Do Rain Gardens Actually Work? Why They’re Changing Vancouver

DATE
February 27, 2021
CATEGORY

Rain gardens – a relatively recent innovation that have seen a sharp rise in popularity amongst Canadian homeowners, stratas, and even municipalities.

They provide an aesthetically pleasing and functional means of managing rainwater runoff in cities. Even better, they’re trendy, sustainable, eco-friendly, and they can be built virtually anywhere.

  

 

Welcome to Raincouver! A Region Perfect for Rain Gardens

Okay. So you live in Vancouver – AKA “Raincouver.” Despite its mild temperatures, Vancouver is the 4th rainiest city in Canada.

It rains 161 days per year, during which the Metro Vancouver area generally sees a minimum of 46 inches of rainfall on average. In more extreme cases, some particularly rainy areas of Vancouver (such as North Vancouver) can see up to a whopping 97.5 inches per year.

Heavy rainfall in large cities presents significant challenges for urban planners and utility providers. For starters, all that rain has to go somewhere.

It can’t simply sit forever in the city – it has to be directed through storm drains back into oceans, lakes, or watersheds. Moreover, when rainfall hits rooftops, gutters, sidewalks, roads, driveways, and any other common urban hardscapes, it becomes polluted with dirt and contaminants.

This means it needs to be filtered and remediated before it can re-enter reservoirs and watersheds.

In other words: rainwater, when left unchecked, can cause irreversible economic and environmental damage. To help solve this, infrastructural solutions (like proper storm drains and drainage) must be put into place at a municipal level.

However, there’s an easy way for homeowners and stratas to help. By introducing rain gardens into their landscapes.

 

What are Rain Gardens?

If you live in a rainy city like Vancouver, you’ve likely heard the phrase “rain garden” before, but aren’t entirely sure what it means. Simply put, a properly designed and installed rain garden is a gently sloped channel filled with soil, rocks/boulders, and plants.

It operates under the principlesRain garden with swale of “bioretention,” which refers to the capacity for a landscape to effectively retain, use, and filter excess rainwater. In other words, rain gardens are a simple way to help manage a complex problem.

They were first introduced in the United States in the early 1990’s as a means of managing stormwater runoff and pollution in rainy urban centres.

In recent years, rain gardens have seen a surge in popularity alongside eco-friendly trends like permaculture and sustainable gardening. Now, more than ever, citizens and governing entities in progressive cities like Vancouver are pushing harder for viable long-term solutions to difficult questions. For example:

  • How can I create a garden that conserves water?
  • What can I do to build a low maintenance garden that still looks great?
  • How can my landscaping decrease my ecological footprint?

If you’ve ever asked yourself one (or all) of these questions, a rain garden might be the perfect thing to consider installing at your residence

 

What Should You Include When Building a Rain Garden?

An effective rain garden should be installed with the following goals in mind:

 

  • To use native plants whenever possible

A native plant has thrived here for a reason! Certain plants are naturally thirstier than others of a similar size, and they can handle much heavier rainfall than non-native plants that were brought here from drier climates.

 

  • To filter water

Think of a rain garden like a biological sponge. In urban areas, rainwater runoff  becomes polluted when it touches dirty roofs, gutters, parking lots, driveways, and walkways. The soil and plants in a rain garden can hold and remediate water before it enters storm drains and watersheds.

 

  • To use swales and berms to control the flow of water

An effective rain garden uses gravity to its own advantage! A swale is a sunken area, often dug to resemble a sloping river or reservoir, in which stormwater runoff can be collected and/or directed toward plants and drains by way of slopes, berms, boulders, and river rocks.

 

The Benefits of Rain Gardens

Rain gardens…

  • Are low maintenance
  • Filter runoff pollutants
  • Mitigate flooding
  • Decrease your carbon footprint
  • Clean and conserve water
  • Create habitats for important animals and pollinators (bees, butterflies, hummingbirds, and more)
  • Are environmentally sustainable
  • Replenish local groundwater
  • Protect rivers and streams
  • Remove standing water in yards
  • Reduce garden maintenance
  • Look amazing

 

Examples of Our Past Rain Garden Projects

Perenseff Residence

This East Vancouver rain garden began as a sloped lawn. Though the lawn was healthy, it offered little to the existing landscape in terms of environmental functionality or curb appeal, so the homeowner decided to have it converted into a rain garden!

For this rain garden, we took advantage of the natural slope of the lawn, creating a deep, gently-curving bioswale running beneath the existing pathways to control the flow of water. River rocks increased the river’s capacity to carry rainwater, and large basalt boulders were included as functional accents to the landscape.

Moreover, this rain garden makes extensive use of many native plants that can absorb lots of water. This effectively creates a low-maintenance, eco-friendly, and great looking landscape capable of handling heavy runoff.

Rain garden

 

BC Landscape and Nursery Association (BCLNA) Office

We built this large-scale Langley project on a south-facing garden bed that borders a very busy street. During the fall, winter, and spring this area receives above-average levels of rainfall; during the summer, however, vehicle traffic and unimpeded sunlight can make it extremely warm.

The solution? A rain garden filled with hundreds of varied sun-tolerant plants that are nonetheless capable of handling lots of water.

Because of the sheer size of this project and the amount of different plants installed along the bioswale, this rain garden is capable of ample water absorption and remediation, creating a trendy, vibrant, and beautiful oasis in an otherwise drab urban centre.

 

 

Thinking of making a rain garden?

If you’re thinking of introducing a rain garden into the landscaping of your house, condo, or strata, let us help you out! Para Space is continually seeking ways to improve your landscape in ways that make your home more beautiful and valuable. A rain garden creates and opportunity for you to become a meaningful, eco-friendly contributor to the gorgeous (but rainy!) city in which we live.

Contact us for a free quote or if you’d like more information!

 

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