spacesailor Posted November 23, 2019 Posted November 23, 2019 "I don't think we got nowhere; I certainly was prompted to research a few things, and the results are already on their way for other people to follow up on. " I decided after reading lots of comment on This site, To go to Bunnings & get "rain diverters" for my house. Not only saves the water (onto the garden) but also slows the rush of water into the creeks by a few minutes, Hopefully. My contribution to the, None man made global warming. spacesailor 1
Thruster88 Posted November 23, 2019 Posted November 23, 2019 "I don't think we got nowhere; I certainly was prompted to research a few things, and the results are already on their way for other people to follow up on. " I decided after reading lots of comment on This site, To go to Bunnings & get "rain diverters" for my house. Not only saves the water (onto the garden) but also slows the rush of water into the creeks by a few minutes, Hopefully. My contribution to the, None man made global warming. spacesailor But Spacesailer by choosing to irrigate your property instead of allowing the water to flow into the creek you may be harming the local frog population.??? If all your neighbours adopt a similar management plan the environment may suffer irrevocable damage. 1 1
Thruster88 Posted November 23, 2019 Posted November 23, 2019 The NSW RFS site is showing 5 new fires in the wilderness north west of Sydney this afternoon most likely a result of lightening. Hopefully the large air tankers can nip them in the bud. The 737 has flown some very interesting missions in the last day or so. N138CG see it on Flightradar24. 1
skippydiesel Posted November 23, 2019 Posted November 23, 2019 The NSW RFS site is showing 5 new fires in the wilderness north west of Sydney this afternoon most likely a result of lightening. Hopefully the large air tankers can nip them in the bud. A fire in this particular " wilderness" at about this time of year, back in I think 2000, erupted into an emergency - crossed Burragorang Lake and travelled east towards The Oaks. Took out some dwellings, lots of fences and bush on or about Christmas day- so much for "watch and act".
spacesailor Posted November 24, 2019 Posted November 24, 2019 The gardens can only take so much water, the rest goes on it's merry way, but later than the house runoff, that was the norm,. So making the deluge spread out over a longer time frame. All new housing here has to have water retaining pits, to help stop the deluge that causes the bad flooding of old. spacesailor
turboplanner Posted November 24, 2019 Posted November 24, 2019 All new housing here has to have water retaining pits, to help stop the deluge that causes the bad flooding of old. spacesailor Well that's the retarding basin concept; another subject for a wet year. The theory is each property holds the bulk of its runoff and lets it flow down over days rather than hours and the rivers and drains don't overcap. To do that in Victoria you need a dam about 65% of the house/shed size; no one has that; abject fail onjce the wet seasons come.
spacesailor Posted November 24, 2019 Posted November 24, 2019 My theory is the rain, (like Spain) goes firstly down the drain & the retarded water does the catch-up. spacesailor.
Methusala Posted November 24, 2019 Posted November 24, 2019 Is this the "story of decade"? I think that it is not unreasonable to label this story, linked below, as, "The story of the decade". https://www.abc.net.au/news/2019-11-24/10-years-of-climate-change-inertiaand-the-role-of-andrew-robb/11726072 1
turboplanner Posted November 24, 2019 Posted November 24, 2019 Is this the "story of decade"? No, there are better stories than that.
Methusala Posted November 24, 2019 Posted November 24, 2019 Goldilocks and the 3 bears... Maybe, but the one by Ms Crabb is no fairy tale. 1
facthunter Posted November 24, 2019 Posted November 24, 2019 Stormwater from rooves and roads runs off faster than when the place was naturally wooded,/grassed so any retardation would be a return to the earlier situation rather than something new. Local flooding would occur less often.. More water would soak into the ground in an au naturelle situation. Less soil compaction gutters and paved areas. Nev 1
turboplanner Posted November 24, 2019 Posted November 24, 2019 Stormwater from rooves and roads runs off faster than when the place was naturally wooded,/grassed so any retardation would be a return to the earlier situation rather than something new. Local flooding would occur less often.. More water would soak into the ground in an au naturelle situation. Less soil compaction gutters and paved areas. Nev Got to your bathroom, turn the taps on in your basin, leaving the plug out. Notice that the basin is slowly filling, turn the taps off befor the basin overflows. A retarding basin takes time to fill rather than flowing the full stormwater force down the waterways, but it is only delaying the inevitable. When it's full the full stormwater force flows. It's one of the two most dangerous flood control methods in the world. In Melbourne there is a series of 22 basins coming down from the Dandenongs. If the top one overflows they go down like a pack of cards, and the people below are flooded out.
