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Water in Crawl Space

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My wife and I purchased a home 3 years ago in southern Alabama. At that time, there was no water in the crawl space.

We recently listed our house and had an accepted offer. The inspector found so much standing water under the house (in crawl space) that he would not even go under to inspect until it was dry.

We have 14 air vents and an access point that were all at or slightly below grade. (The previous owners must have built up the lot a while back). The ground level in the crawl space is about 6" lower than the exterior ground.

We assumed that rain water runoff was pouring through the vent holes, so I had a brick mason come and raise all of the vent holes and access point by two rows of brick (approximately 6") above the exterior grade.

I had a plumbing company come out and pump all of the water out. They also tested for water, drain, sewage leaks and none were found.

It stayed completely dry until yesterday. We had a rainstorm (approximately 3" of rain), and when I got home, under my house is like a lake again. I would guess there is over 3000 gallons of water in a 12 hour period.

What I have figured so far... There is no possible way for runoff to get under the house. There is also no way that that much water could have gotten under the house through seepage in that amount of time.

I think there has to be a storm drain running under my property that is backing up during rain and flooding under my house, OR there could be an underground spring that only surfaces during heavy rain. I'm not so sure about the spring since there is not any evidence of standing water or water coming from the ground on the outside of the help.

That being said, I am at a loss as to who I need to call, what to do.

I did have a foundation specialist tell me that we needed to add a sump pump under the house and all of this other draining stuff totaling over $10,000. That is not an option.

I really need to find out where this water is coming from!

Any help/suggestions would be greatly appreciated.

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House is about 60 years old. All brick.

There were gutters but were removed before we purchased.

It is a very flat neighborhood, however water does run away from the house.

There is no standing water anywhere against the house. Even if it was, I would be shocked if water could seep through the ground and brick in that short of a time period. We are talking about 3000 gallons back in the crawl space within less than 12 hours.

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Hunter, rainwater is getting into the crawlspace, it's just hard to figure out sometimes. I see that often here in coastal Louisiana.

You've hired several professionals and none have sleuthed the question for you. That's unfortunate. It has simply eluded them all.

Rainwater will not enter a crawlspace if that crawlspace has an elevation higher than the surrounding property. Not to say that it should be at a higher elevation but to give you an axiom from which to begin another attempt at sleuthing your issue.

Where elevating the house and crawlspace elevation is too expensive for my clients, I sometimes suggest adding drainage from the lowest point of the crawlspace to the municipal ditch or culvert, assuming that the available ditch or culvert lies lower than the crawlspace grounds. That, at least, will prevent long term flooding.

Which I could do more.


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Mobile topography is likely very flat. 3 inches rain in a day is enough to drown the frogs. Soils do get saturated and water can move sideways in the soil. Our area has been getting a lot of the same storm systems.

Gutters would help get roof runoff away, but there has to be enough grade on the lot to take it somewhere.

Your crawlspace has likely been wet periodically for a long time.

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My guess is rainwater as well. It is coming from the lack of gutters and most likely hydrostatic pressure. As the water percolates down through the soil and the underlying soil becomes saturated it starts searching for a way to keep moving. if you have a home with a crawlspace that is basically at or below the surrounding grade it will move towards that crawlspace. The soil in the crawlspace is relatively dry and then once it hits that area in the crawl it is basically forced up by under pressure and into the crawlspaces.

I have seen water in crawls when the only visible water is 200 yards away in a field that also doubles as a retention pond. Once that field/pond filled up a few inches the outlying homes would have water in their crawlspaces in about 2-3 days and the field/pond would be empty but the ground still saturated.

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Jim & Scott have probably identified the cause - hydrostatic pressure.

Solution #1 is to get gutters on the house to move the water WELL away from the house. The recommendations you got to add a sump pump and "draining stuff" is a good one. At 60 years old I doubt there is any perimeter drain around the house, thus the water comes up in the crawl. That the exterior grade is above the crawl is helping make it into an indoor swimming pool.

Here is the link to a thread where I talk about encapsulating my crawl space, including adding a sump pump to dry it out. https://www.inspectorsjournal.com/forum ... C_ID=18281

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Since you are selling, you are looking for a solution for the buyers, as well as for you. This can be done by obtaining a quote and then splitting the cost 50/50 with your buyers. So the $10G could be an option if you come down $5G on the asking price.

Your crawlspace probably needs a sump pit for the odd times that flooding happens.

If your property is really low, pumping might not be a solution. The pump has to have a drain far enough away from the crawlspace, out to a ditch or storm drain preferably.

You should be able to get a sump pit dug for less than the quote above, but there is more to it. The pump needs wiring and that requires a professional electrician. The sump pump poses a shock hazard because it is a wet location. The access is difficult so you pay more for that too. Wiring, excavation, plumbing and then some remedial work to the crawlspace to control dampness, that is going to add up.

Here's another approach. If repairs to downspouts don't help or there is a seasonal high water table at your property, consider raising the floor of the crawlspace with soil and capping it off with some polyethylene. Posts will need to be protected from contact with the soil.

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After adding gutters with downspouts that move the rain water at least 10 feet from the foundation, you could also considered trenching around the interior of the crawlspace. Add a drainage pipe to the exterior at the low end of the crawlspace that again gets the water at least 10 feet from the foundation. Then a plastic vapor barrier sealed to the block foundation and support columns to keep the water and moisture from creating other issues to your floor system.

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