Planning for Water Contingencies

We know that fresh water is essential to life. While we can survive for weeks without food, even a few days without water can be a problem. One rule of thumb as to the amount of water needed for drinking is two quarts (1.9 liters) per person per day. If one includes uses other than drinking, obviously more is needed.

In uncertain times, the question is what, if anything, we should be doing with respect to backup planning for water. We can think about this question on both a short term and longer term basis. In some instances, the issue may be more one of supplemental water (beyond what the city system is willing/able to provide) for irrigation of crops.

A diagram of one rainwater catchment system from

On a short term basis, the easiest solution to a temporary water outage is to have a few gallons of bottled water around. Another solution is to use the water from a hot water heater as a back-up supply. Water from the storage tank of a toilet can also be used.

This may be silly, but for a slightly longer term solution, I bought myself a few children's wading pools (of the "hard shell," non-inflatable type). I thought perhaps these could be put out on the patio, and used to collect water. This solution would only work if neighbors left them in place. This approach wouldn't provide a lot of water, but in a rainy part of the country, it might be enough to "get by" for a while.

Children's wading pool of the type I bought.

A better longer term solution would be a rainwater catchment system. If one wants potable water from the rainwater catchment system, there are quite a number of requirements that must be met. For example, the Texas Manual on Rainwater Harvesting gives quite a few details. One of the requirements for such a system is that the roof used for catchment be made of a suitable material. Unfortunately, asphalt shingles that are so popular in much of the US are not on the list of suitable materials.

If a person uses water from the catchment system only for watering plants, he/she has more flexibility in roof types. It is also not necessary to worry about treatment of the water after collection.

The diagram in the initial panel shows one layout of a rainwater catchment system. In years past, underground cisterns were often used for rainwater storage. These are probably more durable for long-term use.

If you live on a farm, you probably will have a local source of water--typically well water or spring water. With these, you don't have to worry about the city system of delivering water going astray for some reason (bankruptcy for example). Your only concern then is that any pump used for this purpose remain operational. In years past, windmills were used as an economic substitute for electricity for pumping water.

Windmill used for pumping water, from

I tried to think about the issue of how a city or small town would guarantee the availability of fresh water for the long term, but it is hard to come up with a universal formula. The biggest issues no doubt arise when there are true water shortages--for example, water is being pumped from a deep aquifer that is depleting, or water from a river is being shared by a number of communities, and there is a drought. There is a possibility some might go without. Other possible causes of interruption include interruption to the electrical supply, or bankruptcy of one of the major players in the system. Civil unrest could also play a role.

Over the long term, a person probably wants to be in a part of the country (or world) where there are adequate fresh water supplies available. Most of us are not in a position to consider moving, but if one is, it seems like fresh water availability would be up near the top of the requirements for the new area.


1. Is the possibility of water interruption too remote to even worry about?

2. What experiences do you have with alternative or supplemental water systems?

3. I offered some thoughts as to the vulnerabilities of city water systems to outages. What vulnerabilities do you see?

4. What experiences do people from outside the US have with water systems (and outages) that US residents might learn from?

Collecting rainwater, and in some cases, even installing a cisten is ILLEGAL in some states and municipalities. You are depriving local water monopolies of their hard-won profits and doing so makes you into a DOMESTIC TERR'IST!

Gail should be very careful what she posts here --she may be getting a visit from "Homeland" Security.

As far as I know it is legal in the part of Florida where I live. We have more than enough water during the rainy season, actually our problem then is flooding. It makes sense to save some of it for the dry season.

For those poor schmucks who live in states where it isn't legal I'd say you need to do some serious protesting and then work on changing your local laws, ASAP!

Let's just say I would be really upset if someone told me I couldn't keep water that falls on my property. How about swimming pools? Do they come around and measure how many inches have fallen and charge you for the additional cubic feet.

Heh, as I'm typing this it just started to rain, it must be a good omen because its actually the beginning of our dry season just about now.

Obligatory reading for all interested in this vital topic:

Here in Minneapolis, MN the city is giving incentives for people to collect rainwater in order to release it more slowly and productively.

The city storm sewers have been updated, but still all of the pavement and cement and roofs cover areas that once would have absorbed rain water. This means that lower areas have had some flooding problems.

The city is also converting some land back to holding ponds with native grasses and trees. These are beautiful and they help manage heavy rains.

I've got a rain barrel -- home-built from a food-grade drum. Also some collection with large and small containers that get emptied out soon after rainfall. This reduces runoff and makes better use of the water within the city.

No doubt that much can and will change, but for now this seems like a good transitional step.

One home with rain barrels might not make much difference but ten or twenty thousand homes or so with rain barrels can really help reduce the load on the storm sewer system for now.

The states in your link, Colorado and Utah, are in the west. Western water law, because the climate is generally arid, has a completely different basis than water law in the east. In the east, the riparian property owner has rights to beneficial use of the water flowing through the property. In the west, the rule is "first in use, first in right."

That means that a downstream user who first put the streamflow to beneficial use has the rights to the water and upstream users may not divert or use it. That's why the cistern is illegal.

Colorado just changed their laws on water harvesting by single-family residential properties. Here's a cite from Wikipedia:

Until 2009 in Colorado, water rights laws restricted rainwater harvesting; a property owner who captured rainwater was deemed to be stealing it from those who have rights to take water from the watershed. The main factor in persuading the Colorado Legislature to change the law was a 2007 study that found that in an average year, 97% of the precipitation that fell in Douglas County, in the southern suburbs of Denver, never reached a stream—it was used by plants or evaporated on the ground. In Utah and Washington State, collecting rainwater from the roof is illegal unless the roof owner also owns water rights on the ground. In New Mexico, rainwater catchment is mandatory for new dwellings in Santa Fe.

Colorado's law didn't change for more than 90% of the state's population. To legally harvest rainwater requires a permit from the same board that permits wells. And the largest 2 of the 6 hurdles to getting a permit are: you must already have a well permit and you must not be connecteed to a municipal water system.

Interpretation by water board:

I've thought about starting a ballot initiative to change it, however getting 76k signatures is out of my capacity (the elected office I ran for last year needed less than 1% of that, and getting what I needed was pretty darn hard), and I don't know enough people willing to do anything other than bellyache about it.

I just received the latest newsletter from my borough manager's office. In it it lists rain water collection from roofs as something we are all encouraged to start doing. I was surprised to read this mainly because here in the northeast, drought and water shortage conditions haven't really been too much of an issue so far.