facthunter Posted November 24, 2019 Posted November 24, 2019 So A Flood mitigation Dam does no good at all? IF you fill your tank THAT amount of water is then out of the equation and might as well have never fallen as rain as far as the normal river that drained the area is concerned. Urban areas don't retard as much water as the original wooded area did . Stormwater drains get water way quickly to SOMEWHERE ELSE. so downstream gets a rapid rising floodwater . Farm dams fill then what is extra passes downstream. That's why they are not welcome in water catchment areas . Nev 1
turboplanner Posted November 25, 2019 Posted November 25, 2019 So A Flood mitigation Dam does no good at all? IF you fill your tank THAT amount of water is then out of the equation and might as well have never fallen as rain as far as the normal river that drained the area is concerned. Urban areas don't retard as much water as the original wooded area did . Stormwater drains get water way quickly to SOMEWHERE ELSE. so downstream gets a rapid rising floodwater . Farm dams fill then what is extra passes downstream. That's why they are not welcome in water catchment areas . Nev To retain stormwater on the property, the basin needs to be 65% of the area of the hardstand (impervioujs house, sheds, concrete b y about 3 metres deep. No one in the urban area sets aside that much area as a retarding basin. On the bigger scale, If you were designing an estate for 1100 houses, I would think you would calculate 100% of the estate area as receiving rainfall plus whatever the overland flow had been estimated to be from the nearby mountains. You might be as surprised as I was to find the developer calculation was 0.0355% of the estate area. With that little water spout there was no problem getting planning approval. In other words I'm talking a huge shortfall in retarding capacity rather than the mild situation you described. 1
facthunter Posted November 25, 2019 Posted November 25, 2019 Wherever you get this stuff it's not written in stone and can't be universally applied with any guarantees. In principle any bit helps .Soil compaction, tarred roads roofs all worsen the problem, of quick and excessive surface run off, so called Flash flooding.. Always happens in poorly designed urban /city areas when localised, heavy and short term downpours happen. In the Country known flooding areas were well known by the locals. Once the area gets developed, Supermarkets and big houses etc are erected in these flood areas and the natural creeks swamps and watercourses disappear . What would sensible people EXPECT to be the result? Nev 1
turboplanner Posted November 25, 2019 Posted November 25, 2019 What would sensible people EXPECT to be the result? Nev There can be several generations of money- makers between the original developers who buy farmland, the next generation who buy it and subdivide it, then the builders who buy lots then the new residents who are not aware they are in a swamp or on a flood plain. There are hundreds of houses going up around Koo Wee Rup, houses all built on the ground, flood level plaque in the main street with the line at my shoulders. 1
Old Koreelah Posted November 25, 2019 Posted November 25, 2019 ...Soil compaction, tarred roads roofs all worsen the problem, of quick and excessive surface run off, so called Flash flooding.. Always happens in poorly designed urban /city areas when localised, heavy and short term downpours happen... Sadly true, Nev. Modern tiny suburban blocks shed almost all their rainwater. The piddly little tanks allowed in urban areas would make little difference. ...In the Country known flooding areas were well known by the locals. Once the area gets developed, Supermarkets and big houses etc are erected in these flood areas and the natural creeks swamps and watercourses disappear... Nev I doubt it was ever as ideal as that. Even in small country towns there was always someone who'd sell flood-prone land to the unsuspecting. Even today, I'm amazed to see new homes being built a poofteenth above the last flood level. Trees are still being removed from catchments. The regular news reports of disastrous landslides, flash floods and mudslides are just confirmation of how people value the dollar ahead of human life.
turboplanner Posted November 25, 2019 Posted November 25, 2019 Not everyone gets away. IBAC started a three week investigation into the City of Casey a week ago, the Age is following it with daily reports; would take your breath away.
Yenn Posted November 25, 2019 Posted November 25, 2019 The Wyvenhoe dam NW of Brisbane was designed as a flood mitigation dam. The idea being that when they got the tail end of a cyclone, the dam would fill and reduce downstream flooding. Then they got to realise that Brisbane needed more water, so they didn't let the level drop in dry times. Next they have a big rain event and the worst ever flooding of Brisbane. It was a good idea until the experts got involved. Urban areas produce more rapid runoff and engineers well know how to calculate it to provide drainage to deal with the flows, but we have so much urban areas now that it is a massive problem. 1 1
facthunter Posted November 25, 2019 Posted November 25, 2019 TOO many Cooks spoil the broth. It can't be a flood mitigator and a significant reserve of water at the same time.. Nev
spacesailor Posted November 25, 2019 Posted November 25, 2019 There's a report, A Queensland river has been dammed, stopping water going downstream to the Darling River. ( diverted for use of cotton farming) spacesailor
turboplanner Posted November 25, 2019 Posted November 25, 2019 There's a report, A Queensland river has been dammed, stopping water going downstream to the Darling River. ( diverted for use of cotton farming) spacesailor There are quite a few cases of illegal water harvesting. Former Federal Police Commissioner Mick Kelty has been appointed to take action agains illegal water use.
pmccarthy Posted November 25, 2019 Posted November 25, 2019 We have three tanks catching water off a large house and two sheds. Management of them is a huge problem, they are empty when needed and full when it rains. my wife despairs of watering the garden.
Methusala Posted November 26, 2019 Posted November 26, 2019 There are quite a few cases of illegal water harvesting. Former Federal Police Commissioner Mick Kelty has been appointed to take action agains illegal water use.
Recommended Posts