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MU-3 Stream Surveys - Mussels

Purpose:  To conduct comprehensive surveys on MU-3 stream reaches over the course of up to three (3) field seasons beginning with the 2018 season.

Construction - Project No:  E04152 WO #004


Reconnaissance, Phase I and Phase II survey protocols will be completed in combination to achieve the desired outcome of being able to re-classify the MU-3 stream reaches as either MU-1, having the greatest densities of T&E mussels, MU-2, having lesser densities but confirmed presence of T&E mussels or MU-5, having confirmed absence of T&E mussels as further defined in the programmatic consultation.  This research will allow PennDOT and the US Fish and Wildlife Service better plan, direct resources and design projects with construction measures that minimize effects on endangered mussels where needed.  Locations where T&E mussels are not found, or found in low densities will be deemphasized and project specific surveys will not be required.  Typical bridge replacement designs will be able to be pursued at locations where T&E are not found.  A streamlined, expedited project review process and standardized in-lieu fee mitigation will be implemented for bridge replacements crossing MU-2 streams.

Anticipated Outcomes

​Many of the MU-3 streams will be reclassified as MU-5 and will no longer require surveys on a project specific basis.  It is also anticipated that the remaining MU-3 streams will be found to be appropriate for re-classification to MU-2. Future projects in the MU-2 streams will not require additional surveying.  These will be assumed as low density and a set in-lieu fee mitigation assessed.

​PennDOT Technical Advisor:
​Antonia Zawisa
Project Duration:
​July 2018 - July 2021
Research Contractor:
​​Michael Baker, Jr., Inc.
Principal Investigator:
Robert Bondi, P.E.​
Project Cost:
$591,052.88