Open sea races offer an opportunity for convivial, friendly competition for swimmers of all ages. All you need is a hardy disregard for the cold. Sara Keatingtakes the plunge

The water is so cold, I think my heart has stopped, but adrenalin quickly jolts it back to life. The salt tastes bitter in my mouth, and I am gagging as I gasp for air. The underwater world is green and murky, and I cannot see anything except the movement of the bodies close beside me, and the graceful reach of Catherine Egan, my "go lady", swimming just ahead. I am a trained pool swimmer, can swim 1800m easily in a session, and swim, on average, 5000m a week. But in the wash of ocean in Dublin Bay, I am literally out of my depth.

It is one of the finest days of the summer, and there are approximately 200 swimmers gathered together to participate in the Cyril Duff Memorial Race at Seapoint.

The annual Open Sea swim season is in full swing in a busy calendar, which kicks off in June and runs straight through to September.

Three consecutive races occurred over the August bank holiday weekend: this first one at Seapoint on Saturday afternoon; a second in Wicklow Harbour on Sunday; and a third on Monday, beginning on Greystones beach. Most of the swimmers took part in all three, and by the end of the summer some will have swum in all 30 of the races organised by the Leinster Swimming organisation. The volume of activity, the dedication of participants, makes it sound almost like a professional competitive sporting meet.

However, Brian Mongey, who sits on the board of the organising committee explains that the annual Open Sea Races "provide a very open, friendly, convivial type of racing, and they attract all sorts of people from all different backgrounds. In the men's group, the ages range from 13 up to 84; with women, there are swimmers who are 14 years of age and some in their 60s. And the ability ranges too, from swimmers in post- or pre-Olympic training, to people who just get in and do it."

Jane Reid, chairman of the Open Sea Committee, explains: "The tradition of open-sea racing stretches back to the heydays of the DúLaoghaire baths, the baths in Sandymount, the baths in Howth. Originally, in our generation [ the more modern era of open-swim racing] most of the swimmers would have played [ water] polo as kids. They would have played in Blackrock baths, and they had to train in the sea, because you needed to be able to swim in cold water.

"Polo coaches used to say to them 'get in there, and swim over there', and that became their training, so many of our races grew from that." However, as Mongey elaborates, since the closure of many of Dublin harbour's baths, "the family of swimmers, the fraternity, has broadened out. It used to be predominantly polo players, but now they would be in a minority. There are more people who just swim".

"It's amazing the amount of people who see what we're doing every summer and think it's great and just approach us," says Reid. "We get many members coming to join our club in the summer. We train primarily indoors in the winter - you would want to be fairly hardy to swim a mile in the sea in November - but people want to join in the summer because they like to swim outdoors."

The organisation's affiliation with Dublin City Council and DúLaoghaire Harbour Board means that the open swim races are governed by the highest safety standards. Mongey explains: "We go to the nth degree with our planning of the event; our game has to be up there. We have the Civil Defence and trained personnel to look after races. We run safety courses for the clubs, and operate a safety template that all the clubs use. Also, 99.9 per cent of the swimmers are known to us before they swim. It is an absolute exception for us not to know whether someone can manage."

At the moment, open-swim races are largely confined to the Dublin region. "Around the rest of the country, unfortunately, there are no organisations [ for open-sea swimming], so people tend to swim on their own," says Reid. "There wouldn't be a big gathering like this. We're trying to encourage and support them - because we have the support here, we're trying to say if you want a bit of help in organising, come and ask."

Sitting on the sea-front only 10 minutes before he is due to start in the men's race, Mongey explains that most of the open-sea races are not competitive: "The way the races actually work is that the slowest of the swimmers will go first, they actually go before the official 'go' and the fastest swimmer goes last. It's Joe's job to decide what time each swimmer sets off at."

Joe Browne has been setting the handicaps for the races for the last 22 years, and says, "It's like an upside-down handicap. We try to spread the prizes. We try to be fair and try to mix it around. It's not a championship race."

Mongey explains: "The handicap runs over seven minutes, with swimmers beginning at different times, and this allows the bulk of the swimmers to come in to the finish together over the space of a minute. Joe will nearly know everybody by name, by face, and he'll record it on a tape recorder as they come in."

It's frantic, Mongey says, but it certainly makes for a dramatic finish. At the half-way point, the men in the distance look like seagulls, the span of their arms as they reach and pull like birds' wings beating against the water. As the men near the finish, the bright colours of their swimming caps bob up and then down again as their heads spin to either side to breathe. As the swimmers begin to finish, one soon after another, they clamber up the steps at Seapoint harbour calling out their names in a clamour to have their times recorded - although there is one clear winner, Pat Chambers, who came in at an impressive time of 18 minutes, 32 seconds, a full minute before his nearest rival.

As for the women's race, Clodagh Nolan was a clear winner too, but, flailing along at the tail end of the group, I missed her dramatic 19-minute finish.

I finished 85th out of 89 swimmers, while my patient swimming partner, Catherine Egan, came in at 83rd, having hung around the back with me as I swallowed and spat water, lost my swimming cap, and my nerve, and considered calling over the Civil Defence Team in their dinghies to haul me out of the water.

"You'll get used to the cold," she had told me, as we waited to start, "but there's nothing worse than being pulled out of the water by the lifeguards.

"And you know," she said reassuringly as we neared 400m from the finishing banner, "if you swim just a little bit faster, you won't come last."

As I paddle in to the finish, exhausted, the exhilaration sets in. The sense of achievement grows on me as I climb out of the water and my limbs begin to live again and I can feel my fingers and toes. I am disappointed for Catherine, who surely lost her place in the race as my partner. But who knows, maybe next year, with a bit of proper training, I may be able to do it on my own.

Open season

The Open Sea Race calendar begins in June, but events continue until the close of the season, including the two championship races, the Dún Laoghaire Harbour Race on Sept 2 and the Liffey Swim on Sept 15. Meantime, the Dr Winckworth races take place in Lough Owel, Mullingar, on Aug 26.

The Irish Long Distance Swimming Association, which operates out of the North and northeast of the country, has two further events in its summer season, a 2km swim at West Bay, Portrush, Co Antrim, on Aug 25, and a 5km swim from Rathmullan to Buncrana in Lough Swilly, Co Donegal. The final Open Sea meet, the Cork Masters' race to Sandycove Island, will take place in Kinsale on Sept 22.

For details see: www.swimleinster.com, www.swimireland.ie and www.ildsa.info.