Why do drains actually block?
Drains and sewers may become blocked for a variety of reasons. As they are continually conveying waste and draining it away, it is very easy for them to become blocked. If you notice that the water is not draining away properly after you have had a bath or when you empty a sink it is imperative that you take immediate action as it might mean that the drain already has a partial blockage. It is for this reason that they should be regularly checked and maintained by an expert.