Baltimore County, MD Tetra Tech for Lockheed Martin

Cow Pen Creek Wetland Forensic Investigation

Straughan was retained by Tetra Tech on behalf of Lockheed Martin to help resolve wetland mitigation compliance issues for the project and resolve permit closure with the Maryland Department of the Environment; with our work successfully achieving that result.


Our Approach

The overall project involved large-scale sediment remediation of a tidal tributary to Middle River in Baltimore County, MD and the Chesapeake Bay. The comprehensive project of the multi-disciplinary team involved contaminant remediation, site restoration, tidal and nontidal wetland, and submerged aquatic vegetation restoration plantings. As the project was constructed and mitigated, questions evolved regarding the total amount of mitigation needed based on impacts and the amount of wetlands constructed and achieved. Straughan was retained to forensically look at pre-existing conditions information to help determine, with professional judgement and expertise, the pre-existing wetland conditions, namely the amount of forested wetlands present prior to construction.  The investigation involved reviewing base mapping/topography, aerial photos, National Wetland Inventory wetland maps, County soil survey, monitoring report data, and LiDar mapping.  This information, along with field data collection of GPS dat, determined at what elevations mitigated wetlands and remnant unimpacted pre-existing wetlands were occurring and thriving at as well as likely pre-construction wetland conditions. The results were analyzed for wetland habitat elevation ranges, digital mapping and GIS overlay analysis for forested wetland probability.  The results were conveyed in the Forensic Wetland Investigation Report with mapping and a memorandum.  Straughan also facilitated a discussion the Maryland Aviation Administration to gain their approval of two new native wetland species for planting, since MAA regulates plantings within a flight zone bird hazard strike zone radius of Martin State Airport. The last key component of our work was presenting the Forensic Wetland Investigation Report to the Maryland Department of the Environment Water and Science Administration’s Wetlands and Waterways Protection Program to secure final approval of the achieved mitigation and close-out the wetland permitting responsibilities for the client.