The precious life of an overgrown canal

When waterways are restored, boats must leave space for pond life. Christian Dymon reports

Save for the wooden posts of a disused jetty and the decaying hull of a canal boat now shrouded in reed sweet-grass, little alludes to the once thriving life of the Rednal Basin, a few miles from Oswestry in Shropshire.

In Victorian times this half-acre pool of water and its adjacent railway line exemplified the term "integrated transport system". Goods were loaded on and off boats waiting in the small basin and from there it was a 200- yard journey down an arm of the Montgomery Canal into the canal itself.

For the last few years the place has had a new life as a nature reserve, one of 17 which will eventually run along the 35 miles of the canal from Frankton Junction, where it meets the Llangollen Canal, through Welshpool to Newtown in Powys.

The creation of different sized nature reserves on the Montgomery Canal was agreed 10 years ago by British Waterways and the then Nature Conservancy Council.

It was one way of tackling a sensitive environmental issue which arises whenever canals with stretches that are designated Sites of Special Scientific Interest (SSSIs) are restored: what to do with the diversity of flora and fauna, often including rare species, that have taken hold in the waterway during its semi-derelict state?

The idea on the Montgomery Canal is that, by physically moving many species from the waterway into the "off-line" nature reserves located alongside it, submerged and floating aquatic plants which might otherwise be affected by large numbers of boats will at least be secured for posterity, although only time will tell how they adapt to their new environments.

Andrew Hearle, English Nature's conservation officer for Shropshire, says: "While you can physically move individual plants, there is no guarantee that the nature conservation interest for which a site was designated SSSI will be maintained in these newly created reserves. The whole aquatic ecosystem, the relationship of different plant and animal communities to each other, will have to be taken into account in any future designation."

Nearly half the length of the Montgomery Canal comprises three separate SSSIs. Various species of pondweed, including reddish pondweed, fennel pondweed, curled pondweed and small pondweed; floating water-plantain; yellow water-lily; frogbit; water-violet; greater duckweed; reed canary- grass; flowering rush; and certain scarce varieties of damselfly and dragonfly are found in a number of places.

"The pace of canal restoration is accelerating with more money available from the National Lottery, from Europe and from regeneration grants. The challenge is to restore canals for navigation at the same time as maintaining their nature conservation value," says Jonathan Briggs, a British Waterways conservation ecologist .

"Whether British Waterways would now adopt the Montgomery solution - which was agreed 10 years ago - for other canals is open to question," Mr Briggs adds. "These days we would be more sympathetic to a solution that enabled wildlife to survive in the main channel, even if it meant limiting the number of boats. This would also avoid the high cost of off- line reserves."

On Saturday, 21 September, in the canal's 200th anniversary year, a flotilla of vessels will herald the reopening, after 52 years, of a two-and-a-half- mile section of the Montgomery Canal in the West Midlands, stretching from Perry Aqueduct to Aston Locks.

Restoration has cost pounds 2.5m, money that has been channelled through Shropshire County Council from English Partnerships, the Government's regeneration agency. The new stretch will bring to 17 miles the total length which has so far been restored on both sides of the border. Rednal Basin, which had to be partially dredged in February this year because of a build-up of silt, lies just off the newly restored section, and so does another nature reserve at Aston Locks. Both are linked hydrologically to the canal, so ensuring a steady supply of suitable water.

Unlike Rednal, which already had some aquatic plant life and is part of an SSSI, the reserve at Aston Locks was created from a "green field" site by volunteers from the Inland Waterways Association's Waterway Recovery Group.

A water channel one-third of a mile long was dug out to take the transferred aquatic plants; on the dry areas there are alder, willow, oak, cherry and birch trees. So far the site has not been developed far enough to be designated an SSSI.

The two reserves have cost around pounds 100,000. In Wales, at what will be the biggest of the 17 Montgomery Canal reserves - the already SSSI-designated Guilsfield arm - more than pounds lm will eventually be spent, much of it on relining the arm of the canal and reinforcing the bank. At Welshpool a short section of new canal has been dug out for the use of boats, while the old channel has been left as an "on-line" reserve.

"The creation of these nature reserves is the first time anything like this has been attempted on this scale," says Andrew Law, district officer for the Countryside Council for Wales. "The intention is that when the reserves meet the appropriate criteria they will be designated as SSSIs."

Over on the other side of England, a different solution to a similar issue is being worked out. At the end of this month a draft report will be completed, after consultations between British Waterways and other bodies, concerning the future of the Pocklington Canal near York.

The nine-mile-long canal is navigable only from the River Derwent in the west to Melbourne, four miles to the east. Most of the canal comes within three SSSIs, two of which also form internationally important sites for migratory wildfowl.

"The intention is to draw up a 10-year management plan for the canal, and so avoid conflicts which might arise between different parties," says Keith Boswell, waterway manager for North Yorkshire Navigations.

"The management plan will look to retain the special nature conservation interest of the canal, and also consider what would be required to reopen the final five miles for navigation."