If you live in Sandy, chances are you received a notice in your last water bill. The technical terms were that the city had exceeded the standard "DBPR HAA5 MCL" levels allowed in potable water as spelled out by the state.
So what, exactly, is HAA5? The byproduct of chlorine reacts with organic matter found in water sources, such as reservoirs. It's also a fairly new issue in Sandy.
"This has only been an issue since we've been using the city of Portland's water," Sandy Public Works Director Mike Walker explained.
Sandy started utilizing the Portland Water Bureau's Bull Run source in 2014 to supply water to its growing population. The HAA5 — or haleoacetic acid compounds — occur because of the proximity of where Sandy's line connects with Portland's, close to where Portland adds its chlorine disinfectant to the water.
The higher concentration leads to the reaction in the water and thus the byproducts the city is warning of now.
"It's hard to say if it's in everybody's water, since some people get a blend of water and some don't get any Portland water," Walker added. Sandy has two of its own water sources that serve residents throughout the city.
When an issue such as exceeded standards of a particular compound or element arises, the city must notify its customers.
There is a very minimal health risk related to drinking water that contains HAA5. However, the notice states that "People who drink water (one liter per day for 70 years) containing haleoacetic acids in excess of the MCL over many years have an increased risk of getting cancer."
"Any adverse health impacts would accumulate over several years," Walker added. "The health effects don't accumulate overnight."
In response to the issue, the city of Sandy is investigating filtration options, and has signed a compliance agreement with the state Drinking Water Program to make improving the city's current system a mandatory project to be completed by December 2018.