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Elgin marvel

Flooding Flood alleviation

An end to Moray's centuries-old flooding problem is in sight, with alleviation proposals being submitted to the Council this month. Judith Cruickshank reports.

If you were choosing photographic locations for a 'Beautiful Scotland' calendar, Elgin would come high on the list of possibilities.

The view of the ruined cathedral seen from the far bank of the River Lossie, crossed by the graceful stone arches of the Brewery Bridge, must have featured on hundreds of tourist brochures, postcards and holiday snaps.

But if you wanted pictures of major urban flooding, Elgin would do just as well. Large areas of the town were inundated in the floods of November 2002. And that was just the latest in a series of events dating back hundreds of years.

Elgin is one of Scotland's oldest towns and has grown up along the banks of the Lossie over the past 900 years. Since the middle of the 18th century some 20 flood events have been recorded, 11 in the past 50 years. However, that does not necessarily mean that flood events are increasing in frequency. It is rather that the consequences of flooding are more severe and reporting more accurate.

'People now have cars, fitted carpets, more expensive furniture, TVs and stereo systems, ' says David Gowans, consultancy manager at Moray Council and project director of the flood alleviation group.

'Obviously, the consequences of your house being flooded are far more serious and much more expensive'.

The reorganisation of local government in Scotland meant that the aftermath of the 1997 flood event was being dealt with by a new council. Nor was only Elgin affected. Several other communities suffered from flooding at that time.

Rather than look for individual solutions, the council decided to seek a remedy that dealt with flooding throughout the county. Consultant Posford Haskoning was awarded a contract in November 2000.

The council's own engineers have been integrated with those from Posford Haskoning, forming a group with both local and specialist knowledge.

The team's first task was to evaluate the situation and produce a hydraulic model of the Lossie. The river drains an area of 270km 2and into it flow the Black Burn, the Tyrock Burn and the Mosstowie canal, all of which lie upstream of Elgin. The river winds through the centre of the town on its way to the sea at Lossiemouth.

Flooding is caused by extreme rainfall in the upper part of the catchment. Some water spills over the river channel banks on to the floodplain upstream of Elgin, reducing risk to the town.

But nonetheless, investigations demonstrate that on average the town is likely to be flooded one in every five years.

In November 2002 senior hydrologist Paul Hart had the somewhat doubtful pleasure of seeing the validity of his flood model tested to the full.

Some 160 properties and many businesses were affected when, once again, the Lossie overran its banks. The A96 was closed for several days and the Aberdeen to Inverness railway line was out of action for four weeks.

Average flow through the Lossie is around 5m 3/s. During the November floods it reached 147m 3/s.

As a consequence, 'the insurance on my house - which wasn't flooded and stands on high ground - went up by 30%', remarked one team member bitterly.

Hart at least had the consolation of seeing that his model was, in fact, extremely accurate, and the team could proceed with design of an alleviation system knowing that they were working from a sound base.

'We looked at hundreds of options, ' says Posford Haskoning group manager Steven Trewhella, and there were hundreds of meetings with local interest groups, farmers, landowners, and official bodies such as Historic Scotland. The task was made more complex by the group's objective of not simply protecting affected habitats and resources, but positively developing them whenever possible.

Three solutions emerged from the deliberations. These will be presented to Moray Council for a final decision at the end of this month. Details of all the proposals have already been on public exhibition, and comments and suggestions from the community were noted. There is also a system in the team office for logging details of all calls from members of the public in relation to the proposals. All this feedback has been taken into account when refining the details of the scheme.

The first proposal is for the construction of floodwalls and embankments along the river and reinstatement of parts of the floodplain. This would have the advantage of improving access to the river, but would mean that some businesses and properties would have to be relocated. The historic Brewery Bridge would be extended to accommodate the wider channel, as would other modern crossings, but one historic iron bridge would have to be replaced.

A second proposal is for flood storage, which would involve the construction of new dams, plus some flood defences in the town. There are already several large dams in Moray, so the concept is not new to the community and the council is experienced in dam maintenance.

The final option is for diversion of the water to the Spynie canal and thence to the sea.

Unfortunately, Trewhella says, the topography of the area - Elgin lies in a basin - would not allow construction of a new channel. Flood waters would be carried into the canal via three new tunnels and the canal allowed to overflow, resulting in permanent flooding of some areas.

The area drained by the Spynie canal was historically a loch which dwindled away as the result of a drainage scheme installed by none other than Thomas Telford. It is now low quality agricultural land.

Whatever the decision, the team is gearing up to produce a final design by late summer 2006. If there is no public inquiry, work could begin in 2006. Contractor AWG is already on board and mobilising for work on smaller schemes in the surrounding area.

Moving forward

Work on flood prevention measures in Lambride is due to start this spring. The village has suffered five flood events in 10 years, and the new scheme will involve the construction of walls and embankments plus storage which should protect the community from all but the most severe events.

Plans for Forres and Rafford are due to be presented for public consultation in March. The town is especially pretty, says Trewhella, and the team would wish to avoid walls and embankments along the Mosset Burn if possible. One factor here is Findhorn which boasts one of the highest gauged flows of any river in the UK and 'you wouldn't want to engineer that', he remarks.

Rothes was added to the list after the floods of 2002. This will be a particularly sensitive scheme to engineer as four steep narrow burns discharge into that most famous of salmon fishing rivers, the Spey, and, as is true of many towns in Moray, there are a number of distilleries producing Scotland's most famous export in the surrounding area.

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