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Septic Tank FAQs

Septic Tank FAQs

How can I find my septic tank?

If you are not in emergency mode you can reach out to your local health department and request the location of your septic tank. Your local health department should have this information on record. Unfortunately, most people are only in search of the tank when they are in emergency mode and can’t wait for the health department.

First, try to locate where the main sewer exits the building structure. If you locate this exit point, go outside and take a probing rod and start probing in the general area anywhere between 5’ to 15’ from the building structure. Most tanks are only a couple of feet below the ground’s surface. If the above-mentioned options fail, you will most likely have to spend some money with a plumbing/septic contractor to locate the tank. Most plumbing/septic contractors are capable of using locating equipment to find the tank.

How often should my septic tank be pumped?

This is a great question and the answer is not the same for everyone. There are charts that take into account the capacity of the tank, the number of fixtures in the home, and the number of people living in the household. These charts are pretty good and can result in excellent guidelines to go by. Others say that having it pumped once every three years is the best rule of thumb.

The best answer that can be used for every tank is that the tank should be pumped when the top layer of scum/grease and the bottom layer of sludge/solids exceed 33% of the total liquid volume of the tank. The wastewater in every septic tank is separated into (3) three distinct layers. All heavy solids will fall to the bottom. This layer is referred to as sludge. All lighter material such as grease will float to the top. This is referred to as the scum layer. The rest of the wastewater will remain in the middle. This layer is referred to as the clear zone. When the layer of scum and sludge added together surpass 33% of the total liquid depth, it’s time to have the tank pumped. This can only be determined when a competent contractor uses a sludge judge, dipstick, or similar tool to take these measurements.

Should my septic tank always be full?

Unless the tank is being pumped by a plumbing/septic tank contractor it should always be holding wastewater. The liquid level should be at the invert (bottom) of the outlet line. If the liquid level is below this point, there is a chance that the tank itself has been compromised and is actually leaking into the ground. This should be inspected by a qualified plumbing/septic contractor. If the liquid level is above the invert of the outlet line, it is an indication of a problem with a downstream component.

Where should my septic tank be pumped from?

This is another great question. Most systems have inspection ports, 3”–4” inspection pipes protruding out of the ground at the inlet and outlet of the septic tanks. The tank should never be pumped from these ports. Why? Because the tank will never be fully evacuated this way. Some tanks are single chamber tanks and some are double chamber tanks. The only way to evacuate the tank properly is to excavate (if the lids are below ground), remove the manhole covers, and pump all contents from the tank.

If my sewer is backed up, will pumping my tank relieve the problem?

Maybe, maybe not. Some septic systems are very elaborate and have many different components, such as pump/dosing tanks, aeration tanks, trash tanks, sand filters, leaching/drain fields, etc. When a sewer line backs up, it could be a problem between the house and the septic tank, or it could be a component beyond the tank. There is no way to diagnose this without having a qualified technician at the site.