Browse Forums Building A New House 1 Jan 24, 2010 9:42 am hi my house is allmost finished,and ive been worrying about the stormwater, my stormwater runs from the front of my house to the rear. i have to install a stormwater pit near the front of my house as there is a low spot there. so i have the 90mm pipe sticking up out of the ground for me to do at a later date. i have noticed water sitting in the pipe,this is a worry as this is supposed to be the the high spot, water should be running away from this. so i poured some water down pipe to see if it would run to the rear of block were the l.p.o.d was. i poured roughly 40 litres down the pipe and after 5 mins no water had came out the end, what is going on i have my final walkthrough with the builder monday , and ill point this out to him. is it to much to expect him to redo the stormwater run, as im convinced there isnt any fall in the pipes. what would you do ? Re: stormwater pipes, not enough fall from front to back....... 2Jan 24, 2010 10:06 am When your stormwater pipe goes to the rear of your block, where does it then go (absorption trench, spreader trench, continues through your neighbours, etc)? Demolition August 2009, Construction Started September 2009, Completed December 2010 Re: stormwater pipes, not enough fall from front to back....... 4Jan 24, 2010 11:05 am OK, now I get the picture. So you put water in one end and nothing came out the other end. Logic would say that there is an obstruction or leak. For reference purposes a 90 mm pipe would hold about 6 litres per metre of run. So if you're pipe runs for 30 metres, you would need 190 litres of water to fill it up if there was a full obstruction 30 metres downstream. Actually, this brings up an interesting experiment. If water is going in and not coming out, there's either an obstruction or it's leaking out. We can tell which quite simply. Pour a measured amount of water (but not much more than 6 litres per metre of run) until you can see water at the inlet. See if any comes out the outlet. Once the water is seen at the inlet, see if it slowly drains away. Better still, pour water in at a measured rate and you can measure leak. If nothing comes out the other end, this leak is from the pipe into the ground. If you see some water coming out of the outlet then if it matches the inlet rate then at least there's no break causing a leak in the pipe. Basically, you want to establish if there is a break in the pipe causing water to leak into the ground or an obstruction (partial of full), which will prevent the water coming out. If it's a full obstruction the number of litres divided by 6 will tell you how far into the pipe the (full) obstruction is. We eagerly await the results from your experiment. Demolition August 2009, Construction Started September 2009, Completed December 2010 Re: stormwater pipes, not enough fall from front to back....... 5Jan 24, 2010 1:18 pm this happened to us. We rang and rang and rang until they came and fixed it. There was not enough fall on it. Then we found another problem with the stormwater and couldn't be bothered dealing with the stupid plumbers anymore so we rang the plumbing commision! Thank you Splashers. Tomorrow I might check if I can get a few packs of 300x300 in the same tile finish. It may be good to use these could in the shower recesses. I'm not… 4 5257 I've got a challenge here. Background is the builder has cut too deep for the slab and the slab is now below the very substantial retaining wall. It's failed occupancy… 0 18812 AS4654.2-2012 External Membranes it is "Informative" but if you get water ingress your insurance assessor will go to this straight away and if not achieved, they will deny… 9 2769 |