Effectiveness of Devices to Monitor Biofouling and Metals Deposition on Plumbing Materials Exposed to a Full-Scale Drinking Water Distribution System

Abstract

A Modified Robbins Device (MRD) was installed in a full-scale water distribution system to investigate biofouling and metal depositions on concrete, high-density polyethylene (HDPE) and stainless steel surfaces. Bulk water monitoring and a KIWA monitor (with glass media) were used to offline monitor biofilm development on pipe wall surfaces. Results indicated that adenosine triphosphate (ATP) and metal concentrations on coupons increased with time. However, bacterial diversities decreased. There was a positive correlation between increase of ATP and metal deposition on pipe surfaces of stainless steel and HDPE and no correlation was observed on concrete and glass surfaces. The shared bacterial diversity between bulk water and MRD was less than 20% and the diversity shared between the MRD and KIWA monitor was only 10%. The bacterial diversity on biofilm of plumbing material of MRD however, did not show a significant difference suggesting a lack of influence from plumbing material during early stage of biofilm development.

Metal Accumulation in Representative Plastic Drinking Water Plumbing Systems

“…No studies were found regarding heavy metals present in HDPE and PEX piping. A growing amount of evidence shows that plastic water distribution pipes can accumulate heavy metal scales (Figure 1) (Lytle et al, 2004;Cerrato et al, 2006;Campbell et al 2008;Friedman et al, 2010;Ginige et al, 2017), but no investigations were found that examined plastic building plumbing. In a survey of 15 U.S. water utilities, a wide range loadings of As (1,416 to 13,650 µg/g), Ca (4,455 to 57,790 µg/g), Fe (14,420 to 77,030 µg/g), and Pb (210 to 9,681 µg/g) were detected on PVC water distribution pipes (Lytle et al, 2004).…”

Testing Anti-Biofilm Polymeric Surfaces: Where to Start?

“…Ramage et al [140] employed an RO reactor to grow C. albicans on PMMA. Ginige et al [141] installed a modified RO reactor in a full-scale water distribution system to investigate biofouling on a high-density polyethylene surface.…”

Disinfection Processes

“…device was installed in a full-scale water distribution system to investigate biofouling and metal depositions on concrete, high-density polyethylene (HDPE) and stainless steel surfaces (Ginige et al, 2017). There was a positive correlation between increase of ATP and metal deposition on pipe surfaces of stainless steel and HDPE and no correlation was observed on concrete and glass surfaces.…”