Browse Forums Eco Living Re: Need advice on our rainwater collection and storage syst 63Jun 19, 2014 7:58 am Build thread http://tinyurl.com/llgc7yk Re: Need advice on our rainwater collection and storage syst 65Jun 25, 2014 11:31 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: Need advice on our rainwater collection and storage syst 66Jun 25, 2014 11:35 pm SaveH2O A summary can be invaluable and John is to be commended for posting the feedback. This thread’s wet system was designed for John’s situation and location. Small modifications would be needed for other situations and areas. The following notes are for thread visitors interested in designing their own improved wet system. A smaller pipe branching off a vertical riser’s base and diverting to a low inlet provides a high velocity low restriction flow path for sediment. Flow velocity up a vertical riser is unable to do this, the reason why debris accumulates in standard wet system’s horizontal pipes. The location (Gympie) has heavy seasonal rainfall in excess of John’s needs, the reason a dedicated flush/outdoors tank is used. The house supplies tanks 1 &2 while the garage supplies tank 3. If filling priority to tanks 1 & 2 is needed, the 50 mm valves (diverted to tank 4) can be closed after the first +5 mm of rain. Rural property owners should consider having separate tanks for indoor and outdoor use and direct the best quality harvested water to the dedicated house tank. 50 mm valves were chosen so that when the tanks are full and there is heavy rain during a 1:20 Average Recurrence Interval (ARI), the inflow to all 4 tanks will be equalised as much as possible to balance the overflow pipes. Using 40 mm inlets would not have allowed this. The valve size chosen will differ with different scenarios. A low restriction inlet must be fitted a minimum of 100 mm above the bottom of the tank at the inlet’s lowest point and preferably within 75 degrees of an outlet that supplies a pump. When a low restriction inlet is used, sealed mosquito proof leaf diverters must be fitted to the downpipes to prevent larger debris entering the tank. It is a regulatory requirement that water entering a tank must pass through mesh with apertures less than 1,000 microns (1 mm) in diameter. A low restriction inlet operates with greater head pressure than water flowing up a vertical riser due to the height difference between the level of water in the tank and the height of the vertical riser. This gives the low inlet priority flow and increases the flow rate through the wet system, solving a common problem when fitting leaf diverters results in insufficient head. Because leaf diverters and sediment traps are used, the water in tank 4 is still of better quality than the water in most water tanks fed by standard wet systems. When leaf diverters and a low inlet are used, the small amount of sediment entering the wet system is flushed every rain event, eliminating the gradual build up of debris in wet system pipes. Do not use leaf diverters that have a coarse outer mesh and a finer inner mesh. These allow bird droppings and other smaller organic matter to drop through the outer mesh and then wash through the finer inner mesh. This design is known as an entrapment filter. Only use a leaf diverter that has a fine outer mesh (diversion filter). A leaf diverter also acts as an air gap to prevent the gutter back filling during a severe storm. Never fit first flush diverters to the top of wet system’s vertical risers! To do so only fills the diverter with the water retained in the riser while the first flush is still in the downpipe at the other end. Incredibly, numerous wet systems are fitted with first flush diverters at the top of vertical risers. Fitting leaf diverters to downpipes reduces the available head but a low restriction inlet increases the pipe’s flow rate, compensating for the lesser head. In John’s case, the 50 mm valves must be left open during heavy rain because the flow rate up the risers would be insufficient. This is particularly true during wind driven rain when one side of the house roof receives more rain than the other side. In this instance, only one valve may need to be left open. The water retained in John’s wet system pipes when it stops raining is the cleanest water drained from the roof. Debris retained in standard wet system pipes depletes the water of oxygen when it breaks down, creating anaerobic (devoid of oxygen) conditions because the water in the pipe cannot breathe, unlike water in a tank. When leaf diverters are fitted to downpipes, not a lot of debris flows into a wet system pipe every rainfall but if a standard wet system is only flushed a couple of times a year, the gradual debris build up can be significant. Water retained in a standard wet system pipe can be of worse quality than the first flush. Thank you for all the information. We will be going from dam water to tank and town water (old bore there too but above ground pump in 20yrs) So very appreciate of all the tips. Do you do consults on individual situations through your business? Build thread http://tinyurl.com/llgc7yk Re: Need advice on our rainwater collection and storage syst 67Jun 26, 2014 1:46 am No. Sorry. I have done so in the past but it just impacts too much on my time. I research and develop new products. I just give advice on the forum about rainwater harvesting because I have a passion for environmental management and water conservation plus I have retained the rights to a couple of rainwater harvesting products that I have developed. I also want to publicise this harvesting method whenever I can because of the number of calls I get from people with stagnant water tanks. If you are off the water grid, then you undoubtedly will have a wet system. The low inlet and sediment trap are very easy to plumb and they improve the water quality and increase yield. It really is an easy method to have. The flow calculations must be correctly worked though. In many instances, people can just have a large low inlet valve and do away with the vertical riser all together. The water flowing into the tank also oxygenates the anaerobic zone whereas water falling from a vertical riser into the tank can cause significant sediment re-suspension during heavy rain. Just start a new thread in the Eco Living sub forum, that way others will also benefit. A lot of people have already benefited from John's thread. Unfortunately, many people ask for advice and then remove photos and diagrams once they have what they want but John has posted additional photos and feedback for the benefit of others. It hasn't gone unnoticed. EDIT: Unfortunately, photos and diagrams disappeared from (probably?) all older forum threads including this one a few years ago, one of the dangers of using sites like the old Photo Bucket. 