How To Find Your Septic Tank: Step-by-Step Guide


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How to Find Where Your Septic Tank is Located

While it may sometimes be tricky to locate your septic tank, since its whereabouts are not meant to be a big secret, there are going to be ways and means for you to find out exactly where it is located.

Here are a few simple and practical methods you can use to help locate your septic tank:

1.  Consult a Septic Tank Diagram or Map

This is the easiest way to find your septic tank, as it will indicate exactly where the tank and drain field is located on the property.

If you have recently purchased the property, the septic tank map/diagram should be included with the house plans and inspection paperwork.

If not, it may be available from your local health department, which typically keeps septic system records on file, or alternatively, your municipality may have a property survey map that might indicate the location of your septic tank.

septic tank drawing

If you have purchased an older home, the information available may be sketchy at best, or there may not be any records available on file at all.

If you are unable to find a map or diagram pinpointing the location of your septic tank, it may be worthwhile to create your own.

You can keep your newly created map on file to give to the next homeowner should you wish to sell your property in the future, but first, you have to have some fun searching for your septic tank.

2.  Follow the Sewer Outlet Pipes

The easiest way to find your septic tank is to follow the pipes that come out of your home and extend into your yard.

First, you will need to find the main sewer outlet pipe, a 4-inch diameter pipe that will most likely be found in your basement or in the crawl space under your home.

how to find your septic tank

If you have a finished basement in your home, this can often mean that the septic tank would have to go quite deep in the ground. To prevent these great depths of septic tanks, a sump pump or sump station is often used. This station will then pump the home’s sewage up close to the grade and then to the septic tank.

how to locate your septic tank

Make a note of where the pipe exits the wall, then go outside to the area where the pipe exits into the yard. Using a thin metal stake as a probe, follow the pipeline, probing the soil every 2 feet or so.

Septic tanks are usually located 10 to 25 feet away from the home and no closer than about 3 feet, depending on where you are from.

When the probe strikes a flat concrete, polyethylene, or fibreglass surface, you will know you have located your target and have found what you are looking for.

Alternatively, you can use a drain snake that is normally used to unclog a blocked drain or toilet to help you locate your tank.

Insert the snake into an inspection/rodding eye and thread it through the sewer pipe line, taking note of any turns as it snakes its way through the pipe.

When it comes to a halt, it has probably reached the septic tank. Make a note of how far the snake was extended, together with the direction and angle of any bends, as you pull it back through the pipe.

Now that you have an idea of how far the snake traveled, together with its approximate route, you can scout around in the vicinity of where you expect the tank to be buried.

Or you could go the hi-tech route and flush an electronic transmitter down the loo, which will send out a signal that can be tracked with a receiver. Where the signal is strongest is most likely where your septic tank is located.

finding a septic tank

You can obtain one of these handy gadgets from a rental or plumbing store, tank cleaning company, or authorized person.

In the winter months, there is often snowmelt around the septic tank area.  This may be difficult to see at first with heavy snowfalls, but as the temperature starts to warm up most of the time, the snow clears much quicker around the tank area.  

snow melt around septic tank

3. Search Your Yard

A septic tank is typically buried underground so that its presence is relatively inconspicuous rather than glaringly obvious. As time goes by and vegetation grows, it can become difficult to discern the visual markers that originally indicated where the septic tank location is.

But with a little persistence and sleuth work you should be able to find your tank.

The first thing you need to do is rule out areas where the tank is not likely to be.

This includes any area less than 3 feet from your house; under your driveway or other paved surfaces; typically underneath patios, but we have seen a few under decks or other built structures; the area adjacent to your well; and areas containing trees or that are heavily planted with woody shrubs.  

Here in British Columbia, we are required to have a 100-foot setback distance from bodies of water, including wells.  

Once you have determined where the tank is not likely to be, you can start having fun searching for clues in the areas remaining. Take a walk around your property, keeping an eye out for subtle clues such as raised or sunken areas that could indicate a tank is buried underneath or could be located nearby.

  • Also, take note of the growth patterns of your lawn. An area of lush growth may be fueled by nutrients and water supplied by effluent from the drain field, indicating your septic tank could be nearby.

On the other hand, a tank that is buried just under the surface, leaving only a shallow depth of soil between the tank and the surface, may hinder grass growth, resulting in patchy areas where grass struggles to grow. Take note of these signs as they may point to your septic tank.

