Ageing Infrastructure

What do you think is the most likely reason for a water grid shutdown?  It isn’t terrorism and it isn’t pollution. The answer is, the age of the infrastructure used to deliver the water or collect the sewage. Think about the city you live in. Chances are it has existed for hundreds of years, if not longer. Most cities water systems grow in phases. They keep adding to the network every year as the population grows. The end result is most cities have infrastructure that range from less than a year to hundreds of years and with many different materials. I have seen water mains made of wood in service as late as 2011. Like any piece of equipment it all has a useful lifespan, beyond that lifespan failures become increasingly more likely to be catastrophic. The result is a large volume and dollar amount of material and equipment that needs repairs or to be replaced.

Wooden Water Main circa 1909 source www.nytimes.com

Wooden Water Main circa 1909 source http://www.nytimes.com

Normally the stress on water systems comes from population growth.  A water main that was ok in the 1980’s may not be large enough for today’s population.  As cities infill and build higher density buildings they frequently overburden the water systems.  Either causing contamination or total failure of the system.

Older equipment is also more susceptible to natural disasters, terrorism and human accidents. These three things can break a new system too, however they don`t have to try as hard with the older systems.

Climate change is having an affect too.  As severe weather events are on the rise, storm sewers might be found lacking, as was the case in Calgary, Alberta and Toronto, Ontario recently.  The system was grossly undersized for the amount of rain that fell.  They said things like “it was a month’s worth of rain in one day” on the news.  When the fact is, it once was a months worth of rain, and is now something more frequent, lets say a weeks worth of rain.    I’m not suggesting we build our systems to meet a 1000 year storm, but I am suggesting that our current idea of a 100 year storm may be an underestimation and that the error is getting worse.  To bring it back to infrastructure, if we are built to the current 100 year storm levels, what happens if the 100 year storms are getting worse?  We will find out in the not too distant future.

Calgary, Flood, Floods, Water

Flooding In Calgary AB 2013 source: http://www.newinfills.ca

What are the options for people to take? The first and most important thing to do is to plan ahead and replace older parts of the system before they fail.  A $50,000 job to replace an old section of pipe at a time you choose is a lot cheaper than waiting for it to fail at the time you are least prepared.  If you are connected to a public utility, ask them about their equipment replacement plan.  If they are not looking 25 years into the future or longer then ask them why not? If you have private systems, you need to ask the same questions.  Can you afford to replace the septic system when it fails? Or can you afford to dig/drill a new well when the casing cracks?

As you can probably surmise the addition of more people + more rain + more water and more sewage means system failures will become more frequent and probably for longer periods of time.  What does this mean to the average person?  Plan for system failure.  Have a backup system ready to go when it does.  Know the age of your equipment and it`s expected lifetime. That way you wont be caught off guard.

Advertisements

Cleaning Up Contamination with Super Chlorination

Super chlorination is a technique used to clean and disinfect water holding vessels that cannot be washed in the traditional sense. This is different from your standard disinfection, which is for cleaning the water, not the container. Super chlorination is used when reservoirs become contininated with microorganisms or have been emptied for any reason (indicating possible esposure to contamination).

Super chlorinating is simple. On a very basic level, it is just adding a large amount of chlorine to a reservoir either as a wash applied directly to the wall or as a very strong chlorine/water solution which fills the entire reservoir.
On a more specific level, it is dependant on the strength of the hypochlorite and the amount of time the chlorine is left in direct contact with the container. The stronger the chlorine the less time required. For example, if you decide to spray the walls with straight 10% sodium hypochlorite then there is almost no time required. Whereas the normal chlorine levels in most municipal drinking water systems is not enough to ever disinfect the vessel it is in. Those low levels of chlorine will only protect the water from contamination in a reservoir that is already free of contamination.

