RAIN Home Visit Series Post 3: Downspout outlets
This is the third post in the RAIN Home Visit Series. This post will pick up where the last post left off. Once eaves and downspouts are effectively draining water off your roof it is time to consider what is happening to the water once it exits your downspouts.
That question of when it rains – where does the water go? is still relevant. If during the walk around your property you notice any downspouts empty into an underground pipe chances are it is connected directly into the municipal storm sewer. Connected downspouts increase the risk of structural damage because they drain water directly next to your foundation. Most of these systems are decades old and likely cracked and leaking. This is no longer a recommended engineering practice, yet many downspouts remain connected.
For the City of Hamilton’s stance on downspout disconnection see the following link:
For instructions and advice on how to disconnect downspouts see the following link from the City of Bremerton, Washington:
Once all downspouts are disconnected it is time to look at your property more closely. The path water travels along the ground will have everything to do with the way your property is graded and landscaped. During that walk around your property take note of all slopes and low spots on your property. If your property is sloping towards your house, this must be corrected to ensure water always runs away from the foundation. Take note also of the hard surfaces (patios, walkways) and soft surfaces (garden beds, lawns). Downspouts should empty onto soft surfaces a minimum of 8-10 feet and downhill from the foundation.
The City of Hamilton has issued a Homeowners Guide to Lot Grading & Drainage document which provides the basics of proper lot grading. This document does, however, lists the street as an acceptable outlet for rainwater. The next post in this series titled ‘From Rainwater to Stormwater’ will explain why sending rainwater to the street is no longer recommended best practice. The RAIN Home Visit program is all about keeping water on your property and allowing it to soak into the ground naturally where it will pose no threat to the foundation.
The safest starting point is directing water a minimum of 8-10 feet and downhill from the foundation. When directing downspouts always keep distance and direction in mind, both are just as important as the other.
In post number five of this series we will discuss more specifically where and how to keep water on your property so that it can soak into the ground before it goes from rainwater to stormwater.