Occurrence of trihalomethane in relation to treatment technologies and water quality under tropical conditions

Abstract

Distribution of most prevalent disinfection by-products, trihalomethanes (THMs) in relation to treatment technology and common water quality parameters (turbidity, conductivity, color, pH, and residual chlorine) was examined for two water supply schemes (WSS) in Sri Lanka (locations: Greater Kandy-WSS (GKWSS) (80.56–80.66 °E, 7.28–7.38 °N) and Kandy South-WSS (KSWSS) (80.49–80.63 °E, 7.21–7.30 °N). In both treatment plants, only CHCl3 and CHCl2Br were detected in appreciable concentrations and total THMs (TTHMs) values were well below the WHO limits (80 μg/L). TTHMs variations ranged from 0 to 16 μg/L and 0 to 54 μg/L in GKWSS and KSWSS, respectively. Highest TTHM value (54 μg/L) was found in KSWSS which employs pulsation treatment technology. Correlations between CHCl3 and CHCl2Br in both water schemes are noteworthy, but THM levels relate to most of the water quality parameters ambiguously. However, a distinct relationship is observed between THM levels and degree of chlorination, resident time, pipeline corrosion, and temperature. THM formation increased towards the boundaries of most of the sub-water supply schemes (SWSS).

Assessment of Water Quality in Chlorinated Drinking Water Distribution Networks Regarding to Trihalomethanes Formation

“…4, the THMs concentrations are conversely correlated to conductivity. Amaras Oriya et al [17] experienced strong negative correlations between conductivity and THMs concentration in different locations in Sri Lanka. It was also reported that conductivity plays an indirect role in THMs formation since one of the favourable precursors for THMs is hydrophobic NOM.…”

Disinfection Byproducts in Intermittent Piped Water Supplies

“…This is the only study to date that looked at the effects of intrusion and seasonality in IWS systems, and it provides a good start toward beginning to understand the effects of IWS dynamics. IWS systems are located in geographically diverse regions and cover major climatic ranges, – and many of these regions are also seeing significant watershed changes due to population growth, climate change, and other anthropogenic factors that affect water quality and quantity. , …”