New Septic Tank Cracked

[rutwad]

My neighbor had a septic tank just installed. With over 3"'s of rain just 2 days after installing it, the hole and tank were both completely filled with water. A trench was dug to drain the water from the hole. Then we noticed that on one side of the tank at the bottom, the weight of the mud/water seemed to have pushed in on the concrete enough to crack and bust part of the side. The crack runs completely from top to bottom, but the hole appears to be approx. 15" long and 8" tall at the very bottom of the side wall.

I am shocked that the concrete would not withstand the pressure. Does anyone know what the minimum wall thickness is required for a small residential precast concrete tank? I think the wall may have been too thin, previously cracked, or something else.

 

[Treemonkey1000]

That is pretty bizzare. I am surprised that a Fiberglass tank wasn't used. From the few tanks I have seen they were 2" thick. Most of the tanks that I am familiar with were installed 20-40 years ago and never had problems.
I am thinking it was loaded onto the truck for delivery improperly or dropped into the hole improperly.

 

[rutwad]

That's what I am thinking. Maybe it was already cracked, was made of poor concrete, or maybe a small section of the wall ended up being too thin.

 

[Treemonkey1000]

Is the company that sold it or installed it going to replace it? It could be patched probably but why not start out with one that is right from the get-go? They don't want that system malfunctioning for the next 20 years...

 

[LBrown59]

I'd be knocking on the partys door that sold me this defect real hard real quick.

My neighbor had a septic tank just installed. With over 3"'s of rain just 2 days after installing it, the hole and tank were both completely filled with water. A trench was dug to drain the water from the hole. Then we noticed that on one side of the tank at the bottom, the weight of the mud/water seemed to have pushed in on the concrete enough to crack and bust part of the side. The crack runs completely from top to bottom, but the hole appears to be approx. 15" long and 8" tall at the very bottom of the side wall.

I am shocked that the concrete would not withstand the pressure. Does anyone know what the minimum wall thickness is required for a small residential precast concrete tank? I think the wall may have been too thin, previously cracked, or something else.

 

[rutwad]

I guess I will start with the tank manufacturer and see what he is willing to do. Sometimes you can attract more flies with honey than with .......

 

[atgreene]

It will not pass an inspection. It will need to be replaced and any company worth anything at all will change it out.

It may have been the water pressure, but could it have lifted? I've had a few float in wet ground when a heavy rain hits unexpectedly. Not fun at all.

 

[rutwad]

I've heard they will float, but I would not want to be rescued at sea with one.
It will most likely be replaced, but I just wanted to get other opinions to make sure.

 

[Danno1]

I guess I will start with the tank manufacturer and see what he is willing to do. Sometimes you can attract more flies with honey than with .......

Sometimes you can attract more flys if you drive the honey wagon..........

.

 

[WVBill]

I guess I will start with the tank manufacturer and see what he is willing to do. Sometimes you can attract more flies with honey than with .......

I think I'd start with the Installer - he was the last one to "touch" the tank. Was it bought directly from the manufacturer or through the installer?
May come to a pointing match between the two but let them sort it out.
My $.02...

 

[philgreen]

WVBill has it right. Start with the installer, let him talk with his tank supplier. That is not an arguement you want to have.

If you have not already cut a check, hold on to it until somebody repaces that tank. Concrete tank suppliers do a volume business, one tank shouldn't kill them. Your installer, if he is any good, should want to make this right.

My two cents...

Phil

 

[schmism]

my concrete tank is like 4" thick. unlikely it cracked from ground pressures and was likely cracked due to poor handling/manufacturing before it was set.

 

[Lasgambler]

The tanks we install here in Arizona are rectangler shaped. We have a choice of one peice or two peice tanks. They are about 4 inches thick.

We are required to fill with water after partial back fill and before inspection.

Was your tank filled with water before the storm? Terry

 

[LBrown59]

We are required to fill with water after partial back fill and before inspection.

That's to keep em from floating.

WVBill has it right. Start with the installer, let him talk with his tank supplier. That is not an arguement you want to have.

If you have not already cut a check, hold on to it until somebody repaces that tank. Concrete tank suppliers do a volume business, one tank shouldn't kill them. Your installer, if he is any good, should want to make this right.

*My two cents...

Phil

*I'l chip in another 2 cents.

 

[Lasgambler]

That's to keep em from floating.

LBrown59 That is true that they could float out of the ground. It would be possible for that to happen here during Monsoon Season. We get all our rain at once then none for the rest of the year. I agree with you on this point and get a big kick out of thinking of it floating out of the ground in the desert. Alot of the time I wish I had to worry about that.

The counties take is to make sure the tank is not in the condition as the one that started this thread and will hold poo.
Terry

 

[Ranger Rick]

That's to keep em from floating.

LBrown59 That is true that they could float out of the ground. It would be possible for that to happen here during Monsoon Season. We get all our rain at once then none for the rest of the year. I agree with you on this point and get a big kick out of thinking of it floating out of the ground in the desert. Alot of the time I wish I had to worry about that.
Terry

Stranger things could happen. One wet spring we were pumping out a big concrete swimming pool that was on top of a big hill. Well the crew went to lunch with the pumps running and when they came back and the swimming pool had floated out of the ground about a foot. They had tear the hole thing out to fix it. I can still hear the bosses saying fill it back up may be it will go back in the ground. LOL Sorry to get off the subject Rick

 

[MarkV]

I was wondering if it had any water in it also. The last one I had put in was plastic and you had to fill it with a foot of water, then a foot of backfill over and over to balance the pressure on the tank.

Either way it sounds like an installer or manufacture problem.

MarkV

 

[rutwad]

We did not fill it with water, but the lids were open.

Tank supplier agreed to replace. Looks like it was a bad mix of concrete.
Thanks for the input.

 

[Treemonkey1000]

Cra&&y concrete in a septic tank? Now that is funny

 

[JoelD]

Great to hear it all worked out.

Joel