Rainwater Catchment systems in Hawaii

[Mauna Kea Cloudforest]

This is a great question for folks in Hawaii. Due to the California drought, we installed a major rainwater catchment system. Our tanks are full, and for the most part I had been using sump pumps to water the garden. But now we want to disconnect the house water from the garden due to the heavy water restrictions and run the irrigation system entirely from our water harvesting system. The garden needs to be 100% independent from city water, that's our goal. What sort of pumps do folks in Hawaii use, and what's the best filtering system available? I've been looking at Grunfos pumps, which provide water pressure on demand, but I am curious what folks on the East side of the Big Island generally use. And what would be the best filtering system?

[_Keith]

Well, I don't live in Hawaii, but this little pump is cheap and capable. My neighbor has one on each of his 2 cisterns and uses them daily.

https://www.waynepumps.com/solution-center/utility-pumps-transfer/pc2

I suspect other people, not even from Hawaii might have some experience with such things.

[Mauna Kea Cloudforest]

Keith, the idea is to get 40-60 PSI on demand from the catchment tanks. In other words, you go to the garden hose faucet, and you open it, and pressure is generated on demand. Same with the automated drip system which requires 40-60 PSI input. You can't do that with that pump. The pump you show would actually be good for my gray water system.

[_Keith]

Keith, the idea is to get 40-60 PSI on demand from the catchment tanks. In other words, you go to the garden hose faucet, and you open it, and pressure is generated on demand. Same with the automated drip system which requires 40-60 PSI input. You can't do that with that pump. The pump you show would actually be good for my gray water system.

Not arguing on your needs, but why that much PSI? Neighbor uses it on his drip systems and is more than adequate for the GPH of his need over quite a large area. I was thinking of using them as well, so am curious was to why you need this much PSI.

[_Keith]

Keith, the idea is to get 40-60 PSI on demand from the catchment tanks. In other words, you go to the garden hose faucet, and you open it, and pressure is generated on demand. Same with the automated drip system which requires 40-60 PSI input. You can't do that with that pump. The pump you show would actually be good for my gray water system.

Not arguing on your needs, but why that much PSI? Neighbor uses it on his drip systems and is more than adequate for the GPH of his need over quite a large area. I was thinking of using them as well, so am curious was to why you need this much PSI.

Also, his cisterns, as are all local cisterns are above ground which increases pressure as well.

[Jerry@TreeZoo]

If you want pressure on demand you are going to need a pump with a pressure switch and an air bladder tank to keep the motor from constant cycling. That is what is used for a well pump system.

Much simpler to just have a pump with an on/off switch by your hose bib.

[Mauna Kea Cloudforest]

The irrigation system uses orbit manifolds on a pvc network. These manifolds expect 40-60 psi. I don't want to manually have to run a pump and manually distribute water, that's the whole point.

[redant]

The irrigation system uses orbit manifolds on a pvc network. These manifolds expect 40-60 psi. I don't want to manually have to run a pump and manually distribute water, that's the whole point.

Then you will need to go with Jerry's first suggestion, it's whats used for well water systems.

[Mauna Kea Cloudforest]

The irrigation system uses orbit manifolds on a pvc network. These manifolds expect 40-60 psi. I don't want to manually have to run a pump and manually distribute water, that's the whole point.

Then you will need to go with Jerry's first suggestion, it's whats used for well water systems.

Yes, same pump system as for rain catchment and well systems with storage tanks. And I was asking for advice on which models of pumps people use. That's what the Grunfos pump is that I mentioned in my first post. It's the most common pump around.

[MattyB]

Are you talking about the Orbit manifolds that run drip irrigation? Aren't those spec'd to run off of 25psi max.?

[Mauna Kea Cloudforest]

Are you talking about the Orbit manifolds that run drip irrigation? Aren't those spec'd to run off of 25psi max.?

Not the adjustable flow manifolds, those are designed to replace sprinkler heads on regular PVC with >40PSI.

[LJG]

Have you calculated how much water you need to run your irrigation and how much is produced by the catchment system? Maybe run a bypass before you completely cut yourself off from city water. What if you get no rain for a month? You are lucky, I would love to supplement my water with free RO water but where I live it is a waste of money. We just don't get the rain.