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: Need advice on our rainwater collection and storage syst 68Jun 26, 2014 8:08 am Bookmarking thanks h20 and John <!-- l --><a class="postlink-local" href="https://forum.homeone.com.au/viewtopic.php?t=62083">viewtopic.php?t=62083</a><!-- l --> Re: Need advice on our rainwater collection and storage syst 69Jul 30, 2014 10:05 am So much great information here. I read with interest about putting a header tank in the roof space to feed the toilet cisterns to save the pump and I was wondering how to size it? Re: Need advice on our rainwater collection and storage syst 70Jul 30, 2014 10:52 am Hi cjh, This is John's thread but I don't think that he will mind if I answer. Cisterns are high use low flow devices and if you can save on pump wear and tear, you are on a winner. The advantage of using a header tank over a pressure tank is that nearly the total volume of a header tank can be used before a float activates the pump whereas a pressure tank has about 35% draw down because of the bladder plus a header tank is usually cheaper. There are many float valves to choose from. You would also be wise to fit an overflow pipe. You also need to have the header tank fitted with mosquito proof mesh. If you are also considering supplying rainwater to a washing machine, just be aware that many modern washing machines have high pressure solenoids and for those that don't, the flow will still be slow from a header tank. You can have the header tank any size you like, it just depends on the space you have. Just remember that 1 litre = 1 kg. A tank with a 20 litre draw down would save about 80% of pump start/stops when supplying a cistern. For most households, this would save several thousand pump start ups every year. You will need to supply the harvested water to a second cistern valve. The Fluidmaster 400UK063 and the low pressure valve seal 242LP071 is discussed earlier in the thread. The doc below shows the optional twin cistern valve plumbing. http://www.vba.vic.gov.au/__data/assets ... sterns.pdf http://haron.com.au/fluidmaster_products.html 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: Need advice on our rainwater collection and storage syst 72Dec 30, 2014 10:51 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: Need advice on our rainwater collection and storage syst 73Jul 30, 2015 12:15 pm This might be a silly question, but is it better to have the inlet directly over the outlets or as far away as possible? Surely, there would be more turbulence below the inlets, and it'd stir up all the muck just below the outlet? I guess the good thing, would be maybe that would mean less would settle around the outlet? Or does it really matter??? Re: Need advice on our rainwater collection and storage syst 74Aug 04, 2015 1:47 pm I assume that you are referring to the tank's top meshed inlet and the tank's outlet valve that supplies the pump. Most tanks have the outlet valve fitted very low at the bottom and having the top meshed inlet above the outlet valve is not a good idea as falling water will cause sediment resuspension. The tank's meshed overflow outlet also needs to be accessible from the tank's top inlet as the overflow mesh can gum up and this also needs consideration when deciding on the best location for the top inlet, the overflow outlet and the bottom outlet valve that supplies the pump. Designing the system so that the pump is supplied by a floating intake like a WaterBoy and a supplementary low restriction inlet adds very little to the overall cost and also having a settling tank system combined with sediment traps and a TankVac overflow system will give you delivered water quality that will be in the top % of installations. Of interest, if you pour water into a glass container, you will see that the bubbles don't go down very far at all and this leads people to believe that a tank doesn't need a lot of water depth to 'cushion' the effects that falling water may have on the sediment layer. What isn't seen are the generated toroidal vortices that cause sediment resuspension when they impact on the bottom boundary layer. Toroidal (ring) vortices travel slowly but they rotate very fast to hold their shape for a long time due to rotation stabilising other motion. It is the fast rotating ring and not the vortex velocity that impacts on the sediment layer. I have linked a discussion paper below that has some photos of impacting toroidal vortices that you might find interesting. I have also linked a You Tube video that shows underwater toroidal vortices that you should enjoy watching. The first 30 seconds is a bit slow though! http://www.damtp.cam.ac.uk/lab/people/s ... alziel.pdf https://www.youtube.com/watch?v=mHyTOcfF99o 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: Need advice on our rainwater collection and storage syst 75Aug 16, 2020 10:04 am SaveH2O In many instances, people can just have a large low inlet valve and do away with the vertical riser all together. The water flowing into the tank also oxygenates the anaerobic zone whereas water falling from a vertical riser into the tank can cause significant sediment re-suspension during heavy rain. Does a low inlet valve mean that water would enter the tank via a valve toward the bottom of the tank, instead of via a vertical riser that feeds to the top of the tank? So the large low inlet valve would just need to have a filter on it? Why would anyone choose a vertical riser over a large low inlet valve? Would having a large low inlet valve increase the head and therefore water pressure? Thanks. Re: Need advice on our rainwater collection and storage syst 76Aug 16, 2020 12:51 pm Lisa06 SaveH2O In many instances, people can just have a large low inlet valve and do away with the vertical riser