For my part to date, I keep five - six gallons of bottled water in my frig (or stored) both to maintain thermal efficiency of the unit (I inherited a much larger refrigerator than I actually need) and also to serve as a short-term back up supply in the event of any problems with the borough water supply. I also have a Pur water filter installed on one of my sink faucets (for the same reason) and a backpacking hand pump type water filter which will process around two hundred gallons. I also always keep some chlorox on hand for emergency purification (two drops per gallon will work).

It is something I have thought about, especially because my storm/emergency food supply is based upon water/rehydrating technology; freeze dried, rice, etc..

I've been thinking about water drums, but those get very heavy real fast. A small, full, fifteen gallon water drum is something like 120 lbs. IICR.

Hi Harm,

According to the Wisconsin state plumbing code it [a cistern] is not designated as a "potable water supply". You would have a zero potential for getting an occupancy permit for a home that intended to use a cistern as a source of drinking water (regardless of treatment methods). However, I don't think there is an issue with having a cistern to assist with watering your Bluegrass lawn.

In December 2007, a major flood destroyed the intake for the local water system that serves about 300 families in our rural valley.

The system was inoperative for several weeks and the water was deemed un safe for drinking for several months.

Initially local volunteer fire departments trucked water to local dairies from nearby communities.

A fire truck water tender was parked at the local Grange hall for people to fill personal containers.

Local people with wells also made water available to those who were dependent on the public system.

I think that in addition to the events that Gail listed, a major earth quake would disrupt water service.

In my valley (PNW) we get very little rain between June 15 and October 1. Irrigation is essential for meaningful agriculture. For that reason, I counsel people in my sphere of influence to place a high priority on developing a private system suitable for irrigation and if necessary personal use.

Some of the things that I advise relative to water retention is probably illegal in Washington state but....

1.9 liters of water may be the minimum for survival, but especially if you are doing ANY amount of physical work, I'd plan on 4 liters of just drinking water. This will include what you cook with, but not washing.

Working outside in hot temps, and I'd plan 2 gallons/person/day.

Hello Gail,

From Bart's Energybulletin [EB]:
Conservationists rip water policy, quit state panel

Members of four influential conservation groups abruptly resigned from a state waterway advisory panel yesterday, alleging that a new state policy undercuts environmental protection of rivers so greatly that some could run bone dry..
The two scariest quotes I can think of are:

"Whiskey is for drinking as water is for fighting"
"Water flows uphill to money".

Woe to us all if we don't have fair and equitable water policies for All Species in the Circle of Life as we go postPeak. I have posted much before on this topic so I will improve the silence by not going into a long rant. Newbies can always do an archive search...

Bob Shaw in Phx,Az Are Humans Smarter than Yeast?


You live in Phoenix? Is not Phoenix the worse place in the US to live if you are concerned about water issues...

But then again this would make you more aware of the importance of water resources. Be OK by me if you get into a rant post about water... Otherwise off to the archives... :)

Mexico City has had problems with water:,8599,1890623,00.html

Atlanta has had water supply problems:

The vast majority of people in California (specifically those inhabiting the San Francisco area, Los Angeles, and San Diego)are almost entirely dependent upon water pumped from the Sacramento delta. Any severe energy shortage could result in those vital pumps being interupted. Earthquake(s) could cut the canals that carry the water leading to a temporary interuption. Worse, even a small sea level rise (about a half a meter or so, perhaps much less) would submerge the intakes in seawater and render the water system unusable. Any longer-term interuptions would render most of these areas nearly uninhabitable very quickly as there are few underground sources that could supply much of a reserve. Even if one installed large cisterns, it would only buy a few days to weeks while all the neighbors would be internally displaced almost immediately. Not much of a reason to stay behind at that point. As it is with the current drought, southern California is looking pretty arid with those formerly green lawns gone brown or even to dirt.

I live in the Atlanta area, so I am fairly much aware of the Atlanta water problems. Part of the problem was drought; an equally large part of the problem was too many electrical utilities (from Georgia, Alabama, and Florida) vying for too small an amount of water. I understand that at least one nuclear power plant almost needed to be shut down for lack of water.

Most people around here with vegetable gardens find it necessary to water them at least some of the time. If any significant portion of the population decided to do this, I find it hard to believe that the city system would keep up with the water requests.

As I understand it, the water disputes with other states are still not entirely resolved. Atlanta has been told it does not have legal right to the water from Lake Lanier it is now using for drinking water. See Federal judge rules against Ga. in water litigation. I actually live in an area where the water is from another lake (Lake Alatoona), but the area in general has a problem with water.

Well, it's even worse than that. LA gets a lot of its water from the LA Dept of Water and Power aqueduct from the Owens River Valley. (See the movie Chinatown for a fictional account of the Owens Valley wars). The rest of Southern California and San Diego are supplied by Metropolitan Water District water from the Colorado River. As far as local water is concerned, the runoff from the San Gabriels is diverted to holding ponds where it infiltrates for groundwater withdrawals. I seem to remember reading that Orange County does the same with its sewage effluent.

At any rate, any way you look at it there isn't enough local water for the millions of people in Southern California.

For decades Orange County has been re-charging its aquifer with tertiary treated water that flows down the Santa Ana River from inland communities. Now it is doing so at the lowest end of the Santa Ana River and treating effluent to an even higher level and then pumping up to these same recharge basins. That makes a lot more sense than letting highly treated effluent flow to the ocean where it can mix with saline water only to pump it out and treat it in the same way. The cost of treating the water before it hits the ocean is much less than after it mixes with the ocean water.

We have a water capture and storage problem in Southern California. Over a billion gallons of effluent a day flows into the ocean between Ventura and San Diego. Water law is archaic, riddled with inconsistencies, and rife with political challenges. When we price water appropriately, we will start to see the kinds of reforms that are needed. Until then, we will continue to waste it while simultaneously encouraging a culture of fear of running out. People here are generally shocked to learn that MWD rates have gone up because people have conserved so much water. The infrastructure needs to be maintained no matter how much water is transported.

Finally, thank goodness LA stole water from the Owens Valley. Had they not, this beautiful stretch of geography would be just another LA style burb.

1) Should we worry? Yes, I was in Reserve LA following Katrina, every piece of infrastructure in the town was up and going, problem was the population went up by 125% in 72 hours. All infrastructure was now in overload including water. Imagine a truck bomb on one of the three? pipelines into NYC. How do you get water for say 5 million people? Everything I've read, and my experiences in the third world would lead me to believe that water ties with shelter as an issue of criticality.

