Heatwave turns America's waterways into rivers of death

Falling water levels are killing fish and harming exports

A A A

The cruel summer heat-wave that continues to scorch agricultural crops across much of the United States and which is prompting comparisons with the severe droughts of the 1930s and 1950s is also leading to record-breaking water temperatures in rivers and streams, including the Mississippi, as well as fast-falling navigation levels.

While in the northern reaches of the Mississippi, near Moline in Illinois, the temperature touched 90 degrees last week – warmer than the Gulf of Mexico around the Florida Keys – towards the river's southern reaches the US Army Corps of Engineers is dredging around the clock to try to keep barges from grounding as water levels dive.

For scientists the impact of a long, hot summer that has plunged more than two-thirds of the country into drought conditions – sometimes extreme – has been particularly striking in the Great Lakes. According to the Great Lakes Environmental Research Laboratory, all are experiencing unusual spikes in water temperature this year. It is especially the case for Lake Superior, the northernmost, the deepest, and therefore the coolest.

"It's pretty safe to say that what we're seeing here is the warmest that we've seen in Lake Superior in a century," said Jay Austin, a professor at the University of Minnesota at Duluth. The average temperature recorded for the lake last week was 68F (20C). That compares with 56F (13C) at this time last year.

It is a boon to shoreline residents who are finding normally chilly waters suddenly inviting for a dip. But the warming of the rivers, in particular, is taking a harsh toll on fish, which are dying in increasingly large numbers. Significant tolls of fresh-water species, from pike to trout, have been reported, most frequently in the Midwest.

"Most problems occur in ponds that are not deep enough for fish to retreat to cooler and more oxygen-rich water," said Jake Allman of the Missouri Department of Conservation. "Hot water holds less oxygen than cool water. Shallow ponds get warmer than deeper ponds, and with little rain, area ponds are becoming shallower by the day. Evaporation rates are up to 11 inches per month in these conditions."

In some instances, fish are simply left high and dry as rivers dry up entirely. It is the case of the normally rushing River Platte which has simply petered out over a 100-mile stretch in Nebraska, large parts of which are now federal disaster areas contending with so-called "exceptional drought" conditions.

"This is the worst I've ever seen it, and I've been on the river since I was a pup," Dan Kneifel, owner of Geno's Bait and Tackle Shop, told TheOmahaChannel.com. "The river was full of fish, and to see them all die is a travesty."

As water levels in the Mississippi ebb, so barge operators are forced to offload cargo to keep their vessels moving. About 60 per cent of exported US corn is conveyed by the Mississippi, which is now 12ft below normal levels in some stretches. Navigation on the Mississippi has not been so severely threatened since the 1988 drought in the US. Few forget, meanwhile, that last summer towns up and down the Mississippi were battling flooding.

One welcome side-effect, however, is data showing that the so-called "dead zone" in the Gulf of Mexico around the Mississippi estuary is far less extensive this summer because the lack of rain and the slow running of the water has led to much less nitrate being washed off farmland and into the system than in normal years. The phenomenon occurs because the nitrates feed blooms of algae in Gulf waters which then decompose, stripping the water of oxygen.

Arts & Entertainment
Schwarzenegger winning Mr. Universe 1969
arts + entsCan you guess the celebrity from these British Pathe News clips?
Sport
Raheem Sterling and Luis Suarez celebrate during Liverpool's game with Norwich
football Another hurdle is out of the way for Brendan Rodgers' side
News
Portrait of Queen Elizabeth-II by David Bailey which has been released to mark her 88th birthday
peoplePortrait released to mark monarch's 88th birthday
Life & Style
The writer, Gerda Saunders, with her mother, who also suffered with dementia before her death
healthGerda Saunders on the most formidable effect of her dementia
VIDEO
Have you tried new the Independent Digital Edition iPad app?
Sport
Manchester United manager David Moyes looks on during his side's defeat to Everton
footballBaines and Mirallas score against United as Everton keep alive hopes of a top-four finish
Arts & Entertainment
Jessica Brown Findlay as Mary Yellan in ‘Jamaica Inn’
TVJessica Brown Findlay on playing the spirited heroine of Jamaica Inn
News
YouTube clocks up more than a billion users a month
mediaEuropean rival Dailymotion certainly thinks so
Arts & Entertainment
The original design with Charles' face clearly visible, which is on display around the capital
arts + ents The ad shows Prince Charles attired for his coronation in a crown and fur mantle with his mouth covered by a criss-cross of white duct tape
Arts & Entertainment
‘Self-Portrait Worshipping Christ’ (c943-57) by St Dunstan
books How British artists perfected the art of the self-portrait
Sport
Luis Suarez celebrates after scoring in Liverpool's 3-2 win over Norwich
Football Vine shows Suarez writhing in pain before launching counter attack
News
People White House officials refuse to make comment on 275,000 signatures that want Justin Bieber's US visa revoked
News
Sir Cliff Richard is to release his hundredth album at age 72
PEOPLE
Sport
Lukas Podolski celebrates one of his two goals in Arsenal's win over Hull
football
Arts & Entertainment
Quentin Tarantino, director
film
News
The speeding train nearly hit this US politican during a lecture on rail safety
news As the saying goes, you have to practice what you preach
Sport
Mercedes Formula One driver Lewis Hamilton of Britain (front) drives ahead of Red Bull Formula One driver Daniel Ricciardo of Australia during the Chinese F1 Grand Prix at the Shanghai International circuit
sport
Arts & Entertainment
Billie Jean King, who won the women’s Wimbledon title in 1967, when the first colour pictures were broadcast
tv
News
Snow has no plans to step back or reduce his workload
mediaIt's 25 years since Jon Snow first presented Channel 4 News, and his drive shows no sign of diminishing
Life & Style
food + drinkWhat’s not to like?
Have you tried new the Independent Digital Edition iPad app?
iJobs Job Widget
iJobs General

