Let it drain

© Michael Blann | iStockphoto.com; rain bird

Not even weather prognosticators predicted the deluge and its damage. On July 11, 2013, the skies surrounding Toronto darkened. Then, the rain came, and came, and came. Mother Nature took no pity on Canada’s largest city. The result: highways overflowed, cars were abandoned, transit trains were stuck for hours and basements across the city flooded. More rain fell in two hours than is typical for the entire month. When the skies cleared, a new record was set for most rainfall in a single day – more than 4 inches.

While this severe storm is not typical – and could not have been predicted – climatologists believe heavy rain events in short spurts such as this one will occur more often in the future. This anecdote reveals the importance of having a good drainage system for your property to protect its value. As Toronto’s recent record rainfall illustrated, those prepared with proper drainage systems for their homes and properties made the grade and fared much better than those who did not plan for the worst-case scenario.

The area you are draining will determine the system design.

Do your homework.
National Diversified Sales (NDS) offer a tool for homeowners to help figure out which system is the right fit. NDS also offers services on how to find a contractor.

“Residential customers usually have a need that is relevant to their property and rely on the expertise of a local landscape or irrigation contractor,” says Jay Hartley, district sales manager for NDS. “Most every drainage situation will be different. Its goal is to remove water and there are not too many landscapes that are exactly alike. 

“For example, an Atrium drain should be used in a landscape bed to ensure positive flow of water where mulch or straw may clog a flat drain grate,” he says. “Use a channel drainage system in a concrete driveway that is holding water or adjacent to an athletic track next to a football field. Catch Basins or ‘area drains’ could be used under down spouts of a building or house as well as turf areas that are holding water.”

According to Dave Polisky, director of product marketing for Flex-Drain, equally as important as ensuring proper drainage in your customer’s yard is deciding where to send that water when it’s being diverted. There are two places that are absolutely off limits for receiving drain water: someone else’s property and any place near the foundation. Other than that, there is a lot of freedom as to where to place the drain system receptacles. Flex-Drain offers how-to videos on its website, along with other resources for contractors.

“We designed a system that caters to that tight space to allow for easier installation,” Polisky says. “The drain pipe is not the most expensive piece of a person’s landscape and the last thing you want to do is kill a 100-year-old tree with a $10 piece of pipe.”

Tools of the trade.
Drainage work begins with the right tools. Hartley says he recommends using a transom first to determine the elevations in order to design the drainage path. Then, make sure to place this information on your plan. “A lot of contractors don’t think a plan is needed and they just start digging and placing product in the ground,” he says. 

“Be prepared and have a game plan on how the installation will take place. Depending on the size of the area to drain and the location, shovels or a trencher can be used. If the system is large enough, you can also use a small backhoe.” 

If you are a contractor looking to add drainage services to your business, Polisky says buying a professional ditch digger is the way to go. “It makes a much cleaner trench and it’s also easier to back fill and patch the grass once the drainage is installed.”

For those thinking about adding drainage services, Hartley offers advice how to integrate it into a business.

“Drainage is not an easy service to add but can be a very rewarding and profitable addition to your services,” he says.

“Do your homework and understand how drainage works first. Most landscape and irrigation distributors can help you design your drainage system. Find out the amount of area you will be draining and design a system. Knowing the area you will be draining will allow you to effectively design your drainage systems.”

The design phase of a drainage project is crucial; this is where the science comes in. “Most drainage systems are gravity-fed,” Polisky says. “It’s not as simple as putting a pipe in the ground. You need to really understand gravity and how it works, and that gravity is required to move water from one location to another.”

When it comes to determining the right solution, use the following formula: Q=CIA. In this formula, Q equals flow (gallons per minute), C is a co-efficient, I equals the intensity of the rainfall – how many inches per minute or per hour. Finally, A is the area or square-footage. Use this formula to size your pipes, your grades and your basins. L&L

 
The author is a freelance writer based in Toronto.