Poisoned: 400 of Britain's lakes
Feb 11th 2007, 9:11 am
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Poisoned: 400 of Britain's lakes
http://news.independent.co.uk/environment/article2258886.ece
Poisoned: 400 of Britain's lakes
Many of our most famous waters, from the lochs to the Broads, are
being badly polluted. Environment Editor Geoffrey Lean reports
Published: 11 February 2007
Nearly 400 of Britain's most wildlife-rich lakes are being stifled by
pollution, an official study has found. They include most of the
country's best-known and best-loved expanses of water.
>From the Lake District to the Norfolk Broads, from Scotland's Loch
Lomond to Surrey's Frensham Great Pond, from wild Malham Tarn to
suburban Virginia Water, they are being devastated, mainly by sewage
and farming. Some, such as the haunting Semerwater in the Yorkshire
Dales, are so badly affected that they are virtually dead.
The study, headed by the Environment Agency, covered the 1,047 "most
ecologically valuable" of Britain's 14,000 lakes, those either
protected as Sites of Special Scientific Interest (SSSI), or home to
Britain's most endangered species.
It found that 379 of them are so "degraded" that they are in urgent
need of "rehabilitation". It is now joining with other official bodies
to mount a rescue programme of "lake habitat action plans".
"We all take lakes for granted," said Geoff Phillips, an Environment
Agency ecologist who led the study. "Nonetheless, many of them are
severely stressed as a result of human-induced pressures, to an extent
inevitable on a densely populated island."
Historically lakes have received less attention in clean-up campaigns
than rivers, but they are much more vulnerable because their more
stagnant waters allow pollution to collect and do more damage.
Mostly they are being fed to death by sewage and - especially - wastes
and fertilisers from agriculture. These cause weeds and algae to
flourish, soaking up oxygen from the water and suffocating other life.
And, partly as a result, they are often plagued by alien, invasive
species.
Bassenthwaite Lake, in the north of the Lake District, exemplifies
many of the problems. It is theoretically one of the most protected
water bodies in the country - being designated under the EU Habitats
Directive as an SSSI and as part of the Lake District National Park -
and is Britain's main stronghold of a very rare fish, the slim, blue-
green vendace. But it is still struggling to survive, despite efforts
to rescue it.
For decades, it was overfed by effluent from a local sewage works;
this has now been cleaned up, but phosphorous from the past pollution
still lurks in its sediments. And it is still being contaminated by
septic tanks used by houses around its shores.
More pollution comes from the droppings of the sheep that graze its
catchment. And allowing too many sheep on to the fells make things
worse; overgrazing erodes the soil, bringing it -and the wastes - down
into the lake.
Trees are now being planted to help to stabilise the soil, but the
waters produce blooms of blue-green algae, which can be toxic. And
they encourage an invasive species - the Australian swamp stonecrop,
originally introduced to Britain from Tasmania nearly 100 years ago -
which smothers other organisms.
Windermere, to the south, is struggling against another set of perils.
It, too, is polluted by sewage, augmented by a staggering six million
visitors a year. It also receives run-off from cattle farming. Last
year, its blue-green algal blooms were so bad that notices had to be
put up warning people, and their dogs, not to go into the water.
It, too, has a rare fish - the cold-water Arctic char - but as
pollution deprives the depths of the lake of oxygen in summer it is
forced to swim nearer the surface in waters too warm for it to
tolerate. Meanwhile, roach, an invasive species in this lake, flourish
in the balmier temperatures brought by global warming.
The bonny banks of Loch Lomond similarly wash pollution into the lake
from agriculture, and from fertilised golf courses - and it, too, is
polluted by sewage.
Right across the country, the growth of algae is so bad that it has
completely killed off underwater vegetation in many areas, which in
turn destroys invertebrate life and leads to changes in fish
populations. Some, such as Rollesby Broad and Cockshoot Broad, are
being restored, but still suffer from past pollution. Others, such as
Wroxham Broad, remain in deep trouble.
Surrey's Frensham Great Pond, tucked away in the Home Counties but
with an ecology closer to lakes in the northern uplands, receives too
many substances from earth disturbed by road building and other
developments in its catchment area. By contrast, Malham Tarn, high in
the Yorkshire Dales, has been damaged by nature lovers. A septic tank
in a field studies centre on its shores polluted it for years; it has
also been invaded by Canadian pondweed, probably brought on an
angler's rod or a hiker's boots.
Perhaps the saddest story of all is at Semerwater in Wensleydale -
which, by legend, covers a once-thriving city, cursed after turning
away a poor man seeking food. It, said Dr Stewart Clarke, an ecologist
at Natural England, has "suffered massive enrichment" from the dung of
the cattle raised around it. As a result, he said, "virtually no
submerged plants are left in Semerwater any more".
