In my experience, the most common cause of water in cellars and crawl spaces is clogged gutters and/or downspouts.

First, cure the liquid (bulk) water problem you've just pinpointed.

Secondly, seal the crawl permanently. (And no you can't dehumidify the basement with the vents open!)

I think I read once that sealed crawl spaces should have a vapor barrier covering the ground. Or serious dehumidifiers set up. Or maybe both? Check with someone who knows, maybe a structural or building science/environmental engineer.

We've just gone through the permit process for new unvented/conditioned crawl space. They required insulation on the walls, drainage under the floor, and a 6 mil vapor barrier on the walls and across the floor. It also needed 2 openings into the existing basement (flow through air path), with 1 sq ft of ventilation area, and a continuous fan with 1 cfm of air circulation for each 50 sq ft of floor area. I recall a discussion about using a dehumidifier instead of the fan circulation, but I don't remember the answer about whether it is acceptable. We will not have any insulation between the crawl space and the 1st floor above, and the crawl space will be the same temp as the basement (in wintertime that is usually about 65 degrees).

All the city requirements for a unvented crawlspace included the code references, but I have not read through all of them in detail.

Bruce

"We would never have found the interior waterfall otherwise."

This is one reason I much prefer a real cellar to a crawl space. You store stuff and do things such as laundry and hobbies in a cellar, so you're there to notice when something goes wrong.

Not to mention the awkward access. Heck, if I were a tradesperson, I think I'd charge at least 20% extra for working in a crawl space.

The main sources of moisture are water, rainwater intrusion, evaporation from the soil and water vapor carried in with ventilation air.

Broken pipes are a common issue that forms moisture.

Source of moisture in the crawlspace

• Bulky water
• Moisture evaporating from the ground
• Outdoor air coming through crawl space vents

Solution:

If you have found standing water in your crawlspace then there are high chances of drainage or plumbing leak. This problem can be fixed immediately by a plumber expert.

" The main sources of moisture are water ..."

Yep.

What's the deal with this "Emme Eve"? Anybody know? The posts look exactly like a spammer's or a bot's, but they don't seem to have the usual promotional links, like the spammy Minisplit guy's posts have.

Emme Eve's profile doesn't give any useful information. Looks just like a bot's.

I'm sorry if this seems rude or unjust, but all of the "Emme Eve" posts I've seen so far have revived old threads to post generic low-content platitudes loosely related to the thread. Again, that's exactly what you'd expect from a bot. But I can't see any motivation or purpose.

Maybe I've missed something. I'm open to correction if I've misjudged them.

"This is one reason I much prefer a real cellar to a crawl space."

But, of course. However one can not have a basement in some parts of the country. Charleston, SC, is a good example. No basements, no in-ground pools except in rare cases.

Heck, in a rainstorm the Rattlesnakes and other critters used to go to high ground to escpe the rising water table. My crawl space and front stoop seemed to appeal to them!