A friend of mine (not a palm guy) put in a 500 gallon system. Cost him a fortune. He posted on FB how proud he was. Only after wasting the money did he realize he averaged 5 units a month for irrigation. That's around 3700 gallons a month. Considering it doesn't rain here in San Diego, he blows through the 500 gallons in a few quick waterings and won't recharge sometimes for 6 months depending on the year here.

[Mauna Kea Cloudforest]

I agree, Len, before anyone puts in such a system, you have to weight the cost/benefit balance, and you can only determine that if you have a good sense for the annual flow rate. I did such an analysis for my system and it comes out very positive.

I have not done such an analysis for Southern California where flow is zero for six to nine months of the year. But it's not hard to do. Here are some additional benefits you may not be thinking of.

The goal of such a system isn't to store water for the dry season. As you correctly pointed out, 500 gallons in your friend's case or even 5,000 gallons would only cover about 1 - 2 months of dry season for the average garden. It's a nice side benefit to cover at least two months of dry season watering needs, but this represents only a small fraction of the benefits you get from such a system. Given how dry Winters are in Southern California, there is a major benefit into achieving total garden soil saturation during the Winter months. A tank system should be designed to be capable of storing a day's worth of heavy rain. After a heavy rain, you need to have an adequate pump system that can distribute the water via the irrigation system into the entire yard and leave the tank empty so that the next storm can fill it up again.

Now the Winter irrigation needs are slightly different than Summer irrigation needs. In the Winter, you want to achieve maximum saturation over large surfaces, so the Winter irrigation system preferably is an above-ground, above mulch system that distributes the water evenly across the soil surface. In my garden, the Winter irrigation system consists of above-ground sprinklers and leach field pipes. Since I am on a hillside, the leach field pipes are very effective in distributing the water. In contrast, the Summer irrigation system is drip/micro-sprinkler based and delivers the water only to the plants.

If the water saturates the soil, all you have to do is make sure the soil is "sealed" by renewing the mulch cover after the last late Winter storm. This will easily buy you a solid 2 months before you have to turn on the dry season irrigation system.

In your friend's system, I suspect a 500 gallon tank is wholly inadequate because the average roof footprint is around 1,500 square feet. 1 square feet represents 144 square inches, so one inch of rain on a 1,500 sqft roof gives you 1,500 x 144 = 216,000 cubic inches of water. One US gallon is 231 cubic inches. This means one inch of rain falling on the average roof generates 935 gallons of water. I would design a tank that can handle at least two inches of rain. If you add your driveway, patios and sidewalks, the tank needs go up even further and you get even more water. The benefits are enormous!

A properly designed system with at least a storm's worth of water capacity can saturate your garden, replenish the ground water table and provide you with at least two extra months of not having to turn on the irrigation provided you mulch your garden. Add to that the capacity to handle two more months of dry season irrigation, you're left with only 2 months to use city water. That's really pretty good.

Recapping all the benefits:

• 4 months of using city watering during the dry season is eliminated
• All wet season irrigation is eliminated
• Garden is saturated, providing fantastic palm growth on cool growing species
• Aquifer is replenished instead of running water into the storm drains

But wait, that's not all:

• You could actually cultivate oyster or shiitake in your mulch during the Winter!
• Soil microflora and microfauna flourishes

Tanks cost around $700-$1200 depending on size, the pump is around $600, pressure tank is $200, switches, piping and misc. add another $500, so for a DIY system, you're spending about $2,000. I don't know how cheap water is down south, but up here, it's a no-brainer.

[Kim]

Your question is framed around what people use in East Hawaii, but our usage is entirely different. Water catchment in East Hawaii is for household use, not for irrigation. As such the standard for filtering is very high. My system uses 2 filters (a 10 micron and a 5 micron) to remove silt and other impurities plus a UV filter to kill any micro-organisms that might be in the water. After all, I'm going to drink it. A typical tank holds 10,000 gallons and it is very rare to have a tank go empty from lack of rain, but I'm told it has happened. Then the homeowner has to pay for water delivery by truck.

Nature provides the irrigation.

[Zeeth]

I agree, Len, before anyone puts in such a system, you have to weight the cost/benefit balance, and you can only determine that if you have a good sense for the annual flow rate. I did such an analysis for my system and it comes out very positive.

I have not done such an analysis for Southern California where flow is zero for six to nine months of the year. But it's not hard to do. Here are some additional benefits you may not be thinking of.

