Hydrostatic pressure and ground water
Here is a link to some beginning pictures of a job we are on.
http://www.facebook.com/pages/Seattl...82173475152440
This is a drainage problem to the 100th power! Story goes like this, get called because water is gushing out of a driveway at a home in a very nice neighborhood. I go and it looks like a water main is broke under the concrete it's coming up the expansion joints on a nice 3 car driveway. Check the meter nope not running, check the neighbors above nope nothing there either, owner has had a lot of work done, surface drains, french drains, retaining wall drains installed, all to combat water surface problems around the house. The house was actually sinking on one side and he had pin piles driven in to stabilize the house. Structaul engineer, soils engineer, I mean he has put some money toward this problem now after all this the driveway starts to gush water and it is cracking bad and it's summertime! Wait till the Seattle rains come I can not imagine it then. The biggest problem on these jobs is plumbing does not enter the picture in terms of the drains outside the home. The General contractors can do what they want almost, it was not until the 70's that footing drains became a national building code and the code is very very vague. The reason is most builders use flex corrugated pipe and tee's. No cleanouts to the system you can't make it through too many Tee's with a sewer camera till you dead end. Can't snake them very well either the snake just tears the stuff to shreds, Jet you say.., well a straight run or so yes but you might loose that jet hose and tip. Anyway they don't even use fittings sometimes just bend the pipe around to make it go where they need it. And bellies are everywhere! They think as long as the end of the line has outfall it will flow when the water reaches it's own level which is true but it leaves all the debris and mud in the lines. Now if you tie in all the homes gutter rainleaders into the system you have trouble just waiting to happen. When I go to these jobs I bring every size camera I own, I bring my longest string roll to manipulate the seesnakes head, I bring lots of different size snakes to make it through the lines if I can, and my seektech locator. I spend hours going in every drain I can and mapping it out, but it is hard to see other connections when the line is holding mud or water. I pour dye down lines I can't get through. I figure out the easiest place to dig to find the footing lines and once I know where the lines are All I care about is where it all goes to. The reason they build them like this is because nobody is ever (except me lol) going to see whats in the ground so they go cheap and spend the money on fancy front doors and tile for eye appeal.
This house had mud in many spots very bad that I had to jet just to gain the layout, many spots where crushed on install to make it even worse. Then they tied the footing drains and downspout leaders all together and reversed the grade to the outfall pipe. It filled with mud but wait they thought that might happen and instead of solid pipe they put a few feet of perf pipe near the driveway and the whole system was like a big reservoir bleeding it out under the driveway. And here is the real kicker there is a natural spring on the other side of the driveway so they ran a piece of pipe over to where it pushes to the surface (under the driveway) placed a few rocks around the open pipe and sold the home (10 years ago nothing you can do) In the coming up pictures over the next few days we excavate the needed spots (thanks seesnakes!) replace the damaged corrugated with solid wall PVC, pipe burst in a few new lines and mole some lines where there have never been any before. I love these jobs it's me vs. the water.
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Originally Posted by Gettinit
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