The Expert Podcast

If it's working properly at your home it's out of sight out of mind and you never have to deal with it what are we talking about of course we're talking about a septic system septic system isn't something that you discuss frequently as part of owning a home like you would of granite countertops or new siding or energy efficient windows because the septic system is hidden it's literally under the ground and you just want it to work you don't want to have to deal with it you don't even want to think about it because of the subject matter but it may be one of the most important mechanical features of your house.
Look if your electricity goes out for a day because of power outage in the area you can live even if the water gets shut off at your house you can probably survive for a while if your septic system backs up you probably aren't able to use your house for much more than a couple hours it could be a very serious event so what is a septic system how are they designed how can you generate plans for one and what is important to know about as a homeowner.
Well it's basically a system as you know to get rid of waste from your home all of the water-based systems sinks bath toilet shower all go into a drain septic system now if you're on a city sewer system you don't have this just goes into a pipe goes out and the city deals with it but if you are on a locally based septic here's what happens it goes out of your house into a tank and the tank separates things from that and then it goes out to a drain field and it's basically a series of pipes that takes the water from your house and puts it into the soil where it gets filtered and drained back down into nature.
Basically the size of the system is based on the number of bedrooms in the house not the number of bathrooms and it's usually based on either two or three or four bedrooms and that will affect the size of the tank and also how many feet of drain field you need the tank itself has an inlet from the house it separates water sludge and oil and the water is what goes out now you might ask what happens to the oil and the sludge well every few years you have to have it pumped out because it doesn't leave the only thing that leaves is the water the other items stay in the tank now it's not a whole lot but after three four years depending upon the use you have to get it pumped out and this information is taken from deschutes county in oregon but it's similar to most jurisdictions.
And once it goes out into the drain field it goes into a series of pipes with little holes you see these little holes and that's where the water goes into a crushed stone section that's underneath dirt on the top of your property you can't build on top of it you can't you know put an addition on your house you don't want to even pave over it because you need this dirt to help evaporate liquid the design may be one of a number of different things maybe multiple trenches distribution box there's a couple different ways of doing it you have to keep in mind which way there's a slope on your property and that's all designed by your septic expert.
Now here's an example of an aerial view you have your house that goes into the septic tank usually it's concrete sometimes metal sometimes fiberglass although metal is not used that much anymore you also have a line that goes from the septic tank into the drain field if you notice each individual line for the drain field has distances they usually have to be like 10 feet apart so there's not too much water going into one place they have to be 10 feet from a property line usually have to be five feet or so from your house and if you have trees you want to make sure you're not putting too much tree water flow onto this area you also don't want to make sure it's far from any wells that you have that's getting water to your house so all these setbacks are important.
Also they all have to be within an approved area and that approved area is based on the soil type so it drains properly it's not too muddy it's not too compact but also you don't want it too loose where it flows through too quickly and even though it's 10 feet between them you also have to have a certain number un disturbed soil you don't want to dig out this whole thing when this is made you dig a little trench you put that in you want this soil to remain how it was compacted.
When you create a septic system there's a series of inspections you have to inspect the tank you have to inspect the security of the tank the the drain lines and the drain field to make sure they're all secured they're not leaking and they're connected properly and that they have the right slope because there's no pumps on this system it all is done by gravity so you want to make sure the gravity flows the right direction you don't want it flowing backwards because it's going to come back into your house.
Here's an example of some of your setbacks if you have a groundwater supply like a well it's got to be 100 feet from your absorption area that's your drain field that's what they call a drain field it's got to be 50 feet from your septic tank why is it farther away because your drain field is actually emitting the water the liquid into the ground your septic tank itself is sealed in theory but it can leak springs same thing 50 or 100 feet surface waters ground water interceptors has to be a certain distance um man-made cuts meaning that if you have a a hill or a gradient you have to be a certain distance 50 or 25 feet the reason why is you don't want this liquid pouring out the side of a hill going down outside the ground you want this to be underneath the ground.
You also have property lines 10 feet like we talked about water lines has to be 10 feet even though water lines are sealed and the system is sealed you want to make sure they're far enough apart so there's no disturbing of the grade that can create either breaks in the line or interruptions in the flow foundations of any building 10 feet for the drain field 5 feet from the septic tank underground utilities 10 feet from the drain field but there is no limit on the septic tank because the septic tank is sealed so having a wire go next to it or a cable go next to it it's not that big a deal again these are the requirements for the state of oregon in most counties every jurisdiction will have something similar.
So if you're looking to plan out a build on your property you can even draw a little sketch like this it'll have to be approved and you'll have to have a a dep approved contractor create an actual septic plan but you can sketch out your property you can put where your house is or where you're proposing to put a house and you can come up with these distances you know do you have enough area to have enough distance of drain line look if these are let's say these look like 80 foot lines right if you have 480 foot lines that's 300 or so feet of line if your four bedroom house needs 280 feet well that's what you need if it's a two bedroom house and you only need let's say 250 feet of line well now you may be able to have a shorter approved area.
First you have to find out how many feet of drain line you need for the size house that you have you can look that up very easily in your building code once you know that you can see how many drain lines you need make sure they're 10 feet apart if that's what the statute says and draw a little sketch.
Most jurisdictions also require that you have a reserve area meaning that if this system fails at some point 5 years 10 years 20 years 30 years down the road you have to have a a backup area because if you don't what are you going to do if you don't have a way to have your septic handled you don't you don't want to have to abandon your house right so most new systems require a reserve area it doesn't have to be the same size because you can use another type of system a sand filter system we'll talk about another video a little more complex a little more expensive but you're also only going to use this in an emergency if this one fails and you can't rebuild it so this is the cheaper way to do it with these drain lines a sand filter is much more expensive so you want to have enough room for the cheap version and then if that fails an expense expensive version later.
So you can do a rough sketch if you have more questions you can visit our website you'll see listed on the screen and put your comments below let us know what you think what your questions are and we'd be glad to be of assistance.