Driveway Culvert Pipe Rotting

[Mainebearsquirrels]

Hello,
I have a culvert pipe under my driveway by the road that is starting to rot(metal). Does anyone know if I can insert a new plastic culvert pipe into the rotting metal one before it gets any worse?

I bought my house just last year, the driveway is only a few years old, and I never thought to check the culvert pipe. I'm looking for a low cost option to fixing the culvert pipe before it completely rots away and I have to dig everything up.

I haven't looked into pipe sizes yet, so I'm not even sure if this will work. My thought is if the plastic pipe is just a little bit smaller than the metal one, then there wont be too much give. And maybe I can inject some foam or concrete to make up the difference.

Any thoughts are appreciated. Thanks!

[HayZee518]

culverts

I always wondered about that myself. The pipes I've seen are all corrugated with a twist. I guess this is supposed to make them stronger. It would seem so.
Anyway they're all galvanized inside and out. The problem comes on the cut ends. That exposes the steel. Not much zinc there! LPS makes a product called "cold galvanize." It has active zinc particles in it in a solvent base that you spray on steel. You might try grinding down your culvert ends to expose the steel and spraying this product on it. If any, it would extend your service life.
Now about inserting a plastic culvert inside your pipes. Not too keen on that because, have you seen the depth of the corrugations? While the pipe will conduct a heavy flow, once the flow ceases, water is trapped in the corrugations. unless the corrugations are slotted to get rid of standing water, it would seem like a great breeding ground for mosquitoes. I wouldn't want that!
Check it out! But I'd go with the cold galvanize.

[pushkins]

Depending on the internal size you should be able to buy a PVC pipe that will slip inside the existing pipe, it's a common repair. Measure your internal size and go to your local plumbing supply house.

[Mainebearsquirrels]

Thanks guys! The pipes I have seen are rated to carry alot of weight, but that is when they are installed properly with stone, even weight distribution. I'm a little worried if the rotting pipe gives way in one spot it could cause the plastic one to break. Any thoughts?

I believe the pipe is rotting internally as well. Maybe some rivet holes? I'm not too worried about water collecting as I'd just seal off the ends. Although now that im thinking about it, any water stuck in there could expand when it freezes this winter and cause damage to the new pipe. Anyone know how much weight spray foam can support?

[pushkins]

Spray foam has zero support capabilities plus it will degrade in ground and water contact.
As long as you sleeve it with a close match PVC pipe you should be good to go, the PVC (probably sewer) should be schedule 80.
As far as filling any voids you could introduce sand via "flooding" it requires plugging one end (between pipes) on the other end (the higher) you need to mix sand and water and feed it into the void area, the water will carry the sand to the lowest point.
The method is used in engineering repairs to undermined footings and slabs.