Quicksand

[madmix]

cant see a problem here. Kids love mud.

and you could also chuck the missus in, then post
some real dirty pics for Al. (and the rest of us)

cheers Mick.

[spartan]

Fellas, how deep do you need to go with the Aggy pipe. Before we put the cubby house down on that bit of soil, the previous owners had a vegetable garden there. I assumed that there is a lot of topsoil there and that's why it gets so muddy there.

Try something like......

Excavate a square that more than covers the area where the cubby house will be....

Drop down about 140mm

At a depth of 140mm for 75mm road base, compacted.
Put down your ag pipe
for 30mm put in washed river sand.
The top soil and grass.

Let us know how you go....

[Clinton1]

tiger,
Perhaps the first step should be a 'free' solution that resolves your problem and allows you time to assess your drainage needs over the next 12 months before committing to a $200 or more 'solution' (which may not be needed anyway).

I would be checking out the area affected by the 'quicksand' for its dimensions - i.e. cubic measurements/how deep it is before you hit the subsoil. Then consider digging out the same volume of dirt out in an unobtrusive place i.e. along the back fence or in a corner, and mixing the sand and soil together.
The soil/sand under the old cubby will 'firm up' in the hole, due to the soil component (make sure you compact it well), and the sand in the soil in the 'borrow pit' will add drainage to that area. If you still have probs, consider mixing a bag of cement to the sand/soil in the cubby area to make 'stabilised earth' and then top dress this with 15 cm of topsoil.
All of this will cost you time on a shovel, give you some idea of your soil structure, and may cost up to a bag of cement. now is the time to dig, with wet soil it is easier - and you have a month or so before it warms up enough to get grass seed to sprout.

After next winter (I'm assuming you have just moved in due to the reno craze you are on - I'm in the same boat) when you have had a chance to see the effects of our winter rain on the yard, you will be in a position to judge your drainage needs. Council will let you know where the stormwater connection point is, and if you can connect into it. In my area it is 1m from the back fence, and 1 meter in from the eastern boundary - the easement runs next to the back fence. I took the poor man option and dug out the trench for my drainage by hand. I pre-planned where I wanted garden beds and used the left over spoil for the veggie patch from hell.
Soak pits are simple and easy, and a point well made, however they have their place and may not suit your situation. They can create probs if the area just fills up and won't drain (thats my block), or if your block slopes the water could run off into areas that you don't want i.e. next door.
I hate it when I don't consider things and end up spending hundreds of $ more than I should have cause I rushed in without understanding all the issues. Thats my excuse for taking the "slow and steady and bloody cheap" option where ever i can. Now you can spend the $ you saved on a BBQ for the pergola, a new toy/tool, some tree ferns or whatever.
Cheers, have fun
Clinton.
Hows the chook pen?

[Tiger]

Thanks, Clinton.

You seem to know what you're talking about and you're right I am on a reno craze for the moment. I've got some free time coming up and I have a number of small jobs that need doing, I'll post them as soon as I work out how to successfully attach photos on this forum.

The chook house is on hold at the moment. I was going to use radiata pine but the overwhelming consenses of the forum is not to use it so I'll have a look at other timber and once I decide on the cladding it will be built hopefully over a weekend. These projects have built up over the years because I was never sure how to fix them, now I've got the forum here and my chances of actually getting them done has increased significantly.

[Clinton1]

I wouldn't say that I know what I'm talking about - I just muddle along.

Probably sounded like an arrogant twit, but thats just my annoying lack of social skills, or at least thats what my last annual work report said.

Thought my viewpoint wasn't too uninformed - i shifted about 5 cubic meters of saturated clay for drainage over the weekend, so I thought my "blisters were my authority". I did a little drainage up Tully way too when younger and stoopider, 4.5 meters of rain a year tends to make drainage an issue. Always happy to stand corrected though - but prefer that to happen before I do the job. Getting the info after is proportionally annoying to the amount of pain or $ i could have saved.

Use the search function to see the "Richardwoodhead" started post. Search term is "jpeg compress". I only have a digi camera on a mobile phone - cheap bugger aren't I - so I dont put many up. However I use "jpeg compress" (freeware) to adjust the size so the photos can be attached using the 'manage attachements' button. Thats the sum total of my abilities. Its either that or use sticky tape, but my IT-head brother said that would not work for the people on the other side of the computer screen.

[custos]

One extra bit of advice - if you're going to use ag pipe (you probably want a trench about 500 mm deep to answer an earlier question) the best way to take water away is to drain it to your storm water -- by linking it one of the pipes running from your down pipe. However, if you do that, legally (I think) and sensibly, you need to put a concrete silt pit in between the ag pipe and the stormwater connection. You should also *ahem* obtain council approval before doing this. You run the ag pipe into the concrete pit (see bad drawing below), which has a grill on top to allow access in case of blockages, and then another outflow that connects to your stormwater via T intersection. Ag pipe with a silt sock costs about $6 per M, the silt pit is probably under $30, and the T intersection would be a few dollars from Bunnies. It's pretty easy to do.