Norfolk Broads
Polluted by sewage. Phosphorous from sewage works remains in sediment
Frensham Great Pond, Surrey
Threatened by polluted soil disturbed by road building
Malham Tarn, Yorkshire Dales
Plagued by Canadian pondweed, probably introduced by anglers or hikers
Bassenthwaite Lake, Cumbria
Soil contaminated by sheep droppings has washed into the lake
Poisoned: 400 of Britain's lakes
Many of our most famous waters, from the lochs to the Broads, are
being badly polluted. Environment Editor Geoffrey Lean reports
Published: 11 February 2007
Nearly 400 of Britain's most wildlife-rich lakes are being stifled by
pollution, an official study has found. They include most of the
country's best-known and best-loved expanses of water.
>From the Lake District to the Norfolk Broads, from Scotland's Loch
Lomond to Surrey's Frensham Great Pond, from wild Malham Tarn to
suburban Virginia Water, they are being devastated, mainly by sewage
and farming. Some, such as the haunting Semerwater in the Yorkshire
Dales, are so badly affected that they are virtually dead.
The study, headed by the Environment Agency, covered the 1,047 "most
ecologically valuable" of Britain's 14,000 lakes, those either
protected as Sites of Special Scientific Interest (SSSI), or home to
Britain's most endangered species.
It found that 379 of them are so "degraded" that they are in urgent
need of "rehabilitation". It is now joining with other official bodies
to mount a rescue programme of "lake habitat action plans".
"We all take lakes for granted," said Geoff Phillips, an Environment
Agency ecologist who led the study. "Nonetheless, many of them are
severely stressed as a result of human-induced pressures, to an extent
inevitable on a densely populated island."
Historically lakes have received less attention in clean-up campaigns
than rivers, but they are much more vulnerable because their more
stagnant waters allow pollution to collect and do more damage.
Mostly they are being fed to death by sewage and - especially - wastes
and fertilisers from agriculture. These cause weeds and algae to
flourish, soaking up oxygen from the water and suffocating other life.
And, partly as a result, they are often plagued by alien, invasive
species.
Bassenthwaite Lake, in the north of the Lake District, exemplifies
many of the problems. It is theoretically one of the most protected
water bodies in the country - being designated under the EU Habitats
Directive as an SSSI and as part of the Lake District National Park -
and is Britain's main stronghold of a very rare fish, the slim, blue-
green vendace. But it is still struggling to survive, despite efforts
to rescue it.
For decades, it was overfed by effluent from a local sewage works;
this has now been cleaned up, but phosphorous from the past pollution
still lurks in its sediments. And it is still being contaminated by
septic tanks used by houses around its shores.
More pollution comes from the droppings of the sheep that graze its
catchment. And allowing too many sheep on to the fells make things
worse; overgrazing erodes the soil, bringing it -and the wastes - down
into the lake.
Trees are now being planted to help to stabilise the soil, but the
waters produce blooms of blue-green algae, which can be toxic. And
they encourage an invasive species - the Australian swamp stonecrop,
originally introduced to Britain from Tasmania nearly 100 years ago -
which smothers other organisms.
Windermere, to the south, is struggling against another set of perils.
It, too, is polluted by sewage, augmented by a staggering six million
visitors a year. It also receives run-off from cattle farming. Last
year, its blue-green algal blooms were so bad that notices had to be
put up warning people, and their dogs, not to go into the water.
It, too, has a rare fish - the cold-water Arctic char - but as
pollution deprives the depths of the lake of oxygen in summer it is
forced to swim nearer the surface in waters too warm for it to
tolerate. Meanwhile, roach, an invasive species in this lake, flourish
in the balmier temperatures brought by global warming.
The bonny banks of Loch Lomond similarly wash pollution into the lake
from agriculture, and from fertilised golf courses - and it, too, is
polluted by sewage.
Right across the country, the growth of algae is so bad that it has
completely killed off underwater vegetation in many areas, which in
turn destroys invertebrate life and leads to changes in fish
populations. Some, such as Rollesby Broad and Cockshoot Broad, are
being restored, but still suffer from past pollution. Others, such as
Wroxham Broad, remain in deep trouble.
Surrey's Frensham Great Pond, tucked away in the Home Counties but
with an ecology closer to lakes in the northern uplands, receives too
many substances from earth disturbed by road building and other
developments in its catchment area. By contrast, Malham Tarn, high in
the Yorkshire Dales, has been damaged by nature lovers. A septic tank
in a field studies centre on its shores polluted it for years; it has
also been invaded by Canadian pondweed, probably brought on an
angler's rod or a hiker's boots.
Perhaps the saddest story of all is at Semerwater in Wensleydale -
which, by legend, covers a once-thriving city, cursed after turning
away a poor man seeking food. It, said Dr Stewart Clarke, an ecologist
at Natural England, has "suffered massive enrichment" from the dung of
the cattle raised around it. As a result, he said, "virtually no
submerged plants are left in Semerwater any more".
Norfolk Broads
Polluted by sewage. Phosphorous from sewage works remains in sediment
Frensham Great Pond, Surrey
Threatened by polluted soil disturbed by road building
Malham Tarn, Yorkshire Dales
Plagued by Canadian pondweed, probably introduced by anglers or hikers
Bassenthwaite Lake, Cumbria
Soil contaminated by sheep droppings has washed into the lake
