How drains work – Sewer, septic and storm water drainage systems work on the principle of “gravity”. This means that the liquid and solid matter moving through the underground pipe gets to the other end by simply running down hill under its own weight on the bottom of the inside of the pipe. Depending on the location most drainage systems only have a slight or minimal down hill slope or what we call grade. For example the minimum grade for sewer lines is 1 in 60 which means a 60 metre sewer line will fall only 1 metre over that length. Considering these design factors it soon becomes obvious that for drains to operate without blocking up the inside surface of the pipe must be smooth and free of obstacles such as breaks, cracks, misaligned joints, tree root intrusions, foreign objects and other abnormalities or defects.
It is also very important that drainage systems do not leak into the environment. This is particularly true for sewer and septic systems as they convey human waste, house hold chemicals and other waste products away from the home or business to be treated. Once a drain has been compromised in one form or another it will inevitably start to leak contaminates into the environment which can make their way into our creeks, rivers and water ways and can also become a health hazard.
Over time this leaking also contributes to the ongoing demise of the whole drainage system and can cause structural damage to valuable surface structures such as drive ways, swimming pools, tennis courts, retaining walls, structural slabs and landscaping etc.
It is important to keep your drains structurally sound as any structural fault can allow tree roots a way into your pipe work. Once roots are in your pipe work they are likely to eventually cause a blockage and in the long term can completely destroy the drainage system. The best way to prevent on going blockages is to rectify the affected section of pipe work. Conventional excavation and structural pipe lining technology are the most common methods for rectifying underground drainage. You may wish to have a CCTV camera inspection of your drainage system to determine its condition and if any repairs are needed.