Evaluation of corrosion control products on a distribution system through crowdsourcing.

Crowdsourcing of citizens was used to determine the effectiveness of corrosion control in a water distribution system. This study examines the frequency and severity of "Red Water" complaints over a period of 4 years, and two different corrosion control chemicals, polyphosphate and zinc orthophosphate. The data revealed that the frequency of Red Water complaints was higher when using zinc orthophosphate while the severity (higher iron) was higher when using polyphosphates. Varying the dose of zinc orthophosphate to account for cold months induced a greater number of customer complaints. Moreover, corrosion coupons studies suggest similar performance of both corrosion inhibitor products. The corrosion and complaints might be driven by microbial-induced processes in which diatoms might play a significant role.