Ken Grant's dense, intimate photographs of his native Wirral are arecord of a hidden world undergoing a process of rapid change, he tellsKevin Barry

The Wirral Peninsula, a little cow-horn of land jutting out from Merseyside into the Irish Sea, is 18 miles long by seven wide and contains all human life.

Or so it can seem when you look at Ken Grant's photographs of the place, showing in Dublin now and depicting a world that was once bucolic, and then derelict, and which has lately been host to a tentative prosperity.

These are pictures of drinkers and smokers, of moon-faced men idling by the water, of cots and TVs, with lots of white vans and sooty buses, with dogs always prowling and kids underfoot.

The work is intimate and dense; it has a sweaty familiarity. If all our suburbs have lately become the same suburb - with the discount supermarkets, the DIY cathedrals and garden care emporia, the call centres for the shopping channels - then maybe you can be homesick for a place like the Wirral without ever having been there.

Grant is a Wirral native and he's been photographing his home ground for the best part of 20 years, with occasional forays across the Mersey to Liverpool. His exhibition at the Gallery of Photography in Temple Bar is called The Close Season and is culled from a book of the same name. The title suggests a certain humidity, which would be apt. To lapse into cliché, this is work that's up close and personal.

"What happened in the first place," Grant says, "is I was working with my father, I was a kind of labourer and every day I was going into these places, these workshops, and they were places that people just didn't see usually. It seemed like a hidden world, a completely different social space. So I started taking a camera along."

This was the mid-1980s, along the shores of the Mersey, when it was all oily bustle and clank there, and these workplaces were carved from the junkyard chaos. They made up a parallel universe, with their own strange rituals and tropes. The undercurrents were occasionally dark; Grant says you could sniff the racism sometimes. It was a place where change was about to come.

"People would move on very quickly, that was the nature of it anyway," he says. "My ever-changing colleagues, I called them. But there were things happening politically at this time. There was the feeling that things weren't forever any more."

The bustle has long since stilled and the river life around the Wirral has lost much of its vivacity. When the work changes, the feel of a place changes.

"This is one of the things you notice, how all the old routines have changed or are just gone," he says. "A lot of it has got to do with the fact people aren't working nine-to-five any more."

Now, it's the era of flexitime and contracting. Look out the window and it's like somebody has been messing with the clocks. There used to be a tight schedule out there, with milkmen in the mornings, and dads slouching home in the evenings, and shaky pensioners on strolls you'd set your watch by. Now it can seem as if everybody is out and about all the time, or some days as if nobody is.

"I've been photographing people out drinking and out in parks, and you notice the way everyone is off at different times now. Everybody has a different weekend," Grant observes.

His work is sometimes densely populous, as in the drinking scenes, with a sense of people thrown in on each other, and sometimes it's lonesome as the moon. It can seem haunted, with an ache to it, memorial to an era that's rapidly receding. He has an old- fashioned commitment and a natural loyalty to his subject.

"When you know the particular idiosyncrasies of a place, there's a responsibility to find the right way to picture that and what it takes is time," he says. "Any photographer will tell you the same. You can be out there five, six, seven days trying to get something and it'll come on the eighth day. Just being there is the work really."

It's not so much that he colludes with the subject-matter, it's more that he's part of it himself. The Close Season reads like memoir.

"I work very slowly. If I'm taking photos somewhere, I'll have been invited," he says. "I might be out with people through the football, say. People know what I'm doing and they know who I am."

He is sometimes placed in a tradition that dates back to photographers like Humphrey Spender in the 1930s - think glum faces under flat caps in Depression-era Bolton. He isn't comfortable with this.

"I was always aware of that work, that whole genre, but somehow I was nearly always disappointed with what came out of it," he says.

"Their process was a kind of dipping in and dipping out, and if things happened for them it was an accident. The subject-matter is similar, but the work that comes out of it, well, you have to ask what kind of narratives are being made. I never liked when you were given a tidy beginning, middle and end, because life never seemed like that to me."

Grant talks about narrative a lot. His work might share a sensibility with other photographers - Martin Parr, say, with his burnt Brits on the heaving costas, or Richard Billingham, with his Ray's A Laugh family album - but it's as easy to place him in terms of contemporary writing. It's no accident that a short story by James Kelman is included in the Close Season book. He'll nod an affinity also to Iain Sinclair, purveyor of blackly comic "psycho-geographies" from London and its environs.

He feels documentary work of the type he specialises in is viewed as peripheral now, though this hasn't stopped his photos being acquired by the Victoria and Albert Museum in London and the Museum of Modern Art in New York.

"I think a lot of people are using the form, they're using the documentary techniques, but it's for their own ends. It's like they feel no obligation to the subject-matter," he says.

He remains firmly obligated. He had the camera out last weekend, out in the small world of the Wirral, a world that's slipped on to a new set of cogs.

"It is different on the river. The work is still there in terms of sheer tonnage, in terms of what's going through the port, but the people are gone and lots of the trades have disappeared," he says. "This has implications for all of the places just beyond the river. Pubs down there where I used to hang around, playing pool, they're either completely empty or they're being rendered for office space."

He got his first camera when he was 11 years old. "We'd go on holidays to places in north Wales, caravan parks, and that was the start of it," he says. "You only had eight frames to play with on the Polaroid, so you didn't have anything to spare."

It shows in his photographs, each one a short story.

There's a bride and groom in a function room. She's got fresh highlights and a flower in her hair. He smokes a ritual cigarillo. They look both hopeful and scared, as if things could go either way.

There's a couple down the boozer, with a table full of drinks in front of them, stout and bitter, Bacardi and Coke. He has his arm around her and he's filling her head with talk. She looks as if she half believes it.

There are kids on the beach, their bikes thrown about, with the city brooding across the water, and the rooftops in shadow. The summer sky is light and immense.

The Close Season, photographs by Ken Grant, shows at the Gallery Of Photography, Meeting House Square, Dublin until April 20th