all together. The water flowing into the tank also oxygenates the anaerobic zone whereas water falling from a vertical riser into the tank can cause significant sediment re-suspension during heavy rain. Does a low inlet valve mean that water would enter the tank via a valve toward the bottom of the tank, instead of via a vertical riser that feeds to the top of the tank? Yes. This modification to standard wet systems replicates the Supadiverta rainwater harvesting system. Lisa06 So the large low inlet valve would just need to have a filter on it? Yes, the filter would be a good mosquito proof leaf diverter fitted to the downpipe. Fitting an additional simple wet system sediment trap that uses off the shelf fittings to capture and flush bed load also has benefit and was also learned during our initial rainwater harvesting research and development program before the Supadiverta was even thought of. Lisa06 Why would anyone choose a vertical riser over a large low inlet valve? Most plumbers and installers have minimal knowledge about rainwater harvesting best practice and simply copy what everyone else does, the reason why nearly all rainwater harvesting systems are poorly designed and sub standard. If the downpipes are diverted to a low inlet, the hydraulic inflow calculations must ensure that the system will still flow with enough capacity and a safety margin to drain the roof when the tank is full during a 1:20 Average Recurrence Interval rain event. Because vertical risers discharge into a tank from above the tank's roof, the low inlet will always operate with more minimum head than a vertical riser's constant head when the tank is full because the tank's water level is obviously always lower than the top of the vertical riser plus the flow path has less friction loss but large inlet valves are expensive and very, very few plumbers or installers know how to calculate flow rates through a smaller inlet. This of course is when all other things are equal, for example, both scenarios are fitted with mosquito proof leaf diverters at the downpipes that unfortunately result in head loss. Water entering a storage tank must first pass through mosquito proof filter mesh. Standard wet systems are often plumbed without leaf diverters which instantly makes the system sub standard but a low inlet must be fitted with a leaf diverter at the downpipe because there is no other filter before the water enters the tank. This is why all systems need to have the tank's inflow calculations done along with the tank's overflow capacity to ensure it exceeds the inflow rate during heavy rain when the tank is full. CAUTION: Rant ahead! The fact is that installers have always diverted water to the top of tanks and drawn it from the bottom whereas the best way is to do the opposite but that is not all! Questions never asked! Why are there some poly tanks that have a very low molded threaded outlet socket that is only suitable as a drain valve yet there is no higher threaded socket molded that is suitable for connecting to the pump? This forces people to connect the pump to a drain valve and draw water from the anaerobic zone? Some tanks are fitted with a drain valve and an outlet to fill a watering can but no pump outlet. Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Why are tanks optioned so that water flows into the tank through a meshed inlet that is fitted above the outlet that the pump draws water from? Why are many tanks optioned without an access hatch that allows the overflow mesh to be cleaned? Why are customers not told the tank's overflow capacity and why don't the tank manufacturers even know? Why do you even need an overflow pipe, why not eliminate the overflow pipe and only fill the tank to a predetermined height that will also increase the tank's capacity? Why do many of the slimline poly tanks supplied to unsuspecting customers still have designs that make desludging the bottom near impossible? Why are first flush diverters fitted at the top of vertical risers when the first flush will still be in the downpipe at the end of the wet system when if first rains? Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Why do installers invariably install submersible pumps directly on the tank's floor when many pumps suction water in from near the bottom of the pump even though it is often against the terms and conditions of warranty? Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Why do installers fit overflow pipes without expansion joints when the tank sits on reactive ground? Why do installers fit a pump's suction hose to a 90 degree elbow fitted directly to the pump? Why do installers fit the pump to the tank that the water is diverted to when there is more than one tank that would otherwise allow having a superior settling system? Why do installers fit powerful pumps with small supply pipes when they are only supplying slow fill short duration end fixtures like toilet cisterns and washing machines. viewtopic.php?f=35&t=61588&p=956938&hilit=bucket#p956938 Lisa06 Would having a large low inlet valve increase the head and therefore water pressure? Yes. The head will also vary with the tank's changing water level but a leaf diverter has to be fitted. NOTE: This isn't a regulatory requirement in many areas but it should be. Having an additional low restriction inlet valve also supplements a wet system's flow rate if still used in conjunction with a vertical riser but if you can do away with the vertical riser altogether, then it saves on material and labour costs plus it is neater. It also confuses everyone! Note that the tanks below are fed by our Supadiverta system, it is the same flow path except that the downpipes remain intact as does the storm water system. The tanks are not fitted with overflow pipes because the Supadivertas will only divert water to a pre determined level in the tank. This also gives additional storage capacity. Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Once you know the basics, the rest is easy. Read my post in the thread linked below. viewtopic.php?p=1919271#p1919271 2 19473 18 90373 DIY, Home Maintenance & Repair But if it is a ground level open pit, then it is not a charged system. No surprises there. The pipes have obviously been altered and there would be a reason for this.… 3 31235 |