The goal of such a system isn't to store water for the dry season. As you correctly pointed out, 500 gallons in your friend's case or even 5,000 gallons would only cover about 1 - 2 months of dry season for the average garden. It's a nice side benefit to cover at least two months of dry season watering needs, but this represents only a small fraction of the benefits you get from such a system. Given how dry Winters are in Southern California, there is a major benefit into achieving total garden soil saturation during the Winter months. A tank system should be designed to be capable of storing a day's worth of heavy rain. After a heavy rain, you need to have an adequate pump system that can distribute the water via the irrigation system into the entire yard and leave the tank empty so that the next storm can fill it up again.

Now the Winter irrigation needs are slightly different than Summer irrigation needs. In the Winter, you want to achieve maximum saturation over large surfaces, so the Winter irrigation system preferably is an above-ground, above mulch system that distributes the water evenly across the soil surface. In my garden, the Winter irrigation system consists of above-ground sprinklers and leach field pipes. Since I am on a hillside, the leach field pipes are very effective in distributing the water. In contrast, the Summer irrigation system is drip/micro-sprinkler based and delivers the water only to the plants.

If the water saturates the soil, all you have to do is make sure the soil is "sealed" by renewing the mulch cover after the last late Winter storm. This will easily buy you a solid 2 months before you have to turn on the dry season irrigation system.

In your friend's system, I suspect a 500 gallon tank is wholly inadequate because the average roof footprint is around 1,500 square feet. 1 square feet represents 144 square inches, so one inch of rain on a 1,500 sqft roof gives you 1,500 x 144 = 216,000 cubic inches of water. One US gallon is 231 cubic inches. This means one inch of rain falling on the average roof generates 935 gallons of water. I would design a tank that can handle at least two inches of rain. If you add your driveway, patios and sidewalks, the tank needs go up even further and you get even more water. The benefits are enormous!

A properly designed system with at least a storm's worth of water capacity can saturate your garden, replenish the ground water table and provide you with at least two extra months of not having to turn on the irrigation provided you mulch your garden. Add to that the capacity to handle two more months of dry season irrigation, you're left with only 2 months to use city water. That's really pretty good.

Recapping all the benefits:

• 4 months of using city watering during the dry season is eliminated
• All wet season irrigation is eliminated
• Garden is saturated, providing fantastic palm growth on cool growing species
• Aquifer is replenished instead of running water into the storm drains

But wait, that's not all:

• You could actually cultivate oyster or shiitake in your mulch during the Winter!
• Soil microflora and microfauna flourishes

Tanks cost around $700-$1200 depending on size, the pump is around $600, pressure tank is $200, switches, piping and misc. add another $500, so for a DIY system, you're spending about $2,000. I don't know how cheap water is down south, but up here, it's a no-brainer.

Interesting analysis Axel. In my area of Florida, we have enough rain to sustain most palms (about 50 inches per year) if it was spread out evenly throughout the year. The problem is that about 60% of that falls in summer, with the spring winter and autumn being very dry, and our sand doesn't hold water at all. I bet a system like you describe would work here. However, it costs about $2,000 to hire someone to dig a well and access one of the most productive aquifers in the world, so I guess it probably wouldn't make much sense to set something like that up here.

[Mauna Kea Cloudforest]

I agree, Len, before anyone puts in such a system, you have to weight the cost/benefit balance, and you can only determine that if you have a good sense for the annual flow rate. I did such an analysis for my system and it comes out very positive.

I have not done such an analysis for Southern California where flow is zero for six to nine months of the year. But it's not hard to do. Here are some additional benefits you may not be thinking of.

The goal of such a system isn't to store water for the dry season. As you correctly pointed out, 500 gallons in your friend's case or even 5,000 gallons would only cover about 1 - 2 months of dry season for the average garden. It's a nice side benefit to cover at least two months of dry season watering needs, but this represents only a small fraction of the benefits you get from such a system. Given how dry Winters are in Southern California, there is a major benefit into achieving total garden soil saturation during the Winter months. A tank system should be designed to be capable of storing a day's worth of heavy rain. After a heavy rain, you need to have an adequate pump system that can distribute the water via the irrigation system into the entire yard and leave the tank empty so that the next storm can fill it up again.