Now you might be asking how to figure out how much chlorine to add to make super chlorinated water. If you think all you need is to dump a large amount of chlorine in then I will point out that releasing large amounts of super chlorinated water into the environment is illegal in most jurisdictions. So it is necessary to calculate how much dechlorinating agent is needed. The easiest way to know the dechlorinating needs is to measure the amount of chlorine added. In order to save money or time it is best to calculate the ammount of chlorine necessary.

50 mg/L (50 ppm) of available chlorine is a great place to start. 50 mg/L left for 24 hours will meet the best pratices and standarized procedures for most jurisdictions in North America. Below is a table outlining how much chlorine you need to add for various volumes of water.

image

Super Chlorination Volumes at 50 mg/L (from the City of London Port Health Authority)

From this chart you can see exactly how much chlorine to add. Add the hypochlorite solution when the system is haIf full. Then fill the tank or reservoir the rest of the way with clean water. If you are disinfecting something with plumbing, like a building or a boat, then make sure the super chlorinated water makes it to each cold water faucet by flushing until you can smell chlorine (or can measure it). Do not flush the hot water faucet. all you will do is waste chlorine and hot water.

This procedure will disinfect any reservoir. Regardless of the levels of bacterial contamination, because if it doesn’t work the first time repeat the process until it does. The most likely culprit if super chlorination doesn’t work the first time is that a pipe connected to the tank wasn’t flushed completely.

Whether you have a large tank of reserve water or your rain barrels start growing dangerous microorganisms, you may need to super chlorinate one day.

Disinfection with Potassium Permanganate

Potassium Permanganate is a very versatile chemical. It can be used for disinfection, removing hardness, removing iron and manganese. It has another health related use, it can be mixed into a paste and used as a topical salve for athlete’s foot (or similar problems). As a result potassium permanganate is a great addition to any emergency preparedness supplies.

Potassium Permaganate has the chemical formula of KMnO4, and it comes as a deep purple dry powder. This chemical is a very powerful oxidizer and it should not be stored anywhere near acids or fuel sources or it could result in fires, explosions and/or toxic gases being formed. Explosives is another use of this chemical (one which I will not be explaining here). This chemical can be stored for over a year if it is kept clean and dry and in a sealed container.

20130109-230655.jpg

Before touching the dry powder, make sure you wear a particle mask (ideally a N95 or better). This chemical will irritate the airways if inhaled directly. Also the powder once mixed with water becomes a powerful dye. It will stain clothes permanently, stain skin temporarily and cause corrosion on any metal or masonry it touches. Anything that becomes exposed to a potassium permanganate solution becomes brown, a similar shade of brown to a henna tattoo.

To make a topical treatment with KMnO4 mix the dry powder with water until it has the consistency of playdoh. Apply the mixture on the affected area and repeat as necessary. Remember that I am not a doctor and I am not giving medical advice. I am only outlining that this chemical CAN be used for medical purposes. Whether or not you SHOULD use KMnO4 for medical applications is not something I can tell you.
.

20130109-231521.jpg

Potassium permanganate is very similar to sodium hypochlorite in the sense that they both disinfect water through oxidation. Disinfection of drinking water can be achieved by adding it to the water until the water turns pink. The pink in the water is the residual potassium permanganate. Meaning that there is nothing left to use up the chemical and any bacteria has been used. Think of the pink water as being similar to the point where you can smell bleach when using sodium hypochlorite for disinfection. Just like with the smell point of bleach has surpassed the disinfection point, you do not need to keep adding KMnO4 until you see pink. Disinfection has occurred well before you can see a lasting pink tint to the water. Using the color change is a simple and easy to remember method for disinfection of drinking water. And if the pink tint disappears at any time then you know you need to add more of the chemical to redisinfect the water.
If you want to avoid pink water and spend less money on chemicals you can buy a testing kit for manganese. Most kits can measure the residual levels of KMnO4 at levels well below the pink water threshold and well above the disinfection requirements.

