Collect rainwater that causes leaking into basements and crawlspaces
The winter rains in Oregon have started. The words hand excavated french drains are again in everyones conversation. Hand excavated french drains are your best opportunity to collect groundwater.
The phones are ringing. Homeowners are discovering or re-discovering their groundwater/rainwater drainage issues. Out of site, out of mind as they say. When the rains come however, nobody is immune to the problems caused by rain created groundwater.
Once the area next to your foundation is saturated it is a self fullfilling prophecy that water will be present to pump. That doesn’t mean that water was below grade water prior to the rainwater saturation.Some professed drainage contractors will try to convince you to machine excavate deep because there is evidence of groundwater coming in at that level. Usually at the foundation footing level. Most always those areas were not leaking prior to the rains saturating and causing hydrostatic pressure leaking. Improper construction of a footing drain will cause worse groundwater drainage problems and store groundwater on the foundation footing area. Collect and vent the rainwater when it rains, prior to saturation. Most of the groundwater is suspended within the top 18″ of the soil as saturation set in. Install your hand excavated french drains approximately 18″-24″ from the foundation footing area for the best results.
Get the drainage work completed prior to the saturation and there likely will be no water to pump. Sump pumps, are, in most cases, the tail wagging the dog. Pretty much like the little dutch boy with his thumb in the dyke. Plus you always have water to pump because you are not collecting it on the surface areas, and therefore not reducing the hydrostatic pressure.
Cutting off the water near the surface removes the weight of the water from below the ground surface and subsequently from the lower areas. This slowly stops the leaking even when saturation has already occured. Never go with the idea that some advance calling for placing rock against the foundation, unless it is part of a properly constructed footing drain with a below grade slope and vent system, and no other alternative exists. Most drainage contractors that say they construct footing drains do not construct them properly. Most of the time they are not needed if hand excavated french drains can be installed, and the grade improved. A properly constructed hand excavated french drain system will usually make the sump pump shut off and make it useless. Consult this blog for information on footing drains, hand excavated french drains, and the science of groundwater abatement and removal.