Now the Winter irrigation needs are slightly different than Summer irrigation needs. In the Winter, you want to achieve maximum saturation over large surfaces, so the Winter irrigation system preferably is an above-ground, above mulch system that distributes the water evenly across the soil surface. In my garden, the Winter irrigation system consists of above-ground sprinklers and leach field pipes. Since I am on a hillside, the leach field pipes are very effective in distributing the water. In contrast, the Summer irrigation system is drip/micro-sprinkler based and delivers the water only to the plants.

If the water saturates the soil, all you have to do is make sure the soil is "sealed" by renewing the mulch cover after the last late Winter storm. This will easily buy you a solid 2 months before you have to turn on the dry season irrigation system.

In your friend's system, I suspect a 500 gallon tank is wholly inadequate because the average roof footprint is around 1,500 square feet. 1 square feet represents 144 square inches, so one inch of rain on a 1,500 sqft roof gives you 1,500 x 144 = 216,000 cubic inches of water. One US gallon is 231 cubic inches. This means one inch of rain falling on the average roof generates 935 gallons of water. I would design a tank that can handle at least two inches of rain. If you add your driveway, patios and sidewalks, the tank needs go up even further and you get even more water. The benefits are enormous!

A properly designed system with at least a storm's worth of water capacity can saturate your garden, replenish the ground water table and provide you with at least two extra months of not having to turn on the irrigation provided you mulch your garden. Add to that the capacity to handle two more months of dry season irrigation, you're left with only 2 months to use city water. That's really pretty good.

Recapping all the benefits:

• 4 months of using city watering during the dry season is eliminated
• All wet season irrigation is eliminated
• Garden is saturated, providing fantastic palm growth on cool growing species
• Aquifer is replenished instead of running water into the storm drains

But wait, that's not all:

• You could actually cultivate oyster or shiitake in your mulch during the Winter!
• Soil microflora and microfauna flourishes

Tanks cost around $700-$1200 depending on size, the pump is around $600, pressure tank is $200, switches, piping and misc. add another $500, so for a DIY system, you're spending about $2,000. I don't know how cheap water is down south, but up here, it's a no-brainer.

Interesting analysis Axel. In my area of Florida, we have enough rain to sustain most palms (about 50 inches per year) if it was spread out evenly throughout the year. The problem is that about 60% of that falls in summer, with the spring winter and autumn being very dry, and our sand doesn't hold water at all. I bet a system like you describe would work here. However, it costs about $2,000 to hire someone to dig a well and access one of the most productive aquifers in the world, so I guess it probably wouldn't make much sense to set something like that up here.

You are very lucky that it's that cheap in Florida. I just checked, it's even cheaper than what you mention. See http://www.floridapumpservice.com/t/ShallowWellContract. I looked at purchasing acreage in the Santa Cruz Mountains to build an investment property, and the property needed a well. We checked into the cost, it runs $15K-20K to drill. The well casing and screen alone along with a pump costs well over $2K, then you need all of the infrastructure associated with rain catchment, except that you're putting well water into your tank system. This is insane, it's not a feasible and cost effective thing to do here.

[LJG]

Alex, you won't be putting in a DIY system that big for $2000. And trying to route water from all over the roof to one spot to be pumped out takes a lot of effort. But taking your numbers of almost 1000 gallons with 1 inch of rain let's look at cost. 1 U (750 gallons) of water is about $3/mo. In SoCal a rain catchment system used to replace city water has no ROI that most homeowners would be happy with. Where you are at makes more sense.

I am not trying to get people to change their mind as I think it is great you can supplement and I wish I could. But people need to do the math first and not listen to the makers of these systems. They market the hell out of them. That is how my buddy got stuck. He now just uses the water for his vegetable garden and lives with the big ugly 500 gallon tank against his house.

[Mauna Kea Cloudforest]

Alex, you won't be putting in a DIY system that big for $2000. And trying to route water from all over the roof to one spot to be pumped out takes a lot of effort. But taking your numbers of almost 1000 gallons with 1 inch of rain let's look at cost. 1 U (750 gallons) of water is about $3/mo. In SoCal a rain catchment system used to replace city water has no ROI that most homeowners would be happy with. Where you are at makes more sense.

I am not trying to get people to change their mind as I think it is great you can supplement and I wish I could. But people need to do the math first and not listen to the makers of these systems. They market the hell out of them. That is how my buddy got stuck. He now just uses the water for his vegetable garden and lives with the big ugly 500 gallon tank against his house.