20130109-231222.jpg

For better results with disinfection it is best to filter the water through a greensand filter. Now this is not an indication of the color of the sand (it is actually black in color). Greensand is an activated filter media designed for removing iron and manganese through a process called ion exchange. The good news with a greensand KMnO4 combination is that the potassium permanganate will reactivate the filter media.

One thing to note is that potassium permanganate once added to water will make the water more corrosive. If the water is very pink it can also stain any container it is stored in. The pink water is perfectly safe to drink. I mean the water is not dangerous because of the pink coloring. It may however be dangerous for another reason or contaminant.

Another thing to note about KMnO4, is that if you add it to chlorinated water it will form a percipitate (solid). This is manganese dioxide, it is harmless except it will consume all the available chlorine in your water leaving you open to contamination from microorganisms.

With a few simple precautions KMnO4 is an excellent chemical to have on hand. It can be stored longer than sodium hypochlorite (bleach) and it can be added directly to the water unlike calcium hypochlorite. It also is very easy to see when enough of the chemical has been added. If there is a lasting pink tint that doesn’t disappear with time then the water has been disinfected.

When it comes to disinfecting your own drinking water, always be careful with the quality of chemical you use. They are not all created equal. The north american standard for chemicals used in drinking water is NSF/ANSI 60. Choose chemicals that meet this standard above ones that don’t. The will be significantly safer for your health and well being.

As with all my disinfection articles, I will remind you to always drink the safest water you can and combining treatment techniques is the best way to achieve safe drinking water

Lids On! Teaching Children Survival Skills

Children are excellent at picking new information however children often find learning survival skills difficult. Even when they do remember what to do to survive, will they remember to use the skill when they need it?
Educating children for wilderness survival needs to be very simple and driven home with a demonstration. Take for example the simple skill of having and wearing a warm hat. Exposure to the elements is something that is very dangerous. It can be fatal to adults and children are even more sensitive.
This may seem like a simple thing, wearing a hat is definitely a simple thing but have you ever tried to keep a hat on a child under ten years old? This is an almost impossible task, except when NOT wearing a hat is too painful like in extreme hot or cold temperatures. Waiting until it is too painful before you put on a hat might be too late in a survival situation.
Here is an experiment you can do with kids to show them the importance of keeping insulated. It is called the Lids On experiment.

What you will need is very simple and you may already have them in your house.
1) Two pots of equal size with lids.
2) Two thermometers. It can be done with one thermometer but it is more dramatic with two. More drama increases the likelihood of them remembering the lesson.
3) Stove with two equal sized burners
4) A timing device, watch, stopwatch, egg timer or a normal clock will all be
sufficient.
5) A measuring cup.

The procedure for the lids on experiment is very simple as well. And there are many possibilities for side lessons some of which I will point out.

1) Measure out the same volume of water and pour it into each pot.
2) Bring both pots to a boil at the same time.
3) Turn off heat source for both pots at the same time.
4) Measure the temperature of the water and note the time.
5) Leave the water to cool on the stove. But leave one pot with it’s lid on and one pot without a lid. You can do the entire experiment again and leave the pots outside and watch the temperature drop faster.
6) Have the kids guess which will cool faster, lid on or lid off?
7) After approximately 10 minutes return and measure the temperature of both pots.

The pot without the lid will be significantly cooler. This is because the lid traps warm air around the top of the boiling water. (Just like a hat does for our heads). The water not protected by the insulating effect of the air is exposed to the elements and heat is actively lost very rapidly. (Just like our body heat when we are improperly protected from the elements).

This experiment can be more than a survival lesson. You can expose children to the safety precautions around the stove/cooking, the physical properties of water (why it boils and at what temperature), how to tell time or read a clock, how to measure volume/temperature and how to ask a scientific question (hypothesis) and test for an answer.
I would only add more information about the experiment if the child or children are really demonstrating that the survival lesson has been learned and internalized. Saying the phrase “lids on” after the experiment has been completed when the child is putting on a hat will help drive the message home. So will playing a Simon Says type game where the commands are Lids On and Lids Off. Lids On instructs that they put on a hat and act warm. Lids Off instructs that they take off the hat and act cold.
The repetition after the experiment will be the best thing you can do to maximize the chances that they will remember to put their lids on when they really need to.

