Thread: soak well installation

jsandso,

Just another quick tip (now that this topic's back up the top again). If your connections between downpipe and soakwell are complete, make a notch in the topside of the lowest bend, just above ground level. This stops water backing up and doing either one of two things - blowing the downpipe out of the soakwell connection, or blowing back up to the gutter and flooding your eaves. Learnt this one the hard way after making the whole connection air-tight, and watching the whole thing fill up to the gutter level. :eek: That notch at the bottom allows the overflow to be dispersed at a lower level, while having it at the top of the pipe means that the water coming down still goes into the soakwell.

Lessons learnt at school were a lot cheaper than the ones I make around my house
Craig

Originally Posted by jsandso

looks like I have to dig the soakwell up to find out whats causing the problem.

If you do dig it up, then I recommend you put a layer of coarse bluemetal at the bottom of the hole and completely around the outside about 75-100mm in thickness. The bluemetal makes a tremendous difference to the dispersion of water OUT of the soakwell. It allows ALL of the surrounding sand (or whatever) to absorb the water instead of the water soaking only into the areas immediately next to the soakwell holes.

Using this method (advised many years ago by my bricklayer dad) I have NEVER had ANY of my soakwells overflow

I haven't read all the replies but didn't see that anyone had written that you need to be at least 1500mm from the house slab and fence line??....I had to install 6 soakwells at a new house i built in Perth and had to run a line 7metres to a soak well due to lack of space...check with council.....the best soakwells I found were old plastic 44 gallon drums very strong and deeper than the standard bunnings ones.....I got my mates around and put on a BBQ and got them all done in 2-3 hours....cost me alot in beer though.....I never had any problems with sinking or collapsing...I watered in the sand which helped compact it after they were installed...Good luck

Thanks to everyone for your help, but unfortunately even after installing a second soakwell, next to the existing one I got a phone call from my tenants today that there is again a big lake in the entry area. Apparently the water was even flowing into the garage.

The soakwells are all installed correctly with gravel around and at the bottom of them. But I can tell you that I do not want to install another one myself. It toke me almost 5 hours to dig that hole. I had to use hammer and chisel to crash the limestone rocks. I think the condition of the soil in this area is just not suitable for soakwells. Especially with so much rain we had the last couple of days.<O</O

I rang a drainage guy this afternoon and he said that I have to add as many soakwells as it takes to solve that problem, that’s all he can suggest. I asked him if one of this drainage pipes from Bunnings or so could help to redirect the water to the other side of the lawn area, but he said this is all crap and the only thing is adding soakwells.<O</O

I just don't think this going to work on this water repellent soil.<O</O

Does anyone have any ideas how to fix this problem?<O</O

jsandso<O</O

Originally Posted by jsandso

The soakwells are all installed correctly with gravel around and at the bottom of them. But I can tell you that I do not want to install another one myself. It toke me almost 5 hours to dig that hole. I had to use hammer and chisel to crash the limestone rocks. I think the condition of the soil in this area is just not suitable for soakwells. Especially with so much rain we had the last couple of days.<O</O

[color=black]I rang a drainage guy this afternoon and he said that I have to add as many soakwells as it takes to solve that problem, that’s all he can suggest. I asked him if one of this drainage pipes from Bunnings or so could help to redirect the water to the other side of the lawn area, but he said this is all crap and the only thing is adding soakwells.

There really is not much you can do, other than what you are doing already.

There could be a *lttle* to be gained by perhaps a larger soakwell, however this becomes a more difficult task in the area in which you require soakwells.

It seems, from what you describe, that the problem is not so much the soakwell or the quantity of soakwells (in a specific location) but the surrounding ground material.

Obviously, as you can already appreciate, the water is NOT going to drain quickly through limestone. Your soakwell area is described as having sufficient limestone to make it a challenge to install the soakwells.

The ground under and around the soakwell is going to make the whole process difficult.

In *nromal* circumstances the house designers have to comply with regulations and have x number of downpipes for x length of gutter. A 1mtr x 1mtr soakwell (properly installed) at each of these downpipes (in my experience) in sandy soils will cater easily for rain runoff.

If you have a particularly awkward roof design that has a high runoff into a single or limited outflow, then yes you may need more or larger soakwells.

OF COURSE you can use stormwater pipes to move the soakwell to a more suitable location (or add more soakwells). "Drainage" pipes are something else - they are perforated to allow water to soak through and are not meant for this application.

Make sure though that if you DO extend the downpipe to a "remote" soakwell, that the extension pipe has a "fall" ie ensure that the water WILL naturally flow toward the soakwell.

You cannot keep adding soakwells to an area that does not provide suffficient drainage. You will need to obtain a more suitable area or perhaps consider redirecting the current "overflow problem" to a spoon drain to let the water flow over the ground area and ultimately drain "naturally".

hi

just looking into this stormwater/soakwell thing as we are about to do an extension and came across this page while searching - the regulations appear to be some sort of state secret to be kept from the general public at all costs

have discovered so far that in perth, one downpipe is reqd to approx 37 sq m of roof, and that one cu m of soakwell is reqd for evry 80 s qm of roof. in other words .5 cu m per downpipe or 1 cu m for two downpipes.

by the way, those plastic 600mm things have a capacity of .16 cu m, which serves about 13 sqm of roof or about half the roof area to one downpipe. ie they sound a complete waste of time.

what i cant find is the distance soakwells must be from house or boundary, something which reno8ter refers to above. if it is 1500mm, which seems reasonable, that would rule out any soakwells dowmn the side of a house with a setback of 3.6m or less, which is most sides of houses. this would mean joining all the downpipes down that side of the house together via a stormwater pipe and tarnsferring the water to the back of the block, by which time one enormous (1800mm) soakwell would be reqd concentrating the water in one place instead of spreading it around.

it also means you would have to find an area 4.8m across untroubled by buildings, boundaries, pools or trees, something that is not that easy to do even on a quarter acre block.

so please, can anybody tell me what the rules are for perth for soakwell distances from stuff, or tell me where to look it up?

thanks

G,day, 2 metres (in general) is how far away they should be from a footing. Hard and fast goes out the window due to a factor know as "Council Building Regulations". These seem to vary somewhat from place to place .

