A quantitative assessment of stream restoration success

Reach-scale stream restoration is a common method for ameliorating stream damage, but its success is unclear as follow-up monitoring is rarely done or disclosed.  To address this we assessed the extent of macroinvertebrate community recovery in stream restoration projects throughout North Carolina for which long-term macroinvertebrate monitoring was conducted.  Assessment was performed by 1) correlating community recovery with reach-scale and watershed-scale variables extracted from reach-scale habitat maps and watershed land use patterns; 2) evaluating faunal recovery in comparison to pre-construction conditions and reference sites; 3) investigating similarities in species composition between reference and restored sites.  Projects were sampled pre-construction, and for at least three years post-construction.  Preliminary results indicate that many of the assessed projects are not meeting proposed macroinvertebrate community success criteria.  However, there does appear to be improvement in some projects where monitoring continued after five years.  The characteristics that discriminate successful from unsuccessful stream restorations may help improve and prioritize further restoration plans.