Septic systems are the way in which modern society can just flush their waste away with no concerns for what happens after. Most of the time, septic tanks are built with good structural strength to deal with the constant pressure of soil pushing down on the tank and septic drain field.
A specialized septic company can even design tanks that can be parked on and still accessed for routine retrofitting and pumping.
Key Points:
- Driving over a septic tank or drain pipe can cause serious and expensive sewage issues.
- When parking vehicles, choose areas of the yard that are not part of the property’s septic system.
- Consult our chart to determine which type of vehicle is appropriate for a task over a septic system and assess the potential weight to ensure the safety of the system.
Chances are that our home septic system is not this advanced, and driving vehicles, even ones designed to reduce compaction like bobcats and skid steers, may cause problems. Any compression on aerobic septic systems can slow down the dispersal of waste and possibly lead to expensive sewage issues. This article will discuss the dangers of driving a bobcat over septic system components and drain fields.
Is It Safe to Ride a Bobcat Over Your Septic Tank?
While it is technically safe to drive a bobcat over a septic system or septic drain field, there are countless reasons why is a bad idea. Unless your tank was designed by a specialized septic company, it will not be made to any superior spec and cannot deal with unintended pressures. Driving equipment over septic tank zones can lead to expensive septic problems and a stinky situation.
Even though you will not be in immediate damage from driving light machinery over septic tank lids, it can cause expensive problems to the components of the tank. Sewage issues are never fun and never cheap to fix, so adding to the probability of breaking your system by using a bobcat over a septic system is a bad idea.
Even if the tank remains intact, you may jeopardize the drain field or rupture drainage pipes, so it is best to avoid all major septic areas when doing home improvements that require vehicles.
What Happens If You Drive Over a Septic Tank?
Some vehicle-rated septic tank lids exist and are distributed by a specialized septic company for use in parking lots. Homes aren’t usually equipped with these, but knowing if the property septic tank covers can deal with a vehicle is important.
It all comes down to how much total weight, how the force is distributed, and how long the vehicle is there. To address some common scenarios, let’s look at the difference between driving over a septic tank and parking on one.
Driving
There is no rated weight limit for most septic tanks, as any heavyweight will damage the system even if it doesn’t destroy the structure. Severe weight, even for a second, can damage drainage pipes deep underground, and no weight from vehicles should ever occur between a house and the septic tank.
If the ground is wet, then no vehicles, regardless of the weight, should go over the septic tank or drain field as compaction and pipe vulnerability are even more likely.
Parking
Some homes use lawns for parking, and this can result in issues. Unless the septic is designed for it, the tremendous pressure of vehicles parked on soil can build up and prevent microbes from breathing and dispersing the waste.
When it comes time to move the vehicles, parts of the system, including pipes, can become more vulnerable and rupture. Park cars and other vehicles in areas of the yard that are not part of the property’s septic system.
Can It Go Over a Septic Tank?
In general, don’t drive anything over your septic tank. If that is impossible, try to only use the lightest vehicle or machine that can complete the task. If all else fails and you need to move vehicles over your septic system, consult the chart below to see what to use and why.
| Vehicle | Can It Go Over | Dangers |
| Truck | No | Compaction of soil in the leech field and damage to the septic tank lid |
| Car | No | Compaction of drain fields and damage to septic piping |
| Tractor | No | A smaller tractor can make it over the leech field in rare cases, but larger machines should not be taken over any part of the septic system |
| Golf Carts | Yes | It is okay to drive a lightly loaded golf cart over the drain field or septic tank but avoid doing so in one that is full of people and equipment |
| Motorcycle | Yes | Do not drive a motorcycle over the septic lines between the tank and the house, but it can safely ride over the underground septic tank |
| Bicycle | Yes | It is unlikely that a bicycle will cause damage to septic tank piping or even have enough lbs of weight to compact the soil |
| Lawn Mower | Yes | Running a mower over septic tank zones is probably not going to lead to septic system failure |
| Excavator | No | No heavy equipment should ever be run over any part of a septic system, or the extreme pressure could rupture even well-made concrete septic tanks |
| Bobcat | Yes | The skids and weight distribution make it safer for bobcats to move over septic systems than larger heavy equipment, but loads must be limited to avoid compaction in the septic drain field |
| Structure | No | May not be able to access the tank for routine pipe replacement or pumping |
| Garden/Landscaping | No | The entire septic may need to be accessed if a problem ever arises, and any landscaping installed will need to be removed, often costing more and leading to worse looking lawn than one that allowed for easier septic maintenance |
How Many Pounds Can a Septic System Support?
There is no real weight limit assigned to what septic tanks can endure because there are too many factors to consider that aren’t usually previously calculated unless that is a request of the client.
The reason for this is that septic systems, while being a structure, also work with the soil, a living system, to perform the task of waste removal. Any compaction of the soil or damage to the drains and leech fields will result in sewage problems.
The total weight when compaction happens falls far short of what the structural limit would be, and effects like compaction and settling at bad angles, as well as pipe or inlet damage, can happen with very little weight or an improperly placed vehicle.
If you need a system to support vehicles, then custom septic systems can be designed to have parking lots or other structures built on top.
The standard septic system in your home is designed to operate within a lawn that is driven over by nothing heavier than a riding mower. Since the tank, the lid, and the pipes are not reinforced like the commercial tanks are, even one reckless driving or parking job could cost you thousands of dollars in repairs.
Do not risk it, and never drive or park vehicles on home septic systems.
How to Use Heavy Machinery Near a Septic System?
If you need to hire professionals for property repair or modification, there are some steps you can take to save your septic system. The first thing you will want to do is to mark off septic systems and leech fields. Using cones and flags, map out the whole system and make sure that crews can clearly tell they should not work over this area.
When possible, keeping workers off of tanks and drain fields will result in little odds of septic damage following construction.
If the job does require moving over septic components, then steps should be taken to reduce the damage or risk of damage. Avoid machines that have many wheels that sit heavy as they create the worse compaction and the smallest areas of extreme pressure.
Use machines with skids as they spread out the weight of the equipment and load, reducing soil compaction and the chance of drain pipes snapping.
Never park construction vehicles or work trucks on septic systems. Designate areas of the property for things like machine storage and parking to reduce accidental damage to septic tank lids. Always move vehicles deliberately over septic tanks and follow the path that offers the least amount of downward force.
Avoid bumps and obstacles or changing direction, all of which will wear grooves and cause compaction.
Be sure to plan the task out beforehand to reduce the amount of time and frequency that machines need to be on or near a septic system. Think about load limits and where support vehicles can be placed to minimize time on septic systems. Only use the lightest machines with tracks to go over vulnerable components, or you risk causing extensive damage.
When the work is done, use proven soil rehabilitation techniques like core aeration and dethatching to reduce the effects of heavy machines driving on your lawn. Compaction can be reversed, and any drain fields aerated to jumpstart the microbes growing and working.
While the system is rebounding, prevent any traffic, even for traffic and mowing, over the drain field to speed up the process and prevent sewage problems. If you do this, it is safe to drive a bobcat over a septic system.