7 ms·

Collecting rainwater on the building roofs is a right solution, also putting the trees on these roofs. And of course, desalinating - a lot of the cities from th

by xvilka 7y ago

Collecting rainwater on the building roofs is a right solution, also putting the trees on these roofs. And of course, desalinating - a lot of the cities from the red zone are nearby seas or oceans.

fucking_tragedy 7y ago
Water rights are going to be increasingly important as time goes on, and those rights might prevent certain areas from collecting rainwater and runoff.
- imglorp 7y ago
  Already in some places. Roofcrime is a thing. http://www.ncsl.org/research/environment-and-natural-resources/rainwater-harvesting.aspx http://www.ncsl.org/research/environment-and-natural-resourc...
jedberg 7y ago
Many states ban the collection of rainwater. In California for example it was illegal until 2012. I don't about the rest of the world, but I suspect water rights can be complicated everywhere. It will be up to the states and national governments' to fix this with legislation.
monocasa 7y ago
And here in the states there's bans on collecting rainwater on state by state basis, despite the fact that there's good data that it doesn't matter to the macro hydro systems if people collect rainwater. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3948194/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3948194/ In South America it's even crazier. Bolivia was forced to privatize their water system as part of the neoliberal polices they needed to enact in order to get a world bank loan. That new company banned rainwater collection and has used heavily armed paramilitaries to enforce it.
- mrec 7y ago
  > despite the fact that there's good data that it doesn't matter to the macro hydro systems if people collect rainwater There's an interesting comment below suggesting that bans may be more about preventing mosquito breeding grounds than capturing water supply.
  - monocasa 7y ago
    Here in CO at least it's 100% a water rights thing. They're afraid of downstream lack of water if everyone is collecting their runoff (and afraid that the smaller farmers won't need to buy as much if they're collecting their own).
    - davidw 7y ago
      > Here in CO Spelling out places might be helpful in a forum that is global. To me, CO means * Colombia, the country. I don't know much about water rights, usage and distribution there. * Colorado, the US state. Certainly a place where water rights are a hot topic. * Central Oregon, where I live, where it is also very dry and water makes or breaks farm and ranch operations. * Province of Como, abbreviated CO on license plates in Italy. Water isn't quite so contested there as far as I know.
      - monocasa 7y ago
        Colorado
      - jacobsenscott 7y ago
        Colorado I think. We need to put our rain barrels behind the house so the g-man (government man) doesn't see it.
        AWildC182 7y ago
        IIRC they were made legal explicitly around 2016 and were never actually illegal in any meaningful way.
mjmahone17 7y ago
If a place gets less than 40cm of rain per year, adding water collection for the entire roof of a 100 sq meters building will only result in 40 cubic meters of water, or 40000 liters. At 100 liters per day usage (lower than a typical European), collecting rainwater gives you 40 days of usage, and in reality much less due to evaporation and other inefficiencies. What is needed most are laws preventing, or at least disincentivizing, taking more out than what is coming in. Of course this is really hard: water systems don’t follow neat political boundaries, so one entity drilling deeper or damming a river also drains the water of its neighbors.
- leereeves 7y ago
  > If a place gets less than 40cm of rain per year, adding water collection for the entire roof of a 100 sq meters building will only result in 40 cubic meters of water, or 40000 liters. At 100 liters per day usage (lower than a typical European), collecting rainwater gives you 40 days of usage, 40000/100 = 400 days of usage.
  - mjmahone17 7y ago
    Woah bad math on my part. This is a good point, and changes my view on the viability of rainwater collection.
fooblitzky 7y ago
Desalination on a scale sufficient for a city requires an extraordinary amount of power. The plant in Queensland uses: "...around 3.58 kilowatt-hours (kWh) of electricity for every cubic metre (kilolitre) of water it produces"[1] That's not going to be affordable for many poorer countries. It's expensive enough that Queensland only turns that plant on for emergencies. The CO2 emissions would also only intensify the problem. [1] https://en.wikipedia.org/wiki/Gold_Coast_Desalination_Plant https://en.wikipedia.org/wiki/Gold_Coast_Desalination_Plant
- Retric 7y ago
  That sounds much worse than it is. Outside of farming a cubic meter is a lot of water. Desalination costs ~3$ per 1,000 gallons of which around 40% is electricity costs, that’s generally affordable for most areas based on consumption and local economic conditions. Though again, not for farming.
  - thaumaturgy 7y ago
    Which source are you using for that number?
    - dmurray 7y ago
      The numbers quoted for the Queensland plant referenced above would translate to about A$1.50, or US$1, for a thousand gallons. (10c/kWh for electricity according to [0]) There are running costs other than electricity, but it's always talked about as being power-intensive, so it seems fair to assume the cost of electricity dominates. $1 for a thousand gallons seems like a non issue for domestic use in developed countries. It's on par with the cheapest rates consumers currently pay in Europe, while some countries pay 8x more [1]. Even in most poor countries it should be attainable. [0]https://www.aemc.gov.au/energy-system/electricity/electricity-market/spot-and-contract-markets https://www.aemc.gov.au/energy-system/electricity/electricit... [1]https://www.thejournal.ie/water-charges-in-ireland-versus-europe-1789576-Nov2014/ https://www.thejournal.ie/water-charges-in-ireland-versus-eu...
    - Retric 7y ago
maximente 7y ago
rainwater on roofs is certainly a solution, but it also massively increases mosquito presence if not properly set up and cared for - like, weekly. it's an externality that can't be hand-waved away as trivial when considering massive adoption of rain barrels.
- singularity2001 7y ago
  curious: what does properly setting up and caring for entail?
  - m4x 7y ago
    This link suggests you "just" need to make sure all openings in the tank are sealed and the inlet is protected with a fine mesh grille: https://www1.health.gov.au/internet/publications/publishing.nsf/Content/ohp-enhealth-raintank-cnt-l~ohp-enhealth-raintank-cnt-l-5~ohp-enhealth-raintank-cnt-l-5.5 https://www1.health.gov.au/internet/publications/publishing....
    - carapace 7y ago
      Or toss a few guppies or goldfish in there.
      - prawn 7y ago
        That'd work in the tank (besides the fish excretions) but in a wet system, you have standing water in downpipes the diameter of a tennis ball that might get a little restrictive for fish.
  - prawn 7y ago
    You'd need all intakes (e.g., downpipes from gutters) to be protected with mesh, the tank itself to have likewise, but the most painful bit is handling those intakes/overflows getting blocked by leaves/debris. My pipes get blocked by leaves even without mesh. There are a variety of angled mesh systems you can use but adding them to each down-pipe gets expensive.

