
Modified Charleston Method(MCM) Brenda A. Archer, Regulatory Program U.S. Army Corps of Engineers, New Orleans District (CEMVN)
Modified Charleston Method (MCM) An Assessment Methodology for evaluating • unavoidable wetland impacts associated with Section 404 Clean Water Act permits and • projects that are proposed as mitigation for those unavoidable impacts
MCM – Conditional Assessment Model • Measures wetland functional loss indirectly by • considering the quality of wetland functions of the impacted site weighed against • the perceived increases of wetland functions of the mitigation project. • Evaluates only the site as it exists at the time of evaluation.
Regulatory was tasked with developing an assessment model that: • Produced comparable mitigation requirements as other Corps Districts in Louisiana and • Promoted consistency among New Orleans District regulatory project managers with diverse backgrounds
Interagency Review Team • Federal and state resource/regulatory agencies involved in the decisions for the assessment model included: • US Environmental Protection Agency • US Fish and Wildlife Service • National Marine Fisheries Service • Louisiana Department of Wildlife and Fisheries • Louisiana Department of Natural Resources, Office of Coastal Management
Modified Charleston Method • The Charleston Method was developed by the Charleston District in collaboration with an Interagency Review Team in that District; Used by Vicksburg District • Provides comparable mitigation requirements from the other Districts adjacent to the New Orleans District. • After minimal training and practice, project managers are able to easily apply the method with a minimal about of field data collection and a high degree of consistency. • Allows unlimited mixing of mitigation locations, and types (e.g. restoration, preservation, enhancement). • Allows mixing of mitigation banks and permittee-responsible mitigation projects.
Modified Charleston Method (conti-) • Only required slight modifications for it to be used in the New Orleans District. These modifications were to account for • Regional wetland differences • CEMVN Mitigation Standard Operating Procedures • 33 CFR 332: New Mitigation Rule
MCM Operators • CEMVN permit and mitigation bank project managers for Section 404 CWA permits including restoration and/or enhancement projects • Applicants/agents • to estimate the amount of mitigation that will be required to compensate for various project scenarios (avoidance and minimization), and • to compare mitigation options
MCM Factors • MCM evaluates a suite of factors that are used to assess the potential of the site to perform wetland functions. • A factor is an element, circumstance, or influence which contributes to the overall quality of the site. • Each factor is defined by a list of options that qualify the factor based on conditions at the evaluated site. • The functional value of the site is determined by selecting the options that best fit the site conditions for each factor and then summing all the factor values.
MCM Workbook • MCM workbook is an excel spreadsheet consisting of four worksheets: • “Summary Worksheet”, • “Adverse Impact Worksheet”, • “Mitigation from Bank Worksheet”, and • “Proposed Restoration/Enhancement Mitigation Worksheet”.
MCM Guidebook • Definitions of terms used in the model • Discussions of the use of each worksheet • Definitions for each factor and option associated with that worksheet, and • Examples using each worksheet.
1. Assessment of Adverse Impacts • The model considers; • The habitat rarity or difficulty to replace, • Site wetland quality, • Work involved and the extent to which that work will impact wetland functions, • Duration of the impact • Potential for project to result in cumulative impacts.
2. Assessment of Mitigation Project The model considers: • Net improvement • Negative impacts on the site that can not be remediated, • Protection type, • Temporal loss, • Credit availability versus Credit use. • Replacement with in-kind/out-of-kind • Location of impact versus mitigation.
3. Kind and Location Factors • These factors are included when evaluating an permit project with a particular mitigation bank and/or permittee responsible mitigation project • The value for these Factors adjust the required mitigation amount depending upon the degree of variance from the most to least preferred option of in-kind/on-site to out-of-kind/out-of-watershed.
Resource for MCM Guidebook and Workbook • Located in the Regulatory In-Lieu Fee and Bank Information Tracking System (RIBITS) • Go to RIBITS from the following website: https://ribits.usace.army.mil • Once in RIBITS, Choose “New Orleans District” in the lower, left-hand side of the screen and then the “Assessment Tools” tab in the upper, left-hand side of the screen.
Contact Information Dr. James A. Barlow, Section Chief Special Projects and Policy Team (504) 862-2250 or james.a.barlow@usace.army.mil