Evaluating Risk and Preparing Accordingly

From extreme weather related disasters to economic collapse, danger is a very real part of daily life. Risk is part of every activity humans do everyday. Risk can apply to our safety, economic, political, environmental and social spheres. There is a risk when cooking breakfast, there is a risk when driving a car there are risks when you invest money and there are risks when you tell someone you love them for the first time. Basically, because life is so risky, people feel the need to mitigate risk wherever possible and prepare for when disaster strikes. Some types of risk human beings are very good at evaluating, other types not so much.

Natural Disaster: Tornado  (source: tornado-facts.com)

Natural Disaster: Tornado (source: tornado-facts.com)

Risk is made up of two parts. The severity and the frequency. Both the severity or consequences and the frequency are essential for understanding the risk. Events that have a low severity and a low frequency therefore are low risk and are generally considered to be safe.

Risk Matrix for Classifying Risk Types (source: erris.org)

Risk Matrix for Classifying Risk Types (source: erris.org)

The danger comes from events that have either high severity or high frequency (or both). If an event has high severity and high frequency, it is necessarily very dangerous. A great example of these types of events are hurricanes. They happen every year and cause significant damage every year. Even if you aren’t directly affected by a hurricane, you are reminded of the last time you where hit with every hurricane.
Where humans become confused about risk is when we are afraid at the same time. If we are for example afraid of nuclear meltdown, then we will rank a nuclear meltdown as a more significant risk. This is referred to as the dread factor. The dread factor is a dangerous thing to ignore. With finite resources for disaster preparedness and risk reduction giving into fear will cause a real risk to be ignored. I’m not suggesting that the risks we dread are not dangerous, just that it is easy to over inflate their importance to our time, money and effort.

Humans have a technology bias. We feel that man made disasters are inherently riskier. This is partly due to the dread factor regarding man made disasters but it is also due to a willful down playing the risk from natural disasters. Severe weather can happen anywhere on the planet and happens very frequently.  Man made disasters can also happen anywhere, but they do not happen nearly as frequently.

Man Made Disaster: The Kuait Oil fires (source: disasterium.com)

Man Made Disaster: The Kuait Oil fires (source: disasterium.com)

Statistics are necessary for knowing what the likelihood of any event occurring could be. The good news is you don’t need to be particularly strong in math to do this. What is really important is the ranking and directing more resources to the top ranking items.
Statistics can also be used to highlight risk or hide risk. That is assuming people will read the statistic correctly. The term 100 year storm is often interpreted as a storm that comes every 100 years. It actually refers to a storm that historically only occur once in a 100 year period. The difference is you can have a 100 year storm occur two years in a row or more.

I have found some ways to learn what you are most at risk for/from. The news is a good source, if you read about forest fires nearby, then you are probably at risk from forest fires in general. Try to read the news as factually as possible. Ignore any hype and sensationalism.

Next, ask your family for a list of any health problems and causes of death. Many diseases are genetic and knowing what you may affect you can give you time to delay or stop it all together. If all your grandparents died of heart disease, then action today can prevent that fate for you.

Next, call your insurance company. Insurance companies are in the business of estimating risk. The more expensive the coverage is, the more likely that event is to occur. Another question to ask is if there is anything they won’t cover for where you live. If an insurance company won’t sell you flood insurance, I can almost guarantee that you live on a flood plain and a flood is in your very near future.

Finally, most risk can be averted just by paying attention. When we are alert and attentive we will act sooner and are significantly more likely to be prepared.

Can I use a storm-water pond as a back-up source of water?

