Out of print publication, available as a photocopy only

Britain’s wetlands provide habitats for many species of plant and animal life, some of them rare or endangered. Public interest in conservation gives rise to pressures to retain or improve existing wetlands, or to create new ones. This may engender conflict with requirements for land drainage or river control, although in some cases, as in flood storage lagoons, interests may combine rather than conflict.

Technical Note 123 is the outcome of a CIRIA study of the problems that may arise and the possible solutions. It provides information and guidance on engineering aspects of accommodating the conservation or creation of wetlands within or adjacent to areas subject to river or land drainage improvements.

Six particular wetland areas, typifying the range of conditions and requirements likely to be encountered,were chosen from a much larger number considered in the study. These are described in detail together with the solutions that were adopted. Each area is considered under the headings of ecology, engineering, assessment of results, and costs.

The review section of the Note gives background information and enunciates general principles and lessons to be drawn from the individual studies. This contains subsections on political, economic and legal aspects, ecology, engineering methods, hydrology, soils, costs and benefits, and evaluation and monitoring.