Where is the water coming from - Help

[pdoc]

Hi Guy's

I have set about excavating under my house which had already been partially started before we purchased the house. i was having some success its rather hard clay and i reasonably dry and dusty. As i moved towards the side of the house i noticed the clay was slightly damp compared to the majority of what had been dug out. i uncovered some old pipes (see pic) all was well no water. however, a number of weeks ago when it rained i noticed the hole on the pipe side had started to fill with water. i have since confirmed that both pipes to the left of the picture are not connected (this is all under a newer extension at the back of an old Victorian house) the one to the right drops about 2m over a 4m run to the main drainage. i cracked open the pipes and confirmed no water was running through them.

but still there is water in the same area, i noticed some water under the pipe (left side of pick lower pipe) and the clay seemed to always be wet even after i dried it out the next lot of rain (after about 20 minutes of rain) the area became wet again. after looking closer and digging a little further under the pipe i noticed some tree roots around 5-6 mm in diameter, (the closest tree is about 25m away)

Finally my question - is it possible that the roots are channeling the rain from outside and its running down the roots to the point where i have unearthed them giving the rain somewhere to go!!!!!!!! or am i just going crazy!!!! the rest of the house is bone dry.<o></o>

[Spelunx]

I have no real idea about plumbing, especially in older houses, but is there any way it is storm water? By your description, if it only happens when it rains, there could be three things happening. Either the pipes themselves are being used for storm-water, there is a storm-water pipe near-by that is leaking, or the storm-water is getting under the house and it looks as though the pipes are leaking.

Sorry, I'm not much help, hopefully someone will come along soon with the right answers.

[ozwinner]

The pipes are old salt glazed sewer pipes.

Al

[Honorary Bloke]

Finally my question - is it possible that the roots are channeling the rain from outside and its running down the roots to the point where i have unearthed them giving the rain somewhere to go!!!!!!!! or am i just going crazy!!!! the rest of the house is bone dry.<O></O>

You are going crazy! No, actually, you have it a bit backwards. The tree roots are not channeling the water, but the water is attracting the tree roots. Trees will find water anywhere it runs. Look elsewhere for your problems.

Not enough info for a definitive answer as to where it is coming from, but it ain't the tree roots.

[pdoc]

thanks all i guess the only way will be to continue digging back and track where the water is coming from. does anyone know a good structural eng in the melbourne (richmond) area as i need to get some caculations done prior to further digging

[DJ’s Timber]

Is the water coming in from the high side of the property? Friend of mine has the same problem and it's from water seeping through the ground especially after rain.

The only way to fix his problem is to dig some trench outside along the wall and put some agi drainage in to take the water away before it seeps through.

[manoftalent]

sometimes water can float right across the top of clay, time, how compact it is ..etc all play a part ......I would suggest running agi pipe along the side of the house and away from that area ....removing the clay that you did altered its normal course .....so now your going to have to provide another for it to run off ....

[joe greiner]

What's the shape of the ground around the house? Ground should slope away from the house on all sides, including the uphill side. I had a similar problem; uphill side sloped down to the house, thanks to idjit builder. I excavated that side, and built a retaining wall at the property line with a gravel and filter cloth backfill, and a drain pipe at the bottom of the wall.

Joe

[pdoc]

the block is 15m wide 25m long and points north south with the front of the house facing south, we are just about on top of a hill with the block sloping from south to north and droping gradually by about 1 to 1.5m. the front except for a small garden bed is all cement so to is the drive way down one side (except for another garden bed) and the other side is next doors driveway which is also cement.

the actual water is coming out about 2m from the back of the house right in the centre, the rest of the house is dry clay and very dusty on top, the front half of the house (old victorian) is on solid bluestone footings and the rear on brick footings. there is no water pooling anywhere else and i cant find any evidence of dampness anywhere else.

I think i might keep digging and see what i find and put in a wet sump along the way unitl i resolve the problem.

i just need to get an structural guy in to check the footings and give me some caculations

What's the shape of the ground around the house? Ground should slope away from the house on all sides, including the uphill side. I had a similar problem; uphill side sloped down to the house, thanks to idjit builder. I excavated that side, and built a retaining wall at the property line with a gravel and filter cloth backfill, and a drain pipe at the bottom of the wall.

Joe