Only 'catastrophic' rainfall could flood Upper Lough Erne - Finance Minister in 1950s

Chris Donegan • Published 26 Nov 2009 09:00 Comments 1 Comment

See also:

The water level on Lough Erne is "controlled" by three sets of sluices - on the River Erne at Enniskillen, Cliff hydro-electric dam downstream of Belleek and Kathleen's Falls hydro-electric dam at Ballyshannon.

The system was designed in the 1950s to allow at least 660,000 cubic feet of water to flow out of the Erne into the sea every minute. The aim was to be able to drain off the water as quickly as possible to prevent flooding.

The Northern Ireland Minister of Finance at time, Major Maynard Sinclair declared: "The Upper Lough, around which the flooding is most acute, should never again, unless the rainfall is catastrophic, reach the levels of 157 to 159 feet above(sea level at Ballyshannon) to which the waters have frequently risen in the past; levels which give rise to the widespread flooding the present proposals seek to prevent.

Under the cross-Border deal, known as the Erne Drainage and Development Act, the Stormont and Dublin governments agreed limits on how high and low the water should be allowed to go.

The sluices at Portora, just downstream of Enniskillen, were completed in 1955. They control the level of the Upper Lough and are operated by the Rivers Agency in Northern Ireland. At times of low water they are lowered to create a dam to ensure the level at that point does not fall below 150 feet above sea level so the lake can still be navigated by boat.

The sluices at Cliff and Kathleen's Falls control the level of Lower Lough Erne and are operated by the Electricity Supply Board in the Republic of Ireland.

The levels are maintained within statutory limits. The Lower Lough is not allowed to rise above 152 feet above sea level nor fall below 147 feet. The Upper Lough, as far as "reasonably preventable" is not to exceed 154 feet in summer and 155 feet in winter. It is currently 158 feet.

In early October the sluices at Portora were lowered to maintain water levels on the Upper Erne as the Lower Erne was drained to what a local observer described as "very low" levels in anticipation of winter storms but a month later the deluge had taken the lake to "very high" levels.

A spokesman for the Department of Agriculture and Rural Development said: " Rivers Agency can confirm that they have been working with the Electricity Supply Board to ensure that levels in the Lough Erne system were drawn down to the lowest permissible level in October 2009 to provide maximum storage capacity for winter months. In spite of this, the sheer unprecedented amount of rainfall in the Fermanagh area has resulted in the highest lough level on record."

He said the Upper Lough was approximately six feet above its "normal" height and the Lower Lough was about two feet above its "normal" level.

"However, it should be noted that it is a natural river system and as a result water levels will naturally fluctuate," he stated.

The levels are measured electronically at Belle Isle on Upper Lough Erne, Portora and Cliff but as is evident from recent events the sluices don't always achieve their main aims of preventing flooding and facilitating safe boating.

The sluices at Cliff and Kathleen's Falls have been opened to "spill" as much water as possible out of the Erne into the sea but that has not prevented the present flooding.

It could be argued Lough Erne isn't flooded; it is simply claiming back lost ground.

Prior to being drained its "normal" water level would have been four feet higher. Much of what currently lies under water is not farmland but drained lake bed.

This article appeared in Impartial Reporter 26 Nov 09

Have your say. Post a comment on this article.

john conay
Unregistered User
Nov 28, 12:38
Report comment

The e.s.b. should publish the water flow figures for the dam outlets on the erne so the public can see for themselves

what is going on here.

Has the max flow rate been maintained since the floods began?

Recommend? Yes 0 No 0

Return to the main index, get more from this section or browse our News archives.