Perspectives on Assessing Stream Restoration Projects in Maryland

As a significant component of mitigation activities, the State Highway Administration (MD-DOT) conducted numerous stream restoration activities throughout Maryland.  Since 1988, the Appalachian Laboratory (University of Maryland Center for Environmental Science) completed both pre- and post-construction biological and physical assessment studies for over 30 SHA stream restoration projects (primarily Piedmont and western Coastal Plain).  The initial long-term study design and results of this stream biological assessment work (1998-2010) are described, with emphasis on sampling modifications for more recent restoration projects since 2012.  Fish, benthic macroinvertebrates, and physical habitat parameters were determined for each restoration site (middle and lower segments) as well as both upstream (control) and downstream sites when feasible. Generally, each stream restoration site strongly responded to upstream watershed characteristics.  Site-specific statistical analyses are presented for 12 noteworthy SHA restoration projects, with an emphasis on extrinsic and intrinsic factors that may potentially affect stream restoration success.  Critical to the assessment of all stream restoration projects is the ability to establish a pre-construction baseline (1-2 years), followed by a post-construction period (2-4 years) after stream restoration activities are completed and stabilized. Three “gold standard” SHA projects are highlighted, along with basic recommendations to advance Maryland stream restoration activities.