True, if your water isn't already routed to a single collection point, it's going to cost more than $2K. For me it was easy because we have a number of drains that all go to the same endpoint.

[edbrown_III]

1inch /12 x 2500 ft2 roof = 208 ft3 = 1550 gallons if you catch every drop

10 inches a year is 15500 gallons this is a 45 foot diameter pool with a 6 foot depth. you only catch a few months worth and you probably got a 31 foot pool

3000-4000 gallons if you want to have a workign system that can store and hold for a multiple rain days . 60 rain barrels or some reasonalbe fraction. 500 gallons is 3 just enough to do some manual watering with --- sump pump or bucket brigade.

hard to make the economics work other then just got water that you wouldnt already have . sometimes this is priceless.

Len and Others are right many ways of lookign at the value or economics

Best regarsds

Ed

[LJG]

Hi Ed,

Good points. One thing though is that the 10 inches of rain happens within a few months here. So you fill up the system once and might sit on that water because there is no need to water the yard. So when it does rain again, the water just runs off as the system is still full. If we got the 10 inches spread out like 1 inch a month that would be sweet

I agree that one benefit that cannot be covered under ROI is the warm fuzzy you get knowing you just got sometime you would have wasted before. When I put in my solar system it was a great feeling knowing I didn't have to pay the electric company what I was before and that I was making a positive impact on the environment. The best news was that a 15 year ROI that the solar installers had me at is turning out to be 9 years thanks to ridiculous rate increase, switching to LED and making some lifestyle changes.

[Mauna Kea Cloudforest]

When on 249 gallons per day restrictions, every single ounce of water counts. We're taking all sorts of measures as a family to stay within the allotment, because the fine is $50/unit of water over the allotment. For us, this means:

• All gray water is recycled into landscaping, basically for all alkaline compatible palms
• We use irrigation water multiple times, it gets captured from the french drains and re-used
• Most of us are showering at the gym and at work
• We're reducing laundry and dishwasher use
• And the catchment system provides priceless additional irrigation water

Anyone still want to argue about economics?

[George Sparkman]

Are the restrictions based on your past usage?

[Mauna Kea Cloudforest]

Are the restrictions based on your past usage?

Nope, just 10 units per month per household, regardless of any previous usage. Businesses are exempt, so I can watch our local golf course dump thousands of gallons per day on the golf course while residences are left to starve from lack of water. Our water district has only one reservoir running off the San Lorenzo River, and they're restricted in how much water they can hold back to preserve the river ecosystem. And many folks around here are hell bent on doing anything they can to keep desalination plants at bay. The water district 5 miles to the East of us has a massive surplus of water, but the geniuses at the water dept. can't seem to get their act together to fix this.

Worse yet is that if it's as hot this year as it was last Summer (every indication is that it will be), there may be massive wild fires, and the fire hydrants throughout much of the County are fed by the Santa Cruz water district. This has got to be the biggest water mess in the history of the State.

Worse comes to worse, I could go to friends houses who live on the main runoff stream created by the golf course runoff and tank up on water. Obviously they will not be affected from a landscape point of view.

[LJG]

Well I would put in a greenhouse and start selling plants. Now you have a business.

[Mauna Kea Cloudforest]

Well I would put in a greenhouse and start selling plants. Now you have a business.

Been there, done that. The city's reply is that they don't care if I run a business that depends on water. They only supply indoor residential water. If I want to run a business, I need to purchase a separate water meter. The cost of that meter came out to well over $20K. That's because they charge $6.5K for the meter, $6.5K for the pumping tax, and the professional contractor cost to rip up the pavement is about $7K. Oh, and that's for the smallest diameter supply, about a 2-3g/min flow, so I still would need a tank system.

When I read how much people pay for permits and things of this sort in other states, it makes me wonder how it is that Californians haven't gone on a revolt yet. It's sick what is going on in this State, it's all just legalized bribery.

Do you know how much it costs in Florida to get a building permit? Look at http://www.osceola.org/buildingoffice/114-7327-7329/residential_fees.cfm. It costs $720 to get a permit. Here in Santa Cruz County it costs $45,000 to get a permit, I kid you not.

