Let's take another trip on the Oregon Trail. We'll make sure to carry some clean water so that dysentery isn't a problem for us. Actually, today we'll talk about some more recent events...Woodstock 1999.
Human Event
What happened at Woodstock 1999? Promoters who were wishing to relive the successes of other Woodstock events that took place in 1969 and 1994 scheduled another huge 4-day music festival for the summer of 1999. I know, stay with me, this doesn't yet seem to have anything to do with safe drinking water. Let me attempt to make the connections.
Check out the following before and after pictures of the venue, which by the way was held at an old abandoned air force base in Rome, NY.
We can use this picture as a before and after of a water bacterial contamination event. If water is not properly treated and monitored for the effectiveness of the treatment, the before and after of the event can be illustrated by the feeling you get from these two pictures. At one point, everything is clean, pristine, and safe. Following contamination, it seems, disaster has occurred.
What events happened in between the taking of the two pictures? Well, in case of Woodstock 1999, thousands of drunk and probably high young adults and teenagers gathered and ran wild while listening to loud music. As things progressed through the days of the festival, some of these drunk and high concert goers became violent and destructive.
Here's a picture of the crowd before the "infection" became out of control.
That is a heck of crowd. Not my comfort zone, but masses of people don't always mean trouble. Next, take a look at a picture of the final night of the concert.
Just prior to the crowd starting fires and rioting, promoters of the event decided that giving everyone in the crowd lighted candles would cause a nice Kumbaya moment, but this was the end of the '90s not the end of the '60s. Young people were not the same; culture was not the same; and the Red Hot Chili Peppers were playing a cover of the Doors' "Light My Fire".
What...........................What...................What? You don't get what any of this story has to do with water monitoring?
Treatment Event
Think about that clean concert venue in the first picture that you saw and picture a security camera watching that area the whole time the concerts are going on. Think of the event space as the water that you receive from your water utility. Next think of the concert attendees as the bacteria that might be present in the water coming out of your faucet. Not all of the concert goers participated in violence or destruction, but some did. Think of the security camera that is filming the whole event as a testing procedure for a potential future problem
Please forgive me if the analogy gets a little weak here.
The City of Leon is looking to continually have a clean field when it comes to the water that it delivers to its customers. In order to insure that is the case, we test water from different locations spread throughout the city. We are required to test 2 locations per month for total coliform bacteria. The test locations move to different sections of town each month. You can think of total coliform as the whole crowd of people. Not every individual in the crowd is up to no good, but some could be. If there is not a crowd of people, then there isn't anyone present to cause trouble. So, each test is like a snapshot taken from the security camera. Each time we want to see an empty field.
If a sample is positive for total coliform bacteria, then more testing is required to see if there are "bad guys" in the crowd. Follow up samples can be tested for bacteria that will cause disease by testing for E. Coli. E Coli is one of the bad guys that can hide in the crowd and cause illness. If E. Coli is present immediate action must be taken so that people are safe.
Why don't we test for E. Coli straight away? The test for total coliform bacteria is simple, quick, and cheap, and since E. Coli is a subset of coliform bacteria, if no coliform bacteria are present, then there isn't any E. Coli either.
Disaster Insurance
The mechanism of action that is used to ensure that waterborne illness does not break out in our community is a simple chemical compound, bleach. Bleach is a chlorine compound, and chlorine has been used for many decades to disinfect water supplies. This disinfection has basically eradicated waterborne disease in developed countries.
The US EPA requires that all water supplies using surface water (lakes and rivers) as a water source to calculate, on a daily basis, the effectiveness of the disinfection. This calculation uses known factors for killing difficult to kill organisms that may be present in the water source to ensure that the disinfection is sufficient.
Giardia is a parasitic organism that can be present in rivers and lakes. Giardia is a more complex organism than viruses or bacteria. In addition, it forms a protective cyst around itself in one stage of its life cycle. This cyst means that a greater amount of disinfection is required to prevent water from causing human infection from them. The "amount" of disinfection that is required to inactivate 99.9% of Giardia cysts is 12 times higher than the "amount" of disinfection required to inactivate 99.99% of viruses. Inactivation for bacteria is somewhere in between viruses and Giardia. Therefore, if the standard is met to inactivate the Giardia, the bacteria and viruses will have been inactivated also.
So, hear me now and believe me later. Each and every day water departments across the country are in the business of preventing disease and providing for human flourishing. Each and every business that you enter is likely to have at least a bathroom with a toilet and sink providing for a clean source of water and convenient disposal of waste. What else provides for more economic development opportunity than these two services?