Summer can lead to major sewer line backups in your home if you aren't careful. There are three main reasons why these seasonal backups occur, but you can take steps to avoid the problems. 

1. Drought Stress

It may seem counter-intuitive that dry conditions in the environment could cause your sewer drain to backup. However, severe drought can cause soil shrinkage, which means that the soil pulls away from the main drain line. This can then create a void between the drain pipe and the ground, which causes the pipe to shift. A shifting pipe is more likely to develop gaps or cracks that can allow soil and roots in, which will then lead to a major drain backup in the house or a sewage leak in the yard.

Pipes that are already suffering minor damage are the most likely to be affected by shifting soil. An annual drain inspection can catch damage early so they can be repaired promptly.

2. Summer Storms

Summers aren't always hot and dry. Thunderstorms and heavy rains can eventually move in and cause stress to your sewer line. The high influx of water over a short period can overwhelm municipal sewer systems and cause water to flow up your drain pipe. If any part of the backflow prevention system fails, then the raw sewage may come up into your home.

Fortunately, this issue is typically preventable if your backflow system is working properly and your drains are clean. Annual cleaning along with a test of the backflow system is all that is needed to avoid problems.

3. Root Incursion

Spring and early summer generally see the most vigorous root growth from the trees and shrubs in your yard. A tree can be several yards away from your main drain line, yet the roots can still grow densely around the pipe. These roots seek out the high moisture, high nutrient content inside the drain line. Fine root hairs invade the pipe via gaps and small cracks, where they then grow quickly and fill the line.

You don't need to get rid of your trees to prevent root incursion. Instead, plan to have the roots removed with a thorough annual drain cleaning. Your drain service will use an auger or a high-pressure jet of water to rinse out the roots. They will then prescribe a monthly root treatment that prevents new roots from invading. 

Contact a drain cleaning service in your area if you are having issues with summer drain backups.