Point-of-Entry Water Treatment for Small Communities in B.C.
Is it the Right Choice for Your Water System?Since the implementation of the B.C. Drinking Water Protection Act in 2001 and the accompanying regulations in 2003, small communities across the province have faced a wide range of challenges in meeting the requirements of the new legislation. In particular, many have struggled to get community support for conventional water treatment methods that would enable them to meet the water treatment requirements of the Act and Regulations.
The difficulty in obtaining community support for conventional treatment, largely due to the perceived negative aspects of chlorination, has led to considerable interest in point-of-entry treatment. At the same time, the emergence of new technologies that reduce maintenance frequency and improve compliance monitoring are making point-of-entry systems a viable option for many small communities; but, is point-of-entry treatment a good option for your community?
What is Point-of-entry (POE) Treatment?Simply stated, POE systems involve the installation of water treatment equipment on the main incoming water line in each and every home (and business) within the community as opposed to treating the water at a centralized location prior to distribution. POE systems treat all of the water entering the home, except in some cases, where water used exclusively for irrigation purposes is left untreated.
Point-of-entry treatment should be distinguished from point-of-use (POU) treatment which involves the treatment of water only at a single faucet or application.
Some Important POE Considerations
100 % Participation
In order to get approval for POE treatment, it is a requirement of the regional health authorities that 100% of the homeowners (and business owners, if applicable) connected to the system agree to the installation of the POE equipment in their homes. The larger a community is, the more difficult it is to achieve full participation. If just one connection does not agree, POE can be very difficult to implement as termination of a connection may be complicated by political, or even legal obligations. Most health authorities require that a letter of consent or similar document be signed by each and every home or business owner indicating their acceptance.
Ownership and Operation Requirements
While exceptions have been granted by certain health authorities, in the vast majority of applications, a key requirement of the health authorities is that POE systems are owned and operated by the water purveyor, not by the individual homeowners. This requirement is intend to ensure standardization of the equipment and that maintenance is undertaken as required by a qualified person. It is far easier and more practical for the health authority to oversee and regulate one water system owner than the many homeowners connected to that system. Accordingly, the water purveyor maintains responsibility for all of the POE systems. To execute its responsibilities for maintenance and monitoring on an ongoing basis, the purveyor needs to be able to access the equipment. This can be unpopular with homeowners and may be a barrier to obtaining community support for a POE project. Fortunately, POE system technology has come a long way, such that access is generally only required once or twice per year.
Depending on the form of governance of the water system, access rights can be entrenched by way of legal service agreements, strata bylaws, etc. In some cases, access rights have been secured by registering a right-of-way on the property titles for lots within the community. In any event, the water system will have to demonstrate to the relevant regulator that it has the authority to access the POE equipment for maintenance and monitoring as required, and that it has a policy with some effective consequences for homeowners that fail to comply (termination of water supply, etc.).
Provisions need to exist so that when a property changes hands, the new owners are made aware of, and are legally bound, by the same requirements as the departing homeowners.
B.C.'s health authorities require that water be treated to inactivate 99.99% of pathogenic viruses (4-log reduction). The choice of the specific target virus for this reduction goal has important implications for the choice of treatment equipment. Some of the health authorities use Rotavirus as their target, which can be inactivated to the required 99.99% level using a UV sterilizer validated to a minimum UV dose of 40 mJ/cm2. UV sterilizers that are validated to NSF/ANSI Standard 55 Class A are certified to meet this dosage requirement and are therefore the most common choice for point-of-entry systems. UV sterilizers that do not have this validation cannot generally be used in POE applications in B.C., although in rare instances, health authorities have granted exceptions (very rare!). It should be noted that UV sterilizers that are certified to NSF/ANSI Standard 55 Class B are NOT acceptable as they are only validated to a dose of 16 mJ/cm2 and they lack many of the important safety features found in Class A devices.
Some health authorities use Adenovirus as their target virus for 4-log inactivation. Adenovirus is much more resistant to UV disinfection and requires a dose of 186 mJ/cm2 for 99.99% inactivation. Affordable UV equipment validated to this UV dose is very limited, but available. As you might expect, it is considerably more expensive. Many health authorities that apply the Adenorvirus target allow for the use of NSF/ANSI Standard 55 Class A validated UV sterilizers in POE applications as a risk reduction strategy (while acknowledging that the 4-log virus reduction requirement is not fully met). This is most common in applications deemed to be at low risk of contamination from human waste. Such an exception is only granted at the health authority's discretion.
Generally speaking, POE treatments systems require less sophisticated operators as compared to centralized systems. While contractors can be hired to take care of all maintenance, it is possible for community volunteers to be trained in general maintenance tasks. This can reduce ongoing operating costs.
Where do you Start?Of course, before the selection of a treatment approach can begin, communities need to ensure that they have an effective governance structure in place, with representatives who are duly authorized to act on behalf of the community when negotiating with suppliers, applying for funding (if applicable), submitting applications for construction permits, and working on ongoing compliance issues with regulators. An effective governance structure provides confidence to regulators. Systems that have gained the confidence of regulators are more likely to be granted exemptions and exceptions that will keep costs down and generally make the permitting process smoother and faster.
Once governance is in place, it is imperative that the community begin to involve its citizens in the process of choosing a water treatment solution. Every opportunity should be taken to educate community members of the importance of meeting the requirements of the Act and Regulations and the options available to meet treatment obligations. Myths and misinformation should be quickly dispelled. Through positive education, a remarkable turn-around in the acceptance of the need for water treatment can be achieved even among those most opposed to any form of treatment. Involving community members will give them the opportunity to provide constructive input into the protection of their most valuable resource.
Similarly, establishing an open dialogue with health authority officials early in the process will create a co-operative framework that will positively influence the future approval of the community's preferred treatment option as well as the negotiation of installation and ongoing compliance monitoring requirements. Early involvement of the Drinking Water Officer from the local health authority will give you indications of their requirements and concerns about POE treatment as it would apply to your system so you are aware of potential obstacles that you will need to plan to overcome in your proposal.