Storm-water ponds are the closest alternative source of water for many people living in urban areas. In an emergency this source of water may be all that is available to you.  Eventually any water you have stored will be consumed and the water in a storm-water pond may be the difference between life and death.  With the proper treatment your local storm-water pond can be a great backup source of drinking water.

Industrial storm-water pond (source: info.evergreen.ca)

Storm-water presents a unique set of challenges during treatment. Because storm-water ponds collect surface water, the water is exposed to all the contaminants on the ground in the catchment area. This includes but is not limited to pesticides and fertilizers applied to lawns, motor oil and gasoline leaking from vehicles and litter like cigarette buts. It all ends up is the storm-water pond. Those chemicals are already in storm-water ponds on a normal day. During an emergency there may be additional contamination from sewage runoff from an overloaded or broken sewage system. The water in the pond will also contain all the microorganisms like ecoli, giardia and cryptosporidium normally in surface water. Any one of these will make you very sick if you get infected with them.
Finally, there will be high levels of nitrates in storm-water ponds. Too much nitrates consumed by young children can cause blue baby syndrome.

The first step in treating water from a storm-water pond is straining. Straining the water through a cloth or loose sand filter will remove large particles (ones you could pick up with your fingers). Remove as much of the suspended particles from the water as you can. Straining the water first will extend the life of your proper water filter.

If you have a clarifying agent like aluminum sulfate, this is the best time to add it to the water.  It will make contaminants too small to be filtered become attracted to each other and become significantly larger.  Larger particles are easier to remove from the water. Let the water sit still for at least 30 minutes without disturbing it.  All the newly formed large particles (called floc) will sink to the bottom.  When you take the water from this container, make sure you leave the majority of the settled material at the bottom of the container.

Urban Storm-water pond (source: greenbmp.blogspot.com)

The next step is to filter the water. Filter the water even if it looks clear, the human eye is five times too weak to detect dangerous levels of particles. Filter the water at least once through an activated carbon filter. Activated carbon is known to remove many different chemicals from water including pesticides, chlorine and fluoride. Activated carbon is not the same as charcoal. Charcoal is similar, it can remove toxins from water but it is nowhere near the efficiency of activated carbon.

The third step is oxidation. Oxidation will help with disinfection as most disinfectant chemicals are also oxidizers. Chemicals like sodium hypochlorite and potassium permanganate are both oxidizers and disinfectants. Oxidation will break down many of the remaining contaminants and inactivate many of the remaining bacteria. Keep adding the oxidizer/disinfectant till you can detect a residual after 20 minutes. The 20 minutes is the minimum you should wait for a gallon of water. Wait longer for larger volumes. This is because oxidation is a chemical reaction that isn’t instant. It needs time to complete the reaction.

The fourth step is to filter the water again. Filtering again is necessary because the disinfection/oxidation step will create some potentially carcinogenic byproducts. We filter before oxidation to minimize the amount of chlorine (or other chemical) and to limit the possibility of forming dangerous byproducts. We filter the second time to remove any byproducts that have been formed.

The final step is to boil the water.  This will help with disinfection, but the main goal of boiling at this point is to remove any volatile chemicals.  Any chemical with a boiling point lower than water will be removed after boiling.

A note about disinfection.  If all of these steps are followed there is no need for a step dedicated for disinfection.  Between the oxidation and the boiling of the water any microorganisms will be inactivated.  If you are storing the water for a long time then add some sodium hypochlorite for a residual disinfectant.  The residual disinfectant will prevent the water from becoming recontaminated before you drink it.

One additional possible step is to aerate the water.  Ponds are frequently stagnant.  Stagnant water is green with algae, it smells bad and tastes worse. After the water is made potable, transfer the water back and forth between two glasses. This adds oxygen to the water and will make the water taste better.

This may seem like a lot of work for something as small as a storm-water pond.  What I have described are the basic steps to turn the potentially toxic water in the pond into clean and safe drinking water.

