How to stop ground water coming out from unconnected pipe?

[approachmhn]

I have an old pipe that is not connected anywhere which is next to storm water pipe that runs towards road. 
The issue is when it rains, water comes out of this unconnected pipe and ground gets very damp in that area.

recently I dug that area and got plumber. Plumber put a cap to the pipe and asked me to monitor if water still gets out of  pipe when it rains.

i see it still slowly fills up the area meaning water is also coming around that pipe.

This unconnected pipe is under driveway which is concrete and solid. No gravel around pipe. So, I suspect the damage to pipe is very near to the opening.

my questions is

1) how do I check the damage

 

 to pipe?

2) if pipe is not leaking or if I can fix that leakage, how do I connect unconnected pipe to storm water pipe so water would not flow back. Unconnected pipe is around 1-2 inch below storm water pipe. 

Appreciate your help.

Regards.

[Dave-1 · Accepted solution]

Morning @approachmhn 

One more thing to add about any standing water in a pit is you will get mossquitos. 

Having a system that dosnt require maintenece and will work in a downpour while you are inside nice and dry except for running out to see if you work is working as it should be is a lot less worrying.

Dave

[approachmhn]

Thank you. 
That is my main concern. I just don’t want to deal with maintenance or constant checking.

Running pipe under deck is my preferred choice. 
Will see how it goes. 

Also, for installing pump and pit, I am getting no less than $3k quote. I have done 90% of the digging part. Also there is electrical socket near by.

[Dave-1]

Morning @approachmhn 

Just to put your mind more at ease, The stormwater replacement job I have done  at my place would have pegged out around 10-13K plus (Have a plumber mate who told me that after I was doing my stormwater pipe rectification) Like you I didnt want to spend the money and I dont mind digging. The fall of a stormwater pipe is only small, as long as the pipe is sloping downwards its good. I went over the top in replacing mine (As in much deeper then aplumber would generally do)

My "time" is free for me, the material costs and any specilised plumbing that needs to be done can be accomodated. Getting rid of concrete or other material you dig up is also something to keep in mind cost wise.

Dave

[approachmhn]

Right @Dave-1 . Thank you.

I have gone through your post and your work was simply amazing. Lots of detailing.

I don’t see any concrete under the deck. I can take care of dig up.

May be I need to dig a metre or two to get that fall. 
Will start this week and see how it goes.

Will update as I progress.

[approachmhn]

The trench will slope down under the deck and some part under house.

After renewing with  pvc pipe, my plan is to backfill the trench.

My question is,  will rain water  seep through the trench and flow through after backfilling as land is sloping down?

In that case, what are my options to avoid water seeping towards trench from outside?

thanks

[JacobZ]

Hi @approachmhn,

Assuming you back fill and compact the soil that you originally removed from the trench, you likely wouldn't get any more ground water than you did previously. There may be some minor changes as you won't be able to completely replicate the original conditions of the ground, but it would be a marginal change.

If you are concerned about ground water flowing through the trench, you could always add some drainage gravel, geotextile membrane and agi pipe alongside the pvc pipe and then have them connect into the same stormwater outlet. Instead of preventing the groundwater from flowing to the trench, this would manage and divert it to where you want it.

Let me know if you've got any other questions. 

Jacob

[Dave-1]

Afternoon @approachmhn 

What are you backfilling with around your pipe? If its gravel then yes it can have water seep down it tho I have not found it to be a problem at all.

If its clay then it will seal the area around the pipe so that kind of stops that worry. @JacobZ idea is a good one as it combines both of what you are trying to do. 

Note - The reason I used gravel around my stormwater pipe is that the plumber recomendaded it strongly and also for longetivity. I saw what a couple of decades of comprssion of clay on thin walled PVC does (squishes it flatter then flat bread) so figured Im going to the effort, I might as well do the best I can.

Dave

[approachmhn]

Thank you @Dave-1  and @JacobZ 

Plumber actually backfilled with gravel. Not because he wanted to but that was the easiest to do because clay had hardened and was not easy to backfill.

There was about 20 cm of gravel mixed sand on top and then clay under.
While digging I had separated them.

When plumber was fixing last Wednesday, I was away for 10 mins towards the end. By that time he backfilled gravel and put some soil on top. Asked me to backfill clay later once backfill settles.

Also, he just closed the deck boards without backfilling under.

A light rain yesterday and I could see water flowing because one of the deck boards was not screwed.

          Called him to ask. He said he will make a pit to soak water and was not ready to accept the issue.

Most of these people will have 5 star reviews. Not sure how they get it.

I had to dig again this morning and backfilled with clay first. And compacted the soil as @JacobZ suggested.

Hope this will fix.

It’s too late for me to do agipipe. Sorry

I was waiting for rain to check and update you guys in this forum, but had to go through this.

will wait for another rain, and see how it goes.

[Dave-1]

Evening @approachmhn 

Its done, you know the steps and now its wait and see. If not then re-access but crossing fingers it will be fine.

You dont need the agpipe so I wouldnt stress too much, the gravel, trench will also work to carry water away

Dave

[approachmhn]

Yes. It’s done. Thank you for all the support.

My only worry, trench goes under deck and then under house. 
Deck is ok. Any water under house is not good.

Hope it will be fine 🤞