Big Picture Water and Irrigation Considerations, by Terry Wyoming

As background, I am a water rights attorney with multiple engineer degrees who formerly worked as a drinking water treatment plant operator.  Given that water is a preppers most precious resource, there is no lack of advice for preppers about water treatment, storage, and procurement.  Despite this, very few people truly understand where their water comes from and the factors that influence the availability of water in rivers, lakes, and streams. However, this information is crucial for planning water supply and retreat locations. Below are some important considerations regarding water sources and delivery. Some of this is information specific to the western U.S., but the rest is universal.


The 100th Meridian, which runs north and south through North and South Dakota, Nebraska, Kansas, Oklahoma, and Texas, has long been an important reference for western settlers.  This line is considered a dividing line between lands requiring irrigation for the production of crops to the west and lands to the east enjoying sufficient precipitation to support a crop without irrigation.  Much of the United States and the American Redoubt lies to the west of this line.

Because of the arid nature of these lands and the need for water, early settlers (primarily miners) established a unique system for allocating this scare resource.  In the west, this is known as the Prior Appropriations System and is based on the mantra “first in time, first in right.”   All states west of the 100th Meridian utilize some form of the Prior Appropriations System.  Under this system, water is allocated based on the timing of its first use.  Thus, the first person to divert from a stream has a superior right to use the water over all people who come later.  The earliest users are referred to as “senior appropriators”.  Senior appropriators are entitled to receive their water before those junior to them.  In the event of a drought, senior appropriators can “call” for water and require upstream junior appropriators to cease diversions until the senior’s water right is fulfilled.  As an example, a call during a severe drought may require anyone with water rights obtained after 1895 to cease diversions, but a call during a wetter year may only require rights acquired after 1970 to stop diverting.

The right to use the water is documented by a water right decree, which can be sold separate and apart from land.  Water right decrees limit the amount, place, timing, and purpose for which water may be used.  Water right decrees also assign a priority date, which dictates seniority.  While this description is a gross simplification of how it works, the basics are all that is important for purposes of this article. This description is based on my experience in Colorado, and there are variations among the states.

As the water demands have increased, water users have developed complex methods to ensure that their water right is available even during droughts.  These methods include augmentation plans where senior water is released from an upstream source to compensate for a more junior diversion at another location; or exchanges where junior water is diverted at an upstream location, but senior water is provided somewhere downstream to satisfy a downstream senior call or recharge ponds where surface water is stored in ponds for the sole purpose of recharging the ground water to compensate for delayed groundwater depletions that result from well pumping; or transbasin diversions where water is transferred over mountains from one water basin to another.

As you can imagine, this system can get complicated quickly.  States maintain massive databases documenting water rights and seniority. In Colorado, the Division of Water Resources and the State Engineer are charged with administering the prior appropriations system.

As a result of these ever-evolving water delivery schemes, most rivers and streams west of the 100th meridian have been transformed into nothing more than a complex pipe network with little resemblance to its natural condition.  The same is true in the eastern U.S. as a result of networks of dams.  While most people understand that dams dramatically alter natural flow patterns, the impact of dams often pales in comparison to the effect of the prior appropriation system.  It is absolutely crucial for all preppers to be aware of the system of water use within their state and to have a basic understanding of how it influences the flow of rivers and the levels of lakes and reservoirs.   How a river or stream near your retreat looks today may have little resemblance to what it will look during TEOWAWKI when natural flow conditions are restored.  Below I highlight some of these issues and describe what you can do to prepare for them and evaluate the reliability of your water supply.


Dams are prevalent throughout the United States for flood prevention, navigation, water storage, and even recreation.  While dams are arguably useful for these purposes now, their existence can create significant hazards and uncertainty during a prolonged TEOTWAWKI event.

Most larger dams have outlet works that can be opened and closed to regulate the height of water stored behind them.  Some also have a spillway, which is basically an emergency release mechanism to prevent water from overtopping a dam when the water coming into the reservoir is greater than the water that can be released by the normal outlet works.  The purpose of a spillway is to protect the dam from damage.