2) Experiences. I bought a farm with a spring and springhouse, and I've been careful to maintain it. In fact I have it attached to my
farm water distribution network, which keeps expanding. I'm about to extend the network to the public road, because my system is probably a lot more robust than the town's, and I want to invest for my neighbors. Fascinatingly while my house has a well, my spring house water always tests better than the well. I drink from the system all Summer when i'm in the fields and obviously irrigate with it. I have cedar shingles on my roof(s) and have recently bought barrels to catch the rainwater for plants and as the ultimate passive backup.

3) NYC's is incredibly vulnerable to terrorists, but gravity fed. Philly's requires pumping. LA area's water from the colorado is pumped, every piece of sci fi i've ever read on catastrophe for LA, is "snow drifts" of bones of people trying to escape for lack of water. Millions of people aren't suppose to live in a desert like that. My town (of 42,000) plus is old enough and de-centralized enough that there are just myriads of even shallow wells that provide residential water. Even where eventually they brought in water pipes, some people opted out, and others who opted in didn't remove their wells. Many of the wells are shallow (the Northeast has water to spare most years), so even if you had a "grid down" situation, it would be possible to organize in most areas some form of neighbor centric pumping with gensets until the fuel went away (I use solar). In talking to some of my neighbors, they talk about the streams, and I ask what kind of filters they are going to put in place, and then we talk about the sewer problems there would be, they quickly realize that the streams will be the sewers for too many people.

A last thought, I've wondered if it make sense to endeavor to persuade the civil defense organization in my town to survey for all the shallow wells, and springs in the town, places where it would be energy efficient to create water distribution locally. I've watched
various water distribution programs work in disasters and what comes to mind with those stacks of water bottles is "unscalable" and "unsustainable" and "not very green". As a kid when we tent camped my job was to take the 5 gallon water container (my father still has
it in his basement and uses it, 40 years later) to the water outlet that was shared by 50+ sites, it was heavy! Later as a teen not so much, now at 50 it is heavy again! Today I saw an 8 gallon water tank on wheels for camping and I thought, that might be the device of the future.

When I worked in the Buckhead portion of Atlanta, we would occasionally get notices that "the water isn't safe to drink today." Then stacks of bottled water would appear as a substitute. I would agree, they aren't a very good solution in many ways. It is hard to see them as a solution long term.

I believe the problems in Atlanta were with its pipelines, which are old and in need of repair. A paper I ran across starts out:

The City of Atlanta, like many other cities, is currently facing the challenge of rehabilitation or replacement of much of its existing buried infrastructure.

I expect that at least some cities will find themselves with deteriorating infrastructure, and not enough funds to fix them. So water quality issues are likely to get worse in the future for these cities.

It's worth reading the Pitt Review "Learning the Lessons From the 2007 Floods", about the summer 2007 floods in England:

"The biggest civil emergency in British history

Gloucestershire was one of the regions most affected by the summer floods. The loss of Mythe water treatment works left 350,000 people without mains water supply for up to 17 days. Castle Meads electricity substation was shut down leaving 42,000 people without power in Gloucester for up to 24 hours. Some 10,000 people were left trapped on the M5, and many other commuters were left stranded on the rail network. The impact of the floods rendered thousands of people homeless."

Large quantities of bottled water were trucked in to Gloucester, which came very close to being evacuated.


Some survival subjects I ignore as I think that they are unrealistic or superficial. Water, however, is not one of them.

1. Water availability is more than critical and anyone who does not think about the need and plan for adequate supply is asking for trouble.

2. To understand how serious we take this issue one only has to know that a significant point in the purchase of our property was water availability. A gentleman who lived near by, and recently died at near 100, told us that the spring coming out of the ground under our spring house was the only one left flowing during the great drought in the 1930's for a radius of 3 miles. That the neighbors were at the spring 24/7 filling barrels with water to haul home and save their livestock. This spring fills a pond that holds about 5-6 acre ft of fresh water (approx 2 million gallons and full of fish). Additionally we have a rain catchment system that feeds a 1500 gallon water tank. And last, but not least, our well is relativly shallow for these parts, has a very high flow rate and the water heads almost to the ground level. We also have a handful of gallon bottled water jugs on standby in the pantry. If things go south I expect to have the neighbors come for a visit. Though 3 of them have their own ponds of which one is spring fed and very similar in size to ours.

3. Perhaps a major future factor for city water is that a large percentage of large city water mains are way past their expected life spans and badly need replacing. How are they going to find the resources to pay for that. Seems like they will have severe water problems just from neglect eventually without having any kind of regular disaster befall them. No?

4. When I visited Australia some years ago it seemed like very large numbers of houses in some areas got ALL of their water from catchment systems as there were no wells or municipal lines.


Water isn't an easy issue to deal with--especially with roofs made of materials that are not suitable for collecting water for drinking, and with some laws forbidding rainwater harvesting.

When I visited the Red Desert in Wyoming, I was surprised at how dry and sparsely populated it was. The newspapers reported dropping water tables. I suppose one keeps digging deeper and deeper wells, but at some point that approach won't work, for one reason or another. With little water, it is hard to see how the population is very sustainable, unless there is a good transportation system for food and most everything else..

Got the gutters up this week ...

can collect up to 10,000 gallons

collectable rainwater (gallons) = 0.5 x rainfall (inches) x area (square feet)

I have a 50 kL or 12,000 US gallon household rainwater tank. Gravity feed is normally inadequate for the kitchen and bathroom so you need a pressure triggered electric pump of say 400 watts. If the grid is down it won't work so there won't be any pressure in the garden hose in the event of a fire. Note that grid tied PV also shuts out when the grid is down.

I've rigged up a quick connection to a petrol driven fire pump in the event of a simultaneous blackout and bushfire. Of course you have to be home when it arrives as it won't turn itself on. I'll also experiment with 12v solar pumping of pondwater to an uphill tank.

A recent problem I didn't expect was mild poisoning when I painted the roof with waterproofing compound. An inline charcoal filter can remove flakes from drinking water but not dissolved chemicals. Same goes for resin drops from trees. I don't like open top containers as I think all exposed water surfaces should be covered with fine mesh to prevent access by birds, rats and mosquitoes.

Note that grid tied PV also shuts out when the grid is down.

Disclaimer, I sell commercial, agricultural and residential PV systems both grid tied and grid tied with battery backup.

However I've begun to notice more and more people even in urban settings are asking for systems they can depend on when the grid is down. Just for the record it really seems to bother people when they have say 30 thousand dollars of panels generating electricity on their roof and they they can't use it.

Yes, the extra inverters and batteries cost more but it is sure is nice to have power when your neighbors don't!

We haven't had a big hurricane around here for a few years, I strongly suspect there will be an increase of requests for battery backup systems after the next one, especially if people can't get gasoline or diesel for their generators, which often happens after a big one hits.

