Driving over a septic tank

[aircommuter]

You must know all conditions to rate loads. Consider the fact that this tank is 20’ from a single car garage and centered with the doorway. The car’s wheels are nearly aligned with edges. The capacity is only varying by the misalignment of the car without running into the garage itself.
The concrete is 4000 psi material. Rebar is grade 60. Now punch it in and see what you get.

 

[Willman]

Don't do it. Nothing goes over my tank or leach field bigger than a zero turn mower.

Same here

 

[aircommuter]

To each his own. When I was in the business of installing septic tanks and restaurant grease traps (same thing without leach fields) dozens were installed in driveways and parking lots. It’s just a matter of design.

 

[paulsharvey]

To each his own. When I was in the business of installing septic tanks and restaurant grease traps (same thing without leach fields) dozens were installed in driveways and parking lots. It’s just a matter of design.

100%, manhole, drainage structures, ect. Its not hard to design traffic rated structures. However, most septic tanks are not traffic rated. Without knowing, I would avoid unnecessary traffic on one.

 

[aircommuter]

We call it H20 load rating. Pretty low cost for the tank. Usually it was $100. Those lids are much pricier. Close to $900. I just used the rated tank in case someone wanted to do the lids later.

 

[JTKub]

.....Its not hard to design traffic rated structures. However, most septic tanks are not traffic rated. Without knowing, I would avoid unnecessary traffic on one.

Exactly. My 50yr/old gravel leach field system is deep and my 1000 gal concrete tank is 2-3ft underground. I still avoid it with my SCUT when it's been wet out and the ground is soft, but it would take a lot to damage the system. I can use my Craftsman rider over it any time. My brother just had his old system replaced with a ~$25K sand filter system. Not sure I'd drive over that for quite some time. Sand filter systems are all you can install in my area. Been this way for probably 30+ years.

 

[4570Man]

100%, manhole, drainage structures, ect. Its not hard to design traffic rated structures. However, most septic tanks are not traffic rated. Without knowing, I would avoid unnecessary traffic on one.

Locally I can buy a concrete 1,000 gallon tank for $1,000 delivered and set. I bet a traffic rated tank would be 10 times that amount.

 

[Gord Baker]

Tank covers must be accessible at ground level due to local code. The lid is 6” thick with #6 rebar on 12” centers and # 4 rebar on 6” centers. The tank was existing about 20’ from the garage. They have been driving over it for 20 years. I am a general engineering contractor since 1980. I haven’t done little jobs like that since the mid 80s. That was just helping my neighbor. Oh yes those T fitting outlets are standard code also for at least the last 50 years around here.

Your environment must be far South of the Canadian Border.
Are 'covers and lids' the same thing in your note? If the rebar was properly located mid thickness of the slab, It should be substantial.
In calculations, the weight of the Lid and cover must also be included. Yours would weigh about 300# per foot in 2 directions plus cover.
You could always run a pipe down to tanks buried 4' I guess, for cleanout.
Good luck with it. Do you have a Weir inside the tank?

 

[aircommuter]

Your environment must be far South of the Canadian Border.
Are 'covers and lids' the same thing in your note? If the rebar was properly located mid thickness of the slab, It should be substantial.
In calculations, the weight of the Lid and cover must also be included. Yours would weigh about 300# per foot in 2 directions plus cover.
You could always run a pipe down to tanks buried 4' I guess, for cleanout.
Good luck with it. Do you have a Weir inside the tank?

The tank is original before I made the lid there a weir which partially supports the lid as well. Yes we have installations that are deeper for certain reasons and we installed risers as needed. Typically system design in the areas where I worked had the tank as shallow as possible because the deeper you go the worse the soil. Put the tank too deep then one may have to pump up to the leach field since most percolation is nearer the surface. There are always lots of variables. Hillsides, rocky soil sandy and more. I have installed mound systems, vertical bored systems, gravity dosing systems pressure dosing systems etc. The biggest system was about 35 years ago using just over 1000 tons of drain rock, with a 6000 gallon capacity which was 4 tanks together two without ends and two with only one end. Everything had to be perfect. It was a pump dosing system with three computer operated butterfly valves to alternate between the leach fields. No sewage involved. It handled grape washout at a winery. The effluent was used between grape rows to save water. Once we assembled the tanks we had to go inside all suited up with a pressure breathing apparatus and coat them with coal tar epoxy since the grape washout has PH of around 3. Concrete tanks would only last a year or so without it. Price at the time was $100k. Today??$$$$$. It’s California so figure double what you are used to and you may be close.

 

[Gem99ultra]

I can give you some very unpleasant first-hand thoughts about driving your tractor over a septic tank. I buried a Ford N8 in one once. Considering the N8 weighed less than 3K pounds, I'd suggest you NOT drive over it even if it does have a concrete lid.