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Rain can turn sports pitches into mud baths. But embedding electrodes in the
pitch can help drain excess water away, say researchers from the University of
Newcastle upon Tyne. They sank a strip of wire mesh covered with plastic
sheeting half a metre into the soil of a pitch. They then embedded a second
strip of wire mesh above it, just beneath the grass. Applying a voltage between
the wire strips attracted positive ions dissolved in the water towards the
lower, negative electrode, drawing the water with them. Water at the lower
electrode then ran along the strip鈥檚 polymer coating to a drainage point at one
end, helping to dry out the waterlogged pitch.