We’ve just had some heavy rains in the Twin Cities, and from the weather forecast there’s more to come this week.  Some areas have flood warnings, so if you’re near water, keep an eye out.

There’s no avoiding spring rain in Minnesota, but when it comes so soon after the ground as thawed, it can cause damage, from plant loss to interior water damage.   This can happen even if you’re not near a river or lake, because excess water is hard for thawing ground to absorb.  We’ve found that the most effective way to handle this problem is through proper landscaping.

Why Landscaping Matters
The main cause of basement flooding is improperly graded yards. Land has natural peaks and valleys, but when builders work on a house, the yard can end up with the wrong grade. If the land slants towards the house, water naturally drains to it. If there are dips in the land, this encourages water to collect, and eventually spill into the foundation. Once water gets inside, floor boards will warp, appliances will warp, and mold and mildew will grow.

Rerouting Water
Before you start digging, take a look at your gutters and downspouts. If they’re not functioning properly, water can be coming off the roof and landing right by the building’s foundations. An easy way to remedy this problem is to install sloped leaders to the gutters and set them to lead water at least 10 feet away from the home.

You can also alter your downspouts so they empty into an either above or below ground basin to be used later. Rain barrels are also a great option.

Regrading
If your gutters and downspouts are alright, then it’s time to fix the yard’s grade. If there are too many low points in your yard, regrade for one inch per every five square feet of land.

Another option includes exterior perimeter drains, which can be either surface or subsurface. If your soil is mostly clay, the surface option is best for you, while soil which is primarily sand or silt works better with subsurface drainage.

While you may be able to correct smaller flooding issues, if they’re too severe, it’s time to call a professional in. The expense of having someone else fix the problem is minimal when compared to the cost of repairing water damage.

If you notice areas of standing water from the recent rains, even after the rest of your yard has dried up, you may want to arrange for an on-site consultation to discuss drainage solutions. 

Spring is on the way, and as snow begins to melt, drainage problems may make themselves evident. One of the simplest ways to correct the issue is through installing a French drain.   This type of drainage system is one of the simplest options, won’t impact your landscape design and can be done by some homeowners, although for large and complex areas it may be best to hire a professional landscape excavator.

Installation

The Trench:   The first step is to dig a trench. In most cases, it should be between 8 and 12 inches deep and 5 or 6 inches wide.

Grade:   In order for water to flow correctly and in the right direction, the slope needs to be at least .5 percent. However, 1 or 2 percent is better in most cases.

Gravel:   Fill the trench with .5 to 1 inch size gravel. There should be a few inches between the top of the gravel and the surface.

Sand:   Spread three to four inches of course sand over the gravel. This provides turf a place to take root while allowing proper water drainage.

Turf:   Lastly, you can either add seeds to the sand, or allow naturally spreading turf to fill in the gap. If you plan on using sod on the the area, wash the roots to get rid of fine soil. This will prevent the sand from being contaminated.

Adding Drain Pipe

In some cases, you may want to add a drain pipe to the trench. Usually, four to six inch pipes are installed in these types of trenches.  To install the pipe, add an inch or two of gravel, set the pipe on it and surround it with gravel.

The pipe should be perforated and wrapped in protective filter fabric. It should also be surrounded by at least an inch of gravel on each side.

Complex Systems

If you need multiple drainage lines, it’s best to get a professional involved who is experienced in landscape excavation. If your property needs multiple grades, it’s essential to have the right pipe sizes and measurements for proper drainage.

Although water damage on your property can be difficult to repair, the best way to deal with it is to prevent it through such drainage solutions as this.  There are a variety of other solutions available as well – talk to a professional landscape designer experienced in water management.