0:13:21 > 0:13:25# Wind blows down from the northern sky
0:13:25 > 0:13:28# Waves rise up to meet the eye
0:13:28 > 0:13:33# Fisherman bring in your line this time... #
0:18:36 > 0:18:42The sand is being pumped into the tank in a slurry -
0:18:42 > 0:18:45water and sand mixed.
0:18:45 > 0:18:49The sand is settling in the tank and the water goes overboard.
0:18:49 > 0:18:53It's virtually impossible to sink these boats.
0:18:53 > 0:18:58They were purpose-built for the job,
0:18:58 > 0:18:59they're all buoyancy tanks
0:18:59 > 0:19:03and it's practically physically impossible on a flat, calm day
0:19:03 > 0:19:06to fill that tank with the boat down.
0:19:06 > 0:19:10How much would you lift in one session like this in one load?
0:19:10 > 0:19:14Erm, about 200 tonnes would be a good load.
0:19:14 > 0:19:20At the moment, there's 17 boats working on the lough
0:19:20 > 0:19:24and at one time, these were the biggest boats in the lough.
0:19:24 > 0:19:28They're now amongst the smaller ones.
0:19:28 > 0:19:31There are boats on the lough that are carrying 300-350 tonnes
0:19:31 > 0:19:34that have been brought in by row.
0:19:34 > 0:19:37These boats come in via the lower Bann.
0:19:37 > 0:19:41These were the maximum size that the loughs on the lower Bann can take,
0:19:41 > 0:19:43120 foot by 20.
0:19:43 > 0:19:46The sand that's on the bottom of Lough Neagh,
0:19:46 > 0:19:48how did it get there? Is it glacial?
0:19:48 > 0:19:54Yeah, it was about 15,000, 12,000 years ago,
0:19:54 > 0:19:58at the end of the last ice age, as the glaciers were melting.
0:19:58 > 0:20:02I read recently that there's over a million tonnes of sand
0:20:02 > 0:20:05extracted from Lough Neagh every year.
0:20:05 > 0:20:08It's clearly a finite resource. How long will it last for?
0:20:08 > 0:20:11A million and half tonnes a year sounds a lot,
0:20:11 > 0:20:14but in comparison to the area of sand that's here,
0:20:14 > 0:20:19it's going to last a long time.
0:20:19 > 0:20:24It's been in full production since the end of World War II,
0:20:24 > 0:20:26things really started getting revved up.
0:20:26 > 0:20:29There's a lot of industries that have sprang up round
0:20:29 > 0:20:31the shores of the lough,
0:20:31 > 0:20:34you know, concrete and one thing and another,
0:20:34 > 0:20:39and all those brought jobs to the area from the sand.
0:20:39 > 0:20:43It'll not last for ever, but it's got a long, long way to go.
0:20:43 > 0:20:46I hear that most of the sand that was used to build
0:20:46 > 0:20:49Croke Park Stadium in Dublin, and also for the pitch there,
0:20:49 > 0:20:51actually came from Lough Neagh here.
0:20:51 > 0:20:54The last time the pitch was refurbished,
0:20:54 > 0:20:57I think it was about 6,000 or 7,000 tonnes
0:20:57 > 0:21:01of Lough Neagh sand went to Croke Park
0:21:01 > 0:21:04and that's the reason why Sam Maguire has come to
0:21:04 > 0:21:07the shores of Lough Neagh so often in the last few years.
0:21:07 > 0:21:09They're playing on their home ground.
0:28:32 > 0:28:35Subtitles by Red Bee Media Ltd