The 600mm things are practically useless as you suggest. 12 to 14m2 per 600mm useless thing is what most new houses have. We generally try and talk the homeowner into putting in 1200dia x 1200h soakwells or even 1500 deep if there is no limestone sub-strata. Trafficable lids allow them to be placed under paving, driveways etc. I just finished putting a 1800 x 1800 (2 x 900 deep stacked) in a place in Fremantle. This was more than sufficient for the council on about 300m2 of roof. It was a sloping block so the owner could run all his downpipes into a 125mm drain and down to the soakwell at the front.

Just remember the bigger the soakwell the better but size and weight can be a problem for installation. We use a bobcat and 5 1/2 tonne excavator. The plastic piles of junk are dangerous if you ever want to drive into your yard or operate landscaping machinery.

Contact your council for the good oil cause I give up on what formula they are using this week:confused: .

Cheers

Hiya,

Would it be naive to suggest a rainwater tank? I guess it has to have an overflow anyway, though. Just a thought!helga

What Squizzy said.

This was what I managed to find out when I looked into it. About 2 meters from footings/slab and same from retaining walls.

Geoff

ok thanks guys

2m sounds an inconvenient distance - certainly couldnt fit them down the side of the house. think i will do as squizzy suggests - go and see the council on tuesday and ask them.

rainwater tanks - have thought about them along with most other things , but aside from the gravity problem they would need to be half empty all the time to provide the capacity to absorb more, which kinda defeats the object.

I am building a deck down the bottom of the garden and i have thought of pouring it into the void under that - 10cm void under 20 sqm of deck equals 2 cu m - equivalent to a pretty big soakwell. is that a stupid idea or ahead of my time?

Originally Posted by christmas bonus

ok thanks guys

2m sounds an inconvenient distance - certainly couldnt fit them down the side of the house. think i will do as squizzy suggests - go and see the council on tuesday and ask them.

rainwater tanks - have thought about them along with most other things , but aside from the gravity problem they would need to be half empty all the time to provide the capacity to absorb more, which kinda defeats the object.

I am building a deck down the bottom of the garden and i have thought of pouring it into the void under that - 10cm void under 20 sqm of deck equals 2 cu m - equivalent to a pretty big soakwell. is that a stupid idea or ahead of my time?

Can't comment on the under deck without seeing it, but assume you would have to have concrete or steel posts, dig out, fill with aggregate...works for me, same thing as a soakwell as long as it can't erode..just needs a bund around it.

Doesn't matter how big your rain water tank is you still have to have the drainage within your boundary. It must not be capable of running to another property or the road.

Awhile back we where building a wall at a new house and the builder put in the soakwells less than 1 metre from the footing...Council ordered them moved. This is why almost all contracts now say "drainage by owner" because it wont actually work with the design the landgrabbing penny pinching council bribing scumbag developers put on the plan. As long as they get their money they don't give a toss if the whole thing is disfunctional by not allowing room for drainage.:mad: ......better now....

Cheers

Originally Posted by vsquizz

because it wont actually work with the design the landgrabbing penny pinching council bribing scumbag developers put on the plan.

:mad: :mad: :mad:
(Not really mad, but don't tell Squizz - I want him to stew on this thread for a day or two!)

As a landgrabbing penny pinching council bribing scumbag developer, (or someone who makes his living working for them at any rate), nothing gets my goat more than people who buy small parcels of land in well planned community subdivisions, then proceed to buy the largest standard-plan house they can.

These idiots (and I use that term in a caring and sharing sort of way), rather than spend a few dollars on a larger block of land, or on some clever design which may involve things like appropriate scale and siting, just dump a plan on a block of land, cutting off bits that don't fit and then blame every one else for their lack of foresight.

So, if you buy a small block of land, please develop it appropriately, with clever planning you can do anything.

Back to you Squizzy!!
Cheers,

P (Who raised his kids on a 400m2 lot in a 4 bedroom house with family room, office, two car garage and pool, but still had appropriately scaled spaces)

to develop this deck thing further; there is a deck area (currently under construction) which i have personally dug out so that the ground (ie sand) is 100mm below the bearers, and 200mm below the joists. Because it was dug out the ground is slightly higher all round forming a natural 'wall'.

Instead of posts i am using galvanised stirrups bolted to the bearers at the top and set in a concrete pad in the ground. effectively it is a steel post.

I therefore have a 100mm clear gap under the whole of the decking forming a natural soakwell. The smallest usable area of the deck is around 20sqm, so if the 100mm was ever full that would give a capacity of 2cu m, which is adequate for that side of the house. Since the design parameters are for a once in 20 year storm, that means the bearers are going to get wet once every 20 years, which i think they can live with.

Why would i need to fill it with aggregate though? what would that do apart from halve the capacity?

If it overflows the 'soakwell' it will overflow into a garden bed to the lower side. that garden bed is going to have in it a trench filled with aggregate and pipe to distribute reused grey water. The capacity of the trench at 200mm by 200mm by 20m long is another .8 cu m or so.

I've never heard of a Soak well before, so I looked this up. Just one question, is there holes on the bottom of that mother to let the water out?


http://users.bigpond.net.au/degasperis/soakwell.html