Sewers get blocked. Sewer drain cleaning is not a pleasant job but it needs no special knowledge or tools besides a set of drain rods and you can save a lot of money by doing it yourself.
You are more likely to get blocked sewer drains if you have a septic tank
Sewer Drain Cleaning-Preparation
Know Your Sewers
The best approach to sewer drain cleaning is to know where your sewer pipes are, where the septic tank or main drain is and where all your manhole covers are. The pipes usually run in straight lines and if you lift up a few man-hole covers you will be able to see the direction taken by the sewer pipes.
Make a note whether your sewer pipes are 4 inch or 6 inch diameter
Know Your Manholes
The previous owner of your house may have blocked some of your manhole covers. If he was really smart he will have concreted over them, but this is not likely. He may have laid grass over them though.
Once you know the direction your sewers take, use a garden fork to prod all along the route under any grassed areas, in case you find any hidden drain access covers.
Take the cover off each one. Look for where the drain comes into the access chamber and, more importantly, where it goes out.
This is important because when you have a blockage that access chamber will be full of sewage and you will not be able to see the sewage exit pipe.
Buy Drain Rods
Any plumbers' or builders' merchant will sell drain rods.
Measure the distances between manholes and between the last man-hole and your septic tank.
Buy enough drain rods to cover that distance plus 6 feet (The extra 6 feet makes sure you have enough drain rods that you can stand comfortably, even when the rod is at the end of the sewer drain) . Remember to buy one rod with a rubber plunger on the end (4 or 6 inches, depending on your sewer pipe diameter), and one with a steel macerator, corkscrew like tool on the end.
Buy these before you need them.
Sewer Drain Cleaning-Clearing Blockages
How Do You Know When Your Sewer Pipes Need Cleaning?
You will see water, or toilet paper bursting out of gaps around manhole covers. Toilets might make strange noises as they flush, because the water that normally stays in the toilet pan is being siphoned out. There might be a smell of sewage.
How Do You Know Where the Blockage Is?
Check all your manholes. The blockage is between the first empty access chamber and the first access chamber that is full of sewage.
How Do You Clear the Blocked Sewer Pipe?
If you are lucky you will be able to clear it from the empty access chamber. Screw the macerator (corkscrew tool) drain rod onto another plain drain rod. Always screw rods together in a clockwise direction. If you are unsure then practice screwing pipes together with the pipes laid out on the ground.
Always, always, always turn the drain rods clockwise when they are inside the sewer pipe, or they will come apart and then you will have a bigger problem.
Push the macerator into the entry pipe of the empty access chamber, uphill towards the blockage. Screw on more drain rods as necessary always turning them clockwise. As the macerator reaches the blockage you will feel the obstruction.
Keep turning the drain rods clockwise, pulling back by a foot every 20 seconds before pushing the macerator back into the blockage and turning it clockwise some more. Eventually you will see some sewage begin to flow out of the entry hole, a sign that success is imminent.
When the sewage is flowing steadily the blockage is clear. Remove the drain rods, unscrewing them only when they are out of the drain. Hold the rods in the drain to prevent them turning anticlockwise and coming apart.
Go back to the uphill access chamber, the one that was blocked. Use the drain rods in the same way, but with the rubber plunger on the end, Push them into the exit pipe from this chamber downhill, back towards where you were working earlier.
The plunger will push any remains of the blockage ahead of it. Make sure the sewer drain is totally clean before clearing up. Use a watering can or hosepipe to wash any stray sewage back into the drain at every manhole in the system
If the blockage is between the last manhole cover and your septic tank you will have to use this method.
This is where you are glad you checked where the outlet pipe was in each access chamber, because now it is at least one foot and possibly underneath three feet of sewage.
Probe with the macerator tool until you find the exit pipe from the chamber. Add drain rods as before, always screwing them clockwise.
Use the macerator tool to break up any blockage then pull it back. Hopefully the blockage will wash away and you will see the level of the sewage in the chamber going down.
Measure the distance between the manhole and your septic tank above ground. Count the drain rods as you screw them on and you will be able to work out where the blockage is.
If you use all your drain rods that you calculated were enough to reach the septic tank then the problem is in the septic tank and not the sewer pipe. This is a serious problem. Your septic tank needs emptying and probably cleaning. The drains have backed up with sewage because there is nowhere for it to go.
You will need to find a septic tank cleaning contractor, who will arrange a tanker to come to pump out the sewage from the septic tank. This is a messy job in itself and you will want to check the inside of your septic tank for pipes that have come apart, especially if you get blocked sewer drains again in the next twelve months.
Make sure you employ a licensed septic tank cleaner. Disreputable companies will just empty the tanker into a local river, killing fish and other wildlife.