An evaluation of ecological impact assessment procedural effectiveness over time

Environmental Impact Assessment (EIA) is an important tool to help decision-makers balance the environmental impacts of a proposed built development with its potential economic benefits. Used in most countries across the globe, EIA commonly includes an ecological component (Ecological Impact Assessment, or EcIA). However, despite considerable changes in relevant legislation, policy and guidance, there has been no recent review of UK EcIA chapter content, with the latest review having been published in 2000.This study attempts to determine the procedural effectiveness of EcIA chapters over time by comparing a new review of 112 English EcIA chapters from 2000 onwards with earlier reviews. This was achieved through the novel use of inferential statistics, an approach previously lacking in the EIA and EcIA review literature.The limitations and advantages of the use of quantitative methods are discussed. In general, there has been an improvement in the information content of EcIA chapters over time, for example in the percentage of EcIA chapters stating the size of the development and estimating the likely effectiveness of proposed mitigation measures. However, the earlier reviews highlighted such severe information deficiencies that the progress seen in the post-2000 EcIA chapter review still leaves considerable scope for improvement.Changes in the EU’s EIA Directive in force since May 2014 (and to be transposed into Member State legislation by May 2017) have the potential to encourage the use of inferential statistics in EIA and EcIA review: the requirement for Member States to provide central access to EIA information should enable representative samples to be analysed.