have one comparable that is in the same township that sold less than a month ago which is 9 acres. I have to use it.

The problem with the comp is that you have to build a 20 foot bridge over a drain to access the land.

So, driving down the road I see a newer house with a bridge. I stop and interview that owner and he built his own bridge with a cost of materials and equipment rental at $28,000; he did the labor himself.

BUT, his bridge is an overimprovement and can carry 100,000 lbs.

I think I am going to check for building permits for bridges but I would guess those would be few and far between.

I simple little land appraisal takes a turn. :angry:Check for permits on that neighbor's bridge while your at it.

When I needed I bridge, I used an EXCEL bridge (http://www.excelbridge.com/owners/cost.asp). You can contact them for a quote to put in your files, but I would say $20,000 is a reasonable estimate for a 20 ft. bridge with no complications. That's about $8,000 to have a contractor prepare each side with a proper foundation and install the prefabricated bridge which can be bought for about $12,000. Since you describe it as going over a "drain" I doubt any environmental issues would cause a higher cost, but check with the local building department.

nauthead
02-04-2010, 06:28 AM
My sister has a similar sized bridge leading into her property that spans a small creek. The bridge was damaged by flood waters after a hurricane in 2005 and had to be replaced. The price to remove the old bridge and install a new one was $75,000.

Mark K
02-04-2010, 09:18 AM
It could be as simple/cheap as laying one or two steel corrugated pipes in the drain and covering with a foot of gravel for a couple of thousand $$ or it could go to infinity (nearly) $$. If its just a seasonal drainage swale a couple of feet deep on private property, a few thousand $$ should cover it.

A conservation club I'm associated with installs these on a regular basis and 3-4 hours of backhoe work, a 24" diameter steel pipe, 20' long with a couple loads of crushed stone on top makes an adequate drainage crossing for about $2,000.

I was appraising a 150 ac. tract (had to cross a creek for access) where the owners were working to get a bridge approved and after two years they had close to $40K in design, legal fees, and permits and were still waiting for approval from the DNR and the Dept. of Envir. Mgmt. but they were building in a flood zone.

100K lb. capacity isn't a bad idea. If they plan to build on the site, a loaded concrete truck will weigh over 60K.

Price would depend on how many gov't agencies want control, depth of the drainage and the clear span of the bridge. If you're in western Michigan, the ground is mostly sand and packs very easily for a good foundation. I lived there for a few years and was amazed at how hard and well drained the sandy soil was.

Ted Martin
02-04-2010, 09:29 AM
100k is probably a minimum load if there are improvements on the property since that is what would likely be required for the fire department pumper and tanker to access the property.

If you can find one, a railroad flat car makes a nice bridge. All you need to build are the headwalls and have a crane drop in in place and you are pretty much done.

Cost guide from the federal disaster loan program:

Pedestrian (Wood/Steel) SF $24 - $60
Car / Light Truck (Wood/Steel SF $45 - $90
Bridge Foundation, Win Walls Abutments SF $25 - $55
Bridge Engineering (5% to 15% of Total Cost)

residentialguy
02-04-2010, 10:03 AM
The I-35W bridge boondoggle in MN costs $234 million! :Eyecrazy:



....that might be a bit of overkill for your scenario.

redfish
02-04-2010, 11:05 AM
Problem with calling contractors to get estimates......well just imagine throwing out appraisal fees to some guy. I would call some golf courses.

Elliott
02-04-2010, 11:12 AM
I have a second home in a small subdivision and we had an old bridge
made of logs that had to be replaced. The local fellow who does snow
removal work and has construction equipment, found and bought
the bed of an old railroad flat car, spans 40 or 50 feet. I think the
flat car bed was $4 or $5K delivered. I think our total cost was $12K.

Mike Boyd
02-04-2010, 12:28 PM
I had a similar situation and I merely installed a culvert, as Mark wrote about. On the inlet side you have to build a bulkhead that won't erode away during a heavy storm. For asthetics, I framed up a roof over the driveway so that it appeared to be a covered bridge. You can get corregated galvanized steel culvert up to 4' in diameter. If I recall, I used a 2' diameter pipe and it got clogged one year and overflowed flooding my garage. You may have to get a permit from fish and game. I didn't bother.

Couch Potato
02-04-2010, 03:02 PM
Mike, you might want to edit your post. It could get expensive if some fool were to pursue the "environmental damage" you did. :rof:

Mike Boyd
02-04-2010, 03:24 PM
Mike, you might want to edit your post. It could get expensive if some fool were to pursue the "environmental damage" you did. :rof:

There has NEVER been a fish or crawdad in that drainage ditch! Maybe a rattlesnake or 2, field mice, a rabid fox crossed it once before I shot it, deer crossed it all the time but I never shot any of those. LOL

JRS at OBX
02-04-2010, 03:34 PM
Just hope the Audubon Society doesn't get involved. We are trying to replace a bridge over Oregon Inlet which should be about a mile and a half. The tree huggers and bird lovers think it would be a better idea to build a 17 mile bridge so no bird nests would be disturbed.