The freeze and thaw cycles of our Ontario climate can wreck hazard on our properties, especially when extreme weather systems, due to climate change, bring more snow and water than our drainage systems can handle. Is your property prepared to handle it? Ask yourself these five essential questions and learn how to reduce storm water damage.
Did you know that since 1948, the average annual temperature in Canada has warmed by 1.6°C, a higher rate of warming than in most other regions of the world? The federal government predicts that we will be at higher risk of extreme weather events such as heat waves, heavy rainfalls and related flooding, dry spells or droughts, and forest fires.
Municipalities in Ontario, as well as other municipalities across Canada, are working to address the problem by implementing ways to deal with rain water and melting snow, which is called “storm water,” as well as how to conserve water use. They are grading roads to withstand large amounts of water accumulation and upgrading sewers and water treatment plants in anticipation of increasing needs. As well, they have implemented new by-laws for water conservation. They want homeowners to check the slope or grade of their properties, and to assess it from time to time, to make sure water continues to drain away from house foundations and neighbouring lots.
It’s important to think about storm water collection and water conservation when you are installing a new garden or trying to improve an existing one. Start by asking yourself the following questions:
Question 1: After heavy rain, are there areas on my site where water collects? If so, how can we modify the landscape to safely dissipate it and move it away from the house or neighbour’s property?
Nowadays, homeowners want gardens with lots of paving; to incorporate a variety of items such as: fire pits, swimming pools, outdoor kitchens, outdoor dining rooms and more. What may not be evident, is that with more so much “hardscape,” flooding can be a problem. This is because th
e water doesn’t have anywhere to go if the surface is not impervious to water. Therefore, it’s important to design and install paved areas with water management in mind. To protect your landscape investment and avoid potential flood damage, plan for incorporation of dry wells, French drains and swales–which are a shallow, trough-like depression that carries water, to manage the water flow that’s anticipated. Swales are a good way to channel excess water and lead it into safe collection areas such as French drains or dry wells. A good landscape designer, together with a competent and experienced landscape contractor, should be aware of the need to manage storm water and advise you accordingly. However, be sure to ask what the storm water management plan is and what it involves.
Question 2: Are paved surfaces able to absorb the collection of the water? If not, what can I do to address this problem?
Even if paved surfaces are installed correctly, with the correct slope, the problem with most common hardscape paving materials is that they are not pervious; they do not allow water to permeate through into the ground. So, the more concrete or man-made sidewalks or patios we incorporate onto our property, the more potential problems we can expect with storm water. And as storms get harsher and harsher due to climate change, the problem is bound to get worse. One solution is to use permeable pavers, which are new to the marketplace. Techno-Bloc, a Quebec-based manufacturer, and Unilock are both companies that have introduced permeable pavers in their 2017 product lines. to address this problem. There are many benefits to using “permeable pavers” if they are installed properly; easier installation and prevention of problems due to storm water collection, which is ultimately a money saver for homeowners.
Another solution is to reduce or eliminate non-porous paved surfaces all together. Replace them with porous materials such as wood chips, gravel, or other porous paver stones. Colourful aggregate materials are a hot new trend that is getting
more and more popular; they are both decorative and functional. Such materials more easily allow water to seep through the ground and naturally dissipate rather than creating a “river” or “pool” that eventually floods your property.
Question 3: If there are bare spots on the property, how can we prevent soil runoff and soil erosion in that area?
Often soil particles are carried by runoff, water that doesn’t soak into the ground, but flows over the surface and runs to another area. Planting ground covers on slopes or bare areas helps control erosion and runoff because plant roots hold the soil in place, and the leaves protect the soil from the impact of raindrops, reducing soil compaction, and improving the speed with which water soaks into the ground. Ground covers can produce attractive patterns with variations in height, texture, and color. They also conserve soil moisture; reduce maintenance in narrow or odd-shaped areas where mowing, edging, and watering might be difficult; reduce heat, glare, noise, and dust; and block foot traffic without blocking the view.
Question 4: Is it possible to plant a rain garden to collect rainwater and hold it until it slowly soaks into the ground?
A rain garden is a shallow depression that’s planted with deep-rooted native plants and grasses. It’s positioned close to a run-off source like a downspout, sidewalk, driveway, or sump pump. It will clean water, create a habitat, and prevent local flooding and water pollution.
Question 5: How can we collect excess rainwater for re-use?
With more and more restrictions on water use, it may be worth considering rainwater harvesting — collecting and storing rain for later use. It is still used in many rural areas throughout the world, and today it is making a comeback in urban centres as an additional source of water. At the simplest, rainwater harvesting consists of a rain barrel placed under the downspout of your home to collect rainwater for garden irrigation. More sophisticated systems collect, store and distribute water to where it’s being used and can be attached to irrigation systems for watering the garden or even for household needs.
A qualified landscape designer can help you plan a garden that takes these important things into consideration.