If and when SHTF, it is difficult to predict how all of these dams will be left (i.e. outlets opened or closed).  If outlets are left open most reservoirs will eventually drain completely.  If outlets are left closed, reservoirs will likely fill and cause spillway releases or will overtop dams.  The status of the outlet valves will dictate the water level in the reservoir and will influence the flow in the downstream body of water.  The effect will vary dramatically depending on the size of the dam. 

The status of outlets will also dictate downstream safety. Dams without spillways whose outlets are left closed will create a significant downstream flood danger.  As a reservoir fills, the water exerts increasing pressure on the dam. The increase pressure can result in earthern dams becoming saturated which weakens the structure significantly.  Moreover, if a dam is overtopped, the flows can scour the dam which weakens it.  Even dams with spillways may be weakened from repeated spill events.  The breach of a dam can cause massive flooding and damage as it results in a huge release of water.  Here is a link to a report of a large dam failure outside of Estes Park, Colorado:  The bottom line is that you do not want to be downstream when a dam fails, and the likelihood of such a failure will increase during a prolonged TEOTWAWKI event, as maintenance of these structures ceases and they are left in dangerous conditions.

Moreover, spillway releases are nothing more than partially-controlled flooding and can cause serious damage.  Here is a link to a photograph showing a spillway in operation.  The spillway is to the left and the outlet works are on the right.  Thus, even where dams are behaving as designed, they can cause serious downstream carnage.

Being aware of dams near your home or retreat is important for both safety and for water supply purposes.  If the level of the lakes or streams that you plan to rely on when SHTF are influenced by dams, you need to be aware of this to adequately assess water availability and to plan for any changes that may occur when the operation and maintenance of these structures abruptly ends.

Transmountain Diversions

Despite the fact that water is the most important resource for maintaining human life, humans continually chose to settle in locations with inadequate water supplies. As a result, massive water projects have become necessary to carry water from places of abundance to places of need.  These projects can include hundreds of miles of pipelines and require massive pump stations that cannot operate without electricity.  As a result, many population centers receive an artificially-augmented water supply that would not otherwise be available. The instant these projects cease to operate, many places (like Denver, Colorado Springs, Fort Collins, Los Angeles, San Francisco, San Diego, and many other large metropolitan areas) will experience an immediate water shortage.

These projects not only impact the amount of water that comes out of your faucet, but also impact the flows of water in rivers and streams.  This occurs in two ways.

First, many of these projects do not use pipelines for their full distance.  Rather they discharge into reservoirs, which in turn make releases to rivers thereby transporting the water to its place of use.  In Colorado, there are approximately 24 transmountain diversions which take water from the west side of the continental divide and convey it to the front range population centers.  Without this water, the growth of Colorado’s front range would be severely limited.  Denver, in particular, relies on massive transmountain diversions to meet the needs of its inhabitants.  On average more than 500,000 acre feet of water is diverted across the continental divide in Colorado each year. This is equivalent to approximately 163 billion gallons of water.

The situation in California is far worse.  In fact, just three projects in California– the Central Valley Project, California State Water Project, and the Colorado River Aqueduct– transport approximately 9 million acre feet of water per year. This is nearly 3 trillion gallons of water that would otherwise exist in a completely different place.  Smaller scale transbasin pipelines also exist in Wyoming, Arizona, and Utah, and others are being planned.

Even where these projects are not being directly diverted into rivers and streams, they eventually end up there.  The wastewater that you create when you wash the dishes or flush the toilet goes to a treatment plant where it is “cleaned up” and then released back into the environment.  Unless this water is discharged into the ocean it goes to a river and other people use this water for drinking, washing, growing crops, et cetera.

