Browse Forums Eco Living 1 Feb 16, 2014 1:02 pm I've done a lot of reading of these posts and others regarding setup of rain water tanks. I live in a rural area with no town water supply so we rely solely upon catchment. We are about to start major extensions and renovations to our house and a lot of info I've read from homeone has been invaluable. Thanks. I am wondering how I find out what the local area 1:20 ARI is for calculating gutters, down pipe and tank capacities. We live about 10km north east of Singleton NSW. Thanks in advance. Re: 1:20 ARI info for water tank 2Feb 16, 2014 2:21 pm Hi This link explains how to find out both the rainfall intensity for any location in Australia: http://www.anewhouse.com.au/2014/02/rainfall-intensity/ The Harder You Try - the Luckier You Get ! Web site http://www.anewhouse.com.au Informative, Amusing, and Opinionated Blog - Over 600 posts on all aspects of building a new house. Re: 1:20 ARI info for water tank 3Feb 16, 2014 6:40 pm The Singleton 1:20 ARI is 150 mm/hr. This represents a 5 minute average rainfall intensity of 2.5 mm/min. The 1:20 ARI is used to calculate the maximum roof areas that can drain to varying sizes of gutters and downpipes in different regions for roof drainage compliance. The link provided by bashworth is excellent; certainly beats looking at the contour maps in the Standards. The coordinates needed for Singleton are below. SINGLETON Latitude south: 32.61 Longitude east: 151.17 People are advised to calculate their water tank inflows (particularly with wet systems) based on their region's 1:20 ARI plus a margin so they can work out their required wet system head and tank overflow capacities. This is not regulated and related advice found on Govt and other websites is generally poor. You might be interested in reading the Which Gutter? thread in this sub forum. The Lysaght link is down at the moment but the information has been pasted later in the thread. viewtopic.php?f=35&t=60789 The following may also interest you. Note that I do not endorse the final design example (downpipe positions). http://www.pic.vic.gov.au/__data/assets ... water3.pdf Your wet system water quality will improve out of sight if you use leaf diverters, the sediment traps and the additional low restriction inlets that you have probably read about on this forum. 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: 1:20 ARI info for water tank 4Feb 17, 2014 10:26 am Thanks for the link Bashworth. I found it very easy to use and informative. Thanks very much SaveH2O for your well written advice. I have learnt so much from you by reading many of your replies. I knew nothing at all about this topic a few months ago. I have learnt that everything in the existing house is wrong as well as modifications I have done previously. I definitely understand why now. I will be talking to the builder about gutters also. I have just built my shed with trimline slotted gutters so I think they will be ok. I have to look into all the calculations a bit more yet. Just trying to get the wet system right. Definitely getting leaf guards and a flush system. Thank you again. Re: 1:20 ARI info for water tank 5Feb 17, 2014 12:05 pm Thank you. Glad to help. bashworth's blog is packed with valuable information, links and good humour. Some of the fail photos are classic! Well worth a read if you haven't done so already. Standard wet systems have problems but are simple to do correctly. In the 2010 census, over 830,000 households were found to be reliant on harvest rainwater and one could reasonably assume that most would have wet systems. By plumbing in some simple inexpensive 'tricks', water quality can be improved and the need to regularly 'flush' the pipes is substantially reduced, increasing yield. One property owner who contacted me through this forum flushed over 2,000 litres to waste whenever he drained his wet system pipes. After doing some minor modifications, that is now a thing of the past. A lot of plumbers fit first flush diverters to the top of vertical risers. While it is compliant to do so, it has no benefit because the first flush diverter only fills with the water left in the riser...the first flush is still in the downpipe at the other end of the wet system!!! Don't fall for this trap. Numerous pumps are also incorrectly installed, often against the manufacturers instructions and conditions of warranty. 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. 18 90422 From what I know about water tanks (I've been working with a client on them for a few years now) is this - The concrete can last a lifetime if they don't crack for some… 2 10620 If you can calculate the reasonable charged head from let's say 100mm below the gutter to the top of where the vertical riser's horizontal discharge pipe will be, that… 11 17525 |