THE environmental threats to the River Itchen, and potential solutions, were recently highlighted by a BBC Countryfile programme.

Whilst reporting on the controversy over food company Bakkavor's release of chemicals in the river at Alresford, the BBC also said that many farmers were acting on environmental concerns.

Another danger has been highlighted by a letter from a river keep and published in this week's Hampshire Chronicle.

Itchen threat

SIR: Anyone who watched Sunday’s BBC Countryfile report on the Itchen and other chalk streams of Hampshire will have been encouraged by the great work being undertaken to reduce pollution levels. It is especially heartening that some farmers have finally woken up to the harmful impact of their chemicals and other waste – and are doing something about it.

Unfortunately, there is another, darker side to the picture - plans by Eastleigh Borough Council to build thousands of houses on land that drains, via a network of feeder streams, directly into the River Itchen. If these plans ever go ahead, the damage would more than cancel out all the advances highlighted in the programme.

It is now recognised that excess fine sediment causes immense damage to chalk streams, as their relatively stable flows are unable to purge the sediment from the system. Many of the invertebrates that form the fundamental food web of chalk stream life are unable to cope with the accumulation of sediment, leaving behind an impoverished environment.

Particularly worrying is the effect that the building works would have on the trout and salmon that make it such an iconic river for anglers around the world. Their spawning sites are highly sensitive to any changes in the environment. Silt from the run-off would damage them beyond repair and possibly destroy them altogether. There would then be the open-ended problem of run-off that comes with any urban development.

The salmon and trout are just two examples of wildlife that would suffer under Eastleigh’s plans. I could also mention the otters, the rare Southern Damsel Fly and some nationally rare invertebrate species.

The programme rightly described the Itchen as one of the glories of our countryside. It is, however, far too soon to imagine that we have turned the corner in our efforts to protect it from human activity.

Chris Pearson Bsc, Msc,

Chairman,

Itchen Salmon Group and a River Itchen keeper