The homeowners had a beautiful inground pool installed last summer (2010) and the pool installer had suggested alleviating this water problem by using a trencher to install a drain tile 280' to swamp on the back of the property. I was contacted and showed up a year later and they still have standing water in the yard. The homeowner and I had a great conversation and I worked out an estimate for their drainage job.
I chose to use the E-Z Flow System from NDS and create a 'fish-scale' system that would drain to a main line of 4" slotted sewer pipe with a filter sock, and would include drainage vents/ports in any standing water areas, as well as possible future maintenance of the french drain system.
We hired our good friend and excellent excavator operator Jim Plesscher to excavate the trenches. We need to point out that we do not use trenchers to install our drain tile. Trenchers generally leave very loose soil in the bottom of the trench that is often not hand shoveled out by the installers and can allow the pipe to go up and down similar to a rollercoaster. The loose soil will absorb water, especially during the spring thaw and this will further cause the drain tile to move up and down even more. This up and down motion interrupts the ability of the pipe to drain and will hold large amounts of water in the pipe.
We are committed to installing our pipe on a solid base (no loose soil), whether we hand dig the trench or use an excavator to do the digging. We are also committed to excavating the trench with the proper fall which is a minimum 2" fall every 20' (the trench in the picture was draining the entire time we were excavating it). We installed drainage vents/ports to the surface every 100', as well as in any areas of standing water such as where you see the white Dodge pick-up parked in the pictures. Our systems are able to be either router-rooted or water-jetted if the need ever arises. This is done so that are systems are installed with the intent that they can drain forever!
After this system was installed, our area over the course of 36 hours received approximately 9.5 inches of rain. I visited the system to look at some additional work the client wanted done, and was extremely surprised to walk up and down the length of the area that we had excavated and backfilled for the trench, and it was extremely firm to walk on. That was an immediate indication that the french drainage system was performing perfectly. The homeowners were trying to get this area drained properly so that they could proceed with installing a rather large paver patio. As long as they used a layer of GeoTextile and built the base material out of rock, they had my blessing to proceed with their patio installation plans.
I would have to say that this french drain project was working better than even I had anticipated...I expected due to the composition of the clay soil for the drainage of the area to be a little slower. Although, I can't argure with the smell of victory over another homeowners drainage dilemma!
Thank you and STAY DRY!!!