Since the establishment of the Toronto and Region Area of Concern in 1985 there have been marked improvements in water quality and sediments. These improvements have led to the re-designation of five beneficial use impairments as unimpaired. For the remaining six beneficial use impairments (five listed as impaired and one requiring further assessment), efforts are underway to assess their status and identify actions that could lead towards their re-designation. Here we introduce a series of nine articles that establish benchmarks of current conditions, provide critical supporting information to undertake an assessment, or directly assess (or re-confirm) the status of a beneficial use impairments.

自1985年成立多伦多和受关注地区区域以来，水质和沉积物已有了显着改善。这些改进导致将五种有益用途减损重新指定为未受损。对于其余六种有益用途减损（五种被列为减损，其中一项需要进一步评估），正在努力评估其状况并确定可能导致其重新指定的行动。在这里，我们介绍了一系列九篇文章，这些文章建立了当前状况的基准，提供了重要的支持信息以进行评估，或者直接评估（或重新确认）有益使用损害的状态。