The most damaging and stressful aspect of a landscaped yard is drainage issues. Not only is it a headache to deal with in the lawn, but poor drainage near a home's foundation can cause serious problems. The following project is a real example of how important proper drainage is for residential landscapes.
This particular homeowner contacted us with some serious drainage issues. When it rained, it literally poured. Water would rise to the bottom of their patio door and flood the basement. Sump pumps couldn't keep up. They couldn't take summer vacations out of fear that a storm would flood their home if they weren't around.
The main reason for all of the flooding was a combination of a poorly graded yard, an inefficient treatment of runoff, and a protected wetland on the property. The home shouldn't have been built with a walk-out basement because of all these issues. There simply wasn't enough slope to move water AWAY from the home. As a result, rainwater would runoff their roof and dump into the low-lying backyard. The lawn was already saturated because of the pond on property and since the backyard was the low spot of the neighborhood, water would immediately pool up with nowhere to go. Correction: there was ONE place it could go. The basement.
Before we could address the flooding onsite, we needed to survey the property for accurate elevations. If there wasn't enough slope in the yard, it would require us to use an alternate and costly solution not desired by the homeowner. Fortunately, we determined there was a two foot elevation drop from the house to the pond; giving us just enough wiggle room to get water moving on site. The four main goals of our design were:
- Protect the foundation of the home
- Regrade the yard away from the home
- Capture and redirect rain runoff
- Create a controlled collection area
Protecting the Foundation
After each rainfall or snow melt in the spring, water would backup around the house and flood the basement. Our solution to protect the walkout basement was to install a patio with LOTS of drain tile underneath. This allowed us to set a finished grade that sloped away from the house. The drain tile was used to collect water instead of letting it pool up. The homeowner also benefited by getting a nice bluestone patio to use in their backyard.
Regrade Away From the House
Even though the low spot on the homeowner's property was the pond, their wasn't sufficient slope in the yard to prevent flooding. We needed to completely regrade the lawn to take advantage of the two foot drop in elevation from the house to the pond. This would prevent pooling while the sprinklers were on and flooding during heavy rain or snow melt.
Capture & Redirect Rain Runoff
Because the house was built as a walkout basement, all the runoff from the front yard and neighbor's yards would collect in the homeowner's backyard. We needed to deal with the influx of water, especially the runoff from the roof. To do this, we installed catch basins at the bottom of every downspout and connected them to a drain tile system. The rows of drain tile extended 18 feet from the back of the house and funneled into a 6-inch drain pipe leading to the pond. This would ensure all excess water would move away from the home quickly.
Controlled Collection Area
Water can be a very tricky issue to deal with. Even with proper drainage and drain tile installed in the backyard, there still was a risk of flooding from the pond. We needed a better way to control where all the water was draining to. Our solution was to dredge out a small collection area on the edge of the pond. However, the pond is a protected wetland and we'd need permission from the city and DNR to start construction. Once our design was approved, we were able to clean and dredge out our miniature retention pond. All the runoff and drain tile now drains into this depression. When it overflows, a channel allows the water to flow into the protected wetland instead of the backyard.
Once we completed the drainage aspect of the design, we re-installed the irrigation system and sod. With one of the wettest springs on record in Minnesota, the homeowner is ecstatic to report there has been zero flooding issues. It's a landscape miracle!
"The improvements that Peterson Companies made to the drainage issue we had in our backyard has been wonderful! We haven’t lived this stress free during storms since we moved into this home 7 years ago and inherited a problem we didn’t know existed." - Homeowner