How to stop overflowing water from other properties?

[Barbara35]

I have an existing colourbond fence as a boundary fence between my property and the adjoining property.

I continually have flooding when heavy rain pouring through from their  place. It is like a dam has burst and we have renewed all of our storm water and drains  at a cost of $9000.

Our drainage accommodates water on our property but not the extra from behind. When this happens it floods the top level which becomes like a swimming pool and over the garden and is like a waterfall coming down over the steps  to the patio. When the water gets to the patio we have to broom it to the side so that it doesn't enter the house. We have had to have SES provide sand bags.

We have spoken to the neighbor who says his yard floods as well but says it is nature and is not prepared to do anything .

We have spoken to the Council on a number of occasions and one again they are looking into it.

We are having quotes to build a wall across the back but this is very expensive. We thought we would get cement sheeting and put that across the back to prevent this flooding. We were thinking  of making it approx 3ft high. and to go across approx 405ft 

Not sure what product to use and really need help.

[EricL]

Hi @Barbara35 

Is there a possibility that you can claim this on your home insurance? I know that sandbagging is not an ideal solution, but it is a temporary solution to prevent water from entering your home. At this point in time, I suggest trying to defend yourself against any future flooding. Any solution that requires digging or concrete breaking will take time, plus the added time of waiting for the ground to dry up. 

Eric

[Barbara35]

Hi Eric,

I must do something thoughts are sleepers imbedded in ground and up in front of colour bond fence and screwed on to it. This will block to water coming through.

Do you know anyone who could help with this?

Regards

Barbara

[EricL]

Hello @Barbara35 

Putting in sleepers will not provide an adequate seal to the water coming as the water will pass through the gaps of the fence. It could possibly reduce the amount of water coming in but now the water will flow to your neighbours which could cause flooding in their area. This now becomes a liability as you have diverted the water from its original course.

I believe that the immediate solution that you can apply is to find a way to release the water that is gathering in your back patio. I've placed indicators on your original sketch where I propose the concrete must chipped or broken to allow the water to flow out. The theory is that water will flow to the lowest point in the ground, if something is blocking the water it will gather to the lowest point of that area which is your back patio. By providing an exit for the water you will prevent water from gathering in that spot.

A good indicator that water is being trapped in a low point is that the water stops and gathers in that spot. But after that spot there is no water hence a channel or exit point must be provided to let the water out. I suggest using a Craftright 2 Piece Cold Chisel Set to chip the concrete. 

Please make sure to wear proper safety gear such as gloves, goggles and a dust mask when working on the concrete.  

If you need further assistance, please let us know.

Eric

[Barbara35]

Eric the are you have marked has already got a channel for the water to go out however the amount of water is too great and floods as the water can't get away quick enough

[EricL]

Hi @Barbara35 

If that's the case, I'm afraid the exit point for the water must be made deeper and bigger to increase the exit velocity of the water. At this point in time the drain away is not fast enough as you mentioned. Perhaps if you made the entry or exit point of the water bigger and deeper. Any change in the way the water exits the back patio will help relieve the flooding. In essence even if you get more flooding from the neighbour's fence, your main objective is to provide an emergency exit for all that flowing water. You can't have it sit and slow down in one spot, it has to keep moving.

Eric

[Barbara35]

Thank you for keeping in touch Eric.

We only have the side passages between the houses other then all  of the drains for surface water to escape. It is impossible to dig these down lower  we have air con on one side  2x 2100lt water tanks and a heat pump water system on the other. We do push the water away from the house so that is can exit through the side  passages and out onto the front lawn however the volume is so great it does not get out quick enough. As I have said  drains cannot empty quick enough because we also have the problem  we have a huge  pit in the front near the front fence so that excess water can build up there and 2 NOT ONE storm water pipes (all our storm water pipes as said earlier have been replaced with 100ml not 90ml pipe) the gutters fill up to over the kerb and does not let our storm water expel into the street. WE HAVE CONTINUALLY asked council to put another drain in the street and have notified the Council Gen Mgr as well as the Mayor of this problem. Council came out again and once again are looking into it.

I do appreciate the forum of info it is nice to know other people care.

Kind Regards

Barbara

[TedBear]

I would suggest for this circumstance that it would be good to put a soakwell under the grass next to you  patio, so the water has somewhere below ground level to accumulate during flooding times.   (Although that may be easier said than done if you have limited access to the back area.)  You may not need huge one, just enough to drop that excess water away from the door.

[Barbara35]

Hi,

Where the bottom level grass meets the patio we have drains across the middle and excess water soaks through the grass and runs under the house we then have at least 2 feet of water under the house that does eventually drain away in time. This is not ideal as can cause mold or termites  we keep checking.

[TedBear]

Hi Barbara35, 

If it's possible, installing a soakwell, (ideally two; one each side) under the lawn would give the water from those drains somewhere less damaging to be diverted to, other than accumulating under your house. Any overflow from the soakwells can be connected to your existing drain pipes to be carried away. 

If you install this system, I  suggest that the outlet pipe have a  right angle bend at the top and be extend to about 1/2 way down inside the soakwell. That way, should it get full the water will get siphoned out to the half full level (assuming that level is above the outlet level where the drains finally flow out).  This will help to regulate the flow during those damaging high demand times, instead of counting on the drain pipes to take it all away, which they just can't do in your case.  If you can set up the syphoning system then the partly emptied soakwell will have some capacity to help with a following downpour. If you can install two soakwells connect them by a pipe at their bottom outlets and they will then share their holding capacity and both will be syphoned by the one overflow outlet.

I am sorry that I can't suggest something for right now. What you are currently dealing with is awful and I hope the Council and other authorities can help sort it out at the source. 

[Barbara35]

Hi Michell this is Barbara 35 previously asking for help with water coming through from property behind.

There is someone @mort57 asking for advice.

If he would like to contact me, I could explain what we did which seems to be working at the moment.

We had flooding almost entering the house and we had to be out on the patio brooming the water away and eventually getting SES who supplied sandbags.

I know how stress full this is and would be willing to have him come and have a look

Regards

Barbara