Off flavours in large waterbodies: physics, chemistry and biology in synchrony.
The Laurentian Great Lakes of North America are a drinking water source for millions of Canadian and US consumers. These waterbodies have undergone extensive change over the past century as a result of widespread degradation and remediation. Many of the Lakes are prone to taste and odour (T&O), and although these outbreaks have been poorly monitored, evidence suggests that they are increasing in frequency. Tracing and controlling T&O in such large systems presents a challenging task, due to their physical size and complexity. This paper presents an overview of recent investigative and management approaches to T&O in Lake Ontario and its outflow, the St. Lawrence River. We have identified three distinct patterns of T&O in these source-waters, caused by geosmin and 2-methylisoborneol and differing in their planktonic and benthic sources, and temporal and spatial dynamics. Each pattern has required a different approach by scientists and management, in partnership with the water industry. We have shown these T&O outbreaks are caused and moderated by physical, chemical and biological mechanisms over a spectrum of spatial and temporal scales. Canadian municipalities affected by these outbreaks have been key to the investigation of the links between T&O and ecosystem processes with the aim to develop more proactive water treatment and long-term management.
Watson
S B
SB
Aquatic Ecosystems Management Research, Environment Canada, CCIW, Burlington, ON, Canada. Sue.Watson@ec.gc.ca
Charlton
M
M
Rao
Y R
YR
Howell
T
T
Ridal
J
J
Brownlee
B
B
Marvin
C
C
Millard
S
S
D001671:Biochemistry / Q000379:methods*; D002170:Canada; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005079:Excipients; D005618:Fresh Water; D045483:Rivers; D014481:United States; D014867:Water / Q000737:chemistry*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014876:Water Pollution; D014881:Water Supply
D005079:Excipients; D014874:Water Pollutants, Chemical; D014867:Water