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.

Septic Tank Problems

Septic systems range from the very simple to the extremely complex. Even on the simplest septic systems there are still many things that can go wrong. If you believe that septic systems are something you bury and forget about, then I guarantee that you will come across many of these problems. There are simple things anyone can do to keep their septic system running properly for decades.

First a general description of a septic system. The system starts where the common drain leaves the house. This drain can go to a municipal sewer or to an individual septic system. The water flows by gravity into the septic system. The inlet to the septic tank is protected by a T shaped baffle. It is open on the top and bottom. It is designed to contain floating debris in a small area and to direct solids to settle down towards the bottom. The water is contained here where solids settle out to form a sludge layer and floating objects form a scum layer. In between there is a clear zone where the water has very few solids. The water in the tank is treated by anaerobic bacteria. The bacteria break down organic compounds in the water until there is almost nothing left.
The water leaves the tank through another T shaped baffle on the other side of the tank. This one goes down to the clear zone and allows clear zone water to exit the tank without coming into contact with the scum layer. Some tanks have a septic pump, the pump is installed on the opposite side of the inlet and at the expected height of the clear zone. Larger tanks might have a dividing wall to keep sludge and scum on one side and clear water on the other side.

Septic Tank, Septage, scum, sludge, clear, zone

Basic Septic Tank Design (source: biozoneseptoc.com)

The sludge layer if not removed every three to five years can cause a major failure of the entire system. Not everything can be broken down completely.  There are always things that either never breakdown or breakdown too slowly and they accumulate.  The sludge layer will eventually reduce the capacity of the tank and the solids will block the inlet or the outlet of the tank.  The sludge layer will be a rapid problem if the people using the system treat the toilet as a garbage can.

The scum layer is all the floating solids the get flushed into the system. Grease and oils cause a large part of the scum problem. But they are far from the only culprits. Cooking oils and grease coat the walls of the pipes and tanks and slowly reduce the size of the of the inlet and outlet eventually blocking them, and you can see how that is a problem.

The drain field is where the treated effluent gets released back to the environment. It may be called something else like a tile bed or weeping tile. They are usually subterranean but can sometimes be on the surface. Regardless there are still buried pipes and they are easy to collapse if you drive a vehicle over them. Lawn tractors are OK but even compact cars are too heavy for the shallow plastic piping. If the piping becomes cracked or even a section collapses then pipe will become blocked with dirt and your waste water will have nowhere to go except back into the house.

Hydraulic overloading is the technical name for putting too much sewage into your septic tank.  This can happen if you have a party and there are more people using the system or if the sludge layer reduces the capacity of the tank.  The end result of overloading is that poorly or untreated sewage leaves the system negatively impacting the surrounding area.

Leaks are bound to occur with age.  You can also create leaks by driving over the tank and excavating too close to the tank.  Leaks are a huge problem once they occur.  The groundwater and soil contamination is extremely expensive to clean up.  You may also be liable for damage to the neighbor’s water supply depending on the riparian laws where you live.  A leaking tank needs to be replaced immediately.

Proper maintenance will prevent most problems.  The worst thing anyone can do is to bury the septic system and forget about it.

Water Security Before, During & After Hurricanes

People often neglect to consider the security of their water supply prior to a hurricane, there are many other pressing needs for preparation, namely protection of property. Because this week is National Hurricane Preparedness Week I wanted to discuss how hurricanes can disrupt water systems and water supplies. Water security is essential when talking about hurricanes. Actions taken before the hurricane, during and after the hurricane all play a significant part in maintaining your access to clean, safe drinking water.

Hurricane Ivan: Image source nationalgeographic.com

First a note on evacuations. I’m not going to tell people to stay or go when it comes to evacuating. Make that decision for yourself.

What can be done before a hurricane hits? If you are on a well, make sure your well is sealed properly. This is normal well maintenance. Your annual maintenance and inspections are your first defense against well contamination. With a hurricane the main culprit is the rain and the storm surge. Surface water contamination with bacteria, chemicals and salt can make your well very unfit to drink. Prevention through proper maintenance is the best barrier against contamination. If you are on a municipal water system, shut off the water to your house before you evacuate. This will prevent leaks and the subsequent damage from the water entering your house. It will obviously not protect you from rain/wind/flood/storm surge damage.  Also, it is a good idea to temporarily cap the connection from your house to the sewer or septic system, this will prevent overloaded waste systems back flowing into your house.  These precautions need to be done whether you bug out or not.  This is the time to store water.  When the water coming into your house is clean and drinkable.  Store as much as you can, it could be the difference between life and death.

Storm Surge Diagram: Image Source worldlywise.pbworks.com

During the hurricane, if you don’t evacuate to a safe area, you need a backup supply of water. Continue reading

Septic Tank Management

Homeowners are responsible for maintaining their septic systems.  It not only protects the investment in your home, but also protects your water supply and those of your neighbors.  You don’t want to be the cause of major ground water or surface water contamination because of a malfunctioning septic tank.  The liabilities are potentially huge and your homeowners insurance may not cover you if you didn’t do the required maintenance.   It will also make selling your home difficult,  I personally have walked away from houses I wanted to buy because the septic system was not in proper working order.

Septic tank management can be very simple. If the tank has been properly constructed and installed very few interventions will be necessary and the interventions will primarily be inspections.  The major components of a septic system are a collection pipe from the house, the holding tank, and the drainage system (usually a field).  The collection pipe is the final pipe leaving the home that contains all the household waste water.  This part of the system is identical for people connected to a municipal sewer except for where the pipe goes. Continue reading

Water Quality Is Subjective

Clean water is clean water right? If I don’t get sick when I drink it that means every one can drink it right? The truth is not everyone has the same body chemistry. Everyone has a slightly different tolerance and/or sensitivity to contaminants. This could be an allergy to something in the water but it doesn’t have to be that severe. Children are often more susceptible to contaminants in water, as are the elderly and pregnant women. In the past when water systems have been contaminated, the two populations most likely to get very sick and or die are your children and seniors. Honorable mention goes to people with weakened immune systems which are almost always at greater risk.
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Well Disinfection: What To Do After Contamination Occurs

It is a common misconception that ground water is safe from contamination. This simply is not true. Wells can easily become contaminated if the proper maintenance isn’t taken and even with proper maintenance they can become contaminated during an emergency like a flood. See my article on Ground water and Wells for the proper maintenance of wells to prevent contamination.

Wells can become contaminated two separate ways. The first one is harder to control.  It happens when the entire aquifer becomes contaminated. This can happen when there is an environmental spill of something (anything really) that percolates into the aquifer in or around the recharge area. This could be on your property or a hundred miles away. It all depends on the aquifer.

How Contamination Enters A Well: From: http://www.health.gov.on.ca

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Back Up Source of Water

Do you have a backup source of water? I do. I am also preparing for the ability to treat water at home. Not everybody will have the knowhow/space/desire to follow my plan, but there are things you can do to protect yourself in the event of a prolonged disaster or emergency. Let’s look at what happened in the town of Walkerton. In may of 2000 there was a prolonged and persistent contamination of the public water supply. The causes of which are well known and on the simplest level; the human, mechanical, and monitoring systems broke down. Seven people died directly from drinking contaminated water and 2500 people became seriously ill, some are still sick to this day from the resulting kidney damage. This was human made disaster, the same thing can just as easily come from a natural disaster. Continue reading