by xvilka 7y ago

Collecting rainwater on the building roofs is a right solution, also putting the trees on these roofs. And of course, desalinating - a lot of the cities from the red zone are nearby seas or oceans.

fucking_tragedy 7y ago

Water rights are going to be increasingly important as time goes on, and those rights might prevent certain areas from collecting rainwater and runoff.

imglorp 7y ago
Already in some places. Roofcrime is a thing. http://www.ncsl.org/research/environment-and-natural-resources/rainwater-harvesting.aspx http://www.ncsl.org/research/environment-and-natural-resourc...

jedberg 7y ago

Many states ban the collection of rainwater. In California for example it was illegal until 2012. I don't about the rest of the world, but I suspect water rights can be complicated everywhere. It will be up to the states and national governments' to fix this with legislation.

monocasa 7y ago

And here in the states there's bans on collecting rainwater on state by state basis, despite the fact that there's good data that it doesn't matter to the macro hydro systems if people collect rainwater. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3948194/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3948194/ In South America it's even crazier. Bolivia was forced to privatize their water system as part of the neoliberal polices they needed to enact in order to get a world bank loan. That new company banned rainwater collection and has used heavily armed paramilitaries to enforce it.

mrec 7y ago
> despite the fact that there's good data that it doesn't matter to the macro hydro systems if people collect rainwater There's an interesting comment below suggesting that bans may be more about preventing mosquito breeding grounds than capturing water supply.
- monocasa 7y ago
  Here in CO at least it's 100% a water rights thing. They're afraid of downstream lack of water if everyone is collecting their runoff (and afraid that the smaller farmers won't need to buy as much if they're collecting their own).
  - davidw 7y ago
    > Here in CO Spelling out places might be helpful in a forum that is global. To me, CO means * Colombia, the country. I don't know much about water rights, usage and distribution there. * Colorado, the US state. Certainly a place where water rights are a hot topic. * Central Oregon, where I live, where it is also very dry and water makes or breaks farm and ranch operations. * Province of Como, abbreviated CO on license plates in Italy. Water isn't quite so contested there as far as I know.
    - monocasa 7y ago
      Colorado
    - jacobsenscott 7y ago
      Colorado I think. We need to put our rain barrels behind the house so the g-man (government man) doesn't see it.
      - AWildC182 7y ago
        IIRC they were made legal explicitly around 2016 and were never actually illegal in any meaningful way.

