Corrosion Control

Some water supplies require the use of corrosion control (CC) treatment to reduce water corrosivity to water mains and customer’s premise plumbing. Low pH or alkalinity and/or high chloride or conductivity are some of the characteristics of corrosive waters. Systems with CC treatment must monitor routine water quality (RWQ) parameters at least every two weeks at the distribution entry point and once per quarter at representative distribution sites. RWQ monitoring log sheets must be kept by the system and reported quarterly to NHDES upon trigger of either the lead (15 ppb) or copper (1.3 ppm) Action Level at the 90th percentile. Systems exceeding the Action Level must submit an Optimum Corrosion Control Treatment Report (OCCTR) within 6 months, implement the approved OCCTR within 1 year, and achieve two new compliant semi-annual LCR rounds within two years (system optimization) of the initial exceedance.

Corrosion Control Resources

• 90th Percentile Calculation (Wisconsin Department of Natural Resources).
• Optimal Corrosion Control Treatment Report (OCCTR) template.
• Routine Water Quality (RWQ) sample log sheet.
• EPA (2016) Optimum Corrosion Control Guidance.

Contact:
Cindy Klevens
cynthia.m.klevens@des.nh.gov
(603) 271-2948