The launch of the book was memorable. Invitations to the party suggested that guests bring swimming costumes. The event was held at the Oasis open-air swimming pool in central London, where a poolside band fronted by Jacqui Dankworth played Loudon Wainwright III's wonderful Swimming Song, amongst other joyful and upbeat music.

Roger was also a filmmaker and broadcaster, following a period as an advertising copywriter and English teacher. He settled in Suffolk where he purchased a rambling farmhouse which included an ancient moat in which he swam almost every day when possible. Life there became the subject of a beautiful Radio 4 programme, "The House", which simply recorded the noises of the ancient house creaking at night, with mice scurrying behind the wainscots, owls hooting in the dark beyond, and the wind rattling the out-houses. He had a particular interest in the Southend rock-music scene, and had a penchant for the lowlife places and musicians found along the lower Thames delta (Canvey Island, Leigh-on-Sea, Southend). These enthusiasms produced several documentary films of enormous exuberance and anarchic life.

Yet he was always a committed environmentalist and one of the principal movers behind the pioneering environmental group, Common Ground. The publication of Waterlog moved Roger into a much more prominent position as a fine and passionate writer about the degradation of the world's rivers and water systems. In Britain this book created a significant change in the mood of public opinion, back towards open-air swimming (the revival of lidos is indebted to Waterlog), to greater access to the tarns, ponds and rivers in Britain, as well as the fields and landscapes in which they were set, and a rejection of the over-chlorinated, chemically enhanced, fitness culture of the gym and indoor leisure centre.

At the time of his death he had just managed to complete a second major work, Wildwood: A Journey through Trees, which will be published by Hamish Hamilton in 2007. For this book he travelled in many countries across the world (though particularly in the former Soviet bloc countries, including Belarus and Kyrgyzstan), investigating the plight of ancient woodlands and forests. It is a tragedy that he will not be here to celebrate its publication, and to promote the cause of ecological conservation he so assiduously espoused.

Roger Deakin belonged to that tradition of English topographical and literary writers – among them Ronald Blythe, Mark Cocker, and Richard Mabey – who have one foot in the library and the other foot in the distant fields. The poems of Keats, Shelley, Wordsworth and Coleridge were as immediate to him as today's newspapers. It is both a rich pleasure and a poignant moment to read again the piece he wrote for openDemocracy, "Towards Ennistone – a swimmer's journey", to commemorate the passing of a thoroughly generous and delightful man.

To read Roger Deakin's article "Towards Ennistone – a swimmer's journey", published on 4 July 2001, click here.