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Using perforated pipe to reduce hydrostatic pressure on new stone wall – GreenBuildingAdvisor
- September 7, 2025
- Posted by: sherwin@eyeconz.com
- Category: Uncategorized
Adding a new 21″ H fieldstone wall at the bottom of our front yard incline that’s about 3ft high. New concrete footing is 30″ deep. Wall is about 30 ft long. Options given were:
a) Leave as is due to very sandy, quick-draining nature of the soil. Use gravel only below the level of the sidewalk;
b) Behind the wall, use 2″ pvc weep holes recessed a few inches so pvc is not visible with filter fabric and gravel;
c) Install 4″ perforated pipe behind the wall draining out 3″ above the driveway at the end of the wall run. Contractor has stated that pitching the pipe 1/8″ per foot as per drain lines won’t work here, that a pool of water will collect below the 3″ driveway port, that weepholes would be the only option, but feels they are unnecessary due to sandy nature of soil.
So my thought is suppose the water exits just an inch or so –instead of three inches–above the driveway? As far as water collecting below a certain point, won’t more water collect if there’s no perforated pipe?