Culvert Advise 8"

[rich_ncal]

I am thinking of adding a culvert pipe under the end of my driveway for drainage. My gravel driveway enters a paved through road on a slope. Currently storm water flows over the driveway in a v-groove in the gravel driveway. During very heavy storms some of the gravel erodes creating a mess on paved road.

At the local contractor supply store there is both steel culvert pipe and plastic culvert pipe.

I was considering the 8" smooth lined plastic culvert pipe. What are the advantages of the steel verses the plastic pipe? According the supply store the 8" plastic pipe should be buried about 12" deep under a driveway. Can the 8" steel culvert material be buried at less depth?

 

[EddieWalker]

I'm at a loss as to any advantage to metal culverts. They rust, dent and catch debri.

Plastic will never rust, it has a smooth bore that lets material flow through easily and if you hit it, it flexes and bends back.

I've never put anything smaller than 12 inches in and never even thought a smaller one existed. I can get a 12 inch culvert at Lowes for $120 and my farm store is just over $100. Prices might be different for you.

Set it on a solid base, fill real good all the way around with at least a foot of material over the top. If you have four inches of gravel, then 8 inches of dirt or sand will work just fine.

Eddie

 

[rich_ncal]

Thanks for the advice.

In addition to the 8" material the local contractor plumbing supply store had 6" plastic and steel culvert material. They also have a good selection of larger diameters. The 8" plastic culvert pipe with the smooth inner liner was $100 for 20' lengths.

The local Home Depot did not have any, I did ask for help to find this when at the Home Depot.

 

[shvl73]

Around here alot of lumber yards stock the plastic double wall culverts. They are plenty strong. I recently put in a 12" one and had a tri-axle load of dirt delivered, 75,000lbs, no problem with the culvert taking the weight. I have seen some single wall ones around that are corregated inside, I would avoid those, they'll trap dirt and debris as previously stated. The galvanized ones will rust out, mine have.

 

[PineRidge]

Like Eddie said, here's one application where plastic is preferred over the steel pipe. Because of our business we have had lots of trucks coming and going over the plastic culvert pipe in the past 7 years and it has always held up without problem.

 

[CharlieTR]

When I put my culvert in I was required to get a permit from TxDOT (TX dept of trans). They came out measured the ditch depth, and said I must have 18" pipe with "safty ends". 2 foot ditch with 18" pipe and 6" dirt on top. They had some rules about radius of the driveway and width for private/commercial. They did a great diagram and that is one permit I am glad I got. The old timers told me they use to put them in, but not these days.

I have seen the plastic pipes on trucks, but never saw the plastic safety ends before. Are they plastic too?

 

[drm]

...I was considering the 8" smooth lined plastic culvert pipe. What are the advantages of the steel verses the plastic pipe? According the supply store the 8" plastic pipe should be buried about 12" deep under a driveway. Can the 8" steel culvert material be buried at less depth?

Yes, the steel can be buried with less cover. I have both the plastic double wall and the galvanized. The plastic is 18" and buried with almost 12" of cover. The steel is 16" and has 6 to 8" of cover. I went with the steel on the second since I did not have enough height for the 12” of cover. I have had loaded triaxles, loaded tractor trailer dump trucks, moving vans, and every other kind of truck over them in the past two years and they are both doing well.

I would not go any less than 12" diameter and would like more to reduce the chance of clogging. Be sure to get the Highway Occupancy Permit requirements for the drive and culvert/ditch. They may list a minimum size they would allow.

Most important part of installation is the base and backfill around the pipe. Good base and backfill tight around the pipe with a compacting angular gravel fill.

 

[Egon]

Culverts come in different strength's for the same size pipe.

 

[rich_ncal]

Thanks for the inputs.

The through road at the end of my driveway is a private road shared by five properties. So this does not impact a public right of way or public road easement. From what I can tell the county considers this culvert a minor grading project that does not require a permit.

Slightly off subject: My neighbor on the down hill side of my property across the public county road did some grading on his side of the road when he put in a barn and coral. A result was to limit the flow of the water through a culvert under the county road. So now the county road floods during heavy rain. This year the county transportation department placed a temporary road flooded sign out during periods of very heavy rain. I doubt the county has figured out that there are changes to my neighbor’s property that have changed the drainage. In this county a small barn with no power or plumbing does not need inspections and has very limited permit requirements. My changes will help to pull water off the private road. Regardless all paths from my property and a few other properties drain to the culvert under the county road.

I will try the 8” lined plastic pipe under my gravel driveway. I will let that go for a few years before I set this work under pavement to see if that is the final solution.

 

[gordon21]

Buy smooth plastic or use smooth concrete. Corrugated pipe is only good for residential projects if it is 18" or larger. The small stuff clogs up too easily. Ask around at your public local water supply. They may have scraps of water main pipe for free or minimal cost. It would be super strong, smooth wall and cheap. A utility would think nothing about giving away a 12' piece of 12"-24" heavy wall PVC pipe.