Drainage Tile Requirements

Tile Drains

• Subsurface drainage systems are a significant part of many types of site developments. Drainage pipes used to be sections of concrete or clay, called tiles. Since the 1970s, perforated pipe is the dominant drainage pipe, though it's still referred to as tile. Agricultural and urban residential developments incorporate drainage tile systems. Agricultural drainage tile systems are installed to improve the productivity of farmland, and urban houses need drainage tile to keep foundations dry.

Foundation Drains

• Water leaking through cracks, seeping under the foundation or collecting at the seam between the foundation and the wall causes mold and wet basements and weakens the structure. Building codes require a perforated pipe to be laid on a washed gravel base below the basement floor. The pipe is covered with several inches of the same gravel. No silts or fine material should be mixed with the gravel. The pipe may be encased in a geotextile sock to keep fine material from clogging the perforations.

Agricultural Tile Drainage

• Agricultural tile drain systems are buried 3 to 6 feet below the soil surface to lower the water table in areas with wet conditions. Modern drainage tile systems are well marked and mapped, but this hasn't always been the case. Agricultural developments share drainage systems. They are installed and may be maintained by the local authority, with each landowner paying costs for their share of the work. Each landowner must keep the drainage easement on their property clear of structures and debris that could block the drain.

Updating Tile Drainage

• Extreme weather events stress urban municipal drain systems, putting pressure on older structures in particular. Subsidies may be offered to help urban homeowners disconnect foundation drains from the municipal storm sewer system as a measure to protect their own basements from flooding from an overtaxed system. Agricultural communities can join together to apply for a shared municipal drain to replace older ones installed and maintained under outdated regulations by private landowners.