The Atlas includes distribution maps of 174 species of water beetle and 47 species of water bugs, representing approx. 65% and 72% of the British species, respectively. Each distribution map, which is based on 1 kilometre squares of the national grid, is accompanied by an account of the habitat in which the species is found, along with information about its local status and the localities where it occurs. Included in the book are 27 photographs of wetland sites, encompassing habitats such as bog pools, canals, dykes, gravel pits, woodland ponds, springs and rivers, each with details of the beetle and bug communities which they support.
The book also includes a chapter introducing the reader to water beetles and water bugs and other chapters describing the background to the survey, the study area, sampling techniques and the dataset upon which the maps are based. This dataset comprises 37,000 records gathered during 1993-2005, mostly from the author's own fieldwork. A number of appendices give additional information such as maps showing biodiversity hotspots for water beetles and water bugs, checklists of species together with their national statuses and tables listing the many noteworthy sites within the study area.