A septic tank riser: The definite guide on how to make one diy

A septic tank riser (or manhole extension) is a metal, fiberglass, or plastic pipe that is installed between the soil and the septic tank to make it easier to access the tank. It is a short tube that can range in depth and width.

Septic tanks are often buried so that they don’t take up space in your garden. They contain sewage and burying them keeps the smell away from your home. While septic tanks can process a lot of sewage, they still need to be cleaned every 3-5 years. Inspecting them from time to time is also necessary. A raiser makes this easy to do.

It creates a lid in your garden that can be opened to reach the tank. Some systems don’t have this and when the tank has to be drained, they have to open up your garden. This can create a mess and it is possible that they don’t find the location so it can cost more to find the tank.


Advantages of a septic tank riser

A tank riser can help you to check if the tank is full and needs to be drained. There are several things that affect how fast your tank gets full:

-The size of the tank

-How many people use the toilets

-The size of the drain field

-The climate

-How well the tank processes sewage

All of these can affect how often you have to drain the tank. This makes it necessary to check the status from time to time. We have discussed how to do this here. You can wait until a certain time period has passed but this can make it too early or too late to drain it. Don’t wait until you have toilets that don’t drain well anymore as it can take some time before the service company can pass by to drain your tank.  You can add some concrete to make the ground more stable around the riser.

It can be a good investment to install a sewer riser as companies charge more to pump out a sewage system without a raiser than with it. You can get your investment back after a few pumps so over the lifetime of your tank, you will probably run breakeven. Therefore the cost aspect shouldn’t be a decisive factor to determine if you want a raiser or not. A riser can increase the value of your home in some locations. Check with your real estate agent if that is the case in your area. 

It can also allow you to inspect the tank and add liquids to the tank if needed. It can make it easier to detect and fix a problem.

Septic tanks have to be drained completely and this is easier to do when there is a tank raiser. If the service technician had to dig a hole in the ground, they might find it harder to reach the bottom of the tank and this can make it less clean than it should be. 

Some older homes have the tank inside the house and then a septic tank riser is needed so that it is possible to drain the tank. This is not recommended though as it releases bad smells and flies in your house. Nowadays this is not a common practice except in some cities that don’t have a sewage system nearby. In a lot of cities, this is even forbidden as it is not that hygienic. 

How to install a septic tank riser: DIY

Installing a riser by yourself is often easy, as shown in the above video. You just need to have the right materials and make sure that you add enough dirt around it. You have to know the size of the riser so that you can get the right one. Once you have this, you have to dig around the top of the tank.

Septic tank risers are just plastic rings that are installed on top of the existing holes. Make sure to use plastic that is strong enough and can handle the temperatures in your area. PE or PVC are often used as a material for this.

You can use cement to connect them to the other parts of the tank. This keeps them in place and makes sure that water doesn’t get between the septic riser and the septic tank. Add dirt and soil around this to make sure that the structure stays in place.

You might have to reduce the size of the top of the tank. This makes sure that it gets through the riser. Add the lid and the dirt. Make sure that no rain or dirt gets in your tank while you do this.

Most tanks have 2 holes so you might opt to install 2 risers as well but that is not really needed.

Make sure to mark the septic tank risers so that it is easy to find them. It is also important that people don’t go near them as they can get crushed if you drive over them.

Disadvantages of a septic tank riser 

Septic tan risers cost quite a lot of money. This often ranges from 500-1000 USD, depending on your system. There are cheaper plastic risers that cost less money and more durable concrete systems that are more expensive. Most people install a septic tank riser when they install a new septic tank. If you install one with an existing tank, it is essential that the tank gets inspected to make sure that it is able to last for a long time. 

If there is a problem with the lid of the riser, it can release bad odors or even sewage flies. These are no fun and can be annoying to deal with. Removing the top of the tank to pump it without a raiser is quite easy if you know the location.

A riser can also be dangerous. Kids can open it up while they are playing if it is not locked properly. Furthermore, people can fall into the sewage tank if they are not careful. It is just a hole in the ground so you can trip or fall in it. You can get a safety screen though to remove this objection.

A septic tank riser also has a plastic or concrete lid that is visible in your garden. This can decrease the aesthetics of the garden as you can’t grow things around this area. You have to be careful when you mow the grass so that it doesn’t get damaged.

It can also get damaged by a heavy vehicle that drives over it. The riser has to be properly installed or it can sink away when there is a lot of rain. It is possible that you have to replace the riser after several decades if there is a problem but these are exceptional situations. 

Is it necessary to have a raiser in your garden?

No, your system can without it. It can be great to inspect it from time to time though so a riser can be a wise investment if you want to make sure that your septic tank works well. If it doesn’t process the waste, you have to pump it more often or even work on the system. It also makes it easier to troubleshoot when there is a problem with your septic system, such as a drain field that doesn’t spread the sewage out well or clogs in your drains. 

 It often comes with new systems as people see the advantage of it. A lot of manufacturers and installers of septic systems recommend that you pay more for the septic riser. You can argue if the added cost and the space that it takes up are worth it is given that you don’t have to clean your septic system that often.

Septic systems can last a long time. For this reason, it is important that you study the best solution for your home. If you don’t, you might end up with a lot of clogged drains and other problems. Make sure to work with a specialized company before you install a septic system.