Given the current state of the world My personal judgement is that the risk of many large cities and some towns running out of water is unacceptably high.

A hot war that reaches our shores will bring down the grid.
A terrorist with a truck bomb or just a barrel or two of the right(ow wrong, as yiou choose)chemicals could shut down a water system for a long time.
Believers in climate change who are also aware of just how heavily overstressed lots of water systems are will quickly agree that it's not just California and Atlanta and Las Vegas that are in potentially very deep doo-doo.

Drilling new wells in many parts of the country as the local water table falls has been the very best possible small business -the waiting list north of Richmond Virginia was six months and more a couple of years ago.

Our hand dug well that hit bedrock at about sixty feet went dry-after fifty years- a few years back due to a combination of dry weather and lots of new houses in the immediate nieghborhood.

Our new well didn't hit pay dirt until we went over seven hundred feet.

Fortunately we have a spring that is potable and that has never failed uphill from the house-we have bitten the bullet to lay a very long pipe line to it and we now have two sources of potable water-one gravity fed and adequate to keep a couple of acres of garden well irrigated.

A man I know had to move his wife and four kids into a motel for a week due to an ice storm cutting off his electricity-he couldn't buy a generator or hire any body to hook it up to his pump on short notice at the time.He has a generator adequate to run his well pump now.Think about this as an example of a problem as compared to someone in New Orleans during Katrina or LA if the water supply fails for even a day or two-it pays to settle in a good spot if you ever move for any reason.

We have two steel tanks that we use to catch roof runoff that hold over five thousand gallons each-you could get one almost for free(scrap price plus delivery) when they were outlawed for use as underground gasoline storage.Obtaining such a tank cheaply now is probably impossible but there may still be other tanks around for the hauling that would be usable.

We also have a temporary swimming pool that we keep full in the summer that must hold another three thousand gallons.

And we don't even as a rule need this water-but in the event of a serious fire it will be priceless-the nearest fire hydrant is over ten miles away.The local fire dept knows about our water tanks of course.

If someone is interested in establishing a safe and secure supply of water for emergency use one way would be to buy a large concrete septic tank-the come in sizes at least up to two thousand gallons and are built to last pretty much forever and if you just call it a cistern it won't embarrass your kids.

One of our nieghbors has set a bunch of concrete well tiles in a row with the bottom of each one embedded in concrete and a well cap on each one as a reservoir to catch and hold the flow of his spring which flows only a trickle.They are all interconnected and he never runs out of water now as the daily flow of the spring exceeds his daily usage.

I don't use them for water but I have scrounged up lots of fifty five gallon plastic drums that are very sturdy and have screw caps which were originally used for various food products such as syrups and oils.

Such drums -when you find them -are really cheap-I pay anywhere from five to ten dollars each for them.If you can find drums such as this they would make fine emergency water containers once washed thoroughly.

I can take no credit for it but my greatgreat grand parents recognized the possibilites of the lower reaches of the mountians when they moved into this area over a century ago-there is usually very good soil in the creek bottoms and decent soil on the lower hillsides.No tornados.The streams have never run dry.No floods-unless you build in the bottom , which should be where you grow your corn rather than build your house.

You are sheltered from the worst effects of hurricanes even if one gets inland.

There is likely always going to be plenty of firewood as most of the land is too rough to farm or build on.

There is a wide range of micro climate which means that you can often do a lot more in terms of gardening and farming in such an environment than you can in other places even if you have only a few acres of your own.

Such places as a rule aren't very crowded .

Such things are worth thinking about if you are considering a move to a place with high survival potential.

According to the book: The Clean Tech Revolution (page 224),
something that could be useful for providing water in emergency situations
[just for drinking and for medical purposes]
is a technology that obtains water from the moisture of the air.
It doesn't use refrigeration, and it sems that does not require too much
electrical energy.
About US$ 0.30 per US gallon.
One unit of this equipment can get 600 or more gallons per day.
Aqua Sciences.

You know I was fairly negative about these devices, until I realized that I have to run a dehumidifier in my basement from time to time,
and some of these units draw less power than my dehumidifier. So, I'm tempted to buy one, for that purpose, to generate some water, and as an odd backup for the basement "redoubt".

you dont want to drink that water except in a true emergency. It's essentially distilled water, which
will suck minerals right out of your body as it passes through you. If you must drink it, try to mineralize it first
with clean clay or even dirt, let it settle, perhaps boil if you fear bacterial contamination, before drinking.
not perfect but better than drinking the stuff straight out of a condenser or still.

you dont want to drink that water except in a true emergency. It's essentially distilled water,

Water from a dehumidifyer will also have funky mold spores + higher Aluminum levels.

Water from a dehumidifyer will also have funky mold spores + higher Aluminum levels.

And it tastes awful.

It's essentially distilled water, which
will suck minerals right out of your body as it passes through you.

Do you have a cite for this?

My career and education is in Water and Environmental Chemistry - as far as my education and experience goes I understand that he is quite correct in his comment of distilled water being dangerous for long term consumption. Water is also known as the universal solvent - H2O in its pure form is a very strong solvent and 'wants' to have impurities. If its only source of impurities is you, then you will be giving up calcium/magnesium and other minerals quite readily.

here is a quick list of googled references on the topic..

(I didn't go too crazy in qualifying the credibility of each source... but they arent the worst sources)

this one is a little self promoting, but they hit the highlights...


Pubmed contains no published papers on searches for

"distilled water"[title] and leach


"demineralised water"[title] and leach

Looks like hogwash and hearsay to me.

I worked in water treatment in the Jefferson area of New Orleans many years ago.

A lot of municipal water is very low in minerals and I have not heard of this cusing any health problems. The primary minerals in water are calcium and magnesium carbonates,bicarbonates, slufates and chlorides. I would consider less than 25 ppm of Ca + Mg as low. Often lime (calcium oxide, which turns to carbonae and bicarbonate) is added to minimize corrosion in steel pipe. Above 500 ppm total dissolved solids is considered too high, mainly because the Ca and Mg hardness adversely affect soap detergent action in washing. This is a dry region problem. Levels would probably have to be much above 500 ppm to affect health.

Low mineral water is common in areas of granite and shield rocks, like the Eastern US peidmont and parts of New York state and Eastern Canada and in leached sandy soil like the Atlantic and Gulf coatal plain.

Anyone worried about mineral deficiency can take calcium and magnesium supplements.

Distilled water is corrosive to steel and some mild stainless steel alloys. A corrosivity index exists to help determine corrosiveness based on water chemistry.

Water from a dehumidifier should be treated with an activated carbon filter to remove dissolved metals, taste and odor.

