Drainage issue side of house

Hi Guys,
I am new and wanted peoples advice.
I am in a 7 year old house on a concrete slab. I am experiencing pooled water that is running from my neighbours property to mine.
There is approximately 1.5m of distance between the house and the fence line.
I have read several posts and watched videos to determine what are my options. As far as I can see one option is to sloe the ground away from the property and place an ag line in close to the fence and run this to the storm drains at the front of the property.
So the questions I have are:

1. Is this a viable option? Are there any other options I should be looking at?
2. Who would be best suited for this work, a plumber, Builder or landscaper, or a combination(The plumber for the ag line and landscaper to slope the ground?
3. Who or what is peoples advice on validating the persons proposal ?

Any advice would be much appreciated.



I have uploaded photos of the pool of water present in todays rain.

Option 1 before all else - speak to your neighbours.

Unless it is water following the natural course of ground, it is their responsibility to not have water flooding into the side of your house!

If that fails, then consider your options. A slope away from your property, and possibly the AG drain may be a good option - but might be worth getting an opinion from landscaper to do something that also includes better drainage.

As far as I am aware the the water flooding from their property is related to the gradient of the land as the neighbours property is slightly higher than ours.
Not all the water I suspect is from their garden, as I did not see any water flowing from them to us where the gate is at the end, but there is water still pooled there.
If the lanscaper were to slope the ground away from the house what are the standards for NSW in terms of gradient for every meter?
Also I was thinking I would need an AG line would be better as I would like to get the water out of that area as quick as possible but there are other options?

Does anyone know of a reputable landscaper that would quote on this type of work in the Camden NSW area?

Thanks

I 'recently' had to put in some AG drains and ensure a slope on my property. The reasons for it are different to yours. But nevertheless, I thought maybe my recent experience may help to a degree.

In my case, I had a landscaper and a plumber for the job. The key job for me was concreting the perimeter of my house. One area is similar to the picture you've shared. Without the concrete, water would seep and pool in that area. This affected the house as it's on highly reactive soil.

Long story short, the plumber was responsible for the AG and ensuring that it was directly properly to the storm water. He worked with the concreter to ensure the appropriate fall into the AG drains (I had 2 installed).

Good luck.

You have several issues.

There is water pooling next to the house and so I am assuming that you have only recently purchased in light of the house being 7 years old. I also have to assume that the house is not on reactive soil if there is no internal cracking, hard to close windows and doors etc. Am I correct?

The water will be seeping to its lowest point and you also have slope towards the house. What type of surface does the neighbour have abutting the fence line?

A real worry is that it appears that the DPC is barely above water level. Is this correct? You need to check this urgently. If so, the landscaping all down the side needs rectification and this will require a fair bit of labour.

Slope requirement is for a 1:20 slope (50mm over the first metre).

Surface drainage must transfer from a silt pit to the stormwater and a plumber licensed to do drainage must do this.

Does the ground pool water only during heavy rain or at most times?

Hi SaveH2O,
Q: I also have to assume that the house is not on reactive soil if there is no internal cracking
I am not sure what type of soil it is on. How would I find this out? We have not see any issues with cracking or windows not closing.
Q: What type of surface has the neighbour got abutting the fence line
They just have their garden grass and some stones along the fence line.
Q: DPC is barely above water level. Is this correct?
As far as i can tell it is not very high above the level of the ground. Is there any standards as to how high it must be?

If so, the landscaping all down the side needs rectification and this will require a fair bit of labour
Who or where would I go to get this started?

Thanks

I don't think that your area is known for highly reactive soils, if the water has been pooling against the house for 7 years and you are on H1 or H2, there would have been indications by now.

There is a lot of information available online, soil maps etc. The council is also a good source but I don't think that there are any soil issues here.

https://www.camden.nsw.gov.au/assets/pd ... mework.pdf


Yes, the water source is unintended seepage and an ag pipe would be the go.

"The height of a DPC, or flashing serving as a DPC must be not less than—
(i) 150 mm above the adjacent ground level; or
(ii) 75 mm above the finished surface level of adjacent paved, concreted or
landscaped areas that slope away from the wall".

The separation isn't only to prevent water ingress and allow egress, it is also an issue with termites and other pests.

The 3 Part National Construction Code (NCC) can be downloaded free of charge. The 2019 updated edition will come into effect on 1 May 2019.


