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Groundwater vs treated water

Groundwater vs treated water

Groundwater vs treated water

(OP)
I have water seeping from under my slab.  3 holes dug around the perimeter in this area show seepage on the slab side of the hole although it only pools in the middle hole.  A pressure test on the water line indicates no leaks.  Also shutoff inside valves for 6 hours last night and no movement on the meter.  Filled the sewer lines with water and it held.  I'm down to two options (I think): my neighbor has a leak on the opposite side of my house and it is migrating under my house, or I have a spring underneath the foundation.

I tested the water in the hole with a pool test kit and it showed zero chlorine and only a hint of bromine (cheap Home Depot test kit).  Samples of my tap water indicate high chlorine and high bromine.  Samples of a pond nearby indicate zero chlorine and high bromine.

Here's the question ... if treated water is coming from my neighbors house, would the soil filter out the chlorine and bromine?  The soil is a very thick black clay with a 1.5" thick band of crumbled limestone at about 1 foot down.  And of course a layer of sand is under both houses.  The water appears to be coming through seams in the clay a few inches above the limestone.

I hope somebody can help with identifying the source of my water and then recommending a course of action.  The house is 3 years old.

<tg>

ps. I'm getting this message, "Search functionality is currently undergoing routine maintenance and will be back online shortly.", so please forgive me if I'm asking a frequently asked question.

RE: Groundwater vs treated water

I would guess that the thick clay cannot pass any significant amount of water nor could it filter out the chlorine and bromine.  The limestone layer could be transmitting water from ground / surface water sources.  Locate the source and flow direction and then you can plan a method to intercept the water.  However, be careful - if you divert this water and the clay begins to dry out - your subgrade could settle.  Is your house foundation able to resist the settlement without cracking?

RE: Groundwater vs treated water

It is difficult to tell if water from the ground is from treated water or if it is natural groundwater.  One of the reasons is that often it is a mixture of both.  Depending on your location, you may be able to have a sample tested for Floride/Florine.  Chloride/chlorine tends to get filtered out of the water very quickly and therefore is not a good indicator.  Never trided using bromine.

There are several ways of handling a groundwater problem, however, as cvg pointed out you can create new problems.  I recommend that you contract a local geotechnical engineer and see if they will look at the problem for you.  If no engineering, field, or lab work is needed; most will give you some advice for nothing.  

RE: Groundwater vs treated water

(OP)
Thanks for the feedback.

The bromine test was part of the kit I bought.  I think it's a spa/hot tub test kit.  I read online that bromine in the soil is a result of agriculture (eg. fertilizers, pesticides, or something).  I can see how the runoff water into the pond would have a higher bromine content than water that is coming from underneath the surface.

"thick clay cannot pass any significant amount of water" is definitely the case.  I dug an 18" deep hole in the middle of my yard yesterday and ran water in it.  I don't think the water level changed at all in the last 15 hours or so.

This leads me to believe it could possibly just be a drainage problem.  Maybe the sand layer under my foundation is holding water because it doesn't soak into the clay.  The water just found a place to seep out.  The original hole is not holding as much water now.  I've scooped it out a few times and it's not refilling as high.  If I get all the water out from under the house, it may just stop seeping until we get the next rain...

I've contacted warranty services and they are going to come look at it.  We're scheduled to break ground on a swimming pool in the next few weeks so the last thing I need is for the warranty folks to blame future drainage/foundation problems on the swimming pool.

<tg>

RE: Groundwater vs treated water

(OP)
Secondary issue...
A french drain was installed along that side of the house when we first moved in because it had rained heavily a few days earlier and exposed a drainage problem in our backyard (drains to the front curb) that the inspector flagged.  The drain is probably 12" to 14" below the foundation/soil line, but higher than the bottom of the beam.  

Apparently there's a high spot in the drain because it is currently holding some water.  I shoved the garden hose down it and flushed it to make sure there was no blockage.  So now I'm contemplating how to solve it.  I can dig up the drain and try to get it all flowing down hill, but that would appear to be a lot of work.  

So I had this thought and I'd like some feedback.  If I run a small hose through the drain well past the hump, and then attach one end to the bottom of the drain where water is standing, would a natural siphon effect occur when rain fills the drain/hose?  I'm thinking the drain would lower the water level to the hump, but the hose would continue to flow until the remainder of the water is removed.

Any thoughts?
<tg>

RE: Groundwater vs treated water

Thats a tough one . However , if you have sprinklers , you may have a broken irrigation line runnung under you slab .
I have seen where a home is under construction and before
the driveway was poured , irrigation contractors laid a line across and buiried them and the slab was poured right on top . Also , If you live here in Florida , artesian wells and springs are quite common . I would try to turn off the irrigation line to your home for a couple of days
to see if thats the trick . If you have reclaimed water to run your irrigation , you need to find out where to turn it off . I know most high end communitties use reclaimed water to supply homes with irrigation . Also , reclaimed water only goes through a primary plant (which means it is not treated with chlorine and other elaborate methods of disinfectioning chemicals) which may explain the absence of chlorine . However , the bromine is a good indicator of a brine well or a nearby ocean . As far as warranties , you may want to hire a consultant to X-ray you lot to obtain somewhat a profile
of the sub soil characteristics . Good luck .

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