How To Design A Septic System

Many homeowners are installing septic systems because they see them as a better option to the public sewer systems. They tend to be better for the environment because they rely on naturally occurring bacteria to dispose of waste rather than chemicals.

Other homeowners live in areas that aren’t served by a centralized public wastewater treatment system. About 20% of homes in America rely on septic systems.

When you’re planning out a septic system for a property, you have to start with the planning and design. It’s an exact process, as your measurements have to be just right.

Keep reading to find out everything you need to know about designing a septic system.

Local Laws and Regulations

Any major project like a septic system installation means that you need to make sure that your project is within the laws and regulations of your town.

The laws that oversee septic systems will depend on where you are and the scope of your project. For example, in Pennsylvania, the local municipalities and townships will be responsible for septic tanks under 10,000 gallons.

Anything over 10,000 gallons will fall under the jurisdiction of the State Department of Environmental Protection.

It’s incredibly important to be up to speed with the regulations in your area before you start the design process. You might find that you’re halfway into it and have to start over because you weren’t aware of a law that you have to abide by.

Soil Tests

To work well, the septic system largely depends on the quality of the soil. The type of soil, right down to the type of soil grain can dictate how well your septic system will work.

Soils with flat grains can compact easily. That makes leaching systems an issue when this type of soil is used as fill.

There are thousands of types of soils. These soils don’t exist in isolation. Rather they can all mix and combine in various ways. This creates an infinite number of soil combinations, which can make a soil report challenging.

Depending on your jurisdiction, you may be able to conduct a soil test yourself. However, your best bet is to hire a civil engineer to create a soil report. Civil engineers are trained to use certain methods of testing the soil such as percolation and mantle that is the best for testing for septic systems.

Once you have your soil type and composition, you can refer back to the regulations in your area to find out what type of septic system you need.

Types of Septic Systems

Some health codes will tell you what septic system you need according to your soil type. There are many different types of septic systems.

The most common septic system has a septic tank and a drain field that draws wastewater away from the home and deposits it in the soil where it’s treated.

In this step, you’ll need to consider your septic tank size. In most cases, a 1500 gallon tank is sufficient for residential use.

Size of the Septic Field

Once you know the type of septic system, you can start to map out your septic field. Again, you need to refer to the local regulations to make sure your field falls within them. They may have a say as to how far your field is from your home, property lines, and streams.

Now, you have to take into account the size of your home and the type of soil. A larger home with low draining soil will need a larger septic field.

In Connecticut, they take into account the number of bedrooms, not the number of people. The interesting part about that is the definition of a bedroom. Any room in the home that can be used as a bedroom, such as an exercise room or office counts as a bedroom. That needs to be factored into your calculations.

Plan the Pipes

Your drain field will need to have pipes buried about 30 inches underground. They need to be dug in a way, so there’s a downward slope. That allows gravity to do its thing when draining waste from your septic tank.

List the Required Materials

As you’re finalizing your plans, you’ll need to make a list and budget of the materials for your septic system. You’ll need to know the length of pipes and diameter. You’ll also need to plan for gravel to fill in along with pipe connections and joints.

Get Your Plans Approved

Before you take the next step in going ahead with your project, you’ll need to get your plans approved by your town or county. Who you have to go to will vary by your location. In some places, the country or state will be responsible.

You want to make sure that your plans follow the laws and regulations in your area to a T.

The people that approve these plans have a larger responsibility. It may seem like an inconvenience to you and your project, but there are larger implications if your septic system isn’t working properly.

The immediate impacts are damage to property and property values. Other implications affect local groundwater, lakes, and streams. There could be bacteria from your system that gets into public waterways. That can lead to illness and infections for those people.

Hire an Engineer for Your Project

Designing a septic tank isn’t terribly difficult to do. What makes the process challenging is that it requires you to be precise in your measurements. If you’re off by just a small margin, it could throw your entire project into chaos.

An alternative to designing the septic system yourself is to hire a professional engineer who has experience in septic system design and can create the best system for your home or project.

Are you interested in finding an engineer to help you with your septic system design? List your project today.