Driveway Drainage Problems
Trench drain has many residential, commercial, industrial and transportation applications. The most common question I receive from home owners (residential) deal with driveway drainage problems. (I had this question today, so I’m writing about it, now.)
(Q) When a driveway slopes down from the road toward the house, there is the propensity for rain water to flow into the garage and lower house during heavy down pours. How can this be corrected?
(A) Any drain system installed in the driveway will help. However, you need to know how much run-off water to expect on a heavy down pour. A simple 12″x12″ square drain might be adequate. However, watch out for the clogging of small drains by leaves and trash which will put your garage and basement ”back in the drink”.
If you are going to install a drain in an existing driveway, I recommend putting in a trench drain. You will need to cut and patch the concrete or asphalt driveway no matter which system you use. There will be more cutting and patching with the trench system. However, with the trench drain system, you will receive far more drainage for the amount of work applied to the project.
Again, the size of the trench drain will depend on the driveway dimensions and anticipated rain fall. For small driveways with light automobile traffic, a 4 inch wide (inside dimension) trench drain with a Class B grate should be adequate. For longer driveways that generate scary amounts of water, use an 8 inch wide trench with a cast iron grate. Make the length of the drain 80% - 100% the width of the drive.
You are going to need to drain the rain water away from the trench drain, as well. To do this, you will have to dig a trench in your yard and place a drain pipe from the drain system to the nearest storm sewer or hillside. Use the flexible perforated 4″ diameter black pipe that is commonly used in french drains. Be sure to place coarse gravel around the drain pipe so that you don’t fill the perforations with dirt. This drain pipe will help keep your yard drier, as well.
Michael
I need a 8-10′ trench drain for my pole shed for when I wash vehicles, etc.
The concrete floor will be 5 ” thick.
There will be skid loaders and trailers and some 1 ton trucks driving over it sometimes. What kind of trench drain do you recommend?
Bob,
Most trench drain systems are designed as “concrete forms”. As such, their primary function is to hold wet concrete in place until it cures. The cured concrete then becomes the load bearing member of the structure. This is why most trench drain system manufacturers recommend at least 4″ of concrete surrounding them.
Riverside Steel manufactures an all steel trench drain system for residential applications called E-Z Drain. The preferred installation method for this product is to surround the system in concrete, but the all steel construction will, by it self, support slow speed auto traffic. I would definitely not recommend the use of any of the plastic or composite products on the market, as they would crush under the load.
My only other concern with an install in gravel is movement of the system in the gravel. Gravel is not a very stable medium. It tends to shift and sink over time. Unless the system could be firmly anchored to the sub grade I would be concerned that any lateral displacement or pitching of the system might compromise its efficiency.
Most manufacturers recommend embedding all trench drain in concrete if there is going to be more than foot traffic. I have seen situations where the base of the channel was embedded in concrete and the upper body of the channel was lined with pavers, however.
I have a sloping driveway that goes from the road down into my garage. The garage is basement level and below ground. Water enters the driveway during heavy rain storms (and also when the corner sewer overflows!). The result is a wet garage floor. I have lived with this situation 40 years, but I am now sick of it! I have a 12″ x 12″ square drain at the entrance to garage door.
I believe a trench drain will help considerably, but I can’t figure out how to drain the water out of the trench, since it will be below ground level. There is a sewer pipe fixture in my garage floor about 5′ from current 12″ drain. Can the trench drain be connected to that pipe? Thank you.
William W. Burrows