I am contemplating digging a drainage trench to drain my gutters instead of just having them empty onto my lawn. My plan is to go down 4 feet which is the frost line here and then install perforated drainage pipe which will funnel the water away from the house into small underground gravel beds. I have two questions.
(1) The soil in my area is sand. How big do I need to make the gravel beds to ensure drainage with no backups?
(2) Can I rent a small excavator to do this, or is operating those things strictly for professionals? Will I find it easy to dig a 16 inche wide, 4-foot deep trench?
Best Answer
Tyler, This can be tough to give based on area. Where I live 3" is a huge storm but we have constant rain at small amounts for months. The first system I built was a 500 cubic foot catch basin the house was under 1800 sf. the system filled at almost 2x the rate I had expected (full in February). The next year I added a 2nd cistern now watering my plants with fresh water was getting expensive. Both cisterns were completely full by March the 3rd year. There was not that much rain. what I missed in the winter the water table in my area jumps close to 6' so the over flow drains were actually back backfilling the tanks with water. My 2 over flow drains were basically shallow (2-3’) French drains 8” wide both 75’ long that drained into a seasonal creek at the bottom of the property. Depending on the water table in your area a drain field may be all you can do. I have belt rock basins (large pits to catch run off filled with rock) to catch the water and allow it to filter back into the ground instead of being run off into storm sewers. This would not work at the home in Oregon. This was meant to be a comment but is too long. I wanted to explain that it can be difficult for a DIY because there are factors we don’t think about. Good Luck.