Geography Teacher

£130 - £140 per day: Randstad Education Ilford: Secondary Geography Teacher Lo...

Do you want to work in Education?

£55 - £70 per day: Randstad Education Cheshire: Are you a dynamic and energeti...

SEN Teaching Assistant

Negotiable: Randstad Education Group: SEN TAs, LSAs and Support Workers needed...

Private Client Senior Manager - Sheffield

£50000 - £60000 per annum: Pro-Recruitment Group: The Sheffield office of this...

Day In a Page

How I brokered a peace deal with Robert Mugabe: Roy Agyemang reveals the delicate diplomacy needed to get Zimbabwe’s President to sit down with the BBC

How I brokered a peace deal with Robert Mugabe

Roy Agyemang reveals the delicate diplomacy needed to get Zimbabwe’s President to sit down with the BBC
Video of British Muslims dancing to Pharrell Williams's hit Happy attacked as 'sinful'

British Muslims's Happy video attacked as 'sinful'

The four-minute clip by Honesty Policy has had more than 300,000 hits on YouTube
Church of England-raised Michael Williams describes the unexpected joys in learning about his family's Jewish faith

Michael Williams: Do as I do, not as I pray

Church of England-raised Williams describes the unexpected joys in learning about his family's Jewish faith
A History of the First World War in 100 moments: A visit to the Front Line by the Prime Minister's wife

A History of the First World War in 100 moments

A visit to the Front Line by the Prime Minister's wife
Comedian Jenny Collier: 'Sexism I experienced on stand-up circuit should be extinct'

Jenny Collier: 'Sexism on stand-up circuit should be extinct'

The comedian's appearance at a show on the eve of International Women's Day was cancelled because they had "too many women" on the bill
Cannes Film Festival: Ken Loach and Mike Leigh to fight it out for the Palme d'Or

Cannes Film Festival

Ken Loach and Mike Leigh to fight it out for the Palme d'Or
The concept album makes surprise top ten return with neolithic opus from Jethro Tull's Ian Anderson

The concept album makes surprise top ten return

Neolithic opus from Jethro Tull's Ian Anderson is unexpected success
Lichen is the surprise new ingredient on fine-dining menus, thanks to our love of Scandinavian and Indian cuisines

Lichen is surprise new ingredient on fine-dining menus

Emily Jupp discovers how it can give a unique, smoky flavour to our cooking
10 best baking books

10 best baking books

Planning a spot of baking this bank holiday weekend? From old favourites to new releases, here’s ten cookbooks for you
Jury still out on Manchester City boss Manuel Pellegrini

Jury still out on Pellegrini

Draw with Sunderland raises questions over Manchester City manager's ability to motivate and unify his players
Ben Stokes: 'Punching lockers isn't way forward'

Ben Stokes: 'Punching lockers isn't way forward'

The all-rounder has been hailed as future star after Ashes debut but incident in Caribbean added to doubts about discipline. Jon Culley meets a man looking to control his emotions
Mark Johnston: First £1 million jackpot spurs him on

Mark Johnston: First £1 million jackpot spurs him on

The most prize money ever at an All-Weather race day is up for grabs at Lingfield on Friday, and the record-breaking trainer tells Jon Freeman how times have changed
Ricky Gervais: 'People are waiting for me to fail. If you think it's awful, then just don't watch it'

Ricky Gervais: 'People are waiting for me to fail'

As the second series of his divisive sitcom 'Derek' hits screens, the comedian tells James Rampton why he'll never bow to the critics who habitually circle his work
Mad Men series 7, TV review: The suits are still sharp, but Don Draper has lost his edge

Mad Men returns for a final fling

The suits are still sharp, but Don Draper has lost his edge
Google finds a lift into space will never get off the ground as there is no material strong enough for a cable from Earth into orbit

Google finds a lift into space will never get off the ground

Technology giant’s scientists say there is no material strong enough for a cable from Earth into orbit