In some cases, such as major flood events, it can seem like one of nature's great contradictions that you are surrounded by water but have nothing safe to drink but that is often the case. Contaminated flood water is not safe to drink. An earthquake can break water mains and sewer pipes, causing water contamination and even modern-day water treatment plants can fail for any number of reasons.
Water is vital for life. We all need to have water to drink and we all need that water to be as free from contamination as possible. If you happen to find yourself in the unhappy circumstances of having no safe drinking water, or the only water available is dirty and possibly contaminated, you can make a simple sand filter and remove most of the water turbidity. The water will still need to be boiled for between 3 to 10 minutes, depending on contamination levels, before it is safe to drink. It may not taste very nice or be absolutely clear but it will be safe to drink and it will sustain your life. One complaint with drinking boiled water cold is that it tastes flat. This is because a lot of the air in the water has been lost during the boiling process. This can be overcome by aerating the water again by pouring from one container to another, at some height, to mix air back into the water. This will improve the taste greatly.
There are many commercial water filters available that range in price and affectiveness. Many will require expensive replacement cartridges if in use for extended periods and these can work out to be an expensive luxury in some cases. There is one very simple water filtration system that can provide safe drinking water continuously for months and years. This is an unglazed clay pot water filter wich is simple to make and easy to maintain.
Nature does a very good job of cleansing water for us and it falls from the sky for free all we need is a catchment and a storage system. The average suburban house roof can provide enough clean water for the whole household and garden, including clean drinking water, if the catchment is large enough and the storage tanks have enough capacity to last through dry periods. I intend to write a full article on rainwater harvesting and storage soon But I will look at some of the concerns some people might have here.
Air pollution may affect the water quality or alter the pH (acid rain). This can be mitigated by using a first-flush bypass system that diverts the polluted water away from the storage tank before collecting the pure water that falls afterwards. Most airborne pollutants will be gone in minutes, leaving clean water that is safe to drink. The first flush diverters have a spigot attached and a drip release system so that the polluted water will drain out between rain events or can be used on the garden, which resets the system for the next rain shower. These systems are so simple that a home handy-person could put one together quite easilly.
A first-flush system will get rid of almost all airborne and rooftop pollutants from collected rainwater.
In many places there is also a problem with leaves and other material on the roof getting into and blocking gutters and causing some problems with rainwater, as well as creating a . There are a number of different gutter-guard systems around but many can cause more problems than they solve. After doing some research, I have decided the best possible system is a fine metal mesh that covers the gutter but must follow the same angle of pitch as the roof. This will reduce dramatically the amount of leaf build-up on roofs and may even help reduce snow build-up as well in those areas where snow can be an issue. Fitting these micro-mesh systems is easy enough but getting the slope or pitch to match the roof pitch may require re-fitting or replacing existing gutters. This may be expensive but will save on maintenance for many years. I would combine this with a simple down-pipe mesh cover that operates in a similar manner and that should keep most impurities from entering the tank.
Micromesh guards will help to keep impurities out of rainwater and minimise maintenance
Rainwater storage tanks come in all shapes and sizes to suit almost every application these days. The traditional tank in Australia was made from galvanised steel but the newer plastic tanks are far more durable and will not rust out. There are modular units that can run along a wall or fence-line if space is an issue. I would suggest that the more water you can store, the better off you will be, so choose you tanks wisely and go for the bigger ones wherever possible. Water is vital for all life. Water is also becoming a commodity. If we can harvest our water on our own property we reduce the stress on municipal water supplies as well as reducing our water bills and at the same time, we can ensure that we have a source of safe drinking water, no matter what happens.