As a result of all this water, the natural flow of many rivers is being artificially augmented.  This is incredibly important to understand because, when SHTF and these projects stop operating, the status quo of many rivers will change dramatically.  What was formerly a flourishing river year-round near your retreat or home today may be a dry creek bed eight months out of the year once SHTF.  As a result, it is imperative that preppers do sufficient diligence before committing themselves and their families to a particular water source.  Having all the beans, bullets, and bandages in the world does you no good if the water source you planned on using ceases to exist when SHTF.  I urge you all to do as much research as you can tolerate to ensure that you do not find yourself in this situation.  Whether you’re selecting a retreat location or just a home where you plan to bug in, you absolutely must vet your water supply.

Effect Other Water Users

Obviously, water availability and quality are important considerations when selecting a retreat location, or simply selecting your main residence (if you are planning to shelter in place).  People often look for properties with springs, wells, or nearby surface water.  As mentioned above, the fact these water sources appear viable in present day is no guarantee that they will be around to serve your needs come TEOTWAWKI.

First, you must consider water quantity.  The prior appropriation system, at least in Colorado, is carefully administered by the State to ensure that those with senior water rights receive their water first regardless of their physical location on a stream reach.  Once the ball drops, it is highly unlikely that there will be people running around administering water rights and running the highly complicated computer models that keep the system running smoothly.  Instead, anyone capable of diverting water is going to do so, regardless of the priority system.  As a result, downstream users may discover that there is no water left for them to divert, regardless of any water rights they may have.  This is particularly true if your water supply is dependant on transbasin diversions. As a result, it is important to be cognizant of your upstream neighbors and their ability to divert water. If all the water is diverted before it gets to you, then your expensive riverfront property is essentially worthless.

Many wells, mostly alluvial wells, are also influenced by nearby surface waters. Thus, you could find yourself in a situation where the creek through your property is dry because of upstream diverters and has in turn caused the level of your well to drop so significantly that it is no longer viable. You don’t want to be that guy. Know what influences the availability of water in your wells, springs, and surface water before your rely on them as a back up water supply. It is also important to have a general idea of how much water your upstream neighbors are capable of diverting.

The second consideration is water quality. As Coloradoans learned in the recent flooding, once wastewater plants stop operating, the river and stream become polluted very quickly.   Wastewater treatment plants are designed to collect sewage, treat it, and then discard the “clean” water to surface waters.  Many are also designed to discharge the sewage directly to the receiving body in emergency situations to protect the collection system.  There will be no waste water treatment in TEOTWAWKI.  Thus, any sewage that is still collected in the system is going to be discharged directly to a surface water.  You do not want to be downstream of this. Even if the collection system is not operational, massive amounts of human waste and trash are going to find their way into our lakes and streams.  As a result, being located upstream from these pollution sources is crucial.  The potential for contamination is massive.

This contamination can affect both surface water and ground water.  Recently in Colorado, many wells and springs were contaminated after being inundated with flood waters containing raw sewage.  Once ground water is contaminated there is little that can be done to remediate the source.  Instead, one must treat that water before use.  By locating yourself above potential contamination sources, you are protecting the long term viability of your water supply.

As described in the recommendations section below, the best way to avoid both water quality and water quantity issues is to locate yourself as high as possible in your water basin.


The issues described above can be avoided and mitigated as described below.

  1. Research

    There are many resources available to people who want to learn about where their water comes from and what factors influence the flow in nearby rivers, lakes, and streams.   A good starting point is U.S. Geologic Survey.  They maintain stream gages across the country.  This information can give you a general idea of the average flows and the severity of droughts and floods.  Sometimes, they can even show you how the flow of a river has changed as a result of a particular water project coming online. 

    The next level of research would be to find out exactly what factors influence your water source.  In Colorado, the Division of Water Resources maintains a massive database of water rights and diversion records.  There are also maps that show the location of various water rights.  You can use the maps and the water rights database to identify major diverters as well as the presence of transbasin diversions.

    It is also helpful to contact a local representative.  In Colorado, the state is divided into water districts.  Each water district has a water commissioner whose job it is to be intimately familiar with the water rights in that area.  If your state uses a different system, you can try talking with your regional water or natural resources office.  Regardless of the exact system in your state, there will be people who can answer your questions.

