Water Safety Module 2: Health Hazards in Wild Sourced Drinking Water

Toxic Algae Blooms

What is Wild-Sourced Water?

Wild-sourced water is any form of water that is not treated or processed by modern water treatment systems; this includes rivers, lakes, ponds, bogs, and seasonally temporary pools of water known as Vernal Pools. These can also include man-made ponds, lakes, and reservoirs. These are all sources of untreated water, which means that there is a potential risk of developing waterborne illness if consumed. Depending on the source, the surrounding environment, and even weather conditions that risk can range from low to very high. In this module, we will be exploring the various types of waterborne health hazards and where they are most likely to occur.

Overview of Types of Water-Related Hazards

There are three types Biological, Chemical, and Radiological. 

Biological Hazards: Consist of living organisms and their by-products that can make us sick. Chemical Hazards  

Chemical Hazards: Consist of toxic chemicals found in water, likely caused by pollution.

Radiological Hazards: These consist of radioactive materials found in water, very rare under normal circumstances. 

This module will focus on Biological and Chemical hazards as radiological hazards are typically very rare and the likelihood of you spending any time in a highly radioactive area is next to none.

Biological Hazards

Most biological hazards are caused by microorganisms including Viral Particles, Bacteria, and Parasites. In some cases water infested with these organisms can be visible, in a majority of cases evidence of these organisms will only be detected through scientific testing. What this means is even clear water can be loaded with harmful organisms that can make us sick if we drink it. Biological hazards come from a few sources; some are caused by organisms that are naturally occurring in the water, while others come from animal waste or dead and rotting animals in the water. Let’s explore some of the organisms that can be found in water and how they can make us sick.


This parasitic family of organisms is found all over the world and is known to be the leading cause of waterborne illness in the United States. These organisms live in the intestinal tract and cause severe diarrhea. This is spread by infected fecal matter (poop) entering waterways. While this is not incredibly dangerous to most people, those with weakened immune systems can become very ill. Humans and animals can remain contagious for many weeks after symptoms stop. Cryptosporidium is known for being very resistant to chemical disinfection, particularly chlorine.


This parasite only affects humans and other primates, but can be carried by other animals. It spreads the same way cryptosporidium does, however, it causes a far more severe form of gastroenteritis and will remain dormant for a week before causing an illness that if left untreated can last up to 6 weeks.


This waterborne parasite can cause gastroenteritis for 2 to 6 weeks, and in many people can cause illness for many years including chronic fevers, long-term gastrointestinal issues, loss of ability to absorb B vitamins, and breakdown of lactose as well as trigger autoimmune diseases. In young children, it can cause developmental delays.

Naegleria fowleri

Commonly called the “Brain Eating amoeba, this waterborne parasite causes a sudden and severe brain infection. While you can not become infected by drinking infected water, you become infected by inhaling microdroplets of water which can easily occur while gathering drinking water. This organism is commonly found in warm waters such as hot springs and warm ponds. Symptoms such as altered mental state, seizures loss of sense of smell and taste, and coma occur one to 9 days after exposure and death typically results in one to 2 weeks after symptoms begin. Treatment is possible with early detection though success will vary. 

Blue Green Algae

Blue Green Algae is not an actual algae but a type of bacteria called cyanobacteria. This is commonly found in stagnant water and is quite visible. Cyanobacteria produce cyanotoxins which cause a variety of issues including gastrointestinal distress, and vomiting. Skin, eye, and throat irritation can occur. The most severe symptoms come in the form of difficulty breathing and liver damage. This can be fatal in some cases, though fatalities typically occur more often in farm animals and pets. It is important to remember that portable filtration systems will filter the organism, but will not filter the toxin.


Shigella is a type of bacteria that is found in water that has been contaminated by raw sewage. Symptoms include Diarrhea, fever, stomach pain, and the feeling of having to move your bowels (poop) even when there is nothing left in them. While the primary symptoms last for about 7 days, irregular bowel movements can occur for months after the infection.


Norovirus causes severe gastrointestinal issues including fever, nausea, vomiting, and stomach pain; fevers are also common with norovirus. There are a number of ways to catch norovirus and contaminated water is high on the list. Fortunately, the symptoms of norovirus last around a day or 2.

Escherichia coli (E. coli)

E. Coli is a bacteria that causes relatively minor to severe bloody diarrhea. While healthy adults usually recover within a week, older or immune-comprised individuals can develop life-threatening kidney issues.  While this is commonly associated with contaminated food, this bacteria is found in waterways through sewage contamination and waste from infected animals.

This is by no means an exhaustive list but covers some of the most widely dispersed and common biological hazards. Many other organisms exist and produce similar issues, but as you can see from the examples listed issues can range from minor intestinal issues to more severe life-threatening illnesses.

Chemical Hazards

Chemical hazards are generally caused by anthropogenic (human-generated) pollution, like biological hazards, there are cases where chemical pollution is evident in most cases the chemical contaminants will exist without displaying any visible evidence. Chemical pollution can come from obvious sources such as industrial dumpage into waterways, but there are other sources that people don’t regularly think about. Farms are a major source of chemical pollution, and since farms are often located in more rural areas there is a good chance that pesticides, fertilizer, and animal waste (also a source of biological contamination) based contamination can make their way into popular outdoor recreational areas and waterways. Even local homes that use chemical pesticides and lawn fertilizers can be a source of chemical pollution. Pollution from these sources are mainly carried by the wind blowing loose contaminated soil when its dry and runoff into drainage pipes and local rivers and lakes during heavy rains.

I will not break down all the different potential chemical hazards out there but it is important to know that these chemicals very rarely make us sick through a single exposure, but can build up in our body over time causing a variety of health issues including but not limited to immune issues, fertility issues, specific organ issues, and cancer. 

Preventing Waterborne Illnesses

Preventing waterborne illnesses is possible by employing, you guessed it, Mindset, Skill Set, and Gear Set! In this section, we will briefly discuss some of those methods and we will take a deeper dive into each one in future modules.

Water Source 

As a general rule, you should be sourcing water from a clear fast moving stream as close to the origin of water as possible. However just because it’s moving does not mean it’s good water. As mentioned above areas close to industrial sites, farms, and large residential areas have an increased risk of being contaminated by biological and chemical hazards. In addition, a rotting animal upstream can be delivering a potent dose of biological contamination downstream. Stagnant water should be avoided, and stagnant water with evidence of algae should be avoided at all costs.

Boiling Water

Boiling water to a strong rolling boil is enough to kill most biological hazards, however, it will do nothing for chemical contamination or eliminate toxins created by certain microorganisms.

Chemical Purification

Chemical additives are an easy and cost-effective way to kill many microorganisms, however, they will not eliminate certain types and will leave your water tasting kind of funky. Chemical additives will not reduce any chemical pollution in water.

Filter Systems

Filter Systems are highly effective at reducing chemical and biological contaminants. It is important to understand what each filter is rated to remove as many filters (especially inexpensive ones) will not filter out viral particles. As far as I know, there is no small retail filtration system to remove algae toxins.

UV Purification

UV purification is very effective at removing biological threats, but takes time and relies on a power source.

Make Shift Filters

This falls into the something is better than nothing category. Running water through a t-shirt or other fabric will remove large particles and elaborate salvage-made systems may be minimally effective, but I wouldn’t rely on them unless I had no other option and it was a life or death situation.  

Final Thought…

While I know this information is intimidating, it is designed to help you understand the importance of properly purifying and filtering your water when in the wilderness or when traveling to areas that may not have modern water treatment procedures. In the next module, we will take a look at the different purification methods in greater detail.