Many of the older cities in the Chicagoland area have combined storm and sanitary sewers, meaning that the rain water drainage is collected through the same pipes as the sewage from houses. This type of system is almost never used anymore when constructing a new system, but many of the older cities still operate this way.
In these older cities with combined sewers it’s very common for houses to have a grease trap built in. Because the sewer system is combined, and because back when the system was built it couldn’t handle grease very well, grease traps were a way to prevent grease from entering the sewer system. Here’s a brief description of a grease trap.
A grease trap is a pit buried underground where water from the kitchen drain runs to. The exit pipe to the sewer is elevated a little bit from the bottom so that there’s always some water in the pit.
There’s a trap built over the sewer pipe, so that grease floating on the surface of the water is held back, but the water is able to run under the trap and out the sewer pipe to the sewer main. Any solid debris will settle to the bottom.
This way the grease is held back out of the sewer system. Note that only water from the kitchen flows into the grease trap. There’s no water from any other sink and certainly no water from any toilet coming into the grease trap. But there might be water from your gutters flowing into the grease trap. Where your gutter downspouts go underground they generally empty into the grease trap.
With this arrangement you’ll need to clean out the grease every so often. This used to be a much bigger issue back when we used a lot more grease in our cooking. Now you should just throw away your grease rather than putting down your kitchen sink drain. So how often you need to clean out the grease trap depends on a lot of factors, but it’s likely to be many years (probably a decade or more) before anything will need to be cleaned out. You can hire somebody to do this for you, or you can just lower a bucket on a rope to scoop out the grease and discard it.
In well over half of the grease traps I see now the trap has completely deteriorated, usually to the point where it’s completely gone. This isn’t a problem anymore and I don’t recommend that you do anything about it. There’s just no reason to. And some grease traps have been bypassed, so that the drainage from the kitchen goes directly to the sewer and doesn’t go into the grease trap at all.
These days the biggest issue with a grease trap is the condition of the ring and the lid. If the top concrete ring is damaged or the metal lid is broken then somebody could fall through. But as long as the ring and lid are in good condition then you have very little to worry about with a grease trap.
More Posts You May Find Interesting
Because the pipe that brings water into our house is buried underground we use it to as part of the grounding electrode system. This is the system that connects the neutral wires in our house
AC wire size
One of the most commonly misunderstood issues in your electrical system is what size wire and circuit breaker you need for your central air conditioner or heat pump. In this post I’ll explain the issue.
Flue Condensate Damage
When you burn natural gas perfectly you get carbon dioxide, water vapor, and heat. Here’s the chemical equation: Of course few chemical reactions are perfect, and because we’re using air instead of pure oxygen and
A double tap is when two or more wires are attached to a single circuit breaker. In most cases this isn’t allowed, because the circuit breaker is designed to accept only one wire. So if
How long does a home inspection take?
How long does a home inspection take? Of course a home inspection should take however long is necessary, but there are some general guidelines for how long to expect it to take. For a typical
Problems with clothes dryer exhaust vents are very common defects found during a home inspection. I see dryer vent problems of some type on about 75% of the inspections I do. And this isn’t just