mjmahone17 7y ago

If a place gets less than 40cm of rain per year, adding water collection for the entire roof of a 100 sq meters building will only result in 40 cubic meters of water, or 40000 liters. At 100 liters per day usage (lower than a typical European), collecting rainwater gives you 40 days of usage, and in reality much less due to evaporation and other inefficiencies. What is needed most are laws preventing, or at least disincentivizing, taking more out than what is coming in. Of course this is really hard: water systems don’t follow neat political boundaries, so one entity drilling deeper or damming a river also drains the water of its neighbors.

leereeves 7y ago
> If a place gets less than 40cm of rain per year, adding water collection for the entire roof of a 100 sq meters building will only result in 40 cubic meters of water, or 40000 liters. At 100 liters per day usage (lower than a typical European), collecting rainwater gives you 40 days of usage, 40000/100 = 400 days of usage.
- mjmahone17 7y ago
  Woah bad math on my part. This is a good point, and changes my view on the viability of rainwater collection.

fooblitzky 7y ago

Desalination on a scale sufficient for a city requires an extraordinary amount of power. The plant in Queensland uses: "...around 3.58 kilowatt-hours (kWh) of electricity for every cubic metre (kilolitre) of water it produces"[1] That's not going to be affordable for many poorer countries. It's expensive enough that Queensland only turns that plant on for emergencies. The CO2 emissions would also only intensify the problem. [1] https://en.wikipedia.org/wiki/Gold_Coast_Desalination_Plant https://en.wikipedia.org/wiki/Gold_Coast_Desalination_Plant

Retric 7y ago
That sounds much worse than it is. Outside of farming a cubic meter is a lot of water. Desalination costs ~3$ per 1,000 gallons of which around 40% is electricity costs, that’s generally affordable for most areas based on consumption and local economic conditions. Though again, not for farming.
- thaumaturgy 7y ago
  Which source are you using for that number?
  - dmurray 7y ago
    The numbers quoted for the Queensland plant referenced above would translate to about A$1.50, or US$1, for a thousand gallons. (10c/kWh for electricity according to [0]) There are running costs other than electricity, but it's always talked about as being power-intensive, so it seems fair to assume the cost of electricity dominates. $1 for a thousand gallons seems like a non issue for domestic use in developed countries. It's on par with the cheapest rates consumers currently pay in Europe, while some countries pay 8x more [1]. Even in most poor countries it should be attainable. [0]https://www.aemc.gov.au/energy-system/electricity/electricity-market/spot-and-contract-markets https://www.aemc.gov.au/energy-system/electricity/electricit... [1]https://www.thejournal.ie/water-charges-in-ireland-versus-europe-1789576-Nov2014/ https://www.thejournal.ie/water-charges-in-ireland-versus-eu...
  - Retric 7y ago

maximente 7y ago

rainwater on roofs is certainly a solution, but it also massively increases mosquito presence if not properly set up and cared for - like, weekly. it's an externality that can't be hand-waved away as trivial when considering massive adoption of rain barrels.

singularity2001 7y ago
curious: what does properly setting up and caring for entail?
- m4x 7y ago
  This link suggests you "just" need to make sure all openings in the tank are sealed and the inlet is protected with a fine mesh grille: https://www1.health.gov.au/internet/publications/publishing.nsf/Content/ohp-enhealth-raintank-cnt-l~ohp-enhealth-raintank-cnt-l-5~ohp-enhealth-raintank-cnt-l-5.5 https://www1.health.gov.au/internet/publications/publishing....
  - carapace 7y ago
    Or toss a few guppies or goldfish in there.
    - prawn 7y ago
      That'd work in the tank (besides the fish excretions) but in a wet system, you have standing water in downpipes the diameter of a tennis ball that might get a little restrictive for fish.
- prawn 7y ago
  You'd need all intakes (e.g., downpipes from gutters) to be protected with mesh, the tank itself to have likewise, but the most painful bit is handling those intakes/overflows getting blocked by leaves/debris. My pipes get blocked by leaves even without mesh. There are a variety of angled mesh systems you can use but adding them to each down-pipe gets expensive.