Browse Forums Landscape & Garden Design Re: Backyard Flooding and Drainage Problems 3Aug 31, 2014 10:40 pm 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Backyard Flooding and Drainage Problems 7Sep 07, 2014 1:52 am 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Backyard Flooding and Drainage Problems 10Sep 10, 2014 12:26 am 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Backyard Flooding and Drainage Problems 13Sep 10, 2014 12:27 pm tacet I could be wrong about the size and number of stormwater piping. I will try and do some investigations into that to properly work out what the current system is. Should I do some digging in the yard and try and measure the pipes? I know there is more than one pipe in the backyard joining all this up, but the end output, at the gutter on the street, is simply 1 x rectangular outlet, similar size to the metal rectangular downpipes you see. I'll measure it but is that effectively the smallest hole we are working with? If the only stormwater drainage you have is what goes to the street, then you only have the one pipe. The saving grace is that there is a decent slope. I would measure the pipe for interest sake. The 90 mm PVC stormwater pipe has a 90 mm outside diameter, the 100 mm PVC pipe has a 110 mm outside diameter. Are you sure that there isn't another stormwater connection? There will be a lot of water coming off your roof during a 1:20 IFD. tacet If this whole system is in fact underdesigned, once I start adding extra drainage points and trying to get all the water to follow it, will it just back up and then the water will just sit in the yard until there is space in the pipe for it to go? Or will it also block up in the downpipes? What type of downpipes do you have? If they are metal, then there will be a plastic downpipe adapter at the bottom. The adapter should not be sealed, any back up needs an escape route but sometimes they are sealed. Excess water flooding out of the plastic adapter is bad news in any case. You have a 1 metre height difference between the front and back but you lose some of this with the pipe depth but you still retain a very good slope. The possible problem I see is that if you address the soil height at the back of the house and match the lawn height to suit, how would an ag pipe's pit outlet depth then relate to the stormwater pipe's depth? An unknown factor is the stormwater pipe's current depth in relation to the damp course. It is not unusual for builders to have the soil level too high and this can result in the plumbers coming along and errantly working off that level when laying pipes. You need to determine the stormwater pipe's level as a first step. It is probable that the soil level was raised after handover when the lawn and edging was put in, meaning that the pipes are at the correct depth but you need to check. tacet Co-incidentally, at the street right in front of my house is one of those big stormwater inlet holes in the gutter ( you know the ones about 1m long), which is about 10cm away from my stormwater 'outlet' that goes to the gutter. I wonder if this is more looking like I need to rip up the concrete path on the LHS of the house, run new 100mm piping and some how connect/incorporate this to flow into this drain (if that is even legal/able to be done). I think that once you establish the pipe's depth and size and plan the order of work, you should talk to a drainer. He will know about levels and permits etc. There will still be a lot that you can do yourself. I wouldn't skimp on addressing the ponding, the soil and the future finished concrete levels at the back of the house though. tacet Another question I have, Is there any benefits to concrete path, as opposed to paving? Paving is permeable, concrete is impermeable. A suitably coloured concrete `path' would look a lot better than plain concrete. The stormwater outlet in the photo looks to be 75 x 75 mm or thereabouts. I have no idea why they used metal and not PVC in the concrete. 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Until you find the cause of the flooding you need to take action to mitigate potential damage to your home. Get automatic float pump and dig a pit then connect to power… 2 4845 The bottom of the downpipe has been taped (see the black tape) to seal the necessary gap between the downpipe and the adaptor that would normally prevent the downpipe… 3 9193 Need more photos from around the house including your gutters. We have had 3 of the wettest years in a row for some time so that wouldn't be helping 3 6939 |