  • Follow the sewer line leading from your home, gauge where the line leads out of your home, pay attention to the grade it is at in comparison to the outside ground level.  Follow in the same line of travel keeping in mind the sewer pipes line has a pitch from 2-3% to allow flow into the tank.
  • Keep an eye out for caps or valve boxes, these will normally lead to a component of the septic system.  Keep a lookout for electrical boxes or components, often when a pump station is required there will always be an electrical box, control panel or alarm.

4.  Ask 

It never hurts to ask your neighbours, we have often encountered long-term neighbouring homeowners having vast knowledge of historical construction, modifications, or other information about your property.

Real estate agents may also look up records of sewerage for the home, often these documents get passed from one homeowner to the next during property sales.

Give your local pumper truck service a call, many times there will be documented records of maintenance on your septic tank.

You’ve Found Your Septic Tank, Now What?

Once you have found your tank, it is not a good idea to remove the cover and open the tank, as the contents are not only smelly but also give off toxic fumes that are highly flammable and can be lethal.

An open tank poses a danger to anyone walking on your property, and should someone fall inside, the toxic gases inside the tank can result in loss of consciousness and death.

Once you have found the septic tank cover, it’s now time to put your feet up, pour yourself a cold beer, and call in the professionals if any maintenance is needed. Okay, maybe hold that beer for a second; you still have a few things you need to attend to.

Mark It and Map It

To make it easier for yourself and others to find the tank in future, you need to mark its location, as well as the location of the septic lid.

This needn’t be a big flashy sign indicating the whereabouts of the tank, but rather a subtle marker such as a heavy pot plant, garden statue, paving slab, or any other decorative garden feature that is not likely to be moved around too easily, will do.

Also, don’t forget to draw a diagram and/or map showing where the septic tank is on the property.

File this septic tank map or diagram together with your household paperwork so that it is available for you or others to refer to in the future.

Call in the Professionals

Maintenance and repairs of septic systems are not something that should be undertaken by the homeowner; not even by a DIY enthusiast.

This is a job that should be left to a professional.

In British Columbia, it is an offence for anyone other than an Authorized Person (a Professional Engineer or a Registered Practitioner) to construct, install, maintain, or repair a septic system.

An Authorized Person will not only be able to assist with septic tank maintenance and repair work, but if you are struggling to find your tank, they will also be able to help you locate it.

You have just moved into your new home and are still busy settling in and deciding what needs to go where. One thing that new homeowners often take for granted is wastewater disposal, as this may not always be clearly visible, even if wastewater treatment takes place on your property with the help of an onsite septic system.

If wastewater generated by your home is treated by an onsite septic system — which typically consists of a septic tank and a drain field, and in some cases additional treatment stages —  septic tanks need to be maintained and pumped out regularly. But how do you know whether your property has a septic system, and if so, how do you find where the septic tank is located?

While searching for a tank buried underground may seem akin to looking for a needle in a proverbial haystack, especially if you have a large yard, it may be far easier than you think.

There are a number of ways to determine if you have a septic system and to find out where the septic tank is located on your property.

First, it helps to have a clearer understanding of how a septic system functions and the role the septic tank plays in treating the wastewater generated by your home, and why you should know where your tank is located.


If you are unsure whether your property has a septic tank or not, or simply don’t know where it is located on your property, there is no need to go into panic mode just yet.

While locating a septic tank buried underground may seem like an impossible task, it needn’t be too daunting.

By following these tried and tested methods outlined above, you should not only be able to determine whether your home has a septic tank, but you should be able to pinpoint the location of your tank without too much difficulty. Just take care not to do anything too risky.

Send us a question, feedback or other ideas.

Other Septic Tank FAQ

How to Find Your Septic Tank Lid

When you find your septic tank, you can give yourself a pat on the back for your excellent sleuth work. However, the game’s not quite over yet.

You still need to find out where the septic tank lid is located.

Using your metal soil probe, probe around to find the edges of the tank, bearing in mind that septic tanks are typically rectangular in shape, measuring around eight feet long by five feet wide.

finding septic tank cover

Once you have found the edges, mark the outline of the tank and then continue probing within that outline in search of the cover. If you can’t find it using the metal soil probe, you will need to shovel away the soil covering the tank until you find the cover/s (there may be two lids if the septic tank has two compartments).

How Do I Find My Septic Tank Cleanout?

When locating the home’s sewer line and where it leads out of the home, there will often be a cap that can be removed. This is where a cleanout for the sewer line is that connects from your home to your septic tank location.

