Do Driveways Need Drainage? (Why It’s Important)

The answer to that question is a simple yes, but what are the reasons for the driveway to need drainage.  In this article, we will cover some of the reasons a driveway needs drainage. 

Some of these reasons the damage will appear quickly in the driveway while others may take months, even years before you notice the damage.

Why is Drainage Important?

If you do not have proper drainage for your driveway it can present several issues. 

Water that cannot drain can cause discoloration, excess wear of all concrete surfaces, and damage.  The water can also wash out and destabilize base materials. 

It can also get into subgrade soil levels and cause your driveway to expand and lose load-bearing capacity. 

In the time it will cause cracks and lifting base shifting.  If this type of damage occurs you will have to completely demolish and replace all the pavement that is affected.

On unpaved surfaces like your lawn, it could wash away soil, cause sogginess, and destroy plants.

The worse damage from driveways that do not drain could be the foundation of your house.  The damage could cause many problems that could be costly to repair if it can be repaired at all. 

This generally happens by DYI’s that do not know how to put in a proper drain so that is why a professional should do it.

If the water puddles on the driveway and there are cracks, some water is going into those crack and once the weather turns cold, that will freeze.

One thing to remember is that water expands when it freezes so that will create some powerful pressure under the surface.

In time, it can become a force that is strong enough to crack the concrete or asphalt.  Winter is one of the hardest seasons on the driveway.

Any snow or rain that lingers on your driveway could discolor the driveway.  On asphalt driveways, the standing water could speed up the process of fading. 

Water that pools on your driveway for a long period of time could encourage algae to grow, which can stain the surface of the driveway. 

The water puddles can contribute to excessive wear on the sealant, which will allow moisture and other contaminants to penetrate the surface of your driveway.  This can prematurely age your driveway.

If you let the water pool around the sides of your driveway it could cause the driveway’s foundation to start to erode.

The subbase layers that are supporting the top layer of your driveway can wear away. 

Your driveway may start to sink in places if this support fails.  Soon your driveway will nothing but a mess of uneven surfaces and cracks.

Types of Drains

• French drains:  This is the type of drain that you should use to drain excess water on unpaved surfaces.  This drain consists of an underground perforated pip.  There is a filtering layer on top of the pipe so that water can seep through the soil into the filtering layer.  It will ultimately go through the perforations into the pipe.  It will be laid on a sloped trench so the water is carried along.  It will help to prevent your lawn from becoming soggy.
• Trench drains:  This is used for the same reason as a French drain but the drawback is that is a budget-oriented solution so it is not as efficient.  The trench is filled with drain rock and topped off with soil and will take the water away so the ground is not as soggy.  With this one, you have no control over where you let the water go.
• Basin and channel drain:  These are used as a combination for paved surfaces, like driveways. They collect the water that is running freely on the paved surface.  They are different in size and shape.  The box drain is about a foot by a foot and is usually placed next to a retaining wall or curb and have the paved surface sloped toward it.  The channel drain is used for a bigger area to cut off the water flow.

Components of a Proper Driveway Drainage

• Gradient:  This is very important to have proper drainage for your driveway.  It is referring to how the driveway and surrounding areas slope.  When your driveway is properly graded, the water will just run off the driveway.  There are two types of gradient.  One is called the endfall, which is the slope from the beginning of your driveway to the end.  For example, if your driveway was 60 feet long, along the length of it you will need about a one-foot change in elevation.  The other is called the crossfall, which refers to the slop from one side of the driveway to the other side.  Many times driveways are lower along the sides and raised slightly in the middle.
• Rainwater runoff and drainage:  Even if your driveway slopes toward the street, it is a good idea to add on either side of the driveway a rainwater runoff.  Every so often it should have metal driveway drainage grates to make sure that it is running off correctly and into the main drainage system, you have on your property.  It is just a shallow channel that goes down the entire length of the driveway.  It can be made with cement, cobble pavers, or bricks.

Conclusion

• If you are having a new driveway installed, to help combat drainage issues, look at the slope and placement.
• The driveway should slope away from your home.
• If your home sits below street level, it is important to have the right drainage, especially if the driveway slopes down from the street towards your home.  In this instance, you could have water coming into your home.
• If you are a potential buyer, always check out the drainage system in place for the driveway to make sure it is draining correctly.
• The best concrete driveway drain would be either a trench or channel for either concrete or asphalt.
• When building a new driveway, it is advisable to leave it to the professionals as they know how to do the drainage right.