When you own a home you are responsible for all of the maintenance for it. This is not limited to the roof, windows and the state of the interiors; the sewer systems and drains located on your property are also your responsibility. If in any doubt about who must maintain and repair drains and sewers and the boundaries get in touch with your local water authority who will advise which fall under their jurisdiction and which belong to your property.
It is the responsibility of every home-owner to make sure that the drainage system of the property is working fine. If the drains are not maintained then it may cause over flowing of water, and also make situations worse during the floods. A poor drainage system may cause water to stand and many other damages as well.