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What are downspouts?

Downspouts are the pipes that take the collected roof runoff in your eavestroughs down to the ground. When it rains, or when the snow on your roof melts, the downspout allows for the collection and drainage of your roof by allowing it to flow down to ground level. They are also referred to as “roof leaders”.

What is the problem with downspouts?

the downspout connects to the bottom of an eavestrough

Downspouts themselves aren’t the problem. They are required to properly drain the runoff from your roof. The problem can be where this water gets discharged to.

If the downspouts come down your exterior walls and enter a pipe in the ground, they are most likely going to the sanitary sewer.

Considering that a single home is able to drain quite a bit of water during an intense rainfall, imagine if many homes were doing the same thing, at the same time. This quick and sudden rush of water into the sanitary sewer can rapidly over-fill the pipes and cause sewage backups in basements. Roof runoff is relatively clean storm water which should not be directed into the sanitary sewer system. Your home may not be experiencing flooding as a result, but you may be contributing to sewage backups of a neighbour or someone even further away.

downspout illegally connecting to the sanitary sewer

Sanitary sewers are not designed for storm water, and overloading the sanitary system not only causes sewage backups into basements, but also causes bypasses of untreated sewage to the environment – your local rivers and lakes.

If not to the Sanitary Sewer, where should downspouts discharge?

In general, it is best practice to discharge your downspouts to your own lawn so that the water can naturally infiltrate into the ground. If you are unable to do that for legitimate technical or safety reasons, your next alternative is the storm sewer. Discharging to the sanitary sewer is not an acceptable alternative as you put not only your own home at risk, but also the homes of others at risk of sewage backup. You may need to touch base with the City’s Engineering Department to assist you in finding a suitable discharge location for your storm water. It’s worth noting that there is no “grand-fathering” or acceptance of older downspouts going into the sanitary sewer. Just because it used to be done that way, doesn’t mean it’s right.

downspout correctly discharging away from the building

What does the City plan to do about downspouts?

Downspouts are located on private property and generally, the maintenance, upkeep and discharge is up to the homeowner. But, discharge of downspouts to the sanitary sewer system can affect everyone, including your friends and neighbours, and the environment. For this reason, the City of Kingston has made downspout discharge to the sanitary sewer illegal, by way of By-law 2008-192 (Clause 3.11). The City will soon begin enforcing disconnection of downspouts from the sanitary system.

What should I do?

Be a good neighbour, and disconnect your downspouts. We all need to work together to reduce basement flooding!