The American Water Works Association has numerous publications available, but fees are charged for many.

In years past, windmills were used as an economic substitute for electricity for pumping water.

In USA, the first patent of a windmill well pump was granted in 1850s. Electricity didn't arrive at the well head until FDR era rural electrification. Before 1930s there were windmills and hand operated lift pumps only. There was very little use of draft animals to provide pumping power in US, I believe. FDR killed the windmill industry. Rural electrification was social policy, not economics. It sure changed the face of the American West!

Arron Newton sent me a link he did to a post he did on water and water catchment systems. This is an excerpt:

Water for irrigation is available from four sources: ground water, municipal water, grey water and rain water.

Ground water is available from springs or by drilling a well. Many parts of the country can support moderate amounts of water being drawn from underground and recharged naturally.

Some parts of the country however are already pumping water out of the ground a rate much faster than can be naturally recharged. These regions are endangering their futures. It’s difficult to gauge how much ground water is left because it’s out of sight. It is also possible that ground water can be contaminated by natural occurring high concentrates of compounds that are poisonous to humans. Have your ground water tested to be sure it’s safe. It’s also worth mentioning that in many parts of the country, drilling a well can be expensive. Contact a local well drill for more information.

Well just to kick in an anecdote from my situation, suburbs on the island of Oahu, it'd be a bad place to be if the container ships stop coming, and the electricity comes from tanked-in oil. It's not my choice of a place to be long-term, but family obligations have us here now.

That being the case, we've made a few changes with water security in mind. We converted the old swimming pool into a pond, which is fed by flow off the asphalt-roll roofing and can be used to drip-water our tree crops which are all downhill from it (if there's a drought, that is). Several years ago I replaced half the roof area with catchment-grade metal roofing which could be made into a potable water system fairly quickly; and there's significant rainfall here even though it's not as regular as it was 20 years ago; currently having showers related to the hurricane just south of here.

And I've also picked up a number of the 55-gallon plastic food drums FarmerMac talked about - a great bargain even though I had to pay $15 each for them. They're good for all kinds of things; you could probably even lash them together and go interisland. I have about 20 of them in the back yard ready to be used for anything I decide to use them for. Several are being used for food storage and filtered water storage, immediately drinkable in case of earthquake etc. 100 gallons of ready-to-drink water in a couple barrels in the side yard could come in handy in some circumstances.

We had planned to move to the big isle and set up a large catchment system - in upper puna the rainfall is impressive - but it looks like we may not. But of the weird things that may happen here, we won't freeze or die of thirst.

The first thing I developed on our small spread was the water system (which will show you where my head is at). I needed water for my RV while I built our house. Off grid, I turned to solar. I used two 55 gal plastic drums, One below the spring, one on the ridge above the RV, connected by a run of plastic pipe. Added a check valve, solar pump with float switch, and a tap off of the main line and, presto! a working water system. The spring fills the bottom tank, the solar pumps it to the top tank, gravity does the rest. The 55 gal drums are now 1600 gal plastic water cysterns (bought both for $700 used from a nearby municipal water system, used to mix chlorine solution dilute). These large plastic tanks are designed to be buried. Just make sure they are full while you bury them. Plastic septic tanks work too. A residential system using a 200 gal tank ( and a simple surflo rv pump can be built. Add a 70 watt pv panel/controller, rv battery and you have a small but reliable pressure system that will run a lot of stuff. The rule is Capture and Store. My original sytem has provided up to 600 gal per day at 42 psi for 15 years, even through the recent SE US draught, uninterupted except when I took it down for cleaning. Even then we had 1600 gal to draw on in the tank on the ridge. Poor little grid people, for they know not what they do...........

Related to this issue is the vital SODIS (SOlar DISinfection) concept that can be used to turn dodgy water into potable water with zero energy.

I've heard about this method, the water is apparently disinfected by UV light.

There may be a couple of issues to consider though:

1) Plastic bottles may leach chemicals into the water - especially when the plastic degrades under high temperatures. I think that's why many water bottles say 'keep out of direct sunlight'. I think some plastics are more risky than others in terms of contaminants, but it's a complicated issue. If it were a matter of life or death, it would obviously be a less important consideration.

2) During the autumn/winter/spring period (depending on your latitude - I'm in the UK), there may be insufficient UV radiation to perform the disinfection. This is why despite the sun looking bright, it's hard to get a sun tan or create much vitamin D in winter.

I've started collecting clear glass bottles for this purpose anyway, but haven't actually tried it yet. We have a aluminium greenhouse which we use for collecting water for plants, but intend to replace the water butts with potable water storage containers which, again, are made of different plastic - that apparently leach less.

Is it possible using a 1000x microscope, to check for the existence of living/dead bacteria in water? I've no idea how practical that is.

I think you'd be better off either purchasing or constructing a solar still to disinfect your water.
I built one a few years ago as an experiment and was able to make pure sterile fresh water out of ocean water with it.

I think you'd be better off either purchasing or constructing a solar still to disinfect your water.

Unnecessarily expensive and slow. Not worth it unless water has chemical contaminants.

Andy I think it is heat treating that is being used to kill pathogens similar to the thermalphylic aerobic bacterial process in humanure composting. If you maintian a high enough temperature for a sufficent length of time patogens are killed (both virus' and bacteria). Human pathogens and parasitic critters and cysts are tuned to do best at normal human body temperature and can survive well at lower temps. However sustained higher temps kill them and the higher the temp the shorter the time required. "Boil your water for five minutes" is the emergency mantra always used here in Canada. 50C for six hours seems to be quite effective.

One thing the Wikipedia article above mentions is that polycarbonate should not be used, because they block all UVA and UVB rays.

Obviously, if there are high levels of undesired minerals (think arsenic), solar disinfection will do nothing about the problem.

plastic bottles will definitely be undesirable here because of the great smorgasbord of chemicals
that leach out from the plastic into the water.
however, most glass bottles will block most of the UV from reaching the water. that uv will just heat up
the glass a bit.

you could probably, if you had sufficient solar radiation, use the sun to heat the water to the ~150F or so needed to
kill any harmful microbes. I doubt you'd get that in a place like the UK outside of a clear summer day.

or, heres a thought.. you could put something with sufficient sugar into that water, put it in the sun to warm it up
a bit, and then let some of those same microbes do some useful work for you. they kill themselves off when their job is done. resulting product isnt mere water after that, but it could be no less enjoyable :)

plastic bottles will definitely be undesirable here because of the great smorgasbord of chemicals
that leach out from the plastic into the water.

