Loader Culvert replacement - How big?

[Coyote machine]

1/2 size increase to 18'' from 12" increases volume of water able to pass through by 5 times!
AND HDPE flat bottom, (interior) reduces chance of rock/sediment clogging.
Our town is replacing LOTS of clogged/rusted out smaller diameter culverts. Also, with the weather being what it is these days- bigger definitely is better, for now and going forward.

 

[Grandad4]

Adequate drainage is indeed a concern. But looking at Stbill's pictures, I'm not seeing how to fit in a larger diameter culvert and also add topfill material above it. His smaller culvert is already barely covered underneath his driveway, which appears to be level and on grade with the road, and the ditch looks quite shallow (pictures can be deceiving). Seems to me to make his culvert bigger and also cover it with something like 12" of material, he'd have to either re-dig the entire ditchline along the road a foot or more deeper or he'd need to build an 18-24" whoop-de-doo hump over that culvert. If it were my place, I wouldn't want to do either. Maybe a better answer would be doubling up with a second culvert.

Because of the shallow cover, another steel or even concrete culvert might offer more strength than HDPE. Also, we've found packing the culvert in crusher run , stone dust or similar material seems to help carry traffic loads because it packs so tightly over time.

 

[paulharvey]

If cover is the concern ERCP (eliptical reinforced concrete pipe) is the answer. 12"x18" ERCP would be fine wouldn't it.

 

[stlbill]

Hello all,

Thank you for the abundance of information!

I decided to take FTG-05's advice (a big personal thank you!) and try to clear the culvert. It would save the cost of a new culvert... at least until we get enough rain to verify the pipe can handle all the runoff.

@PSDSTu: This is a private subdivision project and not on a county road.

The 260 backhoe exceeded my expectation on this now tiny effort.

I used the 16" tooth bucket to expose the downstream end of the culvert giving water a place to exit. Then I switched to the smaller Bro-Tek Ripper/Plow bucket and in two quick passes made a ditch downstream of the culvert all the way to the tree line. The ripper/plow earned it's keep for this one task alone because with the 16" bucket I could not dig into the rocky ground using the dipper circuit. It was troublesome enough to switch buckets that a hand shovel proved easier to move the pile at the end of the ditch.

Once the downstream end of the culvert was exposed we used just about anything we could to chip away at hard clay and roots occupying the culvert. Eventually we achieved daylight - a horizon really. The bottom half of the pipe is still clogged about 4 feet in, but we expect rain will quickly erode it (see below - still waiting to know if we are right).

I also spread 2 yards of 1 inch clean gravel where water had washed. I am mad at myself for not matching it better. Now I have to do the whole thing in limestone color. :thumbdown:

It has been about a month and St. Louis is still waiting on enough rain to tell if the pipe is fixed or not.

Here are the photos:

 

[stlbill]

I forgot to add:

When we ever get enough rain to find out of this is fixed, and it turns out not to be fixed, the plan is to power wash the remaining clog and debris. I have a 4200 PSI @ 4 gallon per minute power washer and 275 gallon water tote. The part of that plan not complete - which has kept us from doing it already - is not having clean water at the job site, electric to pump clean water from an on-site 1 acre fishing lake, or a truck and tandem trailer to haul the tote full of water from someone's house.

 

[FTG-05]

You're welcome! Remember, even a blind squirrel finds a nut every once in a while!

BTW, where do you live? That street sign, does it really, really say "Skinny Hoes Unite!"??? And what kind of person are you that would live on a street named that????

 

[stlbill]

Thanks, I needed a chuckle! Been a busy day at the office! The sign says "Sunny Acres Lake". Hopefully nobody else misreads the sign like you did! This is a fishing lake in a private residential subdivision near St. Louis, Missouri. We have all the normal problems of any property owners group starting with residents who don't pay their property assessment resulting in some overdue repairs. Missouri law leaves little recourse for collection until the property changes hands or the amount owed exceeds a large portion of the lot value. Our new board is trying hard and we are not paid any salary. If you want to know more visit Sunny Acres Estates. Thanks again for your suggestion!

 

[Coyote machine]

I forgot to add:

When we ever get enough rain to find out of this is fixed, and it turns out not to be fixed, the plan is to power wash the remaining clog and debris. I have a 4200 PSI @ 4 gallon per minute power washer and 275 gallon water tote. The part of that plan not complete - which has kept us from doing it already - is not having clean water at the job site, electric to pump clean water from an on-site 1 acre fishing lake, or a truck and tandem trailer to haul the tote full of water from someone's house.

Do you have a local fire dept that could come out and flush the culvert, for perhaps a donation?
Your stone will mix in eventually. Better to have some of a different color than none of the right color....

 

[FTG-05]

Oh, OK my bad! I guess you're alright after all! :drink: