Sewer Blockage and Clogged Drain
Sewer Blockage and Clogged Drain
Sewer Blockage/Clogged Drain

Sewer blockages and clogged drains in South Eastern Massachusetts and areas of Rhode Island often contain a mainline sewer trap. This trap can make clearing a sewer blockage difficult. Understanding how the drain or sewer becomes clogged or slow to drain is key to avoiding costly, inconvenient, and destructive sewer issues that carry a risk to the health of the occupants in the building. Many times, there is no access to these traps. The picture above demonstrates the proper installation and clearing of a mainline sewer trap. However, if the cleanout risers are too deep, chances of getting a cable to move to the downstream side of the trap are slim. (notice the cable being inserted at an angle. This is difficult to do if the trap is set too deep into the ground.) It may be possible to move a cable through the trap from upstream. However, the cable tends to navigate from upstream, down to the bend of the trap, and then straight up to the cleanout plug. So, proper access and installation are crucial to clearing a sewer line if there is a mainline trap installed on the sewer.

The most common way for a sink drain or branch line to develop a blockage is by misuse. Water

and liquid should be the only elements to pass the strainer and enter the drain line. However, garbage disposers offer conveniences we take advantage of.

When a garbage disposer is in use, it should be operated with plenty of water and moderate waste. That seems obvious. However, many people operate garbage disposers simply believing, that since they no longer see the debris, the disposer has thoroughly done the job. The power switch and water are shut off and there sits a fine blend of organic sludge, waiting for the next use of the disposer.

Bathroom sink and tub blockages develop from a plethora of chemical compounds of different consistencies. Mouthwash, toothpaste, soaps, lotions, shaving cream, oils,…etc. all contribute to clogged drains in our bathroom drain line, or branch line. The branch lines are what allow gray water to flow to the sewer. However, the sewer line from the bathroom group which includes the toilet is also impacted by what flows from the tub and sink drain.

The material a sewer line or drain is comprised of must also be taken into consideration when we estimate what contributes to sewer and drain line failure. Cast iron and galvanized steel pipe rot from the inside out. Galvanic erosion also takes place when the sewer and drain line consists of dissimilar metals, such as copper drain lines joined to cast iron sewer lines. The electrolysis between the two metals helps build scale and iron oxide deposits, where debris lodges and builds restriction.

Scale and iron deposits form in steel and iron sewer systems, pitting the pipe. This allows for pockets of particulate matter to lodge and begin building “sewer sludge”. The sewer sludge begins to build and over time, the inside diameter of the pipe is restricted.

Restriction of the sewer and drain lines is in essence a clog. Sewage and grey water flow slower. The lines were originally installed with consideration to size and gallons per minute the drain lines would need to convey the sewage to the sewer. Though water is flowing, you will notice it does not leave the tub or sink basin as quickly as it used too. This should be taken as a precursor to a blockage.

Finally, the main sewer line blockage. The main line fails in the same way the plumbing group drain does but, on a larger scale. Buildup in the main sewer line is often referred to as “grease” by sewer and drain cleaners. When grease buildup consumes the sewer line, the sewer cleaning technician may offer ‘hydro-scrubbing’ in place of cabling the line to clear the blockage and restore the sewer line to optimum performance.

The main sewer line often suffer from sludge and grease. However, there is another foe that prevails more often. That is “root intrusion”.

Root intrusion can devastate a sewer line. The roots begin infiltrating the sewer line through failed seals in the line. This type of pipe is known as “gasket pipe”. The gasket or seal in the main lines is wrought from years of submersion in water and various chemicals. Once the seal fails, sewage leaks into the soil and offers a nutrient-rich water source for surrounding vegetation. Once the vegetation begins to infiltrate the sewer line by sending out the feeler roots, the roots grow larger and stronger over time. This is where serious trouble begins. The roots begin to force their way into the line. Pressing their way into an opening causing the pipe segments to spread or crack. Given enough time, the sewer line breaks or collapses, allowing dirt and debris into the line and most certainly results in line rehabilitation or excavation to repair or replace the entire line.

In summary, this article implies an understanding of what must be done to protect our drain and sewer lines. To gain a deeper knowledge of sewer and drain line maintenance, see “Sewer and Drain Maintenance”.

Diagnosing and fixing the drainage problem for a sink, shower or bathtub may be a long and difficult process. Be safe. If fixing the issue is risky or not being understood, contact a drain service company. The range of pricing for a company that cares to do the job correctly is within $145.00 – $225.00. Sewer cleaning service may be priced between $245 and $365. This depends on material used in piping, age of the house which would help the plumber understand the plumbing code that was used in assembling the plumbing system, access to the plumbing and what is assumed to be creating the blockage.