The SODIS Reference Centre/Sandec has also had to respond to “allegations circulating in a number of print media in developing countries on the carcinogenic risk of (re-)using PET bottles”. These “unfounded media reports” are drawn from research that show that antimony and phthalic acid and phthalate esters can leach from PET bottles. Sandec conducts its own study, together with Empa (Swiss Federal Laboratories for Materials Testing and Research) on “the migration of organic compounds – with special focus on plasticisers – into the water contained in PET bottles bottles under typical SODIS conditions”. “According to the results of this study, the risk of negative health effects caused by reused PET bottles for SODIS treatment is negligible”. SANDEC plans to repeat the study in India “to confirm the harmless nature of the technology in a country where media reports on the dangers of PET bottles are particularly widespread”.

Source: Samuel Luzi, Reuse of PET Bottles for SODIS – Blessing or Curse?, Sandec News, no. 10, July 2009

Plastic bottles may leach chemicals into the water

The official SODIS website has numerous studies that address your issues.

There is no need to even go this far (technologically) with treatment for water. A P.Eeng colleague in the Water use profession reminded me of an old technology that he is using to teach people in Sudan to treat their own water (90% of their wells are contaminated with E.coli and related pathogens) he uses this process find to improve the health of the local residents. He set out criteria that the process must be:

a) simple enough to teach the villagers to a degree that they can pass this knowledge on to others
b) be able to be made onsite by each village
c) functional - to create disinfected drinking water
d) be cheap enough to create and run that the local economies can sustain it.

the result of this criteria was a BIOSAND filter unit - can be made essentially out of a box (peferably inert material) and different gradients of sand.

For anyone who would like further information on how the biosand works -the biologically active portion of the biosand filter is called the schmutzdecke - either I can go into more detail, or google the info...


also look here for more info:

google biosand filter for more info...

*disclosure - I have worked with Enviro-Stewards on projects, but have no personal stake in their company. This comment is not intended to be either an endorsement of or comment on Enviro-stewards as an company or engineering firm, and is intended as information only.

This is one of my favorite topics.

I note that water we collect and treat ourselves may taste very different from the water coming from conventional treatment plants.

Boiling water in an open pan over an open fire will definitely give it unique flavor, in my limited experience.

If one is trying to survive, many things like flavor and worries about plastic containers leaching chemicals into the water will be put on the back burner so to speak.

In the past we've used a big kids pool under the deck - but this has been problematic from the point of misquitoes as well as racoons using it. Fish didn't live long in it.

We also have the cute little 40 gallon water barrels - but they're overflowing within a few minutes of any rain and don't store anywhere near enough water.

We picked up a 500 gallon tank this past spring and we have not needed it at all for our garden due to the rainfall.
We were rather shocked in that the it's translucent white walls were very quickly sporting alge growth.

Drinkable??? It doesn't smell nice!

I'd opt for an underground cistern as it used to be done.
It was only about 10 years ago that a family member was using a cistern for their drinking water.

People in the area have tried to do rainwater collection for their home use (toilets) and were flatly rejected by the government.
When you're connected to the city water / sewage they meter your water use and ASSUME that your sewage is a certain fraction of water use (for billing). If a home suddenly starts putting extra material down the sewer then the billing assumptions go to pot.

This makes me lean towards getting some land outside of the city.

The family considering this was also told that it was potentially unsafe to use cistern water to water the grass. You see some officals are paranoid enough to believe that if (when?) something starts growing in that cistern - well it will not be safe for kids to thru the water when it's coming out of the sprinkler (anything gets put into the air ...).

my entire childhood i only drank tank water at home and all the family and friends alike out on farms. never did we encounter algae. no were any of the tanks translucent. the light is your problem.

in australia here, the government wouldnt give you the rebate on your water tank purchase unless you had it plumb'd to your house internally.

also i dont think its the extra water your putting down your sewer thats the billing issue. is the lack of your water meter ticking over that they dont like.

different note, is it serious that glass blocks UV? this is saying you wont get sunburnt behind my windshield ... cause i certainly seem to get a tan?

If you are wanting to homebrew your own water treatment go grab a salt-water fish tank part supplier catalogue. Look at the parts they use and why.

They have Ozone generators and glass UV light sterilizers. You can make a nice small rig if you try.

The 'homemade' rig would be a sand filter, through a charcoal filter, then bubble air that has went through a spark gap into the filtered water. That spark gap can be made from automobile spark plug coils (thus 12VDC system) Be aware - the moisture in the air when you create the spark gap will end up creating acids in your water you bubble the air through. And the spark-gapped air will attack many kinds of material.

Here is a good link for additional information:

Just yesterday I had a rep from Bushman visit my home (Huntington Beach, CA) to discuss a water bladder that they will be importing from Australia. This kind of storage system opens up opportunities for water storage where height is limited (like crawl spaces and under decks) and codes/CCR's may not allow large above-ground tanks.

I'd like to point out the most excellent talk given at ASPO by Michael Webber on "Thirst for Power - the Global Nexus of Energy and Water". Slides are here:

Wow! What a talk it was. I strongly encourage all with interest in water & energy to read it. A couple of quotes from his talk:

"Civilization can be argued to have occurred in order to gather the necessary number of people together for building water storage projects."


"The timing of water crisis correlate to Chinese and Roman political upheavals and the ends of political eras."


"In the west we have a saying, water flows uphill to a**holes."


"We're switching from foreign oil to domestic water use. We should be measuring transportation efficiency in gallons of water per mile."

He made a good argument that as we replace easy to use foreign light crude with domestic gas, coal and nuclear energy we are essentially pillaging our rapidly depleting water resources. So that plug-in hybrid that so many jokingly refer to as "coal-cars" maybe really should measure their efficiency in gallons-H2O/mile. There's a lot to think about here. And for those of you who get the ASPO DVD's of presentations, you will have the advantage of possibly slowing down Dr. Webber's talk. I was laughing so hard during it because he literally talks at the speed of an auctioneer! I pity his students trying to take notes in class!

I admit I am biased and think Michael's talk was one of the best at the conference. For those in the Austin area, I wanted to let you know that he teaches a 3 day energy crash course geared toward policy folks. I think his next one will be in January. Very reasonably priced and high quality information. Get your local electeds and their staff to attend.

Hi Debbie! You did a wonderful job moderating that session. Thanks!!!

The slides from Michael Webber's presentation are easy to understand. I encourage readers to look at them.

when one looks at the cost of large tanks to store enough water , one might consider a well instead.

With a human/solar pump

there are other units and examples

You can still buy hand operated pumps that work fine in wells that aren't real deep-about sixy or seventy feet is as deep as I've seen one used but they probably can be used in much deeper wells.

