Water in CrawlSpace
I went to great lengths to get the footing drains correctly placed around my perimeter foundation(working with an experienced excavation contractor) but with even the first rains of the season I’m getting water under the footers and into the crawl on the wet(uphill) side of the building.
One problem is that I do not have gutters on the building yet, and its a shed roof emptying to that same problem side of building. I am doing my best to manage this bulk water with tarps before I get gutters installed but inevitably some is making its way near the foundation.
My question is why the footing drain is not doing its job? It was laid right at the bottom of the footer on level ground with holes down. I did lift the pipe just very slightly on the up hill side of building to give the pipe a very slight pitch toward daylight, so it might be 1-2 inches above the very bottom of the footer in the problem location. I’m wondering if this is enough to allow water to flow underneath the drain? my understanding when I installed it was that water would hit the footer and rise until it reaching the drain, then be taken to daylight. I can clearly see that is not working.
One thing the excavation contractor did that I question is leave a lot of gravel fill exposed all the way to the top. So its essentially acting like a big rain catch, it does not have the impermeable “cap” of clay I see in the diagrams.
I think the next course of action may be to dig a primary curtain drain ditch on the wet side of the building to take bulk water away before it gets to the foundation. I would dig this trench just a bit deeper than the bottom of the footer. Soils are of high clay content.
I am pretty surprised after all the work and planning that the drain is working so poorly.
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