Here are some of the best reader letters we have seen so far this week, you can join the discussion by commenting below.

•Long-term scheme for maintenance of rivers was never going to happen

Monday February 8

Duncan Mallett,

Horsey.

It's been interesting reading the correspondence regarding the state of the upper reaches of the River Wensum. Back in the 1970s and 80s my father (now 91 years young) was a contractor for Anglian Water. He held a couple of contracts with them and had responsibility to clean the Wensum twice each year, in June and again in September, and also the Deben down in Suffolk in the time between.

The Wensum contract originally stretched from Hellesdon Mill through Drayton, Taverham, Ringland, Lenwade, Swanton Morley, Billingford, North Elmham, Guist and Sennowe Park before terminating at Great Ryburgh but latterly was shortened from Swanton Morley to Great Ryburgh. The Deben section went from Woodbridge to Brandiston via Campsea Ash, Wickham Market and Easton. Dad also cut reed in the winter from January to May.

Dad had a team of four 'heavyweights' whose task it was to clear the Wensum of weed. Two of them would 'draw knives' back and forth across the river as they walked along and the other two would clear the banks of grass and thorn using scythes ahead of the 'drawers'.

The knives would be up to 20 scythe blades joined together with linkages with a rope on each end that the guys would pull back and forth (draw) as they walked. It was very hard physical work and not surprisingly two of Dad's team were members of Reedham Vikings tug of war team!

The knives would be drawn along the river bed and cut the weed which floated to the surface and then drifted downstream. Every mile or so Dad would construct a 'boom' with a rope tied across the river and branches laid on top to help catch the weed. Once a week or so the team, using long handled 'croombs', would pull all the weed from the boom and deposit it in the adjacent fields.

During the school holidays we (my brothers and I) would earn pocket money by 'helping' the gang. It's debatable how much help we were. Dad also used to clean several land springs and drains often for local landowners or the IDB (Internal Drainage Boards).

Every now and again we take dad for a drive and look at the rivers and drains and sadly there is very little, if any, maintenance at all. Rivers and drains are blocked.

I recall the Anglian Water plan in the late 1980s was to clear a six-metre swathe of trees and bushes on one side of all the rivers and drains to enable machinery to carry out the team's role, but it was never going to happen.

•Too cynical a view on space exploration

Tuesday February 9

Willliam Adcock

Blenheim Close, Long Stratton.

I am writing in response to the column by Steve Downes (EDP, January 30) regarding modern space exploration, which I found cynical to the point of being absurd.

Firstly he disparages modern space exploration, in particular space stations. If he had done his research he would have known that the space shuttle programme which so fired his schoolboy imagination, was instrumental in building the International Space Station (ISS) which he finds so boring. Furthermore, the space shuttle launches he watched on TV would have been very similar to the recent journey of Tim Peake to the ISS, ie short journeys (compared to the Apollo missions) orbiting the Earth with the astronauts doing 'sciency things'. I therefore think that his view that space missions weren't what they used to be when compared to the space shuttle missions is quite ridiculous.

Secondly I believe that the 'toe curling silences' during the interview with Tim Peake on board the ISS were more to do with the fact that they were interviewing someone travelling at 17,100mph, at a height of over 400km above the Earth's surface and with its resulting delay in transmission rather than 'question block'. Give them a break Steve! As a whole, I think the article smacks of a high degree of wilful ignorance and lack of basic research regarding the subject, but as Mr Downes himself admits; 'I always hated physics at school'.

•Investigation needed into wind farms

Wednesday February 10

Is it too simplistic to look at the sudden increase in the number of beached whales in Europe and in many incidences their close proximity to offshore wind farms and come to the conclusion that there might be a direct link?

All over the world studies are being carried out to assess the level of noise and vibration emissions from turbines, both during construction and operation to determine whether marine mammals' sensitive navigation and communication ability is being compromised.

There is real concern that the environmental impact has been grossly underestimated and we could be seeing tragic results.

Then you have to question if a truly independent investigation could possibly be carried out with so much money having been invested by both government and energy companies after being given the go ahead by the wildlife experts.

Increasingly the plummeting price of oil is making wind farms less viable, but hopefully the biggest losers won't turn out to be the wildlife that roam the seas.

•Government should do all it can to boost non-animal research

M Roberts

Valerian Rise, Thetford.

I am concerned about the continued use of animals in medical research and urge the government to invest more money into replacing animals in research. There were 3.87 million scientific procedures using animals in 2014 in the UK. Mice, rabbits, dogs, primates, cats and other animals are used in the safety-testing of new products, or in the development of new drugs and the study of human disease.

I believe that such animal experiments are both morally unacceptable and scientifically unsound. Animals are not laboratory tools. They are sentient beings, capable of experiencing pain, fear, loneliness, frustration and sadness. To imprison animals and deliberately inflict pain on them is morally indefensible. Animals make poor models of human disease. Because of the biological differences between species, the results from experiments on animals frequently prove to be misleading and unreliable when applied to humans. Cancer Research UK acknowledges: 'We do trials in people because animal models do not predict what will happen in humans.'

Ninety two per cent of new drugs that work well in animal studies go on to fail when they are first given to people in clinical trials.

A range of non-animal research methods already exists. Human-based methods such as the use of human cells, tissue and segments of DNA provide more reliable results than animal experiments because they apply to people and not animals. Other techniques include computer modelling, microdosing, the use of sophisticated scanners, and clinical and epidemiological studies.

I urge the government to do all it can to significantly increase funding for human-relevant non-animal research projects and to call for the use of such methods to replace animal experiments.

•Send your letters to The Letters Editor, EDP, Prospect House, Rouen Road, Norwich NR1 1RE. Email: EDPLetters@archant.co.uk

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