Water Treatment - Some Comparisons

The Society occasionally gets questions about why we're using the water treatment system we do and why some other system might not be better or cheaper. In this post, I'm going to try and briefly outline the various options and how they compare.

It's first necessary to say that NOT treating our water is NOT an option. This would place our community under an immediate boil water order and expose residents and visitors to the risk of illness from water-borne pathogens and parasites. Kootenay Lake water might have been safe to drink untreated in the past, but it's not safe now. In fact, no surface water source can be assumed to be safe and when you're providing water to a community, you can't take the chance. Furthermore, as a water supplier, the Society is required by Provincial legislation to provide safe water. The required goal is something called the 43210 standard - more on that in another post. Treatment, in one form or another, is the only way to get those results.

There are essentially 2 treatment strategies: 1) centralized treatment, and 2) POE/POU treatment.

Centralized treatment is what our system uses now. All water pumped from the lake passes through this system and is stored in a reservoir for distribution. The big disadvantage to centralized treatment is that ALL water goes through this system, including water that is only being used to water the garden, wash the car and such. There is no easy or cheap solution to that problem. Our system uses filtration to 1 micron and chlorination. This is a process which has been proven safe, effective and cheap. There are other possible treatment processes, including UV, sand filters, charcoal beds and so on, but some of these are more suitable to larger municipal systems which are using large volumes of water. One concern with chlorination is the chlorine and chlorine byproducts remaining in the water we drink. Given the number of people world wide that also have chlorine in their water, this wouldn't seem to be an unknown problem, but if people have concerns, it can be dealt with at the tap with simple and cheap filters.

One additional advantage to using chlorine is that it protects against bacterial and fungal growth while the water is stored, for example, while it is sitting in a reservoir. This is a benefit that water treated with UV does not have.

From our standpoint, our centralized treatment system meets provincial quality standards, it's effective (we don't get bacteria in our water), it's cheap to operate (only a couple of hundred $$ each year), and that to fix or change anything we only have to go to ONE location, not each house on the system.

POE/POU stands for Point of Entry (where all water is treated as it enters each house) and Point of Use (where a filter might be attached to the cold water tap in the kitchen, for example). POE systems might include filtration (provincial regulations require filtration to 1 micron), UV, or some other process. POU systems generally would use some kind of filter at a specific tap but could also use reverse osmosis or distillation.

A community planning to use a POE system would need to have 100% of the residents approving and agreeing to use this system. There would need to be equipment installed at each house, the Water Society would need regular access to that equipment to service it and the equipment would be owned by the Society. The cost would depend on what process was used, but could be anywhere from $500 to several thousand $$ per house. Instead of having one service location, there would be 26 (with our community's size) and even if each system cost only $500, we'd be looking at $13,000 to install a system like this.

POU systems can be installed by anyone on any tap they want. Consumers could also have their own distillation or reverse osmosis system. Such systems alone would not be approved by Interior Health for a community water supply.

The bottom line for us is that we have a system that is working now, requires little maintenance to operate and is cheap and effective.