Point-of-Use Arsenic Treatment
In the December issue Industry Insight Q&A on the 2006 arsenic rule, it is stated that new technology in centralized treatment has decreased the cost benefit of small communities utilizing point-of-use as a means of compliance. The Q&A goes on to state that only communities under 25 connections should consider point-of-use treatment as an option.
I believe it is critically important that more factual information be provided to the industry.
One example of real-world costs is from the 2005 AwwaRF project in Desert Sands, N. M. There, a utility with 475 service connections used a centralized GFH media system in order to meet the new arsenic standard. In the EPA report that was provided in March of 2005, it was stated that the water bill for the homeowners went from $24.50 a month up to $49.68—a $25.18 per month increase just for the arsenic treatment. This is for a large (475 connections) community. Conversely, a complete point-of-use implementation program would have amounted to well under $25 per month, closer to $12 per month.
Additionally, in Arizona it was recently reported that a water system is moving forward with the installation of a $20 million media-based arsenic treatment facility just outside Phoenix, not an uncommon cost analysis for a fairly large water system in the Southwest. Based on the cost for this arsenic treatment system and the population of the water system, however, the average water bill for these customers is anticipated to increase an astronomical 252%, going from $25 per month up to $88 per month.
There are numerous communities and private water systems from 10 up to more than 225 connections currently using point-of-use as a means of compliance. All of these communities have opted for the point-of-use program after looking at the costs associated with centralized treatment and making an informed decision that the point-of-use program is the most economical program in the end for them.
A side note: As mentioned in the Industry Insight Q&A, often these communities are extremely cost-conscious. Installing a centralized treatment system for arsenic now may get them into compliance for today; however, what about the water regulations coming down the line? Through point-of-use RO systems, these communities can not only be in compliance with the arsenic rule, but also address new water concerns such as perchlorate or endocrine disruptors at no additional cost. This is a fact that is often overlooked for these communities; however, it only adds to the long-term cost benefits of the point-of-use program.