if you have a wet lawn that doesn't drain away or water coming into your house, you may need one of these
a french drain is a creative solution for controlling a large volume of water invisibly
Pictured above is a house with a flooded lawn. You can see that the water will seep under the house and into the home and garage. What is needed here is a French Drain to wrap around the part of the house effected by the water to divert it safely away.
A French Drain is similar to a dry creek bed, except the water flows underground through a drainpipe enclosed in a gravel-filled trench. The drain-pipe is specially designed with perforated holes to let the water enter it and be directed to your Storm-water Line or where-ever you wish it to go. The water seeps through the French Drain much faster than it would on normal land as the drainage scoria used lets great volumes of water drain through.
The French Drain in the above picture was made into an attractive footpath. Now the water will be effectively collected and diverted away from the house.
French Drains can also be disguised by laying turf over them so they can invisibly join with the rest of your lawn.