- The Observer
12 25.08.19 News
Messing about with
the river: water fi rms
are draining Cam dry
Cambridge’s punting
idyl l is at r isk of bei ng
cut off at the source,
warn campaigners
It’s a beautiful day on the river Cam
in Cambridge. As the sun sparkles on
the water at Jesus Green lock, tourists
line up for ice-cream and prepare to
take a punt around the university’s
most celebrated colleges. Few notice
how pathetic the fl ow of water is over
the lock.
It is a clear sign that this ancient
waterway is faring badly, says
Stephen Tomkins , emeritus fellow
and former head of the science fac-
ulty at Homerton College. “That lit-
tle bit running through here is the
total fl ow from the whole of south
Cambridgeshire,” he says, pointing at
an unimpressive trickle. There just is
not enough water, he adds: “The river
Cam is drying up.”
Tomkins chairs the Cam Valley
Forum environmental group, which
earlier this month sounded the alarm
about the Cam with a manifesto that
warns that the river can no longer
function properly.
“It is just not just ‘the weather’,” the
manifesto states. “Over-abstraction
of water from the ground is the main
reason. We pump too much water
out of the chalk for our domestic
supplies and, to a smaller extent, for
agriculture.”
A report by the EnvironmentAgency last month also revealed the
river’s fl ow is now exceptionally low,
just 33% of its long-term average.
The chalk streams that feed the
Cam with crystal-clear groundwater,
fi ltered naturally by the local chalk
hills, are dying beca use of this over-
abstraction, says Tomkins. In total,
65% of the groundwater is pumped
out of the chalk for drinking water
supplies – and a further 20% is used
for augmentation by the water com-
panies to “disguise the problem”.
“They have to put water back into
the headwaters of the streams in the
summer to keep those streams run-
ning, because they have taken so
much water out of the chalk,” he says.
This manoeuvre hides how low
the water table has sunk, says Ruth
Hawksley , a Wildlife Trust offi cer in
Cambridgeshire. “If they didn’t pumpDonna Ferguson