Something else I've heard about but never seen personally is a hand operated vacuum still that will boil sea water at ambient temperatures and condense it for use as drinking water.They are apparently intended for use on lifeboats.

It might be a good thing to have one if you may need to drink chemically contaminated water some day.My chemistry has mostly rusted away but distillation is one of the most effective ways of cleaning up water-most common chemical contaminants are left behind iirc.

Hi Gail,

Nice to be in the room with you at BPE Conference last Friday, and I'm sorry I didn't get a chance to introduce myself directly.

The capture strategy should reflect the use, and each use should be passed onto the next best use. For example drinking water --> gray water --> toilet flushing, or, Roof capture --> wetland --> aquaculture / fish pond --> irrigation.

Permaculture has a great deal to say about water, roof capture, gray water systems, biological treatment systems, storage and management. Dryland, humid temperate and tropical systems will be very different. Dryland storage, where evaporation exceeds precipitation, needs to be covered, whereas open storage in ponds is suitable in cool humid areas like Western New York, where I live. Mollison suggests 15% of the landscape in ponds, 15% in wetlands.

We should also look at trees, plants, animals and soils especially as water stores. Trees have additional interactions with precipitation patterns in that forests produce rain down wind. I'm guessing part of the South's recent drought problems can be traced to deforestation and timber interests, but I haven't pursued this line of thought researched this thoroughly.

Swales are very powerful and low tech way of storing water in soil, even in the most arid situations. See Greening the Desert for how this works.

Shrimppop, thanks for your link to Greening the Desert. Fascinating and well worth pursuing...

This is a lot more demanding in an acutal installation than any article or t.v. program will indicate. The little rain barrel types are easy stuff but installing a large cistern is a different situation entirely.

There is absolutely no substitute for working knowledge of these installations. Cisterns have been continuously installed in our midwestern county since the mid 1800's so the local knowledge is exceptionally strong. When we started having some problems immedately after installation of our 3,000g in-ground system last year that resource came into play as the installer and material supplier both knew exactly how to handle them. They also knew the problems we experienced were normal and explained the routine maintenance to keep the system functioning [yes, they do require regular inspection and maintenance]. All of the components of our system were also manufactured locally with local resources which is a tremendous advantage when combined with the local knowledge base.

If you don't have local direct and extensive knowledge, keep it simple with some sort of low capacity [a few hundred gallons] surface system and don't plan on using it as potable water. Anything else will set you up for expensive and energy intensive filtration and purification systems not to mention the problems with maintaining the system.

It is worth doing, just take your time and do your research.

Here in Australia, due to the continent-wide drought over the last few years, local Councils and State Governments have been heavily promoting the installation of 'household scale' water tanks, to the point where in South-East Queensland, at least, the installation of a 5000L tank is mandatory for a new home.

Historically, we've installed corrugated iron tanks, but the trend recently is to heavy-duty plastic tanks. The old 'standard' round tank is still the most popular, but 'slimline' and bladder tanks have become very popular, due to the modern practice by home builders of building McMansions practically up to every boundry fence, and leaving barely any room for the dog to play in, let alone install water tanks.

My parents house has 14,000L of drinkable water storage installed, with another 4,000L of non-potable storage. My Girlfriends parents house has about 10,000L of storage that is not presently hooked up. The property my gf shares with her brother has about 20,000L of potable storage hooked up, plus a small dam (which, due to being dug into shale, leaks into the ground. A good thing in the end, I suppose). The (non-mcmansion) house I am planning on constructing will have a mammoth 100,000L of underground potable storage, which is enough to get a family of four through six months of use, assuming each uses 140L/day - the recent target of the Queensland Government until some huge storms refilled our supply dams to respectable levels). Assuming historical rainfall levels (a dangerous activity, these days, it seems), this gives me a huge buffer to work with.

Even ignoring any doomerish predictions, having at least a short-term backup supply is an intelligent thing to to, imo. There's any number of reasons why even 1,000L of potable water could become a life-saver (the same goes for other emergency supplies, like batteries, canned food, alternative electricity sources, etc etc).

Good post..

Though 12,000g [I believe that translates to about 45,400L] systems are in use and 6,000g is not unusual in our area they are usually for ag. purposes. With the unusually wet weather in the midwestern U.S. the re-charge rate is so rapid in our area that our 3,000g [11,356L] system has been running an overflow.

We utilize cast concrete cisterns produced by our local pre-mix plant which are expandable by the addition of additional 1,500g [5,678L] sections. Water is lifted from it with a submersable shallow well pump. Typically every 4 to 5 years the interior is cleaned and inspected for cracks, which rarely happen after the inital 6 months of installation, if found they are repaired with hydralic concrete.

Corrugated pipe wouldn't make the health code here and the heavy duty plastic has its own set of problems related to all plastic products. The biggest problem with the plastic jobs it making sure they are properly anchored. If the concrete jobs settle the plastic things will rise if not properly anchored in areas where ground water is an issue. I think the plastic ones may best installed on the surface if ground water is questionable. We are on the top of a ridge and even here an open excavation will collect water at some times in the year.

The old installations still in service are not filtered in any manner. Our code calls for a sand filter which in our case is 800g. [3,028L] It is never backflushed but every couple years it is inspected and if necessary just the top couple inches of sand is removed and replaced.

You did hit a critical point in mentioning the need to conserve

Last night PBS had a program about Yellow Fever, which created serious epidemics in the US until as late as 1905.

Since it is carried by mosquitoes, anyone collecting rainwater should remember to put a mosquito screen over whatever they are using to store rainwater, to prevent mosquitoes laying eggs, and a resurgence of dread diseases. Climate Change is moving those diseases north, and we should be prepared to deal with Malaria, West Nile Virus and others.

Edit : Malaria was found in the southern US as late as 1950 (eradicated by wholesale spraying of DDT)

see below

One cause of water failure (as well as oil) that hasn't been mentioned: solar flares can cause electromagnetic pulse in power lines, taking out the grid in large parts of the US for a couple of years. Most water supplies have electric pumping.

January 21, 2009: Did you know a solar flare can make your toilet stop working?

This solar storm has occurred 3 times in the last 150 years, so about a 2% chance per year. The last one fried a huge power transformer in Quebec and took down most of Quebec.

It is good to have some water storage containers around. If power goes out, water in cities will still work for a few hours until the water towers run dry, so you can fill containers and bathtub. I use the Army 5 gallon (20 liter) plastic jugs, 40 lbs each (Brigade Quartermasters, but Google it to find a cheaper place to buy them).