You need to decide as to what you want for the finished surface and go from there but whether you get a landscaper or concreter, they will have to work in with a plumber. Because you will require a silt pit, the plumber will have to know the depth of the stormwater connection.

If you have a good plumber, he will know other good tradies he can recommend but finding a good plumber with integrity can be a challenge.

Thanks for the advice SaveH2O,
In regards to the DPC. Should i request the landscaper to lower the ground level by a minimum of 150mm? That's quite a drop compared to the land around it. Would this cause more issues with water running into my property from the neighbours?
I have asked the council for the geo-technical report for my property so I should be able to see exactly what soil type we have.
Regarding the silt pit. Are they normally placed just before the entrance to the storm drain at the front of the property?

Thanks

Great advice from SaveH2O but I would take a drill and put holes in your drains below downpipes shoe as low to the ground as possible for emergency drainage pending slope and drainage repairs. You will need two types of drains: spoon drains for surface water and ag drains for sub soil drainage. Lucky for you your drains are close by so its not rocket science.
If after seven years of water pooling you don't have house damage you probably don't need to do too much other than surface drainage improvement.

Thanks building-expert,
Just so I understand you correctly.
You would recommend:
1. Slope the ground away from the house
2. place an ag line in along the fence line
3. Would the spoon drain sit closer to the house than the ag line?
Would both drains run to a silt pit or would the spoon drain do to the downpipe connection and ag line to a silt pit?

Is it worth getting a building inspector out to offer the best way forward to resolve the drainage issues?

Thanks

Hi Guys,
First of all apologies for the terrible diagram
I am not looking to concrete it. So based on your replies and a couple of discussions I have had, does this diagram look like the correct solution?

If this is correct:
1. how deep must the ag line be? Should it be at the same height as the slab?
2. where would the stormwater drain flow into?

Ag line must be at least 1 m away from slab edge and should be deeper than bottom of slab

The plumber will know the location of the pits.

EDIT: AS/NZS 3500.3 is a “deemed to satisfy” document listed in Part D2 of the Plumbing Code Australia (PCA) and contains sections on "Surface drainage systems – design” and “Surface and subsoil drainage systems - installation”.

The PCA is Part 3 of the National Construction Code (NCC), the NCC can be downloaded free of charge.

So looks like i guessed the width from the house to the fence line incorrectly. instead of it being 1.5m it is actually 1m, which means it would be incredibly hard to put an ag line in at least 1m away from the wall.
Correct me if I am wrong but would the only option left be a retaining wall on the boundary and place an ag line on the high side?
Obviously I would have to get my neighbours approval as well as councils.
Would this realistically be the only option left?

I would like to have someone come out and have a look:
Who would be the best person to consult, that would know the standards and potential issues based on soil type etc?

I feel a few landscapers I speak to just say throw in an ag line and you will be fine, some have said you can place it close to the house others keep it against the fence line, but when I speak to you guys you are giving me standards around slope and ag line distance from foundations, which I would like to meet but are hard due to the distance.

I appreciate the responses so far just trying to get a clear way forward to resolve this.

Google "angle of repose" but you need to do something so basically just have the ag pipe as close to the fence as possible and definitely NOT next to the slab.

You could finish the surface area with landscaping pavers and suitable ground covers and other grass like plants in between to help keep the soil from becoming too wet. In life, we should always try to turn a disadvantage into an advantage.

Interesting read, thanks guys. I have exactly the same issue, but the water is pooling on the fence line. See photo attached.

I will contact a plumber to address this, and hopefully an Ag Pipe + silt pit fixes this.

Can we use that pipe sticking out from the soil to connect the Ag pipe to? It's in the middle of the photo in between the brick wall and fence. I remember that the builder mentioned that they are inspection pipes and that we could put a drain on them or even seal them and leave them under ground.

Given that I built on a P - E site, installing artificial turf + plastic underneath (which one?) around the perimeter is fine? Most people put concrete on the sides, but we are thinking on laying artificial turf.

Additionally, would a "French drain" (PVC with holes at the bottom) work better than an ag pipe in this case?

Thanks!

Use inspection opening to get rid of the water FAST,
Far end of you puddle is almost at the slab edge

This is perhaps the definitive guide to stormwater management for our Australian homes. Compulsive reading, actually, once you get started!

https://www.catchmentsandcreeks.com.au/ ... -print.pdf

Yeah it is but my head hurt for hours afterwards

Lol! Know exactly what you mean!!!!!!