[Skoorb]

I was just over at our new construction tonight (a couple months left to the build) and unfortunately noticed what looks to me like a substantial build up of an "orange algae". I cannot tell if this is the "iron bacteria" I've seen online.

This house is on a hill, but we get a good thousand gallons of water/day into the foundation. It's a block construction on footings that were formed with gray rectangular forms that have slits in them, with liberal amounts of gravel on both sides of that. When excavated I saw substantial amounts of sand top few feet, and then a thick, impervious clay.

13 days ago a gravity drain was installed. We also have a sump pit and it will serve as a backup should the gravity ever backup and its check valve kick in.

It looks like algae. It can't possibly be dirt because it holds together in those strands and hangs on to the inside of the gravity drain. The sump pit has a mild swamp smell to it. At the gravity outlet the "what is this" has new brown chunks of what just simply look like algae to me. They seem to wrap around twigs or rocks.

My concern: If this continues at this rate it will eventually clog the footings/gravity drain/sump pit. Is this a reasonable concern?

 

[Nealtw]

Take a sample to a lab and have it tested so you know exactly what you are dealing with.

 

[lenaitch]

It certainly looks organic - perhaps iron oxidizing bacteria but as Neal suggests, have the water tested rather than guess from photos. Since the ground water has been disturbed by construction it may flush clear over time - or not.

 

[Skoorb]

Take a sample to a lab and have it tested so you know exactly what you are dealing with.

Great idea. Going to try and find a place to do that. Not sure exactly what sort of business would do that--I'll try a home inspector company, see if they know.

I don't think it's algae because algae needs light and this is "growing" without it, leading me to think it's the iron bacteria / iron ochre.

On the other hand it doesn't look quite red/rusty enough maybe.

Perhaps lenaitch has a good point and it's related to soil disturbance only.

 

[Nealtw]

Great idea. Going to try and find a place to do that. Not sure exactly what sort of business would do that--I'll try a home inspector company, see if they know.

I don't think it's algae because algae needs light and this is "growing" without it, leading me to think it's the iron bacteria / iron ochre.

On the other hand it doesn't look quite red/rusty enough maybe.

Perhaps lenaitch has a good point and it's related to soil disturbance only.

Just google industrial lab and your city.

 

[Skoorb]

Just google industrial lab and your city.

Brought into a lab today. There is an iron bacteria test but it requires it to be sent out. However, the company was familiar with it and feels this is iron bacteria based on pics and inspection of a sample.

Of course the big unknown now is whether it's enough to worry about or not. Seems to be a substantial build up in two weeks but I have no experience in this.

 

[Nealtw]

Brought into a lab today. There is an iron bacteria test but it requires it to be sent out. However, the company was familiar with it and feels this is iron bacteria based on pics and inspection of a sample.

Of course the big unknown now is whether it's enough to worry about or not. Seems to be a substantial build up in two weeks but I have no experience in this.

I have never seen it either. Is it in the drain pipes that dump into the sump or is it just starting in the sump?

 

[Skoorb]

I have never seen it either. Is it in the drain pipes that dump into the sump or is it just starting in the sump?

Ah, it's everywhere really. In the sump pit you can see some rust colored crusting on the sump pit walls, which who knows what that is. But on the white PVC you can see the yellow pretty clearly along with the algae/cotton looking fluffy stuff on the sump pump itself.

But now that the gravity drain is running this stuff is mainly there because that's where most of the water is.

There are ways to chemically deal with this stuff, but they require regular maintenance and there's still no way to get chemicals effectively at the footings--certainly not on both sides, and certainly not when the basement is finished.

At this point, given the amount of water I have, I think the builder was remiss in not recommending an engineer vet the site (soil test, sample holes, etc.). This all should have been discovered before we broke ground.

It does smell fairly gross when right up near it, like an aquarium.

 

[Nealtw]

Ah, it's everywhere really. In the sump pit you can see some rust colored crusting on the sump pit walls, which who knows what that is. But on the white PVC you can see the yellow pretty clearly along with the algae/cotton looking fluffy stuff on the sump pump itself.

But now that the gravity drain is running this stuff is mainly there because that's where most of the water is.

There are ways to chemically deal with this stuff, but they require regular maintenance and there's still no way to get chemicals effectively at the footings--certainly not on both sides, and certainly not when the basement is finished.

At this point, given the amount of water I have, I think the builder was remiss in not recommending an engineer vet the site (soil test, sample holes, etc.). This all should have been discovered before we broke ground.

It does smell fairly gross when right up near it, like an aquarium.

I am not sure anyone tests for this kind of stuff but i would check with hear by neighbours to see how wide spread the problem is and if it should have been known, even by the city who could have called for some treatment as part of the build.

Do you have drains in window wells or stair cases on the hill side of the house?

 

[Skoorb]

I am not sure anyone tests for this kind of stuff but i would check with hear by neighbours to see how wide spread the problem is and if it should have been known, even by the city who could have called for some treatment as part of the build.

Do you have drains in window wells or stair cases on the hill side of the house?

Nope, the high windows on the basement we only have a couple of 2 course-high windows, and graded away from them.

I asked one neighbor--slightly down the hill from me--and she said her sump doesn't run much. Go figure. I dunno what's up with my lot *shrug*.

The house they are building up the hill 80' from mine has no such problem because they lifted it way higher up, with much less excavation.

 

[Nealtw]

Nope, the high windows on the basement we only have a couple of 2 course-high windows, and graded away from them.

I asked one neighbor--slightly down the hill from me--and she said her sump doesn't run much. Go figure. I dunno what's up with my lot *shrug*.

The house they are building up the hill 80' from mine has no such problem because they lifted it way higher up, with much less excavation.

We did a few houses near a spring that had lots of water flow, the engineer called for it to be dug deeper and add 5" stone so the water could continue to flow under the basement.



Your builder could dig down and add a clean out to the system where you might add treatment.

 

[Calson]

I would bite the bullet and put in a French drain to take the water away from your house and the foundation if at all possible. Not cheap to do but the best long term solution overall.

 

[Skoorb]

I would bite the bullet and put in a French drain to take the water away from your house and the foundation if at all possible. Not cheap to do but the best long term solution overall.

Yeah I'm thinking we'll have to do it. No idea what a 6-8' deep curtain drain around half a house is going to cost. I guess I'm about to find out. I think we can have it 15' away from the house or so and it will grab the bulk of the water.