Abstract

Wetland construction represents a vital tool to increase the number and extent of wetlands in the United States. However, there is uncertainty as to how effective constructed wetlands actually are and if they continue to function efficiently as they age. This study’s objective was to evaluate the constructed wetlands on Grand Valley State University’s Allendale campus. The wetlands studied were constructed in both 2009 (n=3) and 2011 (n=5), not specifically to mitigate for wetland loss; rather they are a proactive attempt to reduce erosion from excessive stormwater runoff in the GVSU ravines. We compared these to wetlands constructed in the mid 1980’s (n=3) located at the near-by Bass River Recreation Area. Specifically, aquatic macroinvertebrates were sampled throughout May 2012, following rapid bioassessment protocols used by the Michigan DNR, while water chemistry parameters (specific conductivity, pH, dissolved oxygen, temperature, turbidity, riparian coverage, chloride, and total dissolved solids) were measured bi-weekly throughout the summer. The macroinvertebrate Family richness and diversity were significantly different (p<0.05, ANOVA) and values for each metric ranged from 21.3, 20.67, and 6.6 and 2.31, 2.13, and 1.01 between 1980’s, 2009, and 2011 sites, respectively. These differences in the insect community assemblages were evident in a multivariate test as well (NMDS). Thus, at a community level there was a rapid improvement in the aquatic insects in just three years suggesting these constructed wetlands will rapidly develop into healthier communities.