Storing water is even more important than a good food stash.
Here in the high desert it may not be practical for rainwater cisterns because of our extremely low rainfall, but that does not mean we shouldn't have some amount put away.
We're got 3 - 50 gallon food drums filled with water in the garage.That's hopefully enough for our family of 3 to get by for a couple of months. Also I've built a 140 gallon horse-trough hot tub which will hold another month or so supply.
And I hope to put in a small pond this year near the garden.
Of course having water and having clean water are two different things.
Have to read up on sand filters to get the ick out of the water, and other methods for cleaning it.
A couple of ideas on sterilizing water appeal to me.
My winebox solar rice cooker (double jar cooking with a reflector) will do 20 oz of rice in just over an hour, and the temp has been measured at near boiling during that time. That should work for water disinfecting I hope, and with a good full day of sunlight, should be able to put out (at 6 charges per day and 20 oz each, about 120 ounces of clean water.) That is, of course only if the sun is shining. The cost was only a few cents for black spray paint and the nesting jars were free.
Boiling IMO seems the best way to purify(disinfect).
Another method which seems to work is distillation. I've used a plastic mortar mixing tub to sucessfully distill a cup or so a day. Just tilt the tub slightly, fill partway with water, cover with an old sheet of glass, and collect the water at the lowest point into a jar. tastes kind of flat, but supposedly pouring it into jars will add oxygen and make it taste better. Distillation might be a good way to go to re-use grey water, especially if added foil reflectors were used, and even double distilled?
My old solar box ovens should be able to purify, oh, say 5 gallons each on a sunny day, as they'll get up to 300+ degrees.
So the considerations I see are to get a good stash, and make it drinkable.
I do use glass jars for my water, and really don't like the idea of plastic, because of potential leach-off chemicals.

Sure wish more people around here were doing this, because if the power goes down, and the water quits coming out of our taps, it's going to get really ugly. Really fast.

Here in the high desert it may not be practical for rainwater cisterns because of our extremely low rainfall, but that does not mean we shouldn't have some amount put away. ...

... So the considerations I see are to get a good stash, and make it drinkable.
I do use glass jars for my water, and really don't like the idea of plastic, because of potential leach-off chemicals. Sure wish more people around here were doing this, because if the power goes down, and the water quits coming out of our taps, it's going to get really ugly.

I'm confused by this statement.

Cisterns are a 'stash.' What's more, they replenish themselves automatically. How fast they replenish depends on surface area of the roof and inches of rainfall. But even a moderately small roof in a very dry region will still produce hundreds of gallons per year.

100 sq ft of roof * 4" rain = 33 cubic ft = 250 gallons

Gail, I think long term water supplies are an important concern. But just like domestic energy use, water supply is much easier to solve if we deal with the various types of water use differently. For example, water for gardening use does not need the same level of purity as for drinking and cooking. (Same for water used to flush toilets, but I am not sure that in a water emergency flush toilets should continue to be used.) To that end, the more we can gather and store water which will be used for agricultural use separately, the easier it will be to handle the drinking and cooking water needs.

Probably the easiest, cheapest and most direct way to store water for plants in our yards, is to use the soil itself as the "storage tank." There are a variety of techniques for modifying your landscape, so that rain water off your roof and paved areas is allowed to percolate in your soil for storage. Too much info to cover in a reply here, but truly dramatic results are possible. I'd recommend people take a look at Brad Lancaster's books (pictured in another reply to this thread). He has been able to take a dried out lot in Arizona and grow an amazing amount of plants and food, entirely from captured and stored water which would otherwise have been runoff.

Water storage needs to be approached at several levels. Collecting and storing water for drinking and cooking needs, for washing needs, and for agricultural needs. Since the agricultural needs are usually the biggest user of water (especially if one is trying to raise food), any storage plans which eliminate the need for cisterns, pumps and plumbing for this water will make for great savings.

Atlanta averages 4 feet of rainfall per year which is a lot.
Collected over a 2000 sf roof that's 60000 gallons of water per year. You could mandate rainwater cisterns for gardens and lawns.

If you retrofit houses with high efficiency water saver type fixtures like they did in California an average family would cut use by ~50% from 120 gallons per day to 60 gallons per day per family.

But that's probably too much socialism for Georgians.

After having lived on catchment water for the last 23 years (mountain stream water for the 11 years before that), I can offer a few comments based on experience:

The best roofing material is painted metal, glazed tile or concrete tile. Untreated wood shingles would be OK, but will impart some flavor when new. Paints are essentially plastic, so a painted surface in contact with the rainwater is plastic. Bare or anodized aluminum would be OK, since the oxide surface is very inert, but copper, tern, and galvanized roofs will shed metals and asphalt roofs will shed oils.

Keep all trees and vegetation at least three feet away from the roof. This will help keep rodents off the roof. For those that have anything connecting to their roof from other structures, including power, cable and telephone lines, special care will need to be taken to keep animals from reaching the roof via those connections. I have never filtered or sterilized the water off my roof and do not worry about birds or bird droppings, since most water born illnesses from catchment systems would be from mammal vectors. Trees anywhere near the roof, even many yards away, will shed leaves or needles into the gutters, which is not a health issue, but will mean a lot more gutter maintenance.

My gutters are roll formed painted aluminum, and downspouts and collection piping are PVC. If you install a bypass or dump pipe to divert water away from the pipe to the storage tank, be sure to screen the outlet. I have had a rat get on my roof by entering from the bypass discharge and climbing up the INSIDE of a downspout to the roof.

I highly recommend a reinforced polyethylene liner for the storage tank, even for those who can afford a concrete or welded steel tank. I worry a little about vinyl chlorides coming off a PVC liner. My current 40,000 gallon tank is corrugated galvanized steel with a poly liner. My previous tank was an in-ground 25,000 gallon "pond", lined with polyethylene film and covered with a rodent-proof roof system. Since it was in a horse pasture, the tank needed to be protected by a good fence.

An opaque roof over your storage tank will keep your water clear and algae free, so it will taste better, but probably not make much of a health difference. I use corrugated steel roofing. Many people here in Hawaii use shade cloth up to 90% opacity, but they still get a lot of algae.

I use gravity to convey catchment water from my roof to the storage tank and a small, 1.5 gpm, DC pump to pump the water from the main storage tank up a hill to a 2,000 gallon supply tank. I usually pump once a week for several hours. The pump I use is normally used to pump water into a captive air pressure tank, which is what most of my neighbors do.

Once the right equipment is in place, living on catchment water is easy. The water tastes great and one always has the comfort of knowing the exact status of the household water supply.

A shallow review of Colorado's water future:
35% increase in population and a 15% decrease (average of models) in precipitation.