Terrorist Attack and Water Systems

Water systems are distributed networks of pipes, pumps and reservoirs. Like all distributed networks they can be very difficult to protect from vandalism and terrorist attack. There are two broad types of attacks that could hit a water system. The first type is an attack on the quantity of water available (physical supply) and the second is an attack on the quality of water. The end result of both types of attack is a lack of potable water entering your home.

The greatest defense for a water system is that most of it is underground. It is very difficult to access most parts of water distribution systems. Even for the operators of the system it is time consuming and disruptive to the wider community. If anyone unauthorized to dig in a road to access a watermain they will be reported to the authorities in the form of complaints about traffic or noise.
I think it goes without saying that depending on public complaints to defend against terrorism is nowhere near secure.

Water Treatment Plant (source: wikipedia.org)

The exposed parts of water systems are water treatment facilities, reservoirs and fire hydrants. These are the points where the system is at the surface and easily accessible. These different points also offer different security concerns.

Treatment facilities are as secure as any factory or industrial facility will be. The treatment facility I work at is always locked and there are a limited number keys. Then there is an electronic alarm system which brings a human on site if there is an intrusion alarm. There is also a human dispatched if the communication link is broken. A large city water treatment facility will most likely be manned twenty-four hours a day. The biggest weakness here is that properly armed people can force their way in and destroy the building if they so desire. Or they can contaminate the reservoir on site (if they know how).

Reservoirs of treated water are next most likely place for a terrorist attack. The biggest weakness here is that reservoirs are almost never manned during the day. They will be visited most days, but rarely will people be there all day. The good news is that water in reservoirs is monitored constantly(usually) with automatic analyzers. Reservoirs can be destroyed, and the water within wasted. Or the quality of the water can be destroyed this is where chemicals could be added easily.

The remaining pieces of the system are fire hydrants. Fire hydrants pose a unique risk to water security. It is very easy to add chemicals to a fire hydrant. It is however not easy to get that chemical into the water supply. This is because of the construction of the hydrant itself and the pressure in the system. There is a valve at the bottom of the hydrant which isolates the water. In order to add chemicals to a fire hydrant you also have to lower the system pressure which is rarely easy to do undetected. At this point I want you to remember the scene in Batman Begins where Sandman is dumping his psychotropic drug into a cracked watermain. I don’t expect realistic depictions from the movie, I do however want you to know this is nowhere near realistic. Watermains are pressurized, when they crack water shoots out at anywhere from 50 to 100psi. This is enough to erode foundations of buildings and the all soil around the break creating massive sinkholes. It is not something you can pour chemicals into. This is what it looks like when watermains break.

Just adding chemicals to water, is not as effective as it appears on the surface.  Most water supplies contain residual disinfectants, usually chlorine.  Disinfectants are highly reactive chemicals, they aren’t limited to just killing bacteria.  Highly reactive chemicals often react with other chemicals.  I am obviously oversimplifying the chemistry involved, but it is true that a large portion of any chemical added to water will be consumed by the chlorine in the water.

Adding Chemicals to Water (source: http://www.thejakartapost.com)

Cyber attack is another way water systems are vulnerable.  You may wonder why water treatment facilities are connected to the internet and the answer is for remote monitoring and control.  It may seem like an unwarranted risk having these facilities connected to the web.  It is not an unwarranted risk at all.  The likelihood of the automated system needing an intervention that cannot wait for someone to be onsite is greater than a targeted cyber attack. Keep in mind that even normal breakdowns of the watersystem can cause illness and even death.  These need to be responded to and are just as important as preventing cyber attack. I am not a technology expert so I will leave it to other people to suggest the best firewall setup.   Another thing to note about cyber attack on a water treatment facility is that even if the attacker is successful and shuts down the control computer, the facility can still be controlled manually.

Terrorism is something that needs to be addressed when it comes to water systems.  People inside and outside the system need to be aware of the risks and what can be done for protecting the security of out water.