Water quality is improving along the River Aire, boosting fish stocks and attracting more wildlife. HELEN MEAD looks at the work being done to make the river an attractive resource for anglers and other local people.

Five years ago, a salmon was caught on rod and line in the River Aire at Eggborough near Selby.

The catch made headline news, for it was many years since salmon had graced the waters of the river.

Historically, the Aire was a salmon river with catches recorded into the early part of the 19th century until the effects of pollution resulted in them dying out.

In recent years salmon have returned to the lower reaches of the river - a sign that the river is becoming cleaner.

"There are signs of salmon returning to the lower stretches of the Aire, but there are still access problems to be overcome," says Richard Atkinson, recreation and technical officer with the Environment Agency, which last year announced a five-year action plan to make further environmental improvements on the river.

"When water quality improves the fish population changes, and we are seeing more trout further upstream. Populations of grayling are improving, especially around Skipton, and some juvenile fish have been caught showing that they have bred naturally. It is very, very encouraging to see."

Major improvements made by Yorkshire Water to the quality of effluent, or waste, released from Marley, Esholt and Knostropp sewage treatment works has had a great impact upon water quality.

Coupled with restocking programmes by the Environment Agency, this has seen the fish population rise dramatically, and led to coarse fish populations being re-established in areas that were once unable to support them.

Despite these improvements, there is no room for complacency, and further work is ongoing to create a sustainable, healthy fish population for the future.

One of the main barriers to fish migration are the weirs - a legacy of the area's industrial past. The River Aire has more than 30 major weirs due to past industrial milling practises and improvements in navigation. They occur at intervals from its upper headwaters near Malham in the Yorkshire Dales to Chapel Haddlesey near Selby.

"The weirs form large obstructions, primarily in the lower to middle sections of the Aire," says Mr Atkinson.

"They present barriers to moving upstream, so the fish cannot reach their spawning sites."

The agency wants to construct special passes for fish to swim through. Work on each weir will be costly and is dependent upon funding.

In June this year the agency announced that it had obtained a £309,000 Heritage Lottery Fund award for waterfront regeneration works including a fish pass on the weir at Castleford.

In addition, the agency is working in partnership with riverside developers to help improve access for fish over the weirs. One of these will allow fish to negotiate the weir at Ireland Bridge in Bingley.

And at Hirst Wood weir near Saltaire, the agency worked in partnership to incorporate a notch in the weir. This will reduce the height for fish to ascend it.

In spite of the initial cost of the fish passes it will, the agency believes, be more economical in the long-term for the fish to move around freely than to keep re-stocking the river.

Officers from the agency carry out annual surveys, noting changes in the fish population - numbers and species. They also speak regularly to anglers. "They feed their observations back to us, about what they would like to see and which parts of the river they feel should be restocked," says Mr Atkinson.

In the past five years £60,000-worth of dace and chub have been stocked in the Aire between Skipton and Bradford. This phased restocking has taken place recently due to the improvements in water quality, which has reached a standard seen as suitable to ensure their long-term survival."

"We are continuing to stock to boost fish populations - the next programme will take place this year or next."

From the headwaters of the river down to Gargrave, the river is home to brown trout, with growing numbers of grayling.

Below Gargrave the fishery continues to be predominantly trout with increasing numbers of chub, dace, pike and roach.

The distribution of trout and grayling is beginning to extend further downstream into the Bradford and Leeds districts, which are still predominantly supporting a healthy coarse fish population.

"With the water being cleaner we are seeing sustainable populations of fish - we have got brown trout in the middle of Bingley," says Mr Atkinson.

"We used to stock them in the tributaries where the water is cleaner, but lately they have dropped out of the nursery areas into the main river, which is an indication of cleanliness. There is a healthy trout population around Saltaire, and a large trout weighing between 8lb and 9lb was caught at Thwaites Mill below Leeds."

As the fish population has increased, so has the number of otters. "Otters have been spotted on tributaries and on the main river," says Mr Atkinson. The river system provides an essential travelling, feeding and breeding corridor, and the Environment Agency, working with partners including Bradford Council and Yorkshire Water, works to ensure that no obstructions appear along the river banks through new developments.

Further improvements to sewage treatment works are in the pipeline, with Yorkshire Water's pledge to spend £110 million over the next five years, with the bulk being spent at Esholt and Knostrop works.

And it is hoped that in the future, improvement works can be carried out in partnership with landowners along the Upper Aire nears Skipton as part of the Environmental Stewardship Scheme. "The aim would be to improve the river and river banks where it has been badly degraded in the past," says Mr Atkinson.

"There is a big emphasis on working in partnership, not just with larger organisations such as Bradford Council, but with local people - community groups."

"The improvement in water quality will benefit everybody, not only anglers but people who enjoy water-based activities on the river."

Peter Britton, wildlife officer for Bradford Council's Countryside Service, is pleased with the progress made so far.

"The water quality is slowly improving. This can be seen fairly easily by the indicator species such as greyling moving further downstream."

He adds that the movement of fish is not the only indicator of cleaner waters. "We are seeing a lot more bird life on the river than we have seen previously. We are seeing a lot more sawbills - fish-eating birds - which suggests that we are having better hatches of spawned fish."

"We are working very hard and getting co-operation from a lot of other agencies, individuals and other groups in the Aire Valley. I am particularly pleased with how it is progressing. It is a steady improvement, but there is still a long way to go."