Edit: one of the interesting factoids is that at the heart of all these policies are ardent anti-growth sentiments. The lack of water prevents additional growth, and this is what's being used to prevent the University of California from expanding the campus. The high cost of building is another effort at keeping growth down. I am pretty sure that although environmental issues are used to fight desalination, anti-growth is ultimately the main driving factor. Part of me wants to become a libertarian, but when I look around, the policies are working, there's virtually no growth and lots of beautiful vistas everywhere.

[Mauna Kea Cloudforest]

After some reflection, considering how well this county has remained as pristine as it is, my thinking is that the water rationing is a rather small price to pay for the preservation of the natural beauty surrounding us. Here's a video from 1974 which shows how little has changed here.

When I drive around in Southern California, much of its beauty is toast. I remember when San Diego North County was a just a collection of pretty coastal villages. I used to ride my bike from La Jolla to Carlsbad, and it was breathtakingly beautiful. Then they built University Town Center out in the middle of nowhere East of La Jolla and no one could figure out why. In a short period, all of it got paved over with suburbia. Heading up I-5 there was San Clemente and San Juan Capistrano and then nothing all the way up to Santa Ana except miles and miles of pristine Orange groves. All of it is gone, paved over and replaced with traffic jams and incredible crowds.

Most of what has kept Santa Barbara from exploding is also not enough water. It's still beautiful up there with miles of open space. We should keep it that way. I am going to just shut up and stop complaining about the water rationing. It's worth it.

[LJG]

Now only the rich can afford to set up businesses, buy land and build houses there. So much for that Northern California all inclusive society they believe so much in

[Mauna Kea Cloudforest]

Now only the rich can afford to set up businesses, buy land and build houses there. So much for that Northern California all inclusive society they believe so much in

Not even the rich. I've heard of guys who've bought land, sunk over $1M into it on improvements to build, but they still aren't allowed to build.

I am curious as to who the "they" is that you are referring to? The Bay area's tech industry is what drives all the prices through the roof, it's called free market economics. Just because there are more hippies up here that believe in some egalitarian utopia doesn't make Norcal any different from any other part of America. It's the same free capitalism rules that reign here as anywhere else. So you get the same byproducts. Money rules, that's the bottom line. In Hawaii, you have to be well off to own something on the Kona side unless you managed to get in before the prices went up. Same story as anywhere else. Sorry about my cynicism, but I question if humans are even capable of an egalitarian society, it doesn't seem to be part of our biology. We've got a lot of evolving to do before it will really happen.

[LJG]

I will refrain from replying as to answer your question relates to politics.

[Mauna Kea Cloudforest]

I will refrain from replying as to answer your question relates to politics.

That's wise. Hard to bring up water issues without it relating to politics. It's yet another endangered resource.

[Jerry@TreeZoo]

Water is not that rare of a resource. After all, you have the whole Pacific Ocean at your back door with all the water you could ever want. I think that desalination plants would be a cheap alternative to all the other measures and restrictions you all are going through. They have relatively inexpensive "water makers" on private yachts that are essentially just Reverse Osmosis set ups I believe. Why couldn't people just do that there? Even here in Florida with our abundant rainfall it is almost cheaper to put in a well into a salt water aquifer and run a water maker system than to hook up to a city water system and pay monthly bills.

[Zeeth]

Water is not that rare of a resource. After all, you have the whole Pacific Ocean at your back door with all the water you could ever want. I think that desalination plants would be a cheap alternative to all the other measures and restrictions you all are going through. They have relatively inexpensive "water makers" on private yachts that are essentially just Reverse Osmosis set ups I believe. Why couldn't people just do that there? Even here in Florida with our abundant rainfall it is almost cheaper to put in a well into a salt water aquifer and run a water maker system than to hook up to a city water system and pay monthly bills.

That might be kind of interesting to set up. I bet that with some solar panels installed you could run the pumps pretty cheaply as well. I know there's a garden in Miami that uses RO water for watering everything, so that might be a good way to cut costs because of how much water is wasted when you run such a system.

[edbrown_III]

you might want to price a a system ----- based upon gpm or gallons needed ---- irrigation water is in quanities a lot more than 200 gallons per day.

usually any sort of desalination or RO prices its self beynd folks reach when you get a bove a few gpm.

MHO, Best regarfds

Ed

[Kim]

Heard something on NPR this morning about using solar panels and a boiler, simple technology, for water desalination for agriculture. Maybe the concept could be adapted on a small scale.

