Welsh poets may still sense a bardic responsibility to speak for their communities. The relatively new post of national poet, currently held by Gillian Clarke, arises naturally from that tradition. Happily for the incumbent, it brings none of the royalist freight attached to the English "laureate" brand, but there are other pressing expectations. Academi, which sponsors the post, lists on its website the required skills, including "an ability to communicate, to write well and often, and to have a regular route into the magic that makes verse work". This is an un-nerving job description - not least, that surely mischievous oxymoron, "regular route into the magic ... "

Clarke's new collection, A Recipe for Water, is surprisingly upbeat and relaxed in tone. An array of sequences testifies to her creative energy, and, notwithstanding concerns over climate change, there is plenty of celebration. At the same time, some over familiar recipes are revisited. The "myth kitty" (or is it a nature reserve?) of contemporary poetry yields various recycled ingredients: a fox cub brought home in a jacket, the shipping forecast and, not least, the collection's dominant theme, water.

Dedicated to the Indian poet Sujata Bhatt, the title sequence registers ecological urgency through the experience of a drought closer to home: "You imagine me writing in the falling rain /... But day after day / no huff of rain / on the roof ... " The use of "huff", with its alliterative echo, "roof", is beautifully exact; Welsh rain inevitably announces itself in gusts of angry wind. Clarke returns to a favourite analogy, water as vocalisation, but broadens the linguistic dimension with "wysg, uisc, dwr, hudra, aqua, agua, eau, wasser". Listing seems a rather over-used device, though led by a good ear for euphony. Later in the collection, there's more notably spectacular poetic weather, vivid with "bucking calves", squally winds that "shove and shoulder", and the strange yellow glow of a landscape bathed in ominous "storm-light" ("Cattle, Hayfield, Storm").

Immediacy is Clarke's forte, but what is effective aurally, and allows audiences to appreciate hearing a poem without suspecting most of it has been left stranded on the page, may seem low-pressure in print. Sometimes, the language is plain to the point of the unabashed commonplace ("brand new", "who dares / wins", "house of dreams"). On the positive side, the poetic structures have a natural rhythm and flow, and the alliterative effects add interest to the texture.

The urban poems reflecting Clarke's earlier stint as Cardiff's laureate add zest to the collection, capturing big-city flux and buzz with plenty of sonic colour: "Buildings you knew / fall to rubble and ash / under the crush of machines, // and rising out of dust / this brash new place, / reinventing itself // in pavement cafés, / in glittering glass and steel, / in shopping, shopping, shopping // to the beat of the rapper, / to the cry of street traders, / to the Big Issue seller, / to the sweet voice of the violin" ("Sleepless").

The little scolding sigh in the repeated "sh" sounds ("shopping, shopping, shopping") is a nicely ironical touch, and cleverly picks up an echo of the Welsh "ll-ll-ll" sounds attributed to the sea in two other poems, "First Words" and "Not".

This linguistic territory is entered via tender memories and wounds - old racial hurts that left the speaker's mother reluctant even to say the word "Welsh". Clarke addresses her characteristic theme of language loss, but affirms the rising tide of linguistic self-confidence in a poem simply called "Welsh": "And here is the square, the word's on the street. / Children chatter past my pavement table / as if they own the city, as if it's ordinary / to shake the dust off a rumour, / to shimmy and shout in Welsh in a Cardiff Square."

Foreign travel suits Clarke's painterly eye. Her sequence "Mumbai" picks up the water theme, and heightens it by contrasting it with dust, heat and grime. The refreshment is palpable. A woman pouring water over herself from a jug in "At the Banganga Tank" is "moulded // in water and light"; a man "accepts / the gift of a running tap on the highway embankment / letting its bright rope run through his hands" ("Man in a Shower").

Sonnets are dotted about the collection like neat islands, composed with an easy skill and a musicality that reminds us of the melodic origins of the form: "In spring, fifteen centuries ago, / the age of saints, and stones, and holy wells, / a blackbird sang its oratorio / in the fan-vaulted canopy of the trees, / Before Bach, before walls, before bells, / cantatas, choirs, cloisters, clerestories" ("Bach at St Davids"). Diction and metaphor may be unambitious, but perhaps in a nationally responsible, accountable-to-the-people kind of poetry, private intensities and self-validating technical bravura matter less than saying tunefully what your audience is happy to hear.

 Carol Rumens's Blind Spots is published by Seren.