Avoiding recreational water illnesses

Have a good backup plan

Unfortunately, not only are RWIs dramatically increasing, but research has also shown halogen disinfection creates hazardous byproducts. These disinfection byproducts (DBPs) include chloramines, trihalomethanes (THMs), haloacetic acids (HAAs), and other contaminates that are recognized to have serious negative health effects. It is also established that certain pathogens are resistant to chlorine and ozone, thus leading to various diseases including respiratory, skin, and gastrointestinal problems.

Awareness and concern about exposure to DBPs in pools and spas is increasing at an alarming rate. As a result, health officials have acknowledged the increase of RWIs and negative health effects associated to DBPs necessitates a paradigm shift in how pool and hot tub water is treated.

Experts agree, moving beyond the basics will require revising the two-pillar approach, which includes filtration and halogen, followed by adopting supplemental disinfection for water quality management (WQM).

Today’s three known and popular measures for the prevention of Crypto (and other RWIs for that matter) include the use of ultraviolet (UV) light, ozone, and enhanced filtration.

UV light

Inline UV disinfection is recognized as an extremely effective and reliable method for deactivating pathogens in the water and reducing the bathers’ exposure to DBPs. Many public health authorities are already beginning to mandate supplemental inline UV disinfection. For example, after the Crypto outbreaks in upstate New York a few years back, New York State now mandates this equipment on all public splash parks as do several other states and provinces, such as Ontario.

Ozone

Using ozone as a secondary oxidizer destroys ammonia and nitrogen, preventing the formation of chloramines. As a disinfectant, this technique requires a large unit to disinfect by injecting the ozone into a side stream (between 10 and 25 per cent of the water) and then returns it into the full flow. Ozone is capable of killing bacteria and Crypto cysts 3,125 times faster than chlorine.

Enhanced filtration

One viable and more affordable method that any facility or pool can begin using immediately is enhanced filtration. This technology uses two opposing biopolymers that quickly and effectively trap micro-organisms such as algae, Escherichia coli (E. coli), and Crypto.

This method of enhanced filtration has been soundly proven through an independent study conducted at Auburn University, which was presented at the World Aquatic Health Conference (WAHC) in 2005. The study showed very stable flocs of Crypto were able to form and be held in simulated sand filters. According to another presentation at the 2006 WAHC, there was a 99.9 per cent removal of Crypto from pool water using sand filtration treated using the two-stage polymer.

Giving swimming pool filters the ability to trap more debris is the idea behind enhanced filtration products. Using characteristics of naturally occurring biopolymers, which are widely used for clarification of pools as they showed a superior capacity to flocculate (or form larger clumps) and sediment suspensions of particles in water.

The pore paths in sand beds are typically 50 microns and up; therefore, the enhanced filtration products must generate clumps this large to be successful. Enabling filter media to remove particles that are in the submicron size allows for the removal of microbial organisms. The most troublesome RWIs measure a few microns (or smaller), and therefore, they typically pass through most filters with the flow of water.