Perimeter Drains

Inspection, Cleaning and Repair of Perimeter Drains in Victoria


Perimeter drains are an arrangement of piping found at the footing of your foundation wall to redirect groundwater away from your building. This keeps the water table from rising and causing flooding in the basement or crawl spaces. In modern systems, it is generally made up of perforated plastic PVC pipes. Systems more than 20 years old are usually ABS plastic or “big 0“. Older installations are generally cement or clay tile. The perimeter drains in Victoria and on the Island are generally covered with gravel or rock to let water in and protect, with landscape cloth to keep silt out.

Perimeter drains are recommended to be installed 15 cm to 20 cm (6” to 8”) below the floor level of the basement or crawl space, although in most older systems they are usually just below the floor elevation. In some cases, systems are found to be installed at or above the interior floor elevation, rendering them useless for protecting the interior from water entry. The pipeworks should make a complete circuit of the building and then go out to the ditch or the storm drain main in the street, or to some type of recharge pit that disperses the water (see Environmental Solutions).

Older installations on the West Coast are usually dual-acting systems where roof downspouts are also connected to the perimeter drain that takes the rain water along with any groundwater out to the exit point.

Modern installations are two-pipe systems where the perforated perimeter drain is supplemented with a separate tight pipe. It's installed in a shallow system and connects to all the downspouts that then direct roof water away from the foundation, by connecting to the storm lateral and out to the exit point. We recommend that these modern plastic pipe systems have a perimeter drain inspection every five years.

Perimeter Drain Inspection

We recommend that the modern plastic pipe systems have a perimeter drain inspection every five years. This can generally be done by camera first since there should be good access. A video camera is usually pushed through the pipes to get a good view of the system and any problems. If required, the system can be cleaned with specialized equipment.

Older perimeter systems that use sectional concrete or clay tile do not usually have good enough access to allow for a productive camera inspection.

Perimeter Drain Cleaning

On older tile systems, we recommend using cleaning equipment that is appropriate to the pipe work first. If the system has not been maintained, the camera view is usually poor, as built up debris and silt will block the camera lens. In most cases these older systems don’t have access that allows for an effective camera inspection. If in cleaning a problem is encountered, an access point can be exposed and the camera can view the problem to resolve it. Usually some kind of perimeter drain repair is required.

Perimeter Drain Repair

Any type of pipe or tile system can be repaired or restored back to a satisfactory perimeter drain system for ground water protection that will function as originally designed. If a problem is located during the inspection or cleaning process, you could require some kind of perimeter drain repair. This could involve anything from exposing the site of the problem and replacing a couple of broken tiles, repairing some pipes and fittings or something more extensive as replacement of an outlet lateral or an upgrade to the system.

Perimeter Drain Upgrade

After an inspection, the results may indicate a possible perimeter drain upgrade is needed. This might be from breakage in pipe work, incorrect original installation or where signs of serious erosion are found on clay or concrete tiles. Any type of pipe or tile system can be repaired or restored back to a satisfactory perimeter drain system for ground water protection that will function as originally designed. A common upgrade is the installation of a new shallow roof water system, thus separating roof water from perimeter ground water.

Perimeter Drain Replacement

Upgrading to a modern two-pipe system will usually involve the exposing of your foundation walls down to the footings, the removal of the existing system and the installation of a new deep PVC perforated pipe ground water system along with a separate shallower roof water system. As the foundation wall would have to be exposed for perimeter drain replacement, it should be carefully inspected, repaired where necessary and protected with a waterproof membrane.

After installation of a perimeter drain system on a new house or after cleaning, repair, upgrade or replacement of the water control system, the investment needs to be protected with a perimeter drain preventative maintenance program.

Perimeter Drain Preventative Maintenance

After installation of a perimeter drain system on a new house or after cleaning, repair, upgrade or replacement, our technician will be able to advise you of the recommended schedule for inspections and cleaning appropriate to your system and you will automatically receive a call-back reminder.

Don’t wait to install or repair perimeter drains for your Victoria, Vancouver Island or Gulf Islands home. Call us at 250-479-0195 to get started.