    Water is a huge issue in most western states, so there is often a large volume of information available simply through a google search.  Information about large water projects can typically be obtained through google.  You may even be able to find information about operating protocols. One word of caution, however, is that many states protect specific information about dams and large water projects because of security concerns.  At different times, I have been required to submit information about my work affiliations and need for information regarding certain dams before being granted access.  I can only assume that this information is being stored somewhere.  Moreover, be smart about the search terms to use when looking for this information so that you don’t inadvertently get flagged because it looks like you are doing something nefarious.

    To the extent that you can, I would also recommend contacting a water rights attorney.  This is particularly true if you are planning to spend any significant amount of money on a retreat.  While attorneys aren’t the most popular people, water rights attorneys are a rare breed and are extremely knowledgeable about water issues.  Many are also politically conservative and would be happy to help if they can.  Because every state is a little different, you may have to make a few calls before you get to the right person, but you will be glad you did.   The bottom line is that you need to inform yourself.

  2. Seek out Headwaters Areas

    If you are looking to relocate or purchase a retreat take time to look for properties in headwaters areas (i.e. the origins of stream and rivers).  The higher up you are in the basin, the less interference you can expect from other water diverters.  This is important for both water quantity and quality. I cannot emphasize enough how important it is to position yourself so that your water security is not dictated by actions of someone upstream of you. There is no doubt that water will be a serious source of conflict during a prolonged TEOTWAWKI situation. You can keep yourself out of these conflicts by strategically locating yourself and by treating this resource with respect to avoid undue attention from downstream users. This may be less important in areas east of the 100th Meridian where there are fewer water scarcity concerns, but fewer upstream diverters also means fewer contamination issues.   

  3. Plan your irrigation practices

    Another important thing to consider is how you will irrigate your fields.  Today, more and more, farmers are trading-in their flood irrigation for pressurized drip irrigation systems and sprinklers. These systems are great in that they conserve water and can reduce labor costs.  However, without a way to pressurize these systems, usually by pumps, they will be of little use when SHTF.  As a result, anyone planning to rely on irrigation to grow crops should construct an irrigation method that relies on gravity, even if they don’t plan to use that system pre-TEOTWAWKI.  This can be a massive undertaking requiring serious earth moving and planning in order to maintain the proper gradient.  Consequently, it will be much easier to do this work with earth-moving equipment now than with a shovel once SHTF.  While you may not want to use this method today, you will be glad that you have this setup when you are unable to run your pumps.  Moreover, as we all know pumps make noise and may draw unwarranted attention.

    I do not claim to be an experienced irrigator, but I think this is a very important consideration that may get overlooked.  Many preppers, including myself, have spent considerable time, money, and energy learning to grow and preserve their own food.  These are great skills and can help with setting food away, but in a prolonged event people are going to need to continue producing food.  This can only occur if there is sufficient water.  For land west of the 100th Meridian this requires irrigation, and irrigation requires planning. I urge you to consider how you will irrigate your fields when STHF and electricity is scare or entirely unavailable.

For those who don’t have the luxury of a dedicated retreat, rainwater harvesting is a great option. Homeowners can easily set up a system to capture rainwater using their existing gutters and downspouts. The Internet is filled with ideas on this point. It is important to know what, if any, legal restrictions may exist pre-TEOTWAWKI. The following link is a good resource for learning about your state’s rainwater harvesting rules, if any : Colorado is unique in that rainwater harvesting is largely illegal, except in narrow circumstances that require a permit. As I currently understand it, this rule is largely unenforced. Regardless, folks in Colorado may want to hold off on installing their system until it is needed. Obviously, these rules will go out the window during TEOTWAWKI, but you don’t want to bring negative attention to yourself in the interim.

As I hope I have conveyed in this article, you need to be very careful about the water source you plan to rely on.  Looks can be deceiving.  Today’s roaring stream could be TEOTWAWKI’s dry creek bed.  Educate yourself and thrive.