Film sponsored by Northumbrian Water Authority to promote the activities of pollution monitoring at the Water Research Centre (WRC) in Northumberland.  Hidden away in a non-descript riverside shed is a high-tech water monitoring facility where live rainbow trout are used to detect changes in river pollution.  Views of a river. Close up of a liquid-transporting lorry on a motorway. A different tanker lorry pulls off the motorway onto a slip road. Close-up of the driver checking his mirrors,...

Film sponsored by Northumbrian Water Authority to promote the activities of pollution monitoring at the Water Research Centre (WRC) in Northumberland.  Hidden away in a non-descript riverside shed is a high-tech water monitoring facility where live rainbow trout are used to detect changes in river pollution.  Views of a river. Close up of a liquid-transporting lorry on a motorway. A different tanker lorry pulls off the motorway onto a slip road. Close-up of the driver checking his mirrors, then a view through the lorry’s back window as a car attempts to overtake. The lorry driver has to slam his brakes on as a car pulls out from round a corner. The vehicle behind the lorry crashes. Close-up of liquid leaking out on to the road. A yellow emergency service vehicle passes through a roundabout. Hazard clean-up workers connect hoses to the vehicle and work to swill away the spillage. Close-up of a blackberry. View of a drain and a stream. Close-up of water bubbling through a conduit into a river. The camera zooms in on a non-descript shed by the side of a river. Inside, the film reveals, is a high-tech pollution monitoring station. Banks of high-tech electronics fill the first room, and further back, behind curtained cubicles, are tanks of rainbow trout being tested with polluted water samples. Commentary: “For some time now, the use of trout as pollution monitors has been studied at Britain’s Water Research Centre”. A close-up of a trout’s head follows. Electrodes fixed to the side of the fish tank detect the trout’s sensitivity to pollution. Close-up of data being printed out. Views of a newly-developed panel electrode that offers better fish-monitoring performance being fitted into a tank of water. A scientist in a white coat adjusts a control knob on a signal amplifier. Gill movements and heart beats are monitored. Pollutants are poured into the fish tanks. Commentary: “The fish look serene enough, but already there were telltale differences in the readouts from their hearts and gills”. As more pollutants are poured into the tank, “the fish became highly distracted and swam aimlessly and violently, trying to escape”. Commentary: “At the slightest hint of pollution, alarms are raised, and water supplies to whole communities are automatically switched off”. Close-ups of fish swimming underwater. Commentary: "Today, fishy monitors are an added protection for society”.