In many circumstances, there will also be a cleanout located directly outside and next to the home, look for a cap that may be uncovered. This cap will lead to a ‘Y’ fitting that connects to the sewer line leading to the tank.

How to Find Out Whether Your Property Has a Septic Tank

If you are not sure whether your home is serviced by the municipal sewer or whether it has a septic tank, there are a number of ways to find out.

The first thing you can do is to closely examine your water bill to see if you are being billed for sewer services.

If your water bill reflects a charge of zero for sewer or wastewater treatment services, you no doubt have a septic system on your property that takes care of business.

If your home uses well water rather than municipal water, then you probably won’t receive a water bill anyhow.

If there is no water meter connected to the water mains that service your property, you’re probably using well water rather than water supplied by a public water utility.

The area where your property is located can help you determine whether you are likely to be serviced by the public sewer system.

If your property is located in a relatively rural area, it is highly likely that wastewater treatment takes place on-site with the help of a septic system. If you are unsure, you can ask your neighbours.

If the surrounding properties are serviced by onsite septic systems, then chances are, your home is too.

In certain cases, there may be visual clues, such as an artificially created mound, indicating your property has a septic system installed.

Arguably the most foolproof method of confirming whether your property has a septic system or not is to look at the property records.

Building permits are typically only issued once an approved wastewater management system is in place. In the case of a septic system, this will require the submission of a plan and management strategy that will need to be approved by the local health authority.

The building plans/permit for your home should include information regarding the presence or absence of a septic system, and in the case of the former, should indicate where the septic tank is located on the property.

Why Do I Need to Know Where My Septic Tank is Located?

If you are wondering why you even need to figure out where your septic tank is located, there are several important reasons why this is important, including:

  • Avoiding Damage — It is important to know where your tank is so that you don’t inadvertently damage it by parking heavy vehicles on top of it, for example.
  • Landscaping, Building Alterations & Renovations — If you are planning on extending your home, for example, building a patio or deck that could block access to the tank, or even doing some landscaping with deep-rooted plants that could potentially jeopardize the integrity of the septic tank and/or the pipes in the drain field, you need to know where your septic system is sited.
  • Once you know where your septic tank and drain field is located, you can select shallow-rooted plants, such as lawn grass, to plant in these areas.
  • Spotting Problems Early — If you know where your septic tank is buried, you are more likely to spot potential problems before they become major calamities. For example, a pool of water accumulating in the area where your septic system is sited could provide you with a clear warning that your septic system is being overloaded and in danger of failing unless corrective action (for example, pumping out the tank or reducing water usage) is taken.
  • Routine Septic Tank Maintenance & Repairs — You also need to know where your tank is so that you can conduct routine maintenance, such as inspections and having your septic tank pumped, and point out your tank to your plumber should a problem arise. This will not only save you and your plumber time, but as plumbers typically charge by the hour, it will also save you money.

How Far Is The Drain Field From The Septic Tank?

The next component after the septic tank on a conventional septic system is going to be the distribution box. This component is a distribution network for the effluent leaving the tank. The effluent runs into the distribution box by gravity, then is evenly distributed to the segmented field lines leading from the distribution box.

distribution box

The location of the distribution box can be determined by finding the outlet baffle in the septic tank. Of course, following the procedures for tank location above, you should be able to locate the outlet baffle at the distal end of the septic tank, opposite the sewer line entering the tank.

The next approach to locating your septic field drain lines is to follow the path from the distribution box. 

There is no clear distance in the distribution box or drain field from the tank. Do keep in mind that in many areas, the drain field has to be at least 10 feet away from structures that have a perimeter drain.  The drain field also has to be 100 feet from sources of water or wells.

The smaller the lot, the closer the proximity of the distribution box beginning to the septic tank and the drain field to the distribution box.

It will certainly be easy to locate the drain field lines once the distribution box is located. Either through a camera scope or by digging, you should be able to find the field area by chasing the pipes leading out of the distribution box.

Look for large open areas for the drain field, this can often be a large, well-grassed area. At times, there could be lush green grass over the field area that can be noted. Often, drain field lines can be 50 feet or more in length, with multiple lines running in parallel to one another.

Often, the drain field lines are kept at least 10 feet away from the lot lines.

Luis Goncalves, ROWP, IN, PL

I fell into this amazing trade quite by accident, I have always loved being around heavy machinery and moving earth and in contrast love working with designing things.  This trade in the septic field has led me down a wonderful path of exploring all of my skills and passions while working hard at achieving success.

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