[Jerry@TreeZoo]

http://www.cruiserowaterandpower.com/30_GPH_Water_Maker.html?gclid=CJK60pOgn74CFWNgMgod_XQAaA

A quick google gives this system of 35 gph/840 gpd of less than $5K. Add in a well and some storage tanks and electrical and plumbing costs (South Florida pricing) and it is about $10K. A year's worth of filters is $135. If you have access to an aquifer, it would pay for itself in few years. Much of it is 12V so it would be an easy solar power hookup too.

Here is a company that does the work.

http://www.watermakers.com/Residences_c_11.html

[edbrown_III]

840 gal/day isnt much water ? you still have to drill a deepeer well 800 feet or so . 5k add on is a lot to cough up on top of a 10 k well. municipal water is produced alot cheaper --- you cant just dump the brine you produced as its salt water . Uusally the brine is about 10% of the discharge i guess you dump it in the sewer if your sneaky but theirs a charge for that .

usually a well is cheaper if you have a access as municipalities are paying for treatment and distribution lines etc related to getting it to your doorstep. Treatment is cheaper unless they are doing RO or desalination.

Best regardsd

Ed

[Mauna Kea Cloudforest]

I did a simple calculation for my yard to figure out the maximum capacity. Each zone uses about 10gpm when all micro-ports are open on all manifolds. I would run them for a maximum of 60 minutes per week. That's 600 gallons per zone. 15 zones cover my entire 2/3 acre but the lawn is being converted to artificial turf, which brings us down to 14 zones, or about two zones per day. If all zones are in maximum use, I would need 1,200 gallons per day. My needs would be more than covered with 1 gallon/minute flow. But we don't even use that much. An audit of my system reveals I burn up about 7 units a month. Gray water covers at least half of that. That brings the remainder down to about 3.5 units.

[edbrown_III]

thats sort of my point 1200 gallons /day in CA ---Remember you are only producing water at 840 /day, also FLorida is sandy and soil percolates so much more . . you would have to water more for the same effect and soil saturation. This is the dilema theres only so much water to be made and pumped . you can pump more but if its salt water and you need to desalt you have a big expense and a big power bill. a 10 watt solar panel produces 10 watts and can run a small peristalt pump but not a larger pump like you would need. then you have to get rid of the salty waste that the membrane catches and disharges.

it just puts the desal RO option at the last of options to deal with getting more water unfortunately as the oceans make up so much water and the rest is just a small percentage something like 4% .

Best regards

Ed

[Sabal Steve]

Dealing with local government is stifiling here. I paid around 2K for a permit for a very small add on. But it's not the only cost - there's all of the collateral damage associated with the city. If you become involved with the costal commission, the surfrider foundation, or the historical process

, you're screwed. They can tie things up for years.

And regarding the business climate of the state - just look at Toyota and their recent move to Texas.

I haven't kept an eye on building within the UC system, but I can tell you the building on the UCSD campus has been explosive.

Well I would put in a greenhouse and start selling plants. Now you have a business.

Been there, done that. The city's reply is that they don't care if I run a business that depends on water. They only supply indoor residential water. If I want to run a business, I need to purchase a separate water meter. The cost of that meter came out to well over $20K. That's because they charge $6.5K for the meter, $6.5K for the pumping tax, and the professional contractor cost to rip up the pavement is about $7K. Oh, and that's for the smallest diameter supply, about a 2-3g/min flow, so I still would need a tank system.

When I read how much people pay for permits and things of this sort in other states, it makes me wonder how it is that Californians haven't gone on a revolt yet. It's sick what is going on in this State, it's all just legalized bribery.

Do you know how much it costs in Florida to get a building permit? Look at http://www.osceola.org/buildingoffice/114-7327-7329/residential_fees.cfm. It costs $720 to get a permit. Here in Santa Cruz County it costs $45,000 to get a permit, I kid you not.

Edit: one of the interesting factoids is that at the heart of all these policies are ardent anti-growth sentiments. The lack of water prevents additional growth, and this is what's being used to prevent the University of California from expanding the campus. The high cost of building is another effort at keeping growth down. I am pretty sure that although environmental issues are used to fight desalination, anti-growth is ultimately the main driving factor. Part of me wants to become a libertarian, but when I look around, the policies are